Albatros D.II(Oef) Series 53

  Impressed by the successful debut of the Albatros fighters on the Western Front in August 1916 and their fine handling characteristics, the LFT and industry moved with uncommon alacrity to put the Albatros D.II and D.III fighters into production in order to meet the increasing strength of the Italians and to replace the dangerous Brandenburg D.I fighter. Oeffag, having secured license rights from the German Albatros company, had production well under way when the contract was signed on 4 December 1916, calling for 50 aircraft, originally composed of 20 D.II and 30 D.III fighters.
  The Oeffag-built D.II differed but slightly from its German counterpart. The engine, a 185 hp Daimler, was more powerful. The wing chord was increased by 10mm (0.4 in) and the fuselage was slightly altered. The D.II production prototype, 53.01, first flew in January 1917. The common D.II/D.III fuselages were completed in February, but assembly of the wing cellule for both was postponed until completion of the static load tests. Flight trials were delayed by the sub-zero weather and also had to await the development of a proper radiator and selection of a suitable propeller. Finally the D.II(Oef) was released by a Flars engineering commission on 4 May 1917, whereupon 16 machines (all that were built), numbered 53.01 to 53.16, were accepted and promptly dispatched to the Front. All but two aircraft were armed with one or two machine guns fitted with the Bernatzik synchronization mechanism.
  The majority of the Albatros D.II(Oef) fighters were sent to the less-active Russian Front to serve with Fliks 3, 5, 7, 10, 14, 20, 22, 25, 26, and 37. The D.II was also flown by Fliks 2, 19, 35, 41/J, 42/J, and 46 on the Isonzo Front and Fliks 21, 24, and 48 in the Tirol. Although a few victories were recorded, in general the D.II(Oef) fighter served to introduce two-seater pilots to the vagaries of handling a facile, high performance aircraft. Its operational function was well described in a Flik 37/D appreciation: "...too slow, its rapid climb has little effect because Russian aircraft practically never cross the lines; therefore the D.II mainly performs escort work." By the end of 1917, the D.II(Oef) was relegated to training duties, and two were offered for sale by the Austrian government in 1920.

Albatros D.II(Oef) Series 53 Specifications
Engine: 185 Daimler
Wing: Span Upper 8.50 m (27.89 ft)
Span Lower 8.00 m (26.25 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.70 m (5.58 ft)
Dihedral Upper 0 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.35 m (4 43 ft)
Stagger 0.12 m (0.39 ft)
Total Wing Area 24 sq m (258 sq ft)
General Length 7.35 m (24.12 ft)
Height 2.71 m (8.89 ft)
Track 1.80 m (5.91 ft)
Loaded Weight 898 kg (1980 lb)
Maximum Speed: 170 km/hr (106 mph)
Climb 1000m (3,281 ft) in 4 min 30 sec
2000m (6,562 ft) in 7 min
3000m (9,843 ft) in 12 min 30 sec


Albatros D.III(Oef) Series 53.2

  Production of the Albatros D.III(Oef) had kept in step with the D.II (sharing a common fuselage, undercarriage, and tail surfaces) to enable Oeffag to switch to D.III output as soon as the static load tests of the re-designed "sequiplane" wing cellule were satisfactorily completed. Not content with the original German design, Oeffag engineers developed a stronger wing and airframe - in the process creating a tough, beautifully-built aircraft that could take increasingly more powerful engines without extensive modification. The popular Oeffag-built D.III fighter remained in production until the end of the war in three different series:
Qty Series Number Engine Order Date
34 53.20-53 185 Dm 4 December 1916
11 53.54-64 185 Dm 3 February 1917
61 153.01-61 200 Dm 3 February 1917
50 153.62-111 200 Dm 18 July 1917
100 153.112-211 200 Dm 8 October 1917
70 153.212-281 200 Dm 18 May 1918
230 253.01-230 225 Dm 18 May 1918
100 253.231-330 225 Dm August 1918
  The maiden flight of the D.III(Oef) production prototype, 53.21, took place in mid-February 1917. The Flars engineering commission, after inspecting the prototype on 4 May, specified several minor modifications. Production acceptances which began on 17 May were interrupted to repeat the static load test of the wing cellule (on 26 May) as a precautionary measure triggered by reports of recurring D.III wing failures on the Western Front. The far-sighted action of Oeffag engineers was vindicated for, by refusing to copy the German wing cellule, they had made significant improvements which were outlined in an LFT report: 1) The German spars and ribs are appreciably weaker than those of the 53.2 series. 2) Ribs between the main and auxiliary spar are solid and constructed of heavier plywood. 3) Spar flange thickness is increased from 10 to 20 mm at stress points. 4) Metal reinforcing is added between the main and auxiliary spar. 5) The front auxiliary spar is prevented from twisting by a metal fixture at the fuselage juncture. The German and Oeffag-built machines were dimensionally identical, with only small variations in wingspan, gap and area. Fully loaded, the Oeffag-built D.III was heavier than the German D.III, weighing 964 kg (2126 lb) compared to the German D.Ill's weight of 912 kg (2010 lb); the difference was due to the heavier 185 hp Daimler engine. Greater power gave the D.III(Oef) series 53.2 fighter a higher rate of climb and a maximum speed of 180 km/h (112 mph), as compared with the 165 km/h of the 160 hp Mercedes-powered German fighter.
  Output grew rapidly but the shortage of synchronization mechanisms, a chronic problem, forced Oeffag to manufacture precision parts to keep production moving. An enthusiastic reception met the first D.III(Oef) fighters when they reached the Front in June 1917. Finally, squadrons possessed a fighter that an average pilot could fly with relative ease and safety. By September 1917, sufficient experience had been gathered to assess the fighter's virtues and shortcomings. Although the series 53.2 and 153 were equal in speed to the Brandenburg D.I, they had a much superior rate of climb, showed excellent maneuverability and above all, were regarded as safe aircraft. Only one Flik reported lower wing vibration. At first the fighter was not fully trusted in a steep dive (nor was this recommended), but this restriction was lifted on later models. The synchronization mechanism was often unreliable, an all too common problem, and the steel-tube machine-gun supports required strengthening. A weak tail skid structure and poor quality cowling fasteners were problems quickly corrected. The 45 Albatros D.III(Oef) series 53.2 fighters were distributed among many Fliks on the Italian Front and in smaller numbers on the Russian Front. They formed the initial complement of Flik 51/J. When production ended in July 1917, the series 53.2 was replaced by the structurally identical but more-powerful D.III(Oef) series 153. With the appearance of newer fighters, the series 53.2 was used as a fighter-trainer by frontline training units.

Albatros D.III(Oef) Series 53.2 Specifications
Engine: 185 Daimler
Wing Span Upper 9.00 m (29.53 ft)
Span Lower 8.73 m (28.64 ft)
Chord Upper 1.50 m (4.92 ft)
Chord Lower 1.10 m (3.61 ft)
Dihedral Upper 0 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.47 m (4 81 ft)
Stagger 0.22 m (0.72 ft)
Total Wing Area 20.56 sq m (221 sq ft)
General Length 7 35 m (24.12 ft)
Height 2.80 m (9.19 ft)
Track 1.80 m (5.91 ft)
Empty Weight 690 kg (1521 lb)
Loaded Weight 964 kg (1980 lb)
Maximum Speed: 180 km/hr (112 mph)
Climb: 1000m (3,281 ft) in 3 min 20 sec
3000m (9,843 ft) in 14 min 30 sec
5000m (16,405 ft) m 32 min


Albatros D.III(Oef) Series 153

  As soon as it became available, the high-compression 200 hp Daimler engine was mounted in the standard production airframe and output continued under the designation Albatros D.III(Oef) series 153. Between July 1917 and June 1918 a total of 281 fighters, numbered 153.01 to 153.281, were delivered. The second production batch, starting with airframe 153.112, was designed with a rounded nose to eliminate the spinner, which was prone to fly off and damage the airframe. In addition, German wind tunnel tests had demonstrated that replacing the spinner by a simple, rounded nose improved propeller efficiency, which in this case resulted in a speed increase of some 14 km/h (9 mph). Armament consisted of two buried Schwarzlose machine guns mounted with butts projecting into the cockpit and firing through blast tubes mounted alongside the engine. The slow-firing guns and often erratic synchronization systems were universally damned by pilots, more so because the D.III was an extremely stable gun platform. When several Fliks suggested that the guns be raised to eye level, three such fighters were built by Oeffag (153.161, 153.162, 153.181) and sent to the Front for evaluation. However, raised, cowl-mounted guns were not installed on production machines until the advent of series 253 in mid-1918.
  The introduction of the series 153 fighters coincided with the formation of specialized fighter squadrons, such as Fliks required performance and flight characteristics to engage in successful combat with enemy aircraft of similar type. It is the best-liked fighter at the Front." In the opinion of Offizierstellvertreter Friedrich Hefty, a Flik 42/J pilot credited with five victories, the "200 hp D.III was a superbly-designed aircraft, beautifully balanced and especially suited for aerobatics. Its rate of climb was equal to the Hanriot and the Camel, but slower in level flight than the SPAD." Every Flik lauded the D.III's all-round qualities. Not only was it robustly built and well finished (an Oeffag hallmark), but also its ease of maintenance endeared it to ground personnel. As usual the rocky airfields took their toll. In January 1918, seven Flik 55/J fighters were withdrawn for two weeks to repair rear airframe damage that occurred during take-off and landing. Oeffag raised the tail-skid support by 6 cm (2.4 in) to prevent the tail from bottoming out. Due to the temporary shortage of high-grade wing-bracing wire, some series 153 fighters were delivered in late 1917 with inferior stranded cable, which stretched to such a degree that lower wings began to vibrate in flight and allowed the wings to take on a pronounced V-form.
  In January 1918, Flik 42/J, a crack unit, submitted a combat summary which stated that "enemy aircraft are encountered in flights of eight or nine machines. To attack the well-coordinated enemy with inferior numbers is a hopeless task. In doing so our squadrons suffer inevitable losses without being able to control the air. The only solution is to attack the enemy in equal numbers; only then will the effectiveness of our type 153, powered by the high-compression engine (200 hp Daimler), reach its full potential. The supply of new fighters is totally inadequate." A rough indication of the combat attrition is shown by the following statistic. In August 1918, some 142 series 153 fighters were listed in the frontline inventory; three months later, the LFT's inventory was reduced to 57 machines, of which only 12 were in flyable condition. In spite of the high losses, an important fact to remember is that in terms of victories scored, the Albatros D.III(Oef) series 153 leads the list of all Austro-Hungarian fighters. This is a tribute to the aircraft and the pilots of the specialized fighter units, especially Fliks 3/J, 41 /J, 42/J, 51/J, 55/J, 56/J, 63/J, and 68/J, who fought gallantly and held their own against great numerical odds on the Italian Front.

Albatros D.III(Oef) Series 153 Specifications (With Spinner)
Engine: 200 hp Daimler
Wing: Span Upper 9.00 m (29.53 ft)
Span Lower 8.73 m (28.64 ft)
Chord Upper 1.50 tn (4.92 ft)
Chord Lower 1.10 tn (3.61 ft)
Dihedral Upper 0 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.47 m (4.81 ft)
Stagger 0.22 m (0.72 ft)
Total Wing Area 20.56 sq m (2.2.1 sq ft)
General: Length 7.35 m (24.12 ft)
Height 2.80 m (9.19 ft)
Track 1.80 m (5.91 ft)
Empty Weight 710 kg (1566 lb)
Loaded Weight 987 kg (2176 lb)
Maximum Speed: 188 km/hr (117 mph)
Climb: 1000m (3,281 ft) in 2 min 35 sec
2000m (6,562 ft) in 6 min 35 sec
3000m (9,843 ft) in 11 min 20 sec
4000m (13,124 ft) in 18 min 50 sec
5000m (16,405 ft) in 33 min


Albatros D.III(Oef) Series 253

  On 18 May 1918, Oeffag received a contract to supply 230 Albatros D.III(Oef) series 253 fighters, numbered 253.01 to 253.230, to be powered by the improved 225 hp Daimler engine that was just entering quantity production. An additional batch of 100 series 253 fighters, numbered 253.231 to 253.330, was ordered in August with delivery scheduled to end in December 1918. Requiring only minor internal modification, the series 253 began to replace the series 153 in May 1918 and continued in production until the war ended. Counting the 30-odd machines completed after the war, Oeffag built a total of 260 series 253 fighters.
  The first units to receive the new 225 hp fighter were Fliks 61/J and 63/J in mid-June 1918, whose pilots were lavish with praise. Flik 61/J labelled it as "first class and superior to any fighter." Flik 63/1 considered the new fighter as "equal to all combat requirements; it is very much liked, only the squadron does not receive sufficient numbers." By July 1918, seven fighter Fliks acclaimed the series 253 as the finest fighter they had flown. Flik 56/J reported the series 253 "meets every demand, is solid and well constructed, climbs rapidly and is preferred over the Aviatik D.I because of its peerless flight characteristics." When various LFT staff officers at the Front were asked to summarize their requirements for future planning the reply was unanimous: "Unquestionably the most maneuverable and safest fighter at the Front. It has the pilots' complete trust. Because of its excellent handling and performance, it is preferred over every other fighter. Mass production is urgent." Given full priority for materials and engines, Oeffag responded by increasing average monthly output of the series 253 by 50 percent over the series 153.
  Among the 24 participants that competed in the Fighter Evaluation at Aspern in July 1918, only three were standard production machines - the Aviatik D.I 338.03 and two Albatros D.III(Oef), 253.32 and 253.35. In spite of having the highest wing loading, the Albatros fighters achieved a faster rate of climb than all other contestants with exception of the Aviatik D.I and the WKF 80.10 (D.I) prototype. Oberleutnant Benno von Fiala recommended returning the raised machine guns to the buried position (as in the earlier series) because blowing gases and oil interfered with aiming. In this connection, Flik 61/J reported that pilots flying machines with raised guns were forced to sit on two cushions to use the sights properly. At least up to aircraft 253.116, series 253 fighters left the factory armed either with buried or raised guns, apparently at random. Whether raised armament was planned as standard equipment on later production aircraft is not known.
  As of 1 August 1918, sixty-six series 253 fighters were at the Front, serving primarily with Fliks 3/J, 41/J, 42/J, 51/J, 55/J, 56/J, 61/J, and 63/J. By October 1918, all but 29 of the initial production batch had been accepted. After the war, Poland purchased 38 series 253 fighters (253.212-230, 232, 234-239, 243-248, 252-254, 256, and 257). So impressed was the Polish air service that in August 1919 Oeffag received a letter of commendation, praising the engineers and mechanics for the "exceptional, diligent and thorough work" done on the series 253. Several series 253 fighters took part in Austrian Volkswehr skirmishes with the troops of the new Yugoslavian state in Karnten until fighting finally ceased in June 1919.

Albatros D.III(Oef) Series 253 Specifications
Engine: 225 hp Daimler
Wing: Span Upper 9.00 m (29.53 ft)
Span Lower 8.73 m (28.64 ft)
Chord Upper 1.50m (4.92 ft)
Chord Lower 1.10 m (3.61 ft)
Dihedral Upper 0 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.47 m (4.81 ft)
Stagger 0.24 m (0.77 ft)
Total Wing Area 20.56 sq m (221 sq ft)
General: Length 7.43 m (24.38 ft)
Height 2.64 m (8.67 ft)
Track 1.80 m (5.91 ft)
Empty Weight 722 kg (1592 lb)
Loaded Weight 995 kg (2194 lb)
Maximum Speed: 202 km/hr (125 mph)
Climb: 1000m (3,281 ft) in 3 min 5 sec
2000m (6,562 ft) in 7 min 10 sec
3000m (9,843 ft) in 11 min 20 sec
4000m (13,124 ft) in 17 min 15 sec
5000m (16,405 ft) in 27 min

Aviatik 30.14

  The 30.14 prototype is significant in that it was the first fighter designed and built entirely in the Dual Monarchy. On 8 June 1916, Berg proposed to the LFT a biplane fighter powered by a 160 hp Daimler engine, armed with a fixed machine gun, and having a calculated top speed of 185 km/h (115 mph). Concurrently, Berg also proposed a light reconnaissance monoplane powered by a 120 hp Daimler engine. Neither project was approved by Flars because Aviatik was barred from engaging in prototype work in order devote full effort to the Knoller program. When Uzelac got wind of the fighter project in August 1916, he fortunately intervened to support the Aviatik proposal.
  Construction of the 30.14 fighter prototype started in August. The uncovered airframe was inspected on 26 September by Flars engineers who listed various shortcomings for correction, especially strengthening the steering controls and flying surfaces. On 16 October 1916, the 30.14 stood ready for its maiden flight at Aspern. It was a clean biplane of pleasing lines, marred only by the tail assembly which appears undersized in relation to the airframe. The high center-section struts provided an unobstructed field of view. It was the first step towards the more compact D.I fighter, to which it bore an unmistakable family resemblance.
  Feldwebel Ferdinand Konschel, an experienced Flars test pilot, was carefully briefed for the maiden flight. Ingenieur Julius Kolin recalled warning Konschel to exercise caution, but his counsel was shrugged off by Berg. According to Kolin's theoretical calculations, Berg's experimental airfoil could demonstrate an extreme center of pressure shift under certain flight conditions. Berg had adopted a Knoller-type airfoil whose rib section had a pronounced reflex curvature at the very narrow trailing-edge section. Although the airfoil was judged efficient for high speeds, little was known about its low speed and stall characteristics.
  In the face of unpredictable wind gusts, Konschel had intended to perform only a few preparatory hops. Witnesses reported that after some 30 meters of low hops, Konschel unexpectedly lifted off - involuntarily according to some. With the engine at low rpm, he wove a wobbly flight path and executed a flat turn at 100 meters height. As Konschel throttled back to land, the prototype plunged straight into the ground. The crash protocol blamed Konschel's death on "a nose-heavy aircraft and inadequate control surfaces." The official inquest, however, attributed the crash to control-pulley failure. Nevertheless, Kolin remained certain that the center of pressure shift was the real culprit. With Knoller's assistance, Kolin designed a new airfoil for use on future Aviatik aircraft. Though beset by misfortune, the 30.14 prototype was the progenitor of the Aviatik D.I fighter that remained in service until the end of the war.

Aviatik 30.14 (Single-Seat Fighter) Specifications
Engine: 160 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Chord Upper 1.60 m (5.25 ft)
Chord Lower 1.50 m (4.92 ft)
General: Length 6.86 m (22.51 ft)
Loaded Weight 715 kg (1577 lb)


Aviatik 30.19, 30.20, and 30.21

  On 25 September 1916, Flars approved three fighter prototypes based on the 30.14 design and incorporating some 40 improvements specified by Flars. Three prototypes, designated Aviatik 30.19 to 30.21, were built; one for flight evaluation, one for static tests, and one as a spare. Aviatik was directed to proceed with all possible speed.
  Originally scheduled to start flight tests in November 1916, the 30.19 airframe inspection by Flars was delayed until 28 December, and the maiden flight took place on 24 January 1917. The Aviatik 30.19, prototype for the Aviatik D.I, here retro-fitted with a one-piece upper wing, during flight evaluation at Aspern.
  LFT pilots were cleared to fly the 30.19, powered by a 185 hp Daimler engine, on 13 February. Flars test pilot Oberleutnant Oskar Fekete reported on 31 March 1917 that the 30.19 had flight characteristics similar to the Aviatik C.I but was superior all around. Fie emphasized the fighter's "fabulous climb and enormous maneuverability" and felt that any competent two-seater pilot should be able to fly the type without prior schooling. On 15 May 1917, the 30.19 prototype (retro-fitted with a one-piece upper wing) and the first production Aviatik D.I, 38.01 were dispatched to Fluggeschwader I (later renamed Flik 101/GJ on the Isonzo Front for evaluation under frontline conditions. Armed with a free-firing machine gun mounted on the upper wing, the 30.19 was flown at the Front by Hauptmann Karl Sabeditch from 18 May until July 1917, when it was badly damaged and written-off. On 23 May 1917, Sabeditch downed a Caproni bomber, thereby achieving the first victory both for himself and an Aviatik fighter aircraft (30.19).
  The 30.20 prototype failed the load test on 17 March. A one-piece wing was designed to replace the two-piece upper wing and cabane center-section. As soon as the 30.20 passed the third load test on 28 April 1917, the design was released for production as the Aviatik D.I series 38 fighter. The 30.20 prototype was written-off after the load tests.
  The 30.21 was used for flight trials until February 1917, when, after a minor landing mishap, the airframe was modified by Aviatik as the prototype for the Aviatik D.II and renumbered 30.22.

Aviatik 30.19 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 7.84 m (25.72 ft)
Gap 1.35 m (4.43 ft)
General: Track 1.80 m (5.91 ft)

Aviatik 30.20 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 7.92 m (25.98 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.30 m (4.27 ft)
Dihedral Upper 0 deg
Dihedral Lower 0 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.35 m (4.43 ft)
Stagger 0.25 m (0.82 ft)
Total Wing Area 20.4 sqm ( sq ft)
General: Length 6.86 m (22.51 ft)
Height 2.50 m (8.20 ft)
Track 1.80 m (5.91 ft)
Empty Weight 734.5 kg (1620 lb)
Loaded Weight 854.5 kg (1884 lb)

Aviatik C.I (Lo) Series 114 and 214

  Lohner was given a contract for 50 Aviatik C.I biplanes, drawn down from an open order for 72 aircraft signed on 27 January 1917. Work began in April. The first airframe was static tested at Aspern in July, releasing the type for delivery in August 1917. Virtually all aircraft left the factory without armament, which was installed at the Front. The contract had scheduled 24 Aviatik C.I (Lo) series 114 aircraft powered by the 185 hp Daimler engine and 26 series 214 aircraft powered by the 200 hp Daimler. However a critical shortage of the latter engine forced a change in production quantities to 32 series 114 aircraft (114.01 to 114.32) and 18 series 214 aircraft (214.01 to 214.18). Even so, eight series 214 machines were accepted without engines. In the field, aircraft 214.06, 14, 15, and 18 were fitted with used 185 hp Daimler engines.
  As of October 1917, the series 114 was supplied singly to Fliks 2/D, 4/D, 8/D, 10/F, 16/D, 19/D, 23/D, 27/F, 46/D, 47/D, 49/D, 50/D, 53/D, 57/F, and 58/D, but were soon replaced by other aircraft. The series 214 formed the first equipment of Fliks 22/D, 38/D, 40/P, 49/D, and 52/D. Series 114 and 214 were flown as trainers by Fleks 6 and 8, and the Feldfliegerschule Campoformido. The Lohner-built Aviatik C.I machines did not gain the full confidence of frontline personnel. In general, the Aviatik-built version was preferred because of superior workmanship and performance. Some series 114 and 214 aircraft were modified as single-seat, photoreconnaissance fighters by covering the rear seat and replacing the observer with a sack of sand to balance the aircraft. The frontline inventory of 1 August 1918 listed eleven Aviatik C.I (Lo) series 114 and five series 214 aircraft.

Aviatik C.I(Lo) Series 114 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 8.40 m |27.56 ft)
Span Lower 8.40 m (27.56 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.60m (5.25 ft)
Total Wing Area 24.8 sq m (267 sq ft)
General: Length 7.68 m (25.20 ft)
Height 2.96 m (9.71 ft)
Track 1.80 m (5.91 ft)
Empty Weight 650 kg (1433 lb)
Loaded Weight 990 kg (2183 lb)
Climb: 1000m (3,281 ft) in 3 min 50 sec
3000m (9,843 ft) in 17 min 12 sec

Aviatik C.I(Lo) Series 214 Specifications
Engine: 200 hp Daimler
Wing: Span Upper 8.40 m |27.56 ft)
Span Lower 8.40 m (27.56 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.60 m (5.25 ft)
General: Length 7.68 m (25.20 ft)
Height 2.96 m (9.71 ft)
Empty Weight 732 kg (1614 lb)
Loaded Weight 1045 kg (2304 lb)
Maximum Speed: 178 km/hr (110.5 mph)
Climb: 1000m |3,281 ft) in 3 min 46 sec
3000m (9,843 ft) in 14 min 5 sec


Aviatik 30.14 (new), 30.15, and 30.16

  Based on the design experience gained with the 30.14 prototype, Aviatik engineers proposed an improved fighter (30.19) and a derivative two-seat biplane. On 26 September 1916, Flars ordered three, two-seat prototypes numbered 30.14, 30.15, and 30.16. (After the destruction of the 30.14 fighter, the number was re-assigned). The 30.14 reconnaissance prototype, powered by a 185 hp Daimler engine, came to Aspern for flight tests on 26 November. It was similar to the production version (designated C.I) except that the upper wing consisted of two panels and a separate center section. Details regarding the flight trials are lacking but the severe 1917 winter certainly retarded progress. On 9 February 1917, the 30.14 broke its back in a collision with a trainer on the ground. A new fuselage was provided. When Uzelac flew the machine on 22 February, he was impressed by "its fighter-like handling characteristics" and instructed Flars to push the development program with all possible speed.
  Construction of the 30.15 prototype began in October 1916 and it appeared at Aspern in January 1917. The overall flight performance was reported excellent. The fuselage was damaged on 23 January when the tail skid collapsed while landing. Aviatik chief pilot, Stabsfeldwebel Fritz Wurbel was unable to fly the repaired machine on 10 February because it had been sabotaged. The elevator had been incorrectly wired and the tires slashed. The 30.15 was released for evaluation by Flars pilots on 13 February 1917.
  During the first load test on 22 February, the rear spar of the third prototype, 30.16, collapsed at a 3.7 load factor. A strengthened wing, tested on 5 March, again failed. The upper wing, re-designed as a single structure, was tested on 23 March 1917 with satisfactory results.
  On 29 April 1917, Uzelac demanded top priority to bring the promising two-seater, now designated C.l, into production. The 30.15 and 30.16 prototypes were repaired, brought up to production standard, and entered LFT service under the designations Aviatik C.l 37.02 and 37.03. Some sources claim that prototype 30.14 became 37.01, but this is inconsistent with the fact that the 30.14 prototype was written-off on 21 March 1918 as was the 37.01 on 22 April 1918.

Aviatik 30.15 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 8.40 m (27.56 ft)
Chord Upper 1.75 m (5.74 ft)
General: Length 6.83 m (22.41 ft)
Track 1.80 m (5.91 ft)


Aviatik C.I Series 37 and 137

  According to Graf Sternberg, if Berg's two-seater proposal of 8 June 1916 had been given priority instead of the Knoller program, the Aviatik C.I could have been operational in the autumn of 1916 and not, as it happened, a year later. Only after Uzelac's intervention in August 1916 was Aviatik allowed to proceed with construction of three C.I prototypes (30.14-30.16). When these were test flown, there was little doubt that Aviatik had produced a very fine aircraft.
  In March 1917, Flars ordered 96 Aviatik C.I aircraft (including three prototypes 37.01-37.03 (ex-30.15, 30.16, and possibly 30.14 new) and four pre-production machines for evaluation (37.04-37.07, delivered in March and April 1917). Provided the tests were successful, Aviatik was to deliver 49 C.I series 37, numbered 37.08 to 37.56, powered by a 185 hp Daimler engine and 40 C.I series 137, numbered 137.01 to 137.40, powered by a 200 hp Daimler engine. Oberleutnant Oskar Fekete, an expert test pilot who flew the pre-production 37.04 under ideal conditions at Wiener-Neustadt, wrote on 31 March 1917:
  An exceedingly easy-to-fly machine. Stability in all axes very good. Reacts fully to the rudder. Very good climb rate and great speed. Glide flat and pleasant. Landing easy. View in all directions very good. An ideal observation type, suited to mountainous terrain and small airfields.
  On 29 April 1917, Uzelac requested top priority for the C.I and prepared for license manufacture at Lohner, Lloyd, MAG, and WKF that raised the production total to 255 C.I aircraft.
  Prior to general squadron release, a few machines were assigned to Flek 6 for instructional purposes and to Flik 19 for frontline evaluation. Flik 19 soon reported structural problems (12 May 1917), causing Uzelac to halt production and ground the C.I biplanes for inspection and modification. The structural report issued on 11 July 1917 specified strengthening the engine bearers, aileron supports, center-section struts, tail skid, control surfaces, wing leading edges, and lower-wing attachment fixtures. Given the added weight of the modifications, the C.I failed to achieve the contractual climb rate, but the penalty was waived since the required speed was exceeded. When the Aviatik C.I appeared at the Front in August 1917, aircrew reaction was unexpectedly negative. Both Flik 23 and 46 found the C.I unsatisfactory because of the fragile airframe and sloppy workmanship. Flik 46, perceiving the C.I "impossible as a two-seater," changed 37.46 into a single-seat fighter by installing twin synchronized machine guns, decking over the rear cockpit and removing 30 kg (66 lb) surplus equipment. The C.I single-seat conversion, especially the photo-reconnaissance version, was to become very popular in 1918.
  Unfavorable assessments continued. In October 1917, Flik 32 reported the C.I as unsuitable for photo work because aircraft instability caused photos to blur. Complaints were received about the cramped observer's cockpit and the inability to carry cameras larger than 30cm focal length. Flik 34 wrote in October 1917 that the C.I, greeted with high hopes because of its performance, was soon grounded because of structural problems. Even after strengthening, the squadron "had little confidence in the type." To place these statements into the proper perspective, it must be remembered that pilots, accustomed to flying heavy, stable aircraft such as the Brandenburg C.I, found the sensitivity of the Aviatik C.I strange and disconcerting. With time frontline personnel came to appreciate its qualities. Pilot Philipp Vacano recalled that "the C.I was light on the controls and had to be flown with a certain touch. Unfortunately, not every pilot had it. The C.I responded to small gusts and even the motion of an observer swinging the machine gun would induce oscillations." Max Hesse, in his memoirs, reckoned the C.I was "suitable only for daredevils." The wheel control was cumbersome but a stick control was never fitted. The unusual rudder pedals - similar to automobile pedals - prompted so much criticism that they were replaced by a customary rudder bar beginning with aircraft 37.25.
  Armament consisted of a fixed machine gun mounted on the center-section, firing at a 15 degree angle over the propeller, and a gun for the observer. In general, the machine guns were not installed at the factory due to the shortage of guns and interrupter mechanisms. In June 1917, aircraft 37.21 was sent to Fischamend for installation of a wooden rotating turret that became production standard beginning with aircraft 37.49. Aircraft 37.13 was tested with twin, forward-firing machine guns.
  The Aviatik C.I series 37 saw operational service on the Italian Front, where it was assigned to Fliks 17/D, 21/D, 24/F, and 48/D in the South Tirol and to Fliks 2/D, 5/D, 12/Rb, 19/D, 22/D, 23/D, 32, 34/D, 35/D, 46/P, and 58/D on the Isonzo Front. In the spring of 1918, the C.I series 37 was slowly being replaced by aircraft of greater range, durability, and load-carrying ability.

Aviatik C.I Series 37 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 8.40 m (27.56 ft)
Span Lower 8.25 m (27.07 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.70 m (5.58 ft)
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.52 m (4.99 ft)
Stagger 0.36 m (1.18 ft)
Total Wing Area 24.8 sq m (267 sq ft)
General: Length 6.86 m (22.51 ft)
Height 2.26 m (7.41 ft)
Track 1.80 m (5.91 ft)
Empty Weight 653 kg (1440 lb)
Loaded Weight 976 kg (2152 lb)
Maximum Speed: 178 km/hr (111 mph)
Climb: 1000m (3,281 ft) in 3 min 52 sec


Aviatik C.I Series 137

  After aircraft 37.01 was evaluated with a 200 hp Hiero engine, the engine was replaced by a 200 hp Daimler in June 1917. As such the 37.01 became the prototype for the Aviatik C.I series 137. Acceptances began in September 1917 and ran concurrent with the series 37 until June 1918, when the last of 40 C.I series 137 aircraft was accepted. Because fighters were given priority for the 200 hp Daimler engine, most of the series 137 machines were delivered with rebuilt 185 hp Daimler engines, and 13 left the factory without engines due to the engine shortage.
  When the Aviatik C.I series 137 biplanes arrived at the Front in November 1917, aircrews appreciated the good performance but criticized the shoddy workmanship. Such a lightly-designed aircraft required materials and a level of craftsmanship that Aviatik seemed unable to meet. The rocky airfields encountered on the Italian Front played havoc with the airframe, particularly the plywood-covered fuselage. Responding to aircrew complaints, the fuselage of 137.32 was load tested on 5 January 1918 and corrective measures taken. As a two-seater, the C.I series 137 saw operational service with Fliks 5/D, 17/D, 21/D, 23/D, 27/D, 39/D, 47/D, 49/F, 50/D, 53/D, 58/D, 59/D, and 73/D.


Aviatik C.I Single-Seat Conversion

  The fact that Flik 23 and 46/F had obtained good results with the single-seat fighter conversion of the C.I did not escape the attention of the LFT. With only one crew member aboard, the C.I was judged equal to the Aviatik D.I. By converting the C.I, Fliks were able to provide their own fighter protection when none was available from fighter units or supply parks. The single-seat photo-reconnaissance fighter could penetrate enemy airspace and, if intercepted, engage Allied fighters on near-equal terms. Conversion was easy. The machine gun ring was removed and correct ballast placed in the enclosed observer's cockpit. For photographic missions, a 50 or 70cm (20-28 in) focal-length camera was installed, provided with a remote plate-changing device actuated by the pilot. At least 16 C.I series 37 (37.09, 13, 17, 22, 23, 27, 34, 35, 36, 43, 44, 45, 46, 48, and 54) and 12 series 137 (137.02, 04, 14, 20, 21, 26, 28, 30, 31, 35, 36, and 37) were converted to photoreconnaissance fighters in 1917-1918.
  On 12 July 1918, the LFT restricted the Aviatik C.I to the single-seat photo-reconnaissance role or to training duties at Fliks for advanced fighter instruction. The Aviatik C.I had arrived too late and was too failure-prone to achieve its full potential as an all-round reconnaissance aircraft. But as a photo-reconnaissance fighter, the C.I, especially the more reliable license machines, served admirably until the war's end.


Aviatik C.I License Production

  The success of the Aviatik C.I led Flars to place license-production orders with Lloyd, Lohner, MAG and WKF for a total of 255 aircraft. The individual series are covered in detail in the appropriate chapters:
Company Series No. Engine Number Ordered Number at Front on 1 August 1918
Lohner 114.01-32 185 Dm 32 11
Lohner 214.01-18 200 Dm 18 5
Aviatik 37.01-56 185 Dm 56 25
Aviatik 137.01-40 200 Dm 40 13
Lloyd 47.01-45 185 Dm(MAG) 45 26
WKF 83.01-40 185 Dm 40 25
MAG 91.01-24 185 Dm(MAG) 24 24
Total 255 129


Aviatik C.I(Ll) Series 47

  In April 1917, Lloyd was ordered to prepare for the license production of 45 Aviatik C.I reconnaissance biplanes as part of a contract for 96 aircraft signed on 18 January 1917. Parts assembly began in May and the first Aviatik C.I (Lloyd Type JR) left the factory in September 1917. The Aviatik C.I(Ll) were numbered 47.01 to 47.45 and powered by re-built 185 hp Daimler(MAG) engines.
  In November 1917, Lloyd was directed to convert all Aviatik C.I(Ll) biplanes to single-seat fighters and 40 of these were to have photo-reconnaissance equipment installed. Owing to severe supply shortages, all aircraft were accepted unarmed and only 16 (aircraft 47.04, 47.06, 47.07, 47.09-47.13, 47.15, 47.19-47.23, 47.38, and 47.40) had photo equipment installed. Thirteen aircraft were delivered without engines. As it was customary to retain the observer's gun ring, aircraft 47.01 to 47.18 were fitted with a tubing mount and the remainder with a wooden-ring mount.
  Not all Aviatik C.I(Ll) biplanes reached the Front. The April 1918 frontline status report listed 27 C.I series 47 aircraft, of which 11 lacked engines. The Lloyd-built C.I was employed as a fighter by Flik 101/G and as a two-seat reconnaissance machine or photo single-seater by Fliks 17/D, 24/F, and 39/D. Powered by re-built, worn-out engines, the performance had diminished accordingly; consequently in July 1918, the C.I(Ll) series 47 was restricted to training use, of which 24 were on charge as of October 1918. Seventeen Aviatik C.I(Ll) biplanes were offered for sale to Czechoslovakia in April 1920.

Aviatik C.I(Ll) Series 47 Specifications
Engine: 185 hp Daimler (MAG)
Wing: Span Upper 8.40 m (27.56 ft)
Span Lower 8.30 m (27.23 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.65 m (5.41 ft)
Sweepback Lower 1 deg
Gap 1.55 m (5.09 ft)
Stagger 0.36 m (1.18 ft)
Total Wing Area 24 sq m (258 sq ft)
General: Length 7.15 m (23.46 ft)
Height 2.60 m (8.53 ft)
Empty Weight 670 kg (1477 lb)
Loaded Weight 1016 kg (2240 lb)
Maximum Speed: 170 km/hr (106 mph)
Climb: 1000m (3,281 ft) in 4 min 30 sec
2000m (6,562 ft) in 9 min 15 sec
3000m (9,843 ft) in 17 min 50 sec


Aviatik C.I(WKF) Series 83

  To follow the Knoller and Lloyd production, Flars signed an open contract on 18 January 1917, for 72 Aviatik biplanes and in April specified the initial production batch to consist of 16 Aviatik C.I(WKF) series 83 powered by the 185 hp Daimler engine and 24 series 183 powered by the 200 hp Daimler engine. Due to the shortage of 200 hp engines, the series 183 airframes under construction were fitted with 185 hp engines and redesignated accordingly. Consequently, WKF delivered a total of 40 Aviatik C.I(WKF), numbered 83.01 to 83.40. WKF was scheduled to begin deliveries in June 1917 with production ending in October. The first aircraft, 83.01, was commissioned on 27 June 1917 but acceptances were delayed to allow structural modifications (same as specified for the Aviatik C.I series 37 in July) to be incorporated by WKF, which may be one reason why the C.I(WKF) acceptances did not begin until February 1918. By then, frontline experience had demonstrated the value of the Aviatik C.I in the single-seat photo-reconnaissance role. In March 1918, forty single-seat conversion kits for the WKF-built C.I were ordered and about twelve aircraft were so modified in the factory. As a result of chronic shortages, many series 83 aircraft were accepted less engine and armament. It was planned to install these in the field. About half the aircraft were armed with a forward-firing synchronized machine gun and a few were armed with the Type II VK gun canister mounted on the upper wing. All machines were provided with a standard observer machine-gun ring.
  The Aviatik C.I(WKF) saw only limited operational service. Seven series 83 were attached to newly-formed Flik 73/D in mid-1918. Although one was lost in combat, the lack of suitable flight personnel, plus rough airfield conditions which damaged many aircraft, led to the type being supplanted by the more rugged Brandenburg C.I. One each of series 83 aircraft was assigned to Fliks 17/D, 23/D, and 27/F for use as a trainer in preparation for arrival of the UFAG C.I. Of the 25 C.I(WKF) biplanes in the field as of 1 April 1918, most appear to have fulfilled an advanced trainer requirement.
  On 31 October 1918, eleven C.I(WKF) series 83 biplanes were in storage and in 1920 two were offered for sale to Czechoslovakia.


Aviatik C.I(MAG) Series 91

  In April 1917, MAG received a letter of intent to build 96 Aviatik C.I and D.I aircraft. The contract was signed on 17 July 1917. The planned production total of 50 Aviatik C.I(MAG) biplanes, powered by the 200 hp Daimler(MAG) engine, was reduced to 24 (numbered 91.01 to 91.24) on 9 October 1917. Delivery was scheduled between 2 and 30 March 1918. The first factory flight (aircraft 91.06) was performed by Antal Feher on 16 February 1918, and military acceptances were completed almost on schedule in April. Aircraft 91.01-91.03, 91.05, 91.09, and 91.10 were delivered as single-seat photo-reconnaissance aircraft. All aircraft were accepted less armament, and aircraft 91.05-91.09 and 91.15-91.19 were delivered without engines.
  In March 1918, the Aviatik C.I(MAG) biplanes were ordered sent to the 6th Army on the Piave Front. Aircraft 91.23 and 91.24 were damaged in transit. There is no record of any frontline employment; rather, on 17 August 1918, aircraft 91.01-91.22 were scheduled for modification into dual-control trainers and dispatched for conversion to the Al-Ma factory in Prag in October. In the postwar strife at least three aircraft, 91.16, 91.17, and 91.18, were used by the 3rd Squadron of the Hungarian Red Airborne Corps.

Aviatik C.I(MAG) Series 91 Specifications
Engine: 200 hp Daimler (MAG)
Wing: Span Upper 8.40 m (27.56 ft)
Span Lower 8.40 m (27.56 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.65 m (5.41 ft)
Gap 1.53 m (5.02 ft)
Stagger 0.36 m (1.18 ft)
Total Wing Area 25.7 sq m (277 sq ft)
General: Length 6.86 m (22.51 ft)
Loaded Weight 1067 kg (2353 lb)
Maximum Speed: 175 km/hr (109 mph)
Climb: 1000m (3,281 ft) in 3 min 38 sec
3000m (9,843 ft) in 15 min 45 sec
5000m (16,405 ft) in 33 min 40 sec

Aviatik D.I (Lo) Series 115 and 315

  Preparations were underway at Lohner in mid-1917 to replace Aviatik C.I production with the Aviatik D.I fighter, of which 93 had been ordered: 21 from the open 27 January 1917 contract and 72 as part of the 17 July 1917 contract. On 18 May 1918, a further 96 D.I were ordered for a total of 189 aircraft, reduced to 165 in September 1918. Production was divided into 89 series 115 fighters (115.01 to 115.89) powered by the 200 hp Daimler engine and 76 series 315 (315.01 to 315.76) by the 225 hp Daimler engine. The first two series 115 fighters were accepted in December 1917, but owing to subzero winter weather the 17 fighters delivered between 10-31 December 1917 were not accepted until March 1918. Forty series 115 fighters and all those over 115.62 had twin machine gun armament installed at the Front. By 31 October 1918, a total of 88 machines had been accepted.
  In May 1918, shortly after the series 115 fighters had reached the Front, five Flik 60/J aircraft experienced wing trailing edge failure: among them Stabsfeldwebel Albin Heidi (115.30 on 11 May 1918), Oberleutnant Fritz Pisko (115.05 on 16 May 1918 and 115.26 on 18 May 1918) and Leutnant von Szabo (115.24 on 19 May 1918). Other squadrons reported similar incidents. Oberleutnant Frank Linke-Crawford, commander of Flik 60/J and a 27-victory ace, complained in mid-May 1918 that "At present I have seven Berg single-seaters (series 115) whose wings tear apart at high speed at great risk to life. Therefore I cannot permit them to be flown against the enemy." To fix the problem, a Lohner production engineer accompanied a repair team to the Front to fix the wings. Investigation showed that Lohner had substituted a lighter rib section and had attached the fabric in a manner different than specified by Aviatik. How this fact escaped the resident Flars inspector is inexplicable. Uzelac ordered the series 115 returned to the factory for wing replacement. Aircraft beginning with 115.66 left the factory in strict compliance with specifications.
  Unfortunately, Uzelac's order came too late. It is indicative of the sense of duty Austro-Hungarian flying personnel showed throughout the war that they continued to fly the dangerous Lohner-built fighters at "great risk to their lives." Ironically, Linke-Crawford was flying aircraft 115.32 during his last combat on 31 July 1918. Eye-witnesses reported that Linke-Crawford, pursued by British fighters, had just levelled out after a high-speed dive and spin when he was seen "throwing papers overboard." This impression is believed to have been given by shreds of fabric tearing from the wing as a result of the violent maneuvers. As he throttled back to nurse his badly-damaged machine home, Linke-Crawford was attacked and shot down.
  Similar reports of failure led to swift if belated action. The Lohner-built machines were grounded or restricted to noncombat duties. On 4 August 1918, the Army High Command ordered the 200 hp Daimler engines removed from aircraft 115.01 to 115.48 and installed in Aviatik D.I series 238 and 284 fighters to replace their 160 hp engines. Fifteen series 115 fighters, fitted with used 185 hp Daimler engines, were assigned to training duties. A handful of newer production machines remained operational with Fliks 14/J, 56/J, 60/J, and 72/J and singly with Fliks 63/J, 73/J, and 74/J. At least eight, modified for photo-reconnaissance work in September 1918, were assigned to Flik 40/P and 70/P, but saw limited employment. Because the Lohner-built fighters engendered universal mistrust and were considered "unsympathetic aircraft," pilots preferred to operate more robustly-built machines whenever possible. No wonder then that only one pilot, (Linke-Crawford) can be found who was credited with a victory while flying a Lohner-built series 115 fighter (115.32)! The series 115, no matter how well constructed, could not outlive its destructive reputation. In 1920, fifteen series 115 fighters (most with numbers below 115.48) were offered for sale to the Czechoslovakian government.

Aviatik D.I(Lo) Series 115 Specifications
Engine: 200 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 7.89 m (25.89 ft)
Chord Upper 1.45 m (4.76. ft)
Chord Lower 1.45 m (4.76 ft)
Total Wing Area 21.7 sq m (233 sq ft)
General: Height 2.50 m (8.20 ft)
Empty Weight 668 kg (1473 lb)
Loaded Weight 798 kg (1760 lb)
Maximum Speed: 185 km/hr (115 mph)
Climb: 1000m (3,281 ft) in 2 min 38 sec
3000m (9,843 ft) in 9 min 52 sec


Aviatik D.I (Lo) Series 315

  By September 1918, series 315 production was in full swing. Records show that only three or four fighters were dispatched from Vienna and it is doubtful if these reached any frontline unit. By 31 October 1918, a total of 22 series 315 fighters had been accepted. Of the remaining 54, half were ready for acceptance and the other half about 50 percent complete. Production had been scheduled to end in December 1918.

Aviatik D.I(Lo) Series 315 Specifications
Engine: 225 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 7.89 m (25.89 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.45 m (4.76 ft)
Total Wing Area 21.7 sq m (233 sq ft)
General: Length 6.80 m (22.31 ft)
Height 2.50 m (8.20 ft)
Empty Weight 638 kg (1407 lb)
Loaded Weight 912 kg (2011 lb)
Climb: 1000m (3,281 ft) in 2 min 47 sec
2000m (6,562 ft) in 6 min 47 sec
3000m (9,843 ft) in 12 min 45 sec
4000m [13,124 ft) in 22 min


Aviatik D.I Series 38

  The Aviatik D.I was the first fighter designed in Austria-Hungary to enter LFT service. It had evolved from the ill-fated 30.14 prototype, followed by the definitive D.I prototypes (30.19-30.21) that made their successful debut in early 1917. Thus began a broad D.I manufacturing program involving six manufacturers that would account for 43 percent of the total fighter acceptances through October 1918. Eager to replace the dangerous Brandenburg D.I, Uzelac urged Aviatik to begin production at once. The first production machine, 38.01, arrived at Aspern for flight tests in April 1917. That month Flars ordered 48, later increased to 72, D.I fighters, numbered 38.01 to 38.72 and powered by the 185 hp Daimler engine. At the time the formal contract was signed on 17 July 1917, two D.I fighters were at the Front and production was entering high gear.
  The first Aviatik D.I fighter, 38.01, was accepted on 3 May 1917. After being inspected and approved by a Flars engineering commission on 12 May, it was sent to Fluggeschwader I (later Flik 101/G) on 15 May 1917 for service evaluation along with the 30.19 prototype. Aircraft 38.02 went to Flik 12 where it was flown by Hauptmann Godwin Brumowski (17 & 26 June). The first Aviatik D.I victory, an Italian Nieuport, was credited to the CO of Fluggeschwader I, Hauptmann Karl Sabeditsch (flying 38.01) on 20 August 1917. In June 1917, D.I assembly (24 aircraft nearing completion) was slowed in order to analyze the airframe to determine potential weak spots such as had appeared during the Aviatik C.I's service introduction. Taking no chances, Flars directed that the D.I be strengthened in a manner similar to the C.I. In August-September 1917, small numbers of the new Aviatik D.I began to reach Fliks 4, 23, 28, 35, 41/J, and 42/J. Unlike the C.I, initial squadron reaction was generally positive. Pilots praised the performance and regarded the D.I as having "the best climb rate of any fighter without sacrificing maneuverability. The flight characteristics exceed those of all contemporary fighters." In fact, test pilot Antal Feher, flying 38.03 on 12 June 1917, reached a speed of 197 km/h (122 mph), some 10 km/h (6 mph) faster than the new 200 hp Albatros D.III(Oef) series 153 fighter.
  But these fine attributes were negated by the lack of a satisfactory machine gun synchronization mechanism. The wing-mounted machine gun, fixed at a 15 degree angle to fire over the propeller, was reported to be "utterly ineffective." Pilots discovered that it was almost impossible to attack an opponent unless the aircraft was in a dive, thereby losing altitude and leaving the pilot at a disadvantage. Even so, a few victories were recorded by skillful pilots. In addition to Sabeditsch, known are Offizierstellvertreter Friedrich Hefty of Flik 42/J and Feldwebel Karl Benko of Flik 28, who were credited with a victory each on 27 and 29 October 1917, respectively. The D.I series 38 also was operational with Fliks 32, 47, 53/D, and 58/D, and went on to serve as a fighter-trainer with Fliks 63/J, 68/J, and 74/J.
  When Uzelac learned in November 1917 that the D.I was being delivered without gun synchronization some six months after entering service, he ordered Aviatik, who had been working on the problem, to demonstrate progress to date. As of December, twin synchronized machine guns were installed, but at the expense of accessibility, for the guns were mounted alongside the engine out of the pilot's reach in event of a stoppage. Work was under way to modify the airframe for placing the guns in front of the pilot. Tests in mid-January 1918 were successful and beginning in June-July 1918, all D.I fighters were delivered with accessible guns. The problems of cartridge lubrication spray and restricted frontal visibility made it necessary to install the aiming sight alongside the engine. The pilot was required to lean to one side to aim the guns. Consequently, much attention was given to improving visibility, especially reducing the size of the large nose radiator. Many radiator shapes were tested but none proved entirely successful. Nor did the thin wing section permit installation of an airfoil radiator. Throughout the production cycle, and in seeming random fashion, D.I fighters left the factory with either the original nose radiator, a twin side-mounted type, or a block radiator mounted on the upper-wing leading edge.
  It is difficult to understand why Berg, himself a pilot, designed the D.I with such an awkward steering-wheel control. Flik 42/J reported the control as "unsympathetic for fighter pilots, especially difficult to fly in gusty weather." When the more-powerful D.I series 138 appeared still fitted with a control wheel, the outspoken commander of Flik 61/J, Oberleutnant Ernst Strohschneider, vented his displeasure in January 1918 by writing that the fighter "was obviously designed by someone who had never flown." In truth, the wheel control was not all that bad since the light and nimble D.I responded easily to small control movements, but in deference to popular demand it was soon replaced by a stick control.
  Produced in four series, the Aviatik D.I remained in production until the war's end. Being structurally identical, one series did not follow another as might be expected; rather all four were produced in parallel according to engine availability, which had difficulty keeping pace with aircraft output. The D.I was ideally suited for license manufacture because of its relatively simple design. Using wood and plywood with a minimum of complex metalwork, the airframe was ideal for semi-skilled woodworkers to build. In April 1917, Lohner, MAG, and Thone & Fiala received large license orders, followed by Lloyd and WKF in early 1918. As of 31 October 1918 (the last month for which acceptance figures are available), a total of 677 D.I fighters had been accepted. Had production ended as scheduled in December 1918, a grand total of 983 D.I fighters would have been delivered, as shown in the nearby chart. Information regarding the various license-built D.I fighters can be found in the appropriate chapters.

Aviatik D.I Series 38 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 7.89 m (25.89 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.45 m (4.76 ft)
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.35 m (4.43 ft)
Stagger 0.26 m (0.85 ft)
Total Wing Area 20.3 sq m (219 sq ft)
General: Length 6.86 m (22.51 ft)
Height 2.92 m (9.58 ft)
Track 1.80 m (5.91 ft)
Empty Weight 580 kg (1279 lb)
Loaded Weight 850 kg (1874 lb)
Maximum Speed: 187 km/hr (116 mph|
Climb: 1000m (3,281 ft) in 2 min 18 sec
3000m (9,843 ft) in 8 min 4 sec
5000m (16,405 ft) in 20 min 18 sec


Aviatik D.I Series 138

  The most popular Aviatik D.I version was the series 138 powered by the 200 hp Daimler engine. Pressed by the LFT to increase the engine power, Austro-Daimler brought out the 200 hp Daimler engine in early 1917. The power rating was increased by raising the compression ratio and the use of four valves per cylinder. British engineers who tested a captured Daimler engine (taken from aircraft 138.27) reported that it "possessed more originality in design than the majority of enemy engines up to the present time" (July 1918). As part of the 17 July 1917 open contract, 88 D.I series 138 fighters were ordered. These were numbered 138.01 to 138.64 and 138.97 to 138.120 (the numbers 138.65 to 138.96 remained unused). The first aircraft was accepted in September 1917 and the last in November 1918 at the factory by the resident inspecting officer.
  When the 200 hp Aviatik D.I fighters arrived at frontline units beginning in October 1917, they were met with the same mix of enthusiasm and criticism as had greeted the D.I series 38. Flik 42/J reported in January 1918 that the Aviatik was faster, possessed a superior rate of climb, and was more maneuverable than the Albatros D.III(Oef), but that the visibility and armament were unsatisfactory. With respect to climb and speed, Flik 52/D assessed the series 138 as equal to the Sopwith Camel. In February 1918, aircraft 138.98 and 138.114 were dispatched to the German test center at Adlershof for comparison with German fighters. Idflieg (Inspectorate of Aviation Troops) reported that the D.I demonstrated better climb and speed than the Albatros D.V but was less maneuverable.
  A British technical evaluation of a captured D.I (138.27, enemy aircraft number AG 6, flown by Korporal Andreas Kulscar of Flik 4) provides some insight into the Aviatik design practice. The inspection appraisal stated that "everything had been designed to meet the requirements of easy production; everything being kept simple as possible to this end. This does not mean workmanship is inferior. As a matter of fact, the workmanship is very good generally speaking, although the finish may be here and there of a slightly less polished order than is found on some machines." The wings and airframe were of simple construction, but of a "simplicity which does not result in scamped workmanship and hurried finish but which bears evidence of careful design, with ease of production always kept in mind." The timber employed for the wings was of excellent quality, better than that found in the average German machine. The simple fittings combined high strength with light weight. Welding was used to a much smaller extent as compared to German practice. The tailplanes were constructed of large diameter steel tubing, but were single, whereas many German machines used two small-diameter tubes to form a rib.
  The wing was unusual in that the rib section had a pronounced reflex curvature towards the trailing edge and the rear third was remarkably narrow. This feature, introduced by Professor Knoller, was said to reduce the center of pressure travel and result in improved longitudinal stability. But the aerodynamic advantages gained were, to some extent, negated by the danger of fatigue failure caused by the constant inflight flexing of the narrow trailing section. In fact, such failures were a common and sometimes fatal occurrence. In July 1918, Flik 72/J reported that "the wing strength is insufficient. Rib failures have occurred in both wings, causing relatively many accidents including two fatalities." Similar sentiments were voiced by Flik 74/J, noting that the upper wing on the exhaust side was especially vulnerable. The squadron had lost three Aviatik D.I fighters due to wing failure. In response, Berg designed a wing with a smaller chord and additional ribs that reduced the rib spacing by half. Although series 38, 138 and 238 fighters with the new wings were leaving the Aviatik factory in July 1918, it appears that the original wings continued in production, possibly to use up existing stocks. In June 1918, fifteen D.I fighters (38.61, 138.61-63 and 238.56-66) were fitted with a shortened and specially reinforced lower wing that was favorably received by field formations. It is not known if this modification was adopted by the license manufacturers. Notwithstanding the wing reinforcement, the Aviatik D.I continued to have a reputation for being fragile, leading most pilots to prefer the Albatros D.III(Oef) in spite of the D.I's better performance.
  As shown in the accompanying photographs, three types of radiators (nose, side, and leading edge) were employed on Aviatik D.I production aircraft. Apparently these were randomly installed as they became available. The radiators were manufactured by Erenyi, Weich, Windhoff, and Hirschfelder. A number of experimental radiator designs were tested in hopes of improving forward visibility.
  D.I series 138 fighter production spanned a fifteen-month period during which output was geared to the availability of the 200 hp engine. It was supplied to fighter squadrons such as Fliks 14/J, 42/J, 51/J, 56/J, 60/J, 63/J, 68/J, 72/J, and 74/J and in single examples to Fliks 4/D, 15/F, 19/F, 23/D, 28/D, 34/D, 46/F, 53/D, 54/D, 57/F, 58/F, 73/D, and 101/G. As of July 1918, a few served with Flik 37/P as photo-reconnaissance fighters and as trainers with Fleks 6, 19, and the two field flying schools. On 1 August 1918, forty-eight series 138 fighters were serving with frontline squadrons.

Aviatik D.I Series 138 Specifications
Engine: 200 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 7.89 m (25.89 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.45 m (4.76 ft)
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.35 m (4.43 ft)
Stagger 0.26 m (0.85 ft)
Total Wing Area 20.3 sq m (219 sq ft)
General: Length 6.86 m (22.51 ft)
Height 2.92 m (9.58 ft)
Track 1.80 m (5.91 ft)
Maximum Speed: 195 km/hr (121 mph)
Climb: 1000m (3,281 ft) in 1 min 42 sec
2000m (6,562 ft) in 4 min 30 sec
3000m (9,843 ft) in 7 min 36 sec
4000m (13,124 ft) in 12 min 10 sec
5000m (16,405 ft) in 16 min 26 sec
6000m (19,686 ft) in 26 min


Aviatik D.I Series 238

  The chronic shortage of high-powered engines set the stage for the next version of the Aviatik D.I fighter. Because ample stocks of new and reconditioned 160 hp Daimler engines were on hand, Flars tested an Aviatik D.I powered by that engine in December 1917. It was concluded that the combination was capable of attaining acceptable performance for operational service and was approved for production accordingly. The 160 hp Aviatik D.I series 238 acceptances began in January 1918 and ended in August 1918 when the last of 120 fighters was accepted. The serial numbers assigned were 238.01 to 238.90 and 238.105 to 238.134 (the numbers 238.91 to 238.104 remained unused). At least 20 series 238 fighters were accepted without engines. Armament consisted of twin synchronized machine guns but some 50 fighters were delivered unarmed due to the gun shortage. A few series 238 fighters were fitted with redesigned, all-plywood tail surfaces and ailerons, but the number built is unknown. In August 1918, Flik 1 reported that the wooden parts tended to warp out of shape and, being heavier, impeded maneuverability.
  The introduction of the retrograde D.I series 238 fighter in April-May 1918 triggered universal condemnation by Flik pilots. Flik 6/F complained in May 1918 that the underpowered fighter was too slow to intercept Allied observation machines. The series 238 was regarded as adequate for close-escort missions by Flik 23/D but useless in an offensive role and inferior to Allied fighters. Because pilots were unwilling to fly the underpowered D.I, a few resourceful Fliks installed more powerful engines. For instance, Flik 6/F reported no trouble installing 185 hp Daimler engines taken from wrecked aircraft or scrounged from rear-area depots. On 12 July 1918, the LFT ordered the replacement of all 160 hp engines in the series 238 by new or used 200 hp engines but only a few conversions were made. Those aircraft not used as trainers languished for months in storage until engines could be found.
  The D.I series 238 (some powered by 185 or 200 hp engines) was flown as a fighter by Fliks 1/J, 6/F, 13/J, 23/D, 28/D, and 64/F. The type served as an advanced trainer in Fliks 14/J, 43/J, 55/], 56/J, 72/J, 74/J, and with Flek 6 and the two field flying schools. Several series 238 were used as photoreconnaissance fighters by Fliks 37/P, 40/P, and 46/P. On 1 August 1918, eighty-nine Aviatik D.I series 238 fighters were carried in the frontline inventory.

Aviatik D.I Series 238 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 8.00 m |26.25 ft)
Span Lower 7.89 m (25.89 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.45 m (4.76 ft|
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.35 m (4.43 ft)
Stagger 0.26 m (0.85 ft)
Total Wing Area 20.3 sq m (219 sq ft)
General: Length 6.86 m (22.51 ft)
Height 2.92 m (9.58 ft)
Track 1.80 m (5.91 ft)
Maximum Speed: 192 km/hr (119 mph)
Climb: 1000m (3,281 ft) in 2 min 6 sec
2000m (6,562 ft) in 5 min 50 sec
3000m (9,843 ft) in 10 min 12 sec
4000m (13,124 ft) in 15 min 24 sec
5000m (16,405 ft) in 21 min 34 sec


Aviatik D.I Series 338

  By the middle of 1918, output of the new 225 hp Daimler engine had reached a level sufficient to supply two production fighters, the Albatros D.III(Oef) series 253 and the Aviatik D.I series 338. Contracts for a total of 294 Aviatik D.I fighters powered by the 225 hp engine were awarded to Aviatik, Lohner, Lloyd and WKF. These aircraft had strengthened wings and engine bearers, and were armed with twin guns mounted at eye level.
  As part of the contract dated 18 May 1918, Aviatik built a pre-production batch of eight D.I series 338 fighters for evaluation. These were numbered 338.01 to 338.08. Shortly thereafter, Flars ordered 100 production fighters numbered 338.21 to 338.120 (numbers 338.09 to 338.20 remained unused). The pre-production machines arrived at Aspern in June-July 1918 for flight trials. Engine cooling posed a vexing problem. The nose radiator originally fitted to aircraft 338.01 was replaced by twin Hefa side radiators to improve cooling efficiency and forward visibility. Various other side radiators and an Oefam airfoil radiator (tested in aircraft 338.07) were rejected in favor of a block radiator mounted on the upper wing leading edge which became the production standard.
  Two fighters, 338.03 and 338.04, participated in the Fighter Evaluation held on 9-13 July at Aspern. The climb trials performed with aircraft 338.03 were interrupted when the side radiators began to boil over at altitude, but enough data was obtained to demonstrate a remarkable climb rate, second to none. Tested against a captured Sopwith Camel, aircraft 338.06 was faster and showed equal maneuverability with ability to perform sharp turns without altitude loss. In August 1918, aircraft 338.01 and 338.02 were dispatched to Flik 1/J at Igalo for service trials. Here take-off for interception occurred only after enemy aircraft were positively reported or visually sighted. Since it was a task suitable "only for the most rapid climbing and fastest fighter," the fast-climbing D.I series 338 was the ideal aircraft. Flik 1/J commander Oberleutnant Bela Macourek and Offizierstellvertreter Julius Arigi were both credited with two victories while flying a series 338 fighter. Production fighters began to reach the Front in September 1918, but only very few saw combat service in the waning days of the war.
  After the crash of aircraft 338.89 which killed Aviatik test pilot Feldwebel Franz Tordik on 16 October 1918, investigation discovered a faulty aileron-pulley support. On 29 October appropriate modifications were ordered on the 34 completed fighters: 338.01 to 338.08, 338.21 to 338.35 and 338.86 to 338.96 and those in production. The reasons for the non-consecutive production run is not known. At the war's end, the resident inspection officer accepted 27 completed series 338 fighters at the factory; the remaining 23 were almost complete. Series 338 production was scheduled to end in December 1918.
  Postwar plans calling for the Aviatik D.I series 338 to equip the Austrian air arm were forbidden by the treaty stipulations. Acceding to Czechoslovakian demands, 24 series 338 fighters and ancillary equipment were loaded on freight cars for shipment in December 1918. But the Austrian demobilization office did not grant an export permit until mid-January 1919. By then the fighters, damaged by weather exposure and theft, had only scrap value.

Aviatik D.I Series 338 Specifications
Engine: 225 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 7.89 m (25.89 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.45 m (4.76 ft)
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.35 m (4.43 ft)
Stagger 0.26 m (0.85 ft)
Total Wing Area 20.3 sq m [219 sq ft)
General: Length 6.86 m (22.51 ft)
Height 2.92 m (9.58 ft)
Track 1.80 m (5.91 ft)
Climb: 1000m (3,281 ft) in 1 min 59 sec
2000m (6,562 ft) in 4 min 12 sec
3000m (9,843 ft) in 7 min 30 sec
4000m (13,124 ft) in 12 min
5000m (16,405 ft) in 16 min 24 sec
6000m (19,686 ft) in 27 min 30 sec


Aviatik D.I(Ll) Series 48, 248 and 348

  License production of the Aviatik D.I(Ll), under way at Lloyd before the formal contract was signed on 18 May 1918, comprised 100 fighters in the following series:
Quantity Series Number Engine
10 48.01-10 185 hp Daimler(MAG)
20 248.01-20 160 hp Daimler(MAG)
70 348.01-70 225 hp Daimler(MAG)
  All Aviatik D.I(Ll) series 48 and 248 fighters left the factory modified to receive cameras, etc., for photoreconnaissance work. None had machine guns installed. Although scheduled to receive re-built engines - some taken from retired Aviatik C.I(Ll) machines - aircraft 248.04-248.18 and 248.20 were delivered without engines. The series 48 and 248 fighters were dispatched to Flek 6 in Wiener-Neustadt and placed in storage. Subsequently, a few were flown as trainers or assigned to home defense duties in August 1918. Twenty eight were offered for sale to Czechoslovakia in 1920.
  The first Aviatik D.I(Ll) series 348 fighter was accepted in September 1918. On 31 October 1918, the remaining 69 series 348 fighters were reported completed and awaiting acceptance at Aszod but never delivered to the LFT. A handful were taken over and flown by the Hungarian air service. Aircraft 348.45, 348.46 and 348.49 were attached to the 4th Squadron of the Hungarian Red Airborne Corps at Gyor in April 1919. Hungarian pilot J. Kretz, flying 349.49, shot down a Czech Lebed XII two-seater over Gyor during the postwar fighting. According to Hungarian sources, some D.I(Ll) series 348 fighters were deployed for coastal defense and a few were captured by Italian or Yugoslav troops. As late as 1942, the fuselage of 348.61 was on display in the Hungarian War Museum in Budapest.


WKF 80.08

  This prototype has been identified as an Aviatik D.I built by WKF. As was customary at the time, a production airframe (possibly 84.01) was assigned a prototype number for purposes of engineering inspection and flight evaluation before being given a standard series number. The 80.08 prototype, powered by a 185 hp Daimler engine, was recorded at Aspern on 27 May 1918.


Aviatik D.I(WKF) Series 84, 184, 284, and 384

  WKF became one of the five companies to build the Aviatik D.I under license in July 1917, when Flars placed an order for 48 Aviatik D.I(WKF) fighters, followed by a contract for 50 more on 10 May 1918. In mid-1918, when the original production batches were re-numbered according to engine availability, the production break-down was as follows:
Qty Serial No. Engine Order Date First Acceptance
10 84.01-10 185 Dm 10 May 1918 September 1918
24 184.01-24 200 Dm July 1917 May 1918
24 284.01-24 160 Dm July 1917 May 1918
40 384.01-40 225 Dm 10 May 1918 August 1918
  As was the case with the Aviatik C.I(WKF), the acceptances commenced almost a year after the order was placed. About half the fighters were accepted without engines and the remainder left the factory fitted with reconditioned engines. Records show of the total (45) accepted through October 1918, only six left the factory with machine guns installed.


Aviatik D.I(WKF) Series 84

  The Aviatik D.I(WKF) series 84.01 to 84.10 were intended (and possibly specially equipped) as advanced, single-seat trainers. It is possible that a few served in that capacity with Flek 6 in September-October 1918. All ten survived the war and were in storage awaiting disposal in March 1919. Eight were offered for sale to the Czechoslovakian government in 1920.


Aviatik D.I(WKF) Series 184

  Of the 24 ordered, only a single D.I(WKF) fighter (184.01) was accepted prior to 31 October 1918. It joined Flik 72/J in June 1918. At the war's end, 23 series 184 airframes (numbered 184.02 to 184.24), virtually completed and scheduled for delivery in November, were provisionally accepted by the resident Flars representative. The airframes appear to have been scrapped since they do not figure in the postwar disposal records.


Aviatik D.I(WKF) Series 284

  All D.I(WKF) series 284.01 to 284.24 were accepted prior to September 1918. Confusion exists because WKF completed 24 additional series 284 airframes, originally numbered 284.25 to 284.48. Prior to delivery, Flars decreed that these were to receive the 225 hp Daimler engine and be re-designated series 384. However, before implementation at least 35 series 284 fighters entered the records when they were assigned to rear-area distribution centers, but only a handful actually reached operational units before the war ended. Known are Flik 14/J in the South Tirol and the two field flying schools. One series 284 fighter saw service with Flik 6 in Albania. On 28 August 1918, six Aviatik D.I(WKF) series 284 were released by the LFT to the Navy, but it is doubtful if the transfer occurred. In 1920, aircraft 284.07, 20, 28, and 31 were offered to the Czechoslovakian government.


Aviatik D.I(WKF) Series 384

  Ten Aviatik fighters powered by 225 hp Daimler engines were accepted as series 384 while still carrying their old numbers (284.25, 27, 28, 29, 31, 32, 37, 39, 42, and 48). However, it appears they never left the factory, for after the war 40 series 384 airframes were counted at the WKF factory in good condition - the last 30 airframes, scheduled for delivery in November and December 1918, having been accepted by the resident Flars officer.


Aviatik D.I(MAG) Series 92

  On 9 October 1917, the total of 46 Aviatik D.I(MAG) fighters, ordered on 17 July 1917, was increased to 72 at the expense of the Aviatik C.I(MAG). In addition another 100 fighters were ordered on 10 May 1918. Acceptances of the fighters, numbered 92.01 to 92.172 and powered by the 200 hp Daimler(MAG) engine, began in April 1918. By 31 October, 121 had been accepted, almost all without armament and some without engines.
  When Flik 72/J on the Piave Front received the first Aviatik D.I(MAG) in August 1918, evaluation flights produced such dismal results that the squadron rejected the type because "...it is impossible to fly this aircraft over the enemy...the wing cellule is even weaker than that of the early Aviatik D.I series 38, 138 and 238 fighters" which had been grounded in July 1918 by the Army Command. The 6th Army Command ordered Flik 72/J pilots to inspect and test the series 92 machines stored at Pordenone. It was found that aircraft below 92.50 had been manufactured according to the old Aviatik D.I drawings. The wing cut-out was missing. When tested in a spin, the lower wing (not the short-span version as in late model Aviatik-built fighters) "always showed breakage." Furthermore, the quality of MAG workmanship was defective and slipshod. Nevertheless, in the summer of 1918 the Aviatik D.I(MAG) became operational in small numbers with Fliks 1/J, 6/F, and 13/J on the Balkan Front and in south Tirol with Fliks 7/J, 20/J, and 23/D. Flik 7/J was unique in that it was the only unit totally composed of MAG-built Aviatik fighters. In September-October at least 42 aircraft were rejected by three Army commands and withdrawn from the Front. On 10 October 1918, Flik 74/J tested aircraft 92.18 fitted with reinforced wing ribs and found that at 150 km/h (93 mph - well below its top speed of 187 km/h - 116 mph) the upper-wing trailing edge and the lower wing vibrated so severely that "...one cannot develop trust in the aircraft."
  Twenty-five Aviatik D.I(MAG) fighters were offered to the Czechoslovakian government in 1920. The Hungarian Red Airborne Corps had in service aircraft 92.83 (later civil register HJ 83), 92.85 (HJ 85), 92.80 (armed with a Gebauer motor machine-gun), 92.106 (HJ 106), 92.107 (HJ 107) and 92.115 (HJ 115). Aircraft 92.148 of the 3rd Squadron that landed in Austria in 1919 was confiscated and returned to Hungary on 28 March 1920. The highest serial number identified in Hungarian postwar records is 92.170.
Aviatik D.I(MAG) Series 92 Specifications
Engine: 200 hp Daimler (MAG)
Wing: Span Upper 8.00 m (26.25 ft)
Span Lower 8.00 m (26.25 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.45 m (4.76 ft)
Gap 1.47 m (4.82 ft)
Stagger 0.18 m (0.59 ft)
Total Wing Area 22.0 sq m (237 sq ft)
General: Length 6.86 m (22.51 ft)
Height 2.55 m (8.37 ft)
Loaded Weight 888 kg (1958 lb)
Maximum Speed: 200 km/hr (124 mph)
Climb: 1000m (3,281ft) in 2 min 15 sec
2000m (6,562 ft) in 5 mm 30 sec
3000m (9,843 ft) in 10 min
4000m (13,124 ft) in 17 mm
5000m (16,405 ft) in 27 min


Aviatik D.I(Th) Series 101 and 201

  At the time when the formal production contract was signed on 21 June 1917, the first Thone & Fiala-built Aviatik D.I airframe was reported two weeks away from structural tests. A total of 60 Aviatik D.I fighters were ordered as follows:
Qty Series Number Engine Order Date
21 101.01-21 200 Dm 21 June 1917
9 201.01-09 185 Dm 21 June 1917
30 101.31-60 200 Dm May 1918
(Aircraft 201.01-03 were renumbered 101.22-24.)
  Initially all Aviatik D.I(Th) fighters were intended for training purposes and consequently had rebuilt engines installed. Flars reported minor quality-control problems in July 1917, but these were quickly overcome and aircraft of superior workmanship were delivered thereafter. The first production machine, 101.01, arrived at Fischamend on 9 November 1917 for machine-gun installation and was returned to Thone & Fiala on 19 December 1917 to serve as a pattern aircraft. Production acceptances began in March 1918. Owing to the machine-gun shortage, only the first 15 aircraft were delivered armed. Through 31 October 1918, a total of 34 Aviatik D.I(Th) fighters was accepted; ten were provisionally accepted after the war and 16 partially-completed airframes were scrapped.
  Twenty series 101 and two series 201 fighters were listed in the 11th Army frontline inventory of 20 August 1918. Records show that the series primarily saw combat service with Flik 31/P as a photo-reconnaissance fighter. The downing of an Italian Hanriot fighter by Leutnant Vjekoslav Tomasic of Flik 31/P on 4 October 1918, flying aircraft 101.05, is the only known victory achieved with this series. Aircraft 101.32 and 101.33, assigned to Flek 6, were later taken over by the Austrian air service.
  The airframe of aircraft 101.37, presently exhibited in the Technical Museum in Vienna, is noteworthy for its excellent craftsmanship. A few years ago, a rotary-engined biplane (Austrian civil registration A 9) was discovered in a barn and identified as the original Aviatik D.I(Th) 101.40 airframe. Now beautifully restored by the Champlin Fighter Museum in Arizona, it is exhibited in its original 1918 appearance.

Aviatik 30.22

  Along with the 30.19 fighter, Berg proposed a high-speed version without wire bracing powered by a 200 hp Daimler engine. The top wing was supported by two diagonal struts and the lower wing was fully cantilevered. On 20 September 1916, Aviatik was permitted to proceed at its own risk with Flars providing technical support. The prototype, consisting of the modified 30.21 airframe, appeared at Aspern on 26 February 1917 under the designation 30.23 but changed to 30.22 in March 1917. Uncertain of structural integrity, Flars carefully checked the stress calculations and subjected the airframe to exacting load tests before proceeding with flight trials. The wing cellule failed the specified load conditions on 13 March; it was reinforced and tested successfully on 23 April 1917.
  The 30.22 first flew on 25 April 1917. Test pilot Feldwebel Tordik reported greater sensitivity than that of the 30.19. But the bottom wing was seen to flex appreciably in flight, causing Aviatik to withdraw the 30.22 for modification. It came to Aspern for further testing on 2 June and was returned to the factory where it was last reported in July 1917. Further data are lacking. The high speed demonstrated by the 30.22 caused Flars to order a small batch of Aviatik D.II series 39 fighters for frontline evaluation.

Aviatik 30.22 Specifications
Engine: 200 hp Daimler
Wing: Span Upper 7.50 m (24.61 ft)
Span Lower 5.20 m (17.06 ft)
Chord Upper 1.55 m (5.09 ft)
Chord Lower 1.55 m (5.09 ft)
Dihedral Upper 0 deg
Dihedral Lower 0 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.45 m (4.76 ft)
Stagger 0.25 m (0.82 ft)
Total Wing Area 19.5 sq m (210 sq ft)
General: Length 6.98 m (22.90 ft)
Height 2.45 m (8.04 ft)
Track 1.80 m (5.91 ft)
Empty Weight 681.5 kg (1503 lb)
Loaded Weight 801.5 kg (1767 lb)
Maximum Speed: 199 km/hr (124 mph)
Climb: 1000m (3,281 ft) in 4 min 56 sec
2000m (6,562 ft) in 11 min 7 sec
3000m (9,843 ft) in 26 min
4000m (13,124 ft) in 41 min


Aviatik 30.38

  The Aviatik 30.38, a production D.II series 39 fighter powered by a 200 hp Hiero engine in place of the standard 200 hp Daimler, participated in the July 1918 Fighter Evaluation for comparison purposes. During the evaluation the 30.38 recorded substantially lower climb rates than the production Aviatik D.II. On 25 September 1918, the 30.38 was at the Aviatik factory undergoing modification. Further information is lacking.

Aviatik 30.38 Specifications
Engine: 200 hp Hiero
General: Empty Weight 655 kg (1444 lb)
Loaded Weight 915 kg (2018 lb)
Climb: 1000m (3,281 ft) in 4 min
2000m (6,562 ft) in 11 min
3000m (9,843 ft) in 18 min 50 sec


Aviatik D.II Series 39 and 339

  Flight tests of the 30.22 "wireless" prototype were sufficiently promising for Flars to order, on 5 December 1917, nine Aviatik D.II "wireless" fighters for further trials followed by a second batch of 10 aircraft on 10 May 1918. A total of 16 D.II fighters were completed, consisting of aircraft 39.01 to 39.11 powered by the 200 hp Daimler engine and D.II 339.01 (ex 39.09) to 339.06 powered by the 225 hp Daimler. The series numbers 139 and 239 were not used. The modest D.II purchase by Flars was solely for engineering and high-speed investigation, including brief frontline evaluation. The D.II was never intended to replace the Aviatik D.I fighter nor was it considered a priority program at any time.
  Aircraft 39.01 and 39.03 made their appearance at Aspern on 10 August 1917, performing flight trials through November. On 3 October 1917, 39.01 attained 217 km/h (135 mph) making it the fastest Austro-Hungarian fighter to date, although the climb rate was below that of the Aviatik D.I series 138. Aircraft 39.02, assigned in February 1918 to the weapons group at Fischamend, was used to test the experimental Elektro machine gun fitted with a British Aldis sight. Subsequently it was tested with the Gebauer motor machine gun. The nose radiator was standard with exception of aircraft 39.10, 39.11, 339.01 and 339.02 that were equipped with Hefa side radiators and aircraft 339.03 and 339.06 with leading-edge wing radiators.
  In February 1918, aircraft 39.01 and 39.03, known as the "U-Berg" type (U = unverspannt = wireless) and armed with twin synchronized machine guns, were assigned to Flik 61/J for service evaluation personally supervised by the commanding officer, Oberleutnant Ernst Strohschneider. The technical report submitted in May 1918 stated that the speed was far greater than that of the Albatros D.III(Oef). This was especially true of 39.03, which had a metal fairing between the fuselage and lower wing to improve airflow. Visibility was just as poor as in the series 138. At full throttle, the propeller wash caused the wing struts to vibrate some 6 to 8 centimeters, causing alarming airframe vibration, particularly in tight turns. Aileron control was sluggish.
  Three "wireless" fighters participated in the July 1918 Fighter Evaluation at Aspern: 339.02 fitted with a four-bladed propeller and armed with the Gebauer motor machine gun, the 30.38 prototype (a D.II airframe powered by a 200 hp Hiero engine) and 339.01 (ex-39.09). Oberleutnant Benno Fiala reported that the 339.01 (equipped with side radiators) had the better visibility that could be enhanced by fitting a top-wing radiator and reducing the engine cowling height. Among the competitors, 339.01 recorded the slowest rate of climb, requiring an additional 12 minutes to reach 5000 meters (16,405 ft) compared to the fastest climber, the Aviatik D.I 338.03. The experimental nature of the D.II program is evident from the fact that the three D.II variants all had different wing areas.
  In July 1918, five D.II fighters (39.04 to 39.08) were dispatched to the Front for service assessment. Aircraft 39.10 and 39.11, equipped as photo-reconnaissance fighters, were assigned to Flik 46/P in September 1918. One D.II series 39 was based at the field flying school Neumarkt. Aircraft 339.03 and 339.06 were dispatched to the 6th Army on the Piave Front in September 1918. It is unlikely that any of the above aircraft saw combat service. The Aviatik D.II, an interesting high-performance project, was not considered for further production according to the August 1918 schedule.

Aviatik D.II Series 39 Specifications
Engine: 200 hp Daimler
Wing: Span Upper 7.50 m (24.61 ft)
Span Lower 5.20 m (17.06 ft)
Chord Upper 1.75 m (5.74 ft)
Chord Lower 1.65 m (5.41 ft)
Total Wing Area 19.5 sq m (210 sq ft)
General: Length 6.98 m (22.90 ft)
Height 2.45 m (8.04 ft)
Track 1.80 m (5.91 ft)
Loaded Weight 845 kg (1863 lb)
Maximum Speed: 217 km/hr (135 mph)
Climb: 1000m (3,281 ft) in 3 min 5 sec
2000m (6,562 ft) in 6 min 2 sec
3000m (9,843 ft) in 10 min 55 sec
4000m (13,124 ft) in 18 min 7 sec

Aviatik D.II 339.01 Specifications
Engine: 225 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Total Wing Area 22.44 sq m (242 sq ft)
General: Length 7.10 m (23.29 ft)
Height 2.60 m (8.53 ft)
Track 1.80 m (5.91 ft)
Empty Weight 668 kg (1473 lb)
Loaded Weight 947 kg (2088 lb)
Climb: 1000m (3,281 ft) in 3 min 39 sec
2000m (6,562 ft) in 7 min 17 sec
3000m (9,843 ft) in 11 min 32 sec
4000m (13,124 ft) in 16 min 54 sec
5000m (16,405 ft) in 28 min 36 sec

Aviatik 30.25

  The development of the 360 hp six-cylinder and 300/350 hp Daimler V-12 engines had reached a stage in mid-1916 that enabled the Flars design department to begin work on a high-performance aircraft using these engines. In September 1916, Aviatik was given the task of building two "Mises-Saliger" prototypes at Esslingen under the direction of Leutnant Saliger. However, on 14 November 1916 the LFT stopped the work and directed Aviatik to concentrate on the C.I and D.I production. The Mises-Saliger project (no Aviatik prototype number had been assigned) was transferred to Lohner on 11 December 1916, where the program continued under the designation Lohner 10.21 and 10.22. Concurrently, Berg had designed a competing biplane powered by a 360 hp Daimler six-cylinder engine. The project study, dated 6 December 1916 and officially numbered 30.25, was evaluated by Flars who declined to support Berg's proposal and the project was dropped.
  Frontline experience had shown that fast, camera-equipped, single-seat fighters could return unharmed with acceptable reconnaissance photographs and, if necessary, engage or evade Allied interceptors. In mid-1917, specifically to meet the photo-fighter requirement, Aviatik modified a C.I airframe (reported as ex-37.41) to carry two synchronized machine guns and a 30cm focal-length camera in lieu of the observer. A parachute was provided for the pilot. The aircraft, designated 30.25 and powered by a 185 hp Daimler engine, was flight tested in September 1917 by Flars test pilot Hauptmann Oskar Fekete, who felt the conversion of extant Aviatik C.I aircraft was easier and less costly than placing a new type into production. The 30.25 was assigned to Flek 6 in Wiener-Neustadt as a single-seat trainer. On 29 November 1917, during a practice flight, the prototype suddenly stood on its nose and trailing a white smoke plume, crashed into the ground and was demolished.

Aviatik 30.25 Specifications
Engine: 185 hp Daimler
Maximum Speed: 186 km/hr (116 mph)
Climb: 1000m (3,281 ft) in 3 min 20 sec
5000m (16,405 ft) in 30 min 30 sec

Aviatik 30.27 and 30.29

  The LFT aircraft specifications for 1918 listed a Type 5 fighter, an ultra-light interceptor powered by a 150 hp rotary engine. This took into account that, as of May 1917, rotary engine production had begun at the Oesterreichische Waffenfabrik AG, Steyr in anticipation of receiving sufficient supplies of Voltol (castor oil substitute) from Germany. A Steyr rotary engine based on the 150 hp Le Rhone was submitted for duration tests in November 1917. It is not generally known that Steyr delivered 35 out of 150 ordered Le Rhone (St) engines through September 1918 and the rest were nearing completion when the war ended.
  Only Aviatik's rotary-engined fighters were flight tested, although several manufacturers had similar fighters under development at the war's end. The drawings for the first Aviatik prototype, 30.27, were completed in January 1918. The prototype arrived at Aspern for flight tests in March. Preliminary trials demonstrated severe wing twist when the ailerons were actuated. The aircraft was re-built with a larger wingspan, longer fuselage and a fully-cowled engine. During trials in May 1918, the modified 30.27 reached a maximum speed of 200 km/h (124 mph), but the climb rate did not meet the LFT criteria.
  The Aviatik 30.29 was similar in all respects to the 30.27. Both aircraft participated in the July 1918 Fighter Evaluation at Aspern. Neither received praise or condemnation and any hope of a favorable critique disappeared when the upper wing of 30.29 failed in flight.
  The manufacturer's drawings, dated March 1918, refer to a version, based on the 30.29 and designated Aviatik D.III, for which series production was contemplated. But Voltol production, sufficient to meet German but not export requirements, thwarted LFT plans to put a rotary-engined interceptor into service. Consequently, interceptor development was accorded low priority. Because "no aircraft were ready," in September 1918 Flars recommended sending the completed Steyr engines to Germany in return for Oberursel rotary engines at a later date.

Aviatik 30.27 Specifications (Open Cowl)
Engine: 150 hp Le Rhone (St)
Wing: Span Upper 6.60 m (21.65 ft)
Span Lower 6.60 m (21.65 ft)
General: Track 1.80m (5.91 ft)
Empty Weight 350 kg (772 lb)
Loaded Weight 600 kg (1323 lb)
Maximum Speed: 200 km/hr (124 mph)
Climb: 1000m (3,281 ft) in 1 min 24 sec
2000m (6,562 ft) in 3 min 6 sec
3000m (9,843 ft) in 7 min 58 sec
4000m (13,124 ft) in 15 min 15 sec
5000m (16,405 ft) in 22 min 32 sec

Aviatik 30.27 Specifications (Closed Cowl)
Engine: 150 hp Le Rhone (St)
Wing: Span Upper 6.82 m (22.38 ft)
Span Lower 6.60 m (21.65 ft)
Chord Upper 1.40 m (4.59 ft)
Chord Lower 1.25 m (4.10 ft)
Maximum Speed: 190 km/hr (118 mph)
Climb: 1000m (3,281 ft) in 2 min 11 sec
2000m (6,562 ft) in 5 min 20 sec
3000m (9,843 ft) in 9 min 18 sec
4000m (13,124 ft) in 18 min 12 sec


Aviatik 30.31 and 30.32

  The Aviatik 30.31 and 30.32 prototypes were similar to the final version of the 30.27 fighter. When it became evident that lack of lubricating oil would prevent the operational use of rotary engines, development work was interrupted and both aircraft were reported stored in "good condition" in the Aviatik hangars in July 1918. At war's end, they were pro-forma accepted to enable Aviatik to receive payment for the aircraft.

Saliger Three-Engine Bomber

  Before he went to Oeffag in early 1917, Ingenieurleutnant Karl Saliger was attached to the Flars construction section. In January 1917, Saliger submitted a proposal for a bomber powered by one 300 hp Daimler V-12 tractor engine and two 200 hp Hiero pusher engines. The empty weight was projected at 2630 kg, the loaded weight at 3470 kg, with a useful load of 390 kg. There appears little doubt that this design was the pattern for the Aviatik 30.23 bomber that was built under government supervision.


Aviatik 30.23

  Flars reported on 29 December 1916 that a new three-engined bomber project would shortly be submitted for approval. The layout and specifications were completed in January 1917 by Ingenieurleutnant Karl Saliger of the Flars bomber group. Powered by one 300 hp Daimler V-12 and two 200/230 hp Hiero pusher engines, the bomber was designed for a crew of three and a bomb load of 440 kg (882 lb). Construction of two prototypes, designated 30.23 and 30.34, was assigned to Aviatik under a cost-plus-fixed-fee contract under Flars supervision. Work on two prototype bombers began in February 1917 with completion scheduled for April-May 1917.
  Progress was slow. In January 1917, Saliger transferred to Oeffag leaving Aviatik engineers, who were already fully occupied with in-house projects, to set the pace. After Saliger's death in July 1917, Berg assumed engineering control, and probably this was the reason that the 30.23 became known as the "Berg" bomber. In June 1917, the 30.23 bomber's fuselage was complete and the flying surfaces were in the process of being covered.
  "Bureaucratic inertia", according to Berg, had delayed engine delivery but, in fact, other programs had been given priority. Consequently, it was not until 7 January 1918 that the 30.23 bomber was completed. Ground trials commenced on 6 March, followed by the maiden flight on 13 March, with satisfactory performance reported. Because the rudder response was felt to be inadequate, three configurations were tested before the correct shape was found. The single wheels were replaced by twin wheels. Finding the proper configuration airscrew to maximize performance proved, as always, extremely time-consuming. Berg wanted to employ reduction gearing to lower propeller revolutions, but Ingenieur Kolin calculated that the power loss would be excessive. Speed and climb trials, on 5 April, 27 April and 24 May 1918, demonstrated results that "compared favorably with contemporary German bombers." On that basis, Flars ordered four additional bombers on 29 May 1918 (see Aviatik G.III series 131).
  On 7 August 1918, contingent on completing a three-hour duration flight, the 30.23 prototype was scheduled to join Flik 102/G for evaluation. The 30.23 prototype was formally accepted by the LFT in October 1918 and remained at Aspern until the war's end.

Aviatik 30.23 Specifications
Engine: 300 hp Daimler & 2 x 230 hp Hiero
Wing: Span Upper 17.10 m (56.10 ft)
Total Wing Area 83.6 sq m (900 sq ft)
General: Length 12.30 m (40.35 ft)
Empty Weight 2681.6 kg (5913 lb)
Loaded Weight 3784.1 kg (8344 Ibj
Maximum Speed: 110 km/hr (68 mph)
Climb: 1000m (3,281 ft) in 5 min 29 sec
2000m (6,562 ft) in 13 min 10 sec
3700m (12,139 ft) in 45 min


Aviatik 30.34

  Aviatik began construction of two bomber prototypes, 30.23 and 30.34, in February 1917. The fuselage of 30.34 was ready for the plywood covering in June when work was halted to give priority to 30.23 completion. In December 1917, Aviatik proposed replacing the center engine by a forward gun turret, mounting the outer engines as tractors, and dividing the undercarriage to allow bomb rack installation under the fuselage. Calculations submitted by Aviatik showed that the bomber would have greater reliability due to reduced engine and fuel weight. Flars rejected the proposal but approved the installation of three 230 hp Hiero engines and urged that work start at once. The 30.34 was reported "almost complete" on 15 March 1918. In a letter dated 24 August 1918, Aviatik complained to Flars that the program had been neglected, nor had the Hiero engines been delivered - this at a time when the LFT command urged the development of the Aviatik G.III prototypes "by all possible means." Even so, at war's end the 30.34 was only 80 percent finished.


Aviatik G.III Series 131

  On 15 March 1918, two days after the maiden flight of the three-engined 30.23 prototype, Flars confirmed an order for four pre-production bombers, designated Aviatik G.III series 131, intended for weapons trials and service evaluation. The contract was signed on 29 May 1918. Loosely based on the 30.23 and 30.34 layout, the series 131 was designed around three 230 hp Hiero engines and fitted with a split undercarriage. On 23 July 1918, Berg submitted project specifications for three versions:
  Version 1: a day bomber carrying three crew members, armed with three machine guns and capable of lifting a 400 kg (882 lb) bomb load.
  Version 2: a night bomber with a two-man crew, armed with two machine guns and a bomb capacity of 1000 kg (2205 lb).
  Version 3: a ground-attack machine armed with three guns, carrying extra ammunition but no bombs, and 300 kg (662 lb) of armor plate to protect the three-man crew.
  To improve lift, Flars proposed a 50 percent wing-area increase over the 30.23. Uzelac suggested fitting the 30.23 with a nose turret to increase firepower and using the center engine to drive a supercharger to attain higher altitude. These suggestions were rejected, although in August 1918 Flars approved plans to fit two G.III bombers with a nose turret in place of the third engine. Details of the final design are unknown, but the configuration of the production bomber was contingent on the flight test results of the two prototypes at the time under development. Flars urged work on the G.III to proceed "with all possible speed" and placed a production order for an additional 25 bombers. Provided the operational trials were successful, the production would be increased to 50 machines at the expense of Fokker D.VII(Av) output. As projected in August 1918, Aviatik was slated to deliver the first of 29 G.III bombers in October 1918 and continue at the rate of three bombers per month through August 1919. As reported on 31 October 1918 when assembly work was halted, two G.III airframes were 20 percent and two 15 percent complete.
  The Aviatik G.I and G.II have not been identified in LFT records. It is believed that these designations may have been reserved for the 30.23 and 30.34 prototype bombers after being removed from prototype status arid sent to the Front for evaluation.

Aviatik G.III Series 131 Day Bomber Specifications
Engine: 3 x 230 hp Hiero
Wing: Total Wing Area 126 sqm (1356 sq ft)
General: Empty Weight 2500 kg (5513 lb)
Loaded Weight est. 3865 kg (8522 lb) est.

Aviatik G.III Series 131 Night Bomber Specifications
Engine: 3 x 230 hp Hiero
Wing: Total Wing Area 126 sq m (1356 sq ft)
General: Empty Weight 2500 kg (5513 lb) est.
Loaded Weight 4425 kg (9757 lb) est.

Aviatik G.III Series 131 Ground Attack Specifications
Engine: 3 x 230 hp Hiero
Wing: Total Wing Area 126 sq m (1356 sq ft)
General: Empty Weight 2500 kg (5513 lb| est.
Loaded Weight 3610 kg (7960 lb) est.

Aviatik 30.03

  The 30.03 biplane was the first aircraft assembled by the Aviatik company in Vienna with help of skilled workmen loaned by the German Aviatik company. Identified on existing manufacturer's drawings as the prototype for the B.II series 32 biplane, the 30.03, powered by a 100 hp Daimler engine, was accepted in September 1914. In mid-1915, the 30.03 was tested with both 150 hp and 160 hp Daimler engines with a box radiator installed over the engine in preparation for producing the “improved B.II" series 34. The 30.03 was later attached to Flek 3 as a trainer and was officially written-off in May 1918.


Aviatik B.II Series 32 and 32.7

  On 22 July 1914, the newly-organized Aviatik company received an LA order for 33 (later reduced to 23) biplanes based on the original P 14 design and powered by a 120 hp Daimler engine. These aircraft were designated oAv-1 to oAv-23. Since delivery was of the utmost urgency, the LA command recognized that components or even airframes for the initial 10 aircraft must come from Germany. With the help of skilled workmen on loan from the German company, the first four Austrian-built biplanes (including the 30.03 prototype) were completed and accepted in September 1914. On 4 March 1915, an additional 21 biplanes were ordered followed by four on 15 September 1915, giving a total of 48, the last of which was accepted in December 1915. In February 1915, the aircraft were re-designated Aviatik B.II series 32 and numbered 32.01 to 32.48.
  Initially, pilots reported unpleasant flight characteristics. At full throttle and in a climb the B.II pulled strongly left, and in a glide pulled to the right. Flying in gusty weather was very tiring. Because of the small controls, the aircraft had a tendency to veer off course which required the pilot's constant attention. This was ameliorated by increasing the aileron and rudder surfaces and changing the wing adjustment. The B.II was underpowered; consequently in August 1915 a 150 hp Daimler engine was installed in some aircraft. From September 1914 until withdrawal in September 1915, the B.II was used for unarmed reconnaissance by Fliks 3, 11, 13 and 14 on the Eastern Front where operating altitude was not a factor. Even here, Flik 14 reported that one B.II required one and a half hours to reach 1000 meters (3281 ft)! In the mountainous terrain of the Karnten Front, Flik 16, having received seven B.II biplanes in early June 1915, found that none could climb above 2900 meters (9515 ft) - not nearly high enough to evade ground fire from Italian troops holding positions at 2800 meters (9187 ft). In fact, Flik 16 did not operate over Italian lines until the arrival of the Lloyd C.II in September 1915. At the end of 1915, the B.II series 32 biplanes were withdrawn from the Front and assigned to Fleks 2-6, 8, and 9 as basic trainers. Nine were still active in July 1917. Those which were not modified for dual control retained the original serial number.
  In late 1915, Flars ordered 12 Aviatik B.II dual-control trainers numbered 32.51 to 32.62 and fitted with reconditioned 120 hp Daimler engines. The contract was signed on 5 February 1916, at which time delivery was already under way. It is probable that these were re-built aircraft for they do not appear in the Flars new aircraft acceptance lists. A total of 26 B.II biplanes were re-built as dual-control trainers. In May 1916, the designation B.II series 32.71 to 32.96 was established to set them apart from the standard B.II series 32 biplanes. The dual-control trainers were re-designated as follows:
Conversion Number Original Number Conversion Number Original Number
32.71 32.01 32.84 32.52
32.72 32.04 32.85 32.53
32.73 32.08 32.86 32.54
32.74 32.15 32.87 32.55
32.75 32.16 32.88 32.56
32.76 32.17 32.89 32.57
32.77 32.26 32.90 32.29
32.78 32.28 32.91 32.45
32.79 32.34 32.92 32.58
32.80 32.41 32.93 32.24
32.81 32.42 32.94 32.59
32.82 32.43 32.95 32.33
32.83 32.51 32.96 32.39
  Until the advent of the Aviatik trainers, Austro-Hungarian aircrews received their instruction on single-control aircraft. Dual-control lessons began on 15 March 1916 at Flek 4, followed in short order by Fleks 2 and 3. In July 1917, the remaining 15 B.II series 32.7 trainers were scheduled for replacement by the Brandenburg B.I(Fd), but five or six were still flying in mid-1918.

Aviatik B.II Series 32 Specifications
Engine: 120 hp Daimler
Wing: Span Upper 14.00 m (45.93 ft)
Span Lower 10.54 m (34.58 ft)
Chord Upper 1.88 m (6.17 ft)
Chord Lower 1.88 m (6.17ft)
Sweepback Upper 4.5 deg
Sweepback Lower 4.5 deg
Gap 1.91 m (6.27 ft)
Stagger 0 m (0 ft)
Total Wing Area 45 sq m (484 sq ft)
General: Length 8.63 m (28.31 ft)
Height 3.15 m (10.33 ft)
Track 2.05 m (6.73 ft)
Empty Weight 825 kg (1819 lb)
Loaded Weight 1250 kg (2756 lb)
Maximum Speed: 110 km/hr (68 mph)
Climb: 1000m (3,281 ft) in 10 min 20 sec


Aviatik B.II Series 34

  Because the B.III was not ready for production, Flars directed Aviatik to continue building the B.II to avoid interrupting output. Flight trials of the "improved B.II" were performed with the 30.03 prototype. Assembly was already in progress, when in September 1915 contracts were signed for 24 B.II series 34 biplanes, followed on 30 November 1915 by a second batch of 25. These were numbered 34.01 to 34.49. The occurrence of the serial number 34.00 in Flars records leads to the assumption that this may have been a production prototype or possibly aircraft 30.03. The B.II series 34 was fitted with a 150 hp Daimler engine and a box radiator mounted over the engine. In most other respects, the airframe was identical to the B.II series 32. Acceptances began in September 1915 and ended in April 1916.
  Beginning September 1915, the B.II series 34 was supplied to Flik 16 in Karnten; Fliks 2, 4, 8, and 12 on the Isonzo Front; and Fliks 1, 3, 5, 11, 13, 14, 18, 20, 22, 26, and 27 on the Eastern Front. Being higher powered, the B.II series 34 was well-received and provided reliable service as a general-purpose machine. Some machines were equipped with a wireless transmitter for artillery spotting. Infrequent bombing attacks were flown by aircraft carrying three 20kg (44 lb) bombs, dropped by the observer through a trap-door in the fuselage.
  The B.II series 34 was gradually retired from service beginning in mid-1916 and, as customary, transferred to training units. Beginning in January 1917, as they came to Aviatik for repair, 43 B.II series 34 were fitted with dual controls. Twenty-three trainers were in service on 31 August 1917, and a handful were still flying in late 1918.

Aviatik B.II Series 34 Specifications
Engine: 150 hp Daimler
Wing: Span Upper 14.00 m (45.93 ft)
Span Lower 10.58 m (34.71 ft)
Chord Upper 1.88 m (6.17ft)
Chord Lower 1.88 m (6.17 ft)
Sweepback Upper 4.5 deg
Sweepback Lower 4.5 deg
Gap 1.91 m (6.27 ft)
Stagger 0 m (0 ft)
Total Wing Area 45 sq m (484 sq ft)
General: Length 8.63 m (28.31 ft)
Height 3.15 m (10.33 ft)
Track 2.05 m (6.73 ft)
Empty Weight 830 kg (1830 lb)
Loaded Weight 1220 kg (2690 Ib)
Maximum Speed: 123 km/hr (76 mph)
Climb: 1000m (3,281 ft) in 8 min 30 sec

Aviatik B.III Series 33

  The Aviatik B.III was designed in early 1915 by Karl Illner and Ingenieur Alfred Gassner, completely independent of help from the parent company in Germany. It did not prove successful at the Front. The production contract, signed on 9 April 1915, called for 25 aircraft with delivery to be completed in June 1915. Because of protracted engineering delays, the contract was cancelled and assigned to the Aviatik B.II series 34, a type then in production. The B.III was finally approved on 6 September 1915 when Flars ordered 28 aircraft powered by a 160 hp Daimler engine. An additional 24 aircraft were ordered on 20 April 1916. Delivery of the 52 B.III biplanes, numbered 33.01 to 33.52, was scheduled to be completed in May 1916.
  However, even after months of design effort, Aviatik proved incapable of demonstrating an acceptable production prototype. Flars directed Mises to provide assistance. In December 1915, an "experimental series 33 aircraft" using the Aviatik 30.01 airframe fitted with a Mises-designed wing was flight tested. When flown under ideal conditions, the B.III prototype was reported as being superior to the Aviatik B.II series 34. Nevertheless, Aviatik was penalized by Flars because the B.III production aircraft had failed to reach contractual performance specifications.
  Beginning February 1916, the B.III was assigned to Fliks 5, 10, 14, 20, 22 and 27 on the Eastern Front. Overweight and underpowered, the B.III proved to be sluggish, and in gusty weather the aircraft's pendulum behavior earned it the sobriquet of "rocking chair" by flight crews who regarded the type as "deplorable." The B.III did not last long at the Front, and in the summer of 1916 it was withdrawn and assigned to training service.
  The large cockpit that enabled the instructor to easily reach the flight controls, the gentle qualities and slow speed made the B.III an acceptable trainer. In fact, only one aircraft, 33.27, was fitted with dual controls. A total of 37 were assigned to Fleks 3, 4, 14, and 15 in July 1917. The B.III continued to train pilots through 1918 in decreasing numbers.

Aviatik B.III Series 33 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 15.30 m (50.20 ft)
Span Lower 11.27 m (36.97 ft)
Chord Upper 2.10 m (6.89 ft)
Chord Lower 2.10 m (6.89 ft)
Sweepback Upper 6 deg
Gap 2.00 m (6.56 ft)
Total Wing Area 42.2 sq m (454 sq ft)
General: Length 9.40 m (30.84 ft)
Height 3.47 m (11.38 ft)
Track 2.20 m (7.22 ft)
Empty Weight 920 kg (2029 lb)
Loaded Weight 1357 kg (2992 lb)
Maximum Speed: 122 km/hr (76 mph)
Climb: 1000m (3,281 ft) in 8 min 5 sec

Aviatik 30.07

  Work on the experimental 30.07 bomber, the largest aircraft built in Austria-Hungary, began on 5 November 1915 when Flars established a design team of Flars engineers jointly directed by Oberleutnant Professor Richard von Mises and Ingenieurleutnant Karl Saliger. By January 1916 the airframe configuration had been agreed upon. The wing profile was tested in Knoller's wind tunnel at the Polytechnic Institute, where Professor Richard Katzmayr analyzed propeller and propulsion design. In his writings, Mises conveys the excitement and manifold difficulties encountered in bringing such a complex project to completion.
  On 24 November 1915, Aviatik received a Regiebau contract (a government-managed, cost-plus-fixed-fee agreement) for which the company provided space and labor but assumed no engineering responsibility. Component manufacture began at Esslingen in December 1915, causing the Flars resident inspector to complain that regular production work was being neglected. Airframe assembly of the Mises bomber, now numbered 30.07 (project designation Gr.I), was under way in January 1916.
  The 30.07 bomber was constructed around two internal transmission units, powered by the experimental 300 hp Daimler V-12 engine. Each was fitted with a double-ended crankshaft that drove, via two gearboxes and outrigger shafts, a pair of counter-rotating, tractor airscrews mounted athwart the fuselage. The power units, installed sideways in the fuselage, were separated by the pilot's cockpit. The outriggers were mounted independently of the wing structure, a desirable feature in case of transmission shaft failure. The power units were manufactured by Daimler and serviced by MAG engineers.
  The transmission was bench-tested in mid-March 1916, followed by full airframe thrust measurements on 19 May. When the bomber appeared for taxi trials on 1 June, the undercarriage collapsed, requiring a stronger shock cord assembly. One totally unexpected problem was the "hours of frustrating toil" required to start the engines. The new engines were prone to sparkplug oiling, and worse, since an auxiliary starting mechanism was not provided, it was physically awkward and exhausting to swing the propellers. An extended taxi run was performed on 27 June. Finally, after careful engine servicing on July 1, test pilot Ingenieur Franz Sattler performed taxi runs and several short hops to satisfy himself that the aircraft was controllable in flight. On 2 July 1916, with Mises in the co-pilot's seat, 30.07 made its maiden flight around the Aspern airdrome lasting ten minutes. Two days later on its second flight, 30.07 reached 350 meters (1148 ft) but during landing, the bomber lost speed and stalled-in from four meters (13 ft). The damage was expected to be repaired by 20 July, allowing time for minor structural changes and engine removal for overhaul.
  The 30.07 was destroyed on 28 July 1916. In an official report, Mises stated that the 30.07 hung sharply to the right at takeoff. Sattler reacted by pulling up too quickly and crashed from 20 meters (66 ft) onto the right wing. "Kindling wood", remarked Mises who, like Sattler, was spared injury thanks to the strongly-built pilot's enclosure. In spite of the short time aloft, flight evaluation was generally positive; the prototype flew smoothly with great stability and, except for the sluggish aileron response, was relatively easy to control. Most of the improvements concerned the engines. Mises recommended better cooling, new carburetors, and auxiliary engine starters. The bomber was grossly overweight owing to the unexpectedly high drive-system weight, which in turn reduced the useful load by 1000 kg (2205 lb). Some 300 kg (662 lb) would have to be removed to make the design viable. The Mises bomber remained a priority program and construction of the improved 30.17 and 30.18 bombers was already under way.

Aviatik 30.07 Specifications
Engine: 2 x 300 hp Daimler
Wing: Span Upper 22.60 m (74.15 ft)
Chord Upper 3.00 m (9.84 ft)
Chord Lower 3.00 m (9.84 ft)
Sweepback Upper 4 deg
Gap 3.06 m (10.04 ft)
Total Wing Area 118 sq m (1270 sq ft)
General: Length 15.37 m (50.43 ft)
Height 4.45 m (14.60 ft)
Track 3.60 m (11.81 ft)
Empty Weight 2800 kg (6174 lb)
Loaded Weight 4500 kg (9926 lb)
Maximum Speed: 135 km/hr (84 mph)


Aviatik 30.17 and 30.18

  Concurrent with the assembly of the Aviatik 30.07 (Gr.I) prototype, preliminary design work continued on two prototypes, 30.17 (designation Gr.II) and 30.18 (Gr.III), that would incorporate improvements based on the limited experience gained with the 30.07. The guidelines, laid down on 3 August 1916, recommended raising the engines to place the exhaust system in the slipstream and installing a modified transmission system. The fuselage was shortened and fitted with a ventral gun position. The undercarriage was redesigned with lighter wheels and steel springs replaced the rubber shock cords. Components salvaged from the 30.07 crash were used in the 30.17 airframe. As projected, the 30.17 and 30.18 bombers were powered by two 345 hp Daimler V-12 engines, manned by a crew of four and capable of carrying a 350-500 kg (772-1102 lb) bomb load.
  At the time the contract for two bombers was signed on 5 October 1916, the assembly of the 30.17 was nearing completion at Esslingen. It arrived at Aspern in late October 1916. By then the bomber program had lost much of its impetus. Mises was unable to devote full time to his project for he had been promoted to supervise the Flars engineering department. Mises hinted at personality clashes within Flars but did not elaborate. As Flars' "technical fireman", he travelled extensively to correct problems and in October 1916, Mises was ordered to Flek 11 in Mostar to gain flying experience with operational aircraft. In his absence, the Mises bomber program came to a halt. Faced by the escalating air war on the Italian Front, the LFT could hardly justify diverting manpower and scarce materials for a project that promised no immediate benefit. In fact, little flying was undertaken with the 30.17 during the winter months. To make production space available at Esslingen, on 10 May 1917 the 30.17 was transferred to Flek 6 in Wiener-Neustadt where sufficient tests were performed to enable Oberleutnant Antal Lanyi-Lanczendorfer to submit a fairly comprehensive flight report (23 November 1917):
  1) the aircraft begins to roll with engines turning at 900 rpm.
  2) suspension and tail skid are very good; tires are unsatisfactory.
  3) the aircraft can take off and fly on one engine.
  4) the aircraft maneuvers freely. When a gust caused the left wing to drop, it was righted easily using the ailerons.
  5) rudders are well balanced and elevator controls are more sensitive than those of the Brandenburg G.I.
  6) all controls can be manipulated without using excessive force.
  7) aircraft lands easily, undercarriage strength appears adequate.
  8) faults: the engines oil-up rapidly and are difficult to stop.
  After the engines had been removed and modified by Daimler, the 30.17 was ordered to Strasshof on 28 January 1918 to install service equipment in preparation for frontline evaluation with Flik 102/G. But at Wiener-Neustadt on 19 March, the 30.17 was damaged beyond repair during a landing approach. It appears that a low-altitude stall, such as destroyed the 30.07, was the cause. Fortunately, the robust cockpit structure prevented injury to the flight crew.
  The last Mises bomber, 30.18, completed in December 1916, was given a lighter airframe and ailerons were fitted to the lower wings. Flight trials began at Aspern in January 1917. The 30.18 was slightly damaged on 25 May 1917 because the new 345 hp Daimler engines failed to produce full power. From June to September 1917, cursory flight tests were performed at Flek 6 using the more reliable 300 hp Daimler engines. The 30.18, again fitted with 345 hp engines, was damaged on 1 April 1918 during the course of flight and speed trials. The bomber was reported in good condition at Aspern on 25 October 1918.

Aviatik 30.17 Specifications
Engine: 2 x 345 hp Daimler V-12
Wing: Span Upper ca 22.60 m (74.15 ft)
Chord Upper 3.00 m (9.84 ft)
Chord Lower 3.00 m (9.84 ft)
Gap 3.06 m (10.04 ft)
Total Wing Area 118 sq m ( sq ft)
General: Length 14.45 m (47.41 ft)
Height 4.25 m (13.94 ft)
Track 3.60 m (11.81 ft)
Empty Weight 3078 kg (6787 lb)
Loaded Weight 4720 kg (10,408 lb)

Lohnerwerke GmbH, Wien-Floridsdorf

  Lohner had begun to manufacture Taube airframes for Igo Etrich whose painstaking experiments, begun in 1904, were crowned with success in April 1910 when the Taube finally achieved controllable flight. With customers waiting, but lacking funds to start manufacturing, Etrich licensed Lohner on 7 July 1910 to build five Taube monoplanes. Shortly thereafter Etrich sold the Taube patents and airfield property at Wiener-Neustadt to the Motor-Luftfahrzeug-Gesellschaft (MLG), an aeronautical trading firm (balloons, airships and aircraft) managed by the Viennese financier Camillo Castiglioni. Lohner continued to build the Taube airframes which were transported to Wiener-Neustadt where engine, fuel system and instruments were installed under the supervision of Karl Illner, formerly Etrich's test pilot and shop manager. Of the 58 Etrich Taubes built by Lohner, 10 were exported to Italy, Russia, Spain, England, China and Germany, 29 were delivered to the Austro-Hungarian air service between 1911 and 1913, and the remainder were sold privately or retained by the MLG flight school. Attempts to modernize the Taube design in 1913 by streamlining and increasing power were unproductive. The Taube had reached the end of its development cycle, a fact recognized far earlier in Austro-Hungarian military circles than in German ones.


Lohner 10.08 to 10.11

  Soon after mobilization, the Lohner-MLG flying school in Wiener-Neustadt closed its doors and sold four of the school's Etrich Taube trainers to the LA on 24 August 1914. These were assigned the numbers 10.08 to 10.11 in February-March 1915.
  The Lohner 10.08 trainer, powered by a 65 hp Daimler engine, evidently remained in service for several years, since it was not officially written-off until 10 January 1918.
  The Lohner 10.09 trainer, powered by a 65 hp Daimler engine, initially carried the designation F-01. As 10.09, it served with Flek 1 from 1914 and was last reported active in December 1915.
  The Lohner 10.10 trainer, powered by a 80 hp CAM (Clerget) in-line engine, was flown by Flek 1 in 1914. After being damaged and extensively rebuilt by Fischamend, it was designated F-3 (later 72.03). It should be noted that this "new" F-3 (ex 10.10) was a replacement for a written-off Fischamend-built Taube also numbered F-3. The reason for the confusing re-assignment of numbers is not known.
  The Lohner 10.11 was a ground instruction Taube about which further data is lacking.


K.u.K. Fliegerarsenal Flugzeugwerk Fischamend
Fischamend

  At the time the Luftschifferabteilung (LA) was formed in 1909, funds were allocated for establishing a development and repair center to support all aspects of aeronautical technology. In 1911-1912 the center was moved from the overcrowded Vienna Arsenal to the vast Fischamend airfield (21 km west of Vienna on the Danube). The new facility consisted of 1) an observation balloon workshop, a gas-generating plant, and supply depot, 2) an experimental department to test and accept military aircraft, 3) an aircraft and engine repair shop, and 4) an airship department. The military command soon realized that the vast expense of building and maintaining an airship fleet would rapidly deplete the limited aviation budget; consequently the LA gradually abandoned airship activity in favor of more cost-effective aeroplanes.
  When the Fliegerarsenal (Flars) was established in March 1915, the Fischamend aviation center came under its command. Fischamend was responsible for a wide range of aeronautical work encompassing instrumentation, bombs, wireless, photography, radiators, helicopters and airborne weaponry. However, the primary flight test and aircraft acceptance center remained at Aspern. Professor Richard Knoller, aided by von Karman, Julius Kolin, and Wilhelm Zurovec, designed and built a full-scale propeller wind tunnel and testing laboratory, acknowledged as the most advanced of its time. The propeller test laboratory was completed in early 1917.
  In 1912-1913, the aircraft repair shop (later named Flugzeugwerk = aircraft works) began to manufacture aircraft because the Motor-Luftfahrzeug-Gesellschaft (MLG) and Lohner had difficulty meeting delivery schedules. The 14 Lohner-built Etrich Type F Taubes, ordered in May 1912, proved severely nose-heavy and had to be rebuilt by Lohner. The unstable Etrich-Lohner Type X Taube with side-by-side seating for training use (four ordered in April 1912) required modification and were not delivered until 1913. Fearing that the overburdened Lohner factory would encounter delays in producing the 28 Type B Pfeilfliegers and precipitate an "aircraft shortage," the LA secretly manufactured ten Etrich Taubes in the Flugzeugwerk without seeking permission of Etrich or MLG, the rightful patent owners. When MLG got wind of this in late 1913, the LA confessed to patent infringement but countered by invoking a contractual fine for late aircraft delivery. Although the controversy was eventually settled, the relationship between the LA and MLG-Lohner became severely strained. MLG was accused of being no more than a trading organization (which it was) having "little incentive to foster the development of the Etrich Taube" - a fair criticism. Throughout the war Castiglioni, the business director of MLG, remained an anathema to the LA command.


Etrich 70.01 to 70.06

  With the implementation of the unified numbering system on 8 February 1915, the oldest pre-war Etrich Taube trainers were assigned the series 70 designation, reserved for "out-of series" and prototype aircraft:
Original Designation Second Designation Final Designation
Condor 70.01 72.35 after repair in April 1915
Falke 70.02 72.37 after repair in April 1915
S.III 70.03 written-off
X-IV 70.04 written-off November 1915
S.V 70.05 72.38 after repair in May 1915
X-III 70.06 72.33 after repair
  The first two came from a batch of Maneuver Etrich 1911 (Etrich Type B) named Adler (eagle), Buzzard, Condor, Dohle (jackdaw), Elster (magpie), Falke (falcon) and Geier (vulture), ordered from Lohner on 10 May 1911.
  In 1913, Fischamend delivered eight School Etrich, designated S.I to S.VIII. Records show that on 1 February 1914 five School Etrich, numbered S.I to S.V, were stationed at various Flugparks for training purposes.
  Four Etrich Type X trainers were ordered from Lohner on 19 April 1912, but not delivered until March 1913 owing to severe stability problems which required rebuilding the airframe.
  As shown above, in the course of repair at least four series 70 Taubes were later rebuilt as a standard Etrich A.II(Fd) series 72 trainer.

Etrich Taube (Fd) 70.01
Engine: 90 hp Daimler
Wing: Span 14.00 m (45.93 ft)
Total Wing Area 32.5 sq m (350 sq ft)
General: Length 10.00 m (32.81 ft)
Height 3.50 m (11.48 ft)
Empty Weight 480 kg (1058 lb)
Loaded Weight 750 kg (1654 lb)
Maximum Speed: 105 km/hr (65 mph)
Climb: 1000m (3,281 ft) in 20 min


Etrich A.I(Fd) Series 71

  For the Grand Army Maneuvers in the summer of 1912, the LA ordered 14 Maneuver Etrich 1912 Taubes (Type F) from Lohner on 28 May 1912. Flight tests proved the Type F to be severely nose-heavy, which made it necessary to relocate the passenger from the front to a position behind the pilot, shift the fuel tank, and move the engine aft by two cylinder lengths. The aircraft were christened Aar, Achilles, Adjudant, Afra, Ajax, Allans, Amazone, Amourette, Anita, Anny, Aram, Arnim, Asra, and Atair. At a later date Albus joined the ranks.
  On 17 February 1915 those aircraft remaining in the LA inventory were designated Etrich A.I(Fd) series 71 and assigned the following series 71 numbers:
Original Designation Second Designation Final Designation
Aar 71.01 72.42 after repair July 1915
Achilles 71.02 72.32 after repair March 1915
Albus 71.03
Ajax 71.04
Anita 71.05
Aram 71.06 72.43 after repair July 1915
Arnim 71.07 72.34 after repair March 1915
Atair 71.08
Anny 71.09
Afra 71.10 72.36 after repair
  The Etrich A.I(Fd) Taubes were powered by 65 hp or 90 hp Daimler and 85 hp Hiero engines. Serving as ground or basic trainers with Fleks 3, 4, 5, and 7, six Etrich A.I(Fd) were on charge as of 6 October 1915, and at least one, 71.03, served through November 1916.


Etrich A.II(Fd) Series 72

  In addition to eight Etrich Type S Taubes, the Flugzeugwerk built approximately 30 Type F Taubes; the first ten appeared in 1912-1913 under the designation F.1 to F.10. These had been surreptitiously built without notifying the rightful patent owners (MLG and Etrich) as described in the introduction. The designations were changed in February 1915 when the extant Taubes F.1 to F.20 became Etrich A.II(Fd) 72.01 to 72.20. A total of 43 Etrich A.II|Fd) Taubes up to number 72.43 have been identified, composed of Fischamend-built Type F Taubes and other Taubes which after repair and/or modification were re-designated as shown below. In several cases after a Taube had been written-off, its number was not cancelled but re-assigned to a different aircraft.
  Redesignation of various Taubes to Etrich A.II(Fd) Series 72 was as follows:
Original Second Final Original Second Final
10.10 F.3 72.03 Condor 70.01 72.35
Buzzard F.14 72.14 Afra 71.10 73.36
S.VI F.29 72.29 Falke 70.02 72.37
S.II F.30 72.30 S.V 70.05 72.38
Achilles 71.02 72.32 F.2 72.02 72.41
X-III 70.06 72.33 Aar 71.01 72.42
Arnim 71.07 72.34 Aram 71.06 72.43
  Operated by most LFT training units, the Etrich A.II(Fd), either powered by the 85 hp Hiero engine or the 65 hp Daimler, served as a ground instructor or performed basic-training flights. Pilot Franz Zuzmann recalled that it was virtually impossible to crash a Taube. It was inherently stable and the wing-warping controls required great exertion to change aircraft direction. The instant the steering controls were centered (hands off!) the Taube would resume its normal flight attitude. Although landing accidents were common, they rarely caused severe injury. As of 6 October 1915 seventeen A.II(Fd) Taubes were listed in flying condition and 21 were under repair. Twelve were still on charge in July 1917.

Etrich A.II(Fd) Series 72
Engine: 65 hp Daimler
Wing: Span 14.60 m (47.90 ft)
Total Wing Area 31.5 sq m (339 sq ft)
General: Length 9.73 m (31.92 ft)
Height 3.28 m (10.76 ft)
Empty Weight 540 kg (1191 lb)
Loaded Weight 790 kg (1742 lb)

Knoller 30.05

  As their first aircraft, the Knoller 30.05 prototype embodied many of Knoller and Fiala's theoretical and structural ideas. The Knoller rib section, tested in his wind tunnel, had a highly-flexible trailing edge designed to flatten with increasing velocity to reduce drag. Weight and drag were minimized by a wireless wing cellule using a Warren-truss layout. Knoller's participation in the re-design of the Lohner B.I (Type B) and B.II (Type C) biplanes may have delayed the preparation of a proposal acceptable to the LA. On 11 January 1915, the LA signed a contract with Thone & Fiala to build one prototype (30.05) and five production aircraft designated Knoller B.I (Th) series 35.8.
  The 30.05 prototype, powered by a 100 hp Mercedes engine, arrived for flight testing at Aspern on 6 June 1915. Some 20 flights totalling 8 hours duration were performed under Knoller's supervision. Various modifications, including stronger struts and an auxiliary tailplane (a biplane tail was designed but not used), failed to ameliorate the dangerous flight characteristics. The 30.05 was grounded in September 1915 for being "hazardous to life." On 8 November 1915, Thone &. Fiala proposed fitting a strengthened center-section and other changes but the work was shelved to concentrate their effort on the Knoller B.I (Th) production machines.
  On 16 February 1916, the Flars acceptance group issued orders to write-off the 30.05, but the Flars command intervened and on 1 August 1916 irresponsibly lifted the flight ban. Fortunately, in view of its dangerous flight characteristics the 30.05 never was flown again. It was accepted in February 1917 and employed as an instructional airframe in a mechanics school.


Knoller B.I(Th) Series 35.8

  On 11 January 1915, the LA ordered five Knoller B.I(Th) biplanes, numbered 35.81 to 35.85 and powered by a 100 hp Mercedes engine. The first machine, 35.81, delivered on 8 October 1915, performed the maiden flight on 13 November 1915, and was flown three times by Feldwebel Franz Kuntner with an passenger aboard. "Peculiar" flight characteristics were reported, induced by excessive fuselage twisting and a noticeable deformation of the outer wing when the ailerons were actuated. New ailerons and tailplane and a reinforced center-section failed to reduce wing deformation or improve the flight traits during tests on 4 and 15 December 1915. Withdrawn for modification, the 35.81 was ready to continue trials on 8 January 1916, being joined by the new, modified 35.82 later that month. To eliminate the tail heaviness and "bizarre" control response, Knoller and Fiala had designed new ailerons, an improved rib section, an airfoil-shaped tailplane, and changed the stagger. To reduce deformation, the wings were now given wire bracing. Flight evaluation by experienced test pilots (Kuntner, Hans Mandl, Viktor Nowy, Max Perini, Johann Varga) between January and mid-April, 1916, produced a formidable list of structural deficiencies and control problems.
  Although continuing flight investigations had exposed severe shortcomings, Flars inexplicably purchased an additional batch of ten aircraft, numbered 35.86 to 35.95, on 12 February, 1916. The first five production aircraft (35.81 to 35.85), suitably modified, were delivered in March 1916. The additional weight of the airframe modifications had reduced the performance below the contractual specifications. Sporadic testing of the five aircraft continued through 24 July 1916, when the acceptance group stopped all flights, contending that the aircraft were unsuitable for frontline or training service. Nevertheless, production of the next ten aircraft (35.86 to 35.95) proceeded apace. The first two aircraft were delivered on 21 November 1916 and the last in June 1917. Records show only one of these aircraft had been flown before all were placed in storage. The 15 stored airframes were provisionally accepted in October 1917.
  The inadequacy of the Knoller-Fiala design had been amply demonstrated. Yet in the face of the aircraft's unacceptable characteristics, Knoller's lofty reputation kept the program alive and contrary to pilots' advice, the LFT stubbornly approved Knoller aircraft production at Aviatik, Lohner, Phonix and WKF beginning August 1916.


Knoller C.I(Ph) Series 25

  In spite of dangerous aerodynamic and structural problems encountered in the early Knoller biplanes, the LFT and Flats, with unwarranted optimism, awarded Phonix an order on 24 December 1915 for 48 Knoller C.I(Ph) biplanes for which 200 hp Hiero engines were specified. Production was already under way and deliveries were scheduled to end on 13 February 1916. In fact, the first production aircraft, 25.01 powered by a 160 hp Daimler engine, did not arrive at Aspern until 15 April 1916. During the flight evaluation, the 25.01 was returned to Phonix for repair at least five times, once because a fuselage frame broke while taxiing (2 August 1916). Being very lightly built, the Knoller C.I(Ph) reached a top speed of 167 km/h (104 mph) and 2000 meters (6562 ft) in 10 minutes, a very respectable performance for its day. The 25.01 was reported stable but tail-heavy and the control forces were far too heavy. Toward the end of May 1916, Uzelac flew the 25.01. His impulsive statement that “the crate is good" was unfortunately mis-interpreted as highest praise and sufficient cause to continue production. Flars rejected Knoller's plea to make further modifications on grounds that "a serviceable, high-performance aircraft should be placed into operational service as soon as possible."
  While the next two aircraft, 25.02 and 25.03, with lightened fuselages were being completed, 25.01 was reinforced, again flight tested and accepted on 25 October 1916. Faced with delays and preferring to await frontline evaluation results, Flars reduced the production order to 16 aircraft (25.01 to 25.16) - all that would be built. In November 1916, the 25.01 went to Flik 23 where it was flown by Hauptmann Heinrich Kostrba, an experienced pilot. His report was totally negative: “stability poor, nose-heavy, difficult to control in wind gusts, maximum speed only 130 km/h (81 mph), forward visibility deficient." Damaged during landing, 25.01 was returned to Phonix for repair.
  Considering that Phonix was already building the superior Brandenburg C.I, it is difficult to understand why an additional 24 Knoller
C.I(Ph) aircraft were ordered on 29 December 1916. Fortuitously, the contract was annulled. Pilots were advised to fly the type “only when absolutely necessary (ie: performing acceptance flights) and avoid sharp turns". When the reinforced C.I(Ph) 25.08 was finally load tested on 21 September 1917, the airframe failed at a load factor of 3.9, well below the proscribed factor of 5.0. In September 1917, Flars proposed using the Knoller C.I(Ph) as a trainer powered by a 160 hp Daimler engine, but the proposal was rejected. Inexplicably, rather than halting production the remaining aircraft were completed, the last being accepted in March 1918. Having served no useful purpose, 15 engineless airframes were placed in storage.

Knoller C.I(Ph) Series 25 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 12.7 m (41.67 ft)
Chord Upper 2.25 m (7.38 ft)
Chord Lower 1.76 m |5.77 ft)
Sweepback Upper 10 deg
Gap 2.10 m (6.89 ft)
Stagger 0.57 m (1.87 ft)
Total Wing Area 36.0 sq m (387 sq ft)
General: Length 8.50 m (27.89 ft)
Height 3.30 m |10.83 ft)
Track 2.23 m (7.32 ft)
Empty Weight 780 kg (1720 lb)
Loaded Weight 1217 kg (2683 lb)
Maximum Speed: 158-167 km/hr (98-104 mph)
Climb: 1000m (3,281 ft) in 4 min 45 sec
2000m (6,562 ft) in 10 min 2 sec
3000m (9,843 ft) in 17 min 5 sec


KNOLLER C.II (Lo) Series 19 and 119

  In the absence of a suitable design, Lohner, like Aviatik and WKF, was forced to accept the license-production of 48 Knoller C.II biplanes, assembly of which began in July 1916. The contract, formally signed on 8 December 1916, stipulated delivery of 48 aircraft to begin on 13 October 1916 and end on 6 January 1917. Production was to have been split evenly between 160 hp and 185 hp Daimler-engined versions, but the 185 hp engine shortage limited planned production to 16 C.II (Lo) aircraft, numbered 19.01 to 19.16. The remaining 32 machines, powered by the 160 hp Daimler engine, were to be numbered 119.01 to 119.32. In practice, the numbering scheme was changed and some unexplained numbers (ie. 19.25) have appeared in LFT records.
  Performance of the first C.II (Lo) series 19 biplanes, flight tested in November-December 1916, fell far short of expectation. Acceptance flights of the 24 completed C.II (Lo) machines was stopped in December 1916 pending correction of faults found in the Aviatik-built Knoller machines. In January 1917, aircraft 19.25, fitted with a reinforced center-section, arrived at Aspern for flight testing; however, after the wing failure of the C.II (Av) 36.07 in February 1917, Lohner designed a "normal" upper front wing spar, stronger wing fixtures and other modifications that were applied to the Aviatik and WKF-built Knoller machines as well. By mid-1917, after endless structural modifications to strengthen the airframe, the Knoller C.II aircraft were deemed safe to fly and the first Lohner production machines were accepted in May 1917.
  Flars, the driving force behind the Knoller program, was insistent that the type be evaluated at the Front. Aircraft 19.04, 19.07-19.10, a few series 119 machines, and several Aviatik-built C.IIs, were dispatched to Flik 50 and the Flieger-Versuchsabteilung Stryj (aircraft test section, later designated Flik 70) for trials in November-December 1917. Limited operational sorties were flown. The Knoller C.II was unpopular with aircrews who reported it useless as an operational machine. Flik 50 criticized the poor flight characteristics, the fragile construction, and the sloppy workmanship of the Lohner-built Knollers. The type was withdrawn from the Front.
  Most of the 185 hp engines of the C.II (Lo) series 19 were removed and the airframes placed in storage, but series 119 continued flying as an advanced trainer with Fleks 1, 5, 6, and 8. As of August 1918, four series 19 and two series 119 were carried in the frontline inventory; presumably these were used to carry mail. At the war's end, nine series 119 machines based at Flek 5 in Szeged became Hungarian property and two served with the Hungarian 5th Air Squadron. Aircraft 119.15, under repair at the Al-Ma factory in Prague, became Czechoslovakian property. After many years on exhibit in Prague, it has recently been restored.

Knoller C.II(Lo) Series 19 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 10.00 m (32.81 ft)
Span Lower 8.00 m (26.25 ft)
Chord Upper 2.08 m (6.84 ft)
Chord Lower 1.08 m (3.54 ft)
Sweepback Upper 5.5 deg
Stagger. 0.68 m (2.23 ft)
Total Wing Area 28.0 sq m (301 sq ft)
General: Length 8.50 m (27.89 ft)
Height 3.20 m (10.50 ft)
Track 2.064 m (6.77 ft)
Empty Weight 695 kg (1532 lb)
Loaded Weight 1057 kg (2331 lb)
Maximum Speed: 161 km/hr (100 mph)
Climb: 1000m (3,281 ft) in 4 min 3 sec

Knoller C.II(Lo) Series 119 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 10.00 m (32.81 ft)
Span Lower 8.00 m (26.25 ft)
Chord Upper 2.08 m (6.84 ft)
Chord Lower 1.08 m (3.54 ft)
Sweepback Upper 5.5 deg
Stagger 0.68 m (2.23 ft)
Total Wing Area 28.0 sq m (301 sq ft)
General: Length 8.50 m (27.89 ft)
Height 3.20 m (10.50 ft)
Track 2.06 m (6.77 ft)
Empty Weight 751 kg (1656 lb)
Maximum Speed: 125 km/hr (78 mph)
Climb: 1000m (3,281 ft) in 5 min 16 sec
3000m (9,843 ft) in 24 min 10 sec


Aviatik 30.08

  The 30.08 prototype, a standard Knoller B.I(Av) 35.02 airframe fitted with a 85 hp Hiero engine for evaluation purposes, was under construction in May 1916. The 30.08 prototype was ready for acceptance on 21 November 1916. In early 1917, a 100 hp Mercedes engine was fitted, returning the prototype to the standard Knoller B.I(Av) configuration. Renumbered 35.02, the aircraft was provisionally accepted and stored at the Aspern aircraft depot.


Aviatik 30.09

  In April 1916, Professor Knoller proposed a single-seat fighter conversion of the Knoller B.I(Av) powered by a 145 hp Hiero engine and armed with a gun canister on the upper wing. The aircraft was assigned the prototype designation 30.09. The maiden flight was performed by Feldwebel Ferdinand Konschel on 8 July 1916, who reported poor flight characteristics. A Flars engineering inspection on 21 August 1916 listed numerous defects, including shoddy workmanship. The 30.09 prototype, ready for acceptance on 21 November 1916, was not accepted until March 1917. In 1918 the 30.09 served as an instructional airframe at the Aspern apprentice school.


Aviatik 30.10

  Assembly of the Aviatik 30.10 biplane, prototype for the Knoller C.II(Av), began in the early summer of 1916. Although chief engineer Berg had expressed serious misgivings regarding structural integrity, the prototype was built as specified. Completed on 11 September 1916, the 30.10 was immediately grounded by Flars engineers to reinforce a fuselage frame.
  During the maiden flight on 20 September, the 30.10, powered by a 160 hp Daimler engine (not a 185 hp Daimler as specified), achieved respectable performance, reaching a top speed of 169 km/h (105 mph) and an altitude of 1000 meters (3281 ft) in 5:11 minutes. However, wing flexing and severe slipstream buffeting left the trailing-edge fabric in tatters. On 3 October the repaired 30.10 was aloft for further tests when a fuselage frame broke due to excessive elevator force and several lower wing ribs came apart. The 30.10 was grounded and, as part of the Knoller C.II(Av) program, submitted to static load tests that it failed on 31 October 1916. Aviatik director Janisch argued that the test should have been performed using a new production airframe, but Flars correctly insisted on the choice of a random airframe to prevent the company from taking special measures to assure test compliance. Further information is lacking.


Aviatik 30.11

  Existing archival records regarding the Aviatik 30.11 prototype are in conflict. One citation identifies the 30.11 as a Knoller B.I(Av) biplane modified to carry one machine gun for armament. Another document states that the prototype was similar to the Knoller C.I(Ph) but fitted with an observer's machine gun tower (Turm). Since no record of construction has been found, it is possible the 30.11 remained on the drawing board.


KNOLLER B.I(Av) Series 35

  Flars approved production of the Knoller B.I(Av) biplane at a time when the Thone &. Fiala 30.05 prototype was grounded because of structural weakness. Despite Professor Knoller's reputation and optimism, the design simply was not ready for manufacture. But powerful political pressure was involved. On 31 December 1915, Aviatik signed a contract for 32 Knoller B.I(Av) biplanes, numbered 35.01 to 35.32. They were powered by a 100 hp Mercedes engine. Delivery, scheduled to end on 5 March 1916, was not completed until two years later during which time only cursory flight testing took place.
  The Knoller B.I(Av) 35.01 was completed on 24 December 1915. Initial test reports revealed that not only did the aircraft possess abysmal flight characteristics but also displayed a catalog of structural and aerodynamic deficiencies. Other Knoller aircraft fared no better. During the maiden flight of 35.02 on 8 March 1916 both elevator horns failed. The observer's seat of 35.07 broke through the fuselage on 24 July 1916. That day, worried by recurring failures, Oberleutnant Viktor Nowy and Hauptmanns Josef Cejnek and Karl Nikitsch issued a joint statement condemning the Knoller B.I because "its use would place life in jeopardy." Thus, contrary to standing orders, the supervising acceptance officer temporarily prohibited further flights. Production was halted in August to await Knoller's improvements, but in reality the basic design was unsound and little could be done. Following an in-flight rudder arm fracture (35.10) and repeated load test failures (35.13 and 35.14), the acceptance officer reported on 31 October 1916 that the customary gust loads expected in flight had not been taken into account. Critics felt that while Knoller's theoretical calculations may have promised exceptional performance, his lack of design skill had produced a weak aircraft riddled with dangerous flight characteristics.
  All Knoller B.I aircraft were grounded on 8 November 1916 to allow Flars once again to methodically check the load calculations. The 35.01 was written-off after passing the static load tests on 6 March 1917. Four aircraft (35.03, 07, 08 and 12) were assigned to various training or test units and the remaining completed aircraft were stored at Aspern awaiting disposition. While Aviatik assembled the last aircraft, Knoller and Flars, as late as June 1917, were busy designing stronger fittings for the Knoller B.I(Av)! In August 1917 Flars, finally admitting the total failure of the Knoller program, accepted 31 B.I(Av) aircraft at 80 percent of cost value. The airframes were stripped and scrapped.

Knoller B.I(Av) Series 35 Specifications
Engine: 100 hp Mercedes
Wing: Span Upper 10.90 m |35.76 ft)
Span Lower 8.16 m (26.77 ft)
Chord Upper 1.65 m (5.41 ft)
Chord Lower 1.65 m (5.41 ft)
Dihedral Lower 3 deg
Sweepback Upper 5.5 deg
Gap 1.80 m (5.91 ft)
Stagger 0.85 m (2.79 ft)
Total Wing Area 29.86 sq m (321 sq ft)
General: Length 7.67 m (25.16 ft)
Height 3.01m (9.88 ft)
Track 2.05 m (6.73 ft)
Empty Weight 628 kg (1385 lb)
Loaded Weight 937 kg (2066 lb)
Maximum Speed: 132 km/hr (82 mph)
Climb: 1000m (3,281 ft) in 8 min 10 sec


KNOLLER C.Il(Av) Series 36 and 136

  Following the crash of the Aviatik 30.06 prototype, Flars switched the proposed contract for 48 machines to the Knoller C.II biplane. That this type went into production when the Knoller program was in deep trouble and largely discredited supports Graf Adalbert Sternberg's (a member of parliament) accusation of political influence wielded by Knoller's supporters. Two contracts were signed by Aviatik; one on 4 August 1916 for 24 Knoller C.II(Av) series 36 aircraft powered by a 185 hp Daimler engine, and the other on 23 September for 24 C.II(Av) series 136 powered by a 160 hp Daimler engine. The aircraft were numbered 36.01 to 36.24 and 136.01 to 136.24 respectively.
  In June 1916, with assembly already under way, Aviatik reported delays because manufacturing drawings were incomplete because of the many changes required by Knoller. The first production aircraft, 36.01, performed its maiden flight on 10 September 1916. Both the 30.10 prototype and 36.01 were temporarily grounded on 13 September 1916 for modification. Responsibilities were so ill-defined that director Janisch refused to work on the 36.01, and conversely Knoller rejected improvements suggested by Aviatik. To rectify "extreme" tail-heaviness, not alleviated by relocating the observer and internal equipment, Knoller devised an S-shaped airfoil for the tailplane. Aviatik regarded the additional lift forces imposed on the tail and fuselage as dangerous. In a climb, the aircraft remained tail-heavy and in level flight nose-heaviness increased with speed. The glide characteristics were considered good but the landing speed was unacceptably high. Throughout the flight test program, Knoller's ultra-light construction resulted in a long list of structural failures, among them: weak tail skid and control surfaces (26 October), rudder failure (8 November), static load test failure (36.08 - 21 November and 28 December), wing rib fracture (36.02 - 14 December), undercarriage collapse (36.02 and 36.04 - reported 12 January 1917).
  While the C.II aircraft were grounded, a much-modified 36.13, fitted with strut joints machined from solid steel, finally passed the static load tests on 9 January 1917. Flars permitted flight testing to continue on 17 January "but only if absolutely necessary." Steep turns were to be avoided until new strut joints were installed throughout. Despite growing aversion to Knoller aircraft, test flights continued. Flying 36.07, two aircrew were killed on 10 February 1917 when a lower wing came off. Once again the C.II was grounded. The flight restriction was lifted on 4 April, but Aviatik, under pressure to produce its own designs, had lost interest in the C.II and stopped work. Out of a total of 18 or 19 completed, only 8 C.II(Av) series 36 aircraft were accepted. None of the series 136 aircraft were completed. Forty C.II airframes were in storage at Aviatik when the war ended.
  Although Uzelac vetoed the idea, a special unit, known as the Flieger-Versuchsabteilung (experimental flying section) later to become Flik 70, was established to evaluate the C.II under service conditions. Aircraft 36.08, 36.10, 36.11, 36.14, and 36.20 formed part of the Knoller C.II contingent that went to the Eastern Front in July 1917. The Knoller C.II had such a poor reputation that few pilots cared or dared to fly it. The 18 January 1918 report shows that the years of effort were hardly worthwhile:
  The C.II can be flown only by skilled pilots, especially while landing. It tosses and swings in gusty weather but reacts rapidly and positively to the controls. In turns, altitude loss is rapid if airspeed is not carefully maintained. The observer is buffetted by a frightening propeller wash, to such a degree that he must hold on and take care not to fall out while operating the machine gun. In cold weather, impossible for the observer. Pleasant to fly in calm conditions. Good view forward.
  In August 1918, only one C.II series 36 was listed in the frontline squadron inventory against four C.II series 19, two series 119, and five series 81. A few series 36 aircraft became advanced trainers at Flek 5 or found use as instructional airframes in mechanic training schools.

Knoller C.II(Av) Series 36 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 10.37 m (34.02 ft)
Span Lower 8.14 m (26.71 ft)
Chord Upper 2.09 m (6.86 ft)
Chord Lower 1.68 m (5.51 ft)
Sweepback Upper 5.5 deg
Stagger 0.59 m (1.94 ft)
Total Wing Area 30 sq m (323 sq ft)
General: Length 8.54 m (28.02 ft)
Height 3.02 m (9.91 ft)
Track 2.06 m (6.76 ft)
Empty Weight 695 kg (1532 lb)
Loaded Weight 975 kg (2150 lb)
Maximum Speed: 160 km/hr (99 mph)
Climb: 1000m (3,281 ft) in 4 min 24 sec


Knoller C.II(WKF) Series 81

  Faced by the failure of the Lloyd C.IV and lacking an inhouse replacement, Flars filled the production gap by assigning WKF the Knoller C.II, a design of great but never-realized expectations. To the extent that drawings were available, WKF began parts manufacture for 24 Knoller C.II(WKF) biplanes, numbered 81.01 to 81.24, in July 1916. By the time the contract was officially signed on 22 December 1916, most of the assembly work was complete. Originally the 185 hp Daimler engine was specified, but owing to the engine shortage, all aircraft were delivered with reconditioned 160 hp Daimler engines. The contract called for delivery to begin on 15 November and end on 31 December 1916. The first three aircraft were ready for acceptance in December 1916, but the flight trials of the first aircraft, 81.02, demonstrated such serious structural faults, particularly the wing attachment fixtures, that further modification was required before the aircraft were deemed airworthy.
  After the Flars inspection and critique (commissioning) on 14 January 1917, aircraft 81.02 was returned to the factory to await new drawings for re-designed parts issued in April. After a suitably modified aircraft (81.05) was re-commissioned on 21 May 1917, additional modifications were specified for all aircraft. By now Lloyd C.V output had priority at the expense of Knoller production, so it was not until December 1917, after a year's delay, that the first three Knoller C.II(WKF) biplanes were accepted.
  In spite of their obsolescence, aircraft 81.01, 81.02, and 81.05 were dispatched to Flik 66/D and 81.03 and 81.04 to Flik 67/D in January 1918, but details regarding service use are lacking. Other Knoller C.II(WKF) biplanes were sporadically flown as advanced trainers by Fleks 1, 5, 8, and 18. Aircraft 81.11 and 81.23 had a special four-hour fuel tank installed for service with the airmail flight at Aspern.

Knoller 70.01 (new) and 70.02 (new)

  Professor Richard Knoller's final contribution to the war effort was a biplane fighter featuring the Knoller flexible wing profile. Designed to flatten with increasing speed, this lowered the drag that in turn added a small increment of speed. Powered by a 230 hp Hiero engine, a top speed of 240 km/h (149 mph) was projected. On 11 January 1917, the Flugzeugwerk began the detail drawings for two prototypes, designated Knoller 70.01 and 70.02. The final drawings were not finished until June 1917, at which time the wings, fuselage structure, and metal components were nearing completion. A small scale model was satisfactorily tested in Knoller's vertical wind tunnel.
  The 70.01 prototype, in its original form fitted with wing-warping controls, was flown for the first time on 23 November 1917 by test pilot Karl Kriger. Later that month it was damaged during a ground maneuver and in the course of repair at the Flugzeugwerk, fitted with ailerons and a strengthened upper wing. Sent to Aspern in March 1918, the 70.01 prototype was tested through 20 June 1918 when it was damaged in a landing accident. Because Flugzeugwerk designers were fully engaged in the design of a 350 hp Knoller observation biplane, the task of modifying the 70.01 and completing the 70.02 prototype was assigned to the Flugzeug Reparatur und Bau Anstalt (Fruba), the aircraft repair branch of the Sigmund Jaray propeller works in Vienna. Before proceeding with flight testing, Flars, on 7 August 1918, planned to load test the 70.01 prototype to confirm the structural integrity of the uncommon wing cellule and small box spars, which were not readily verified by the customary static calculations. It is not known if these load tests were performed. The second prototype, 70.02, completed in September 1918, was to continue the flight test program. If the design proved successful, it was proposed that Fruba build a pre-production batch of ten fighters, one of which was to be sent to Adlershof for further load testing under German air service procedure. When the war ended development was stopped. Both prototypes were provisionally accepted in October 1918 so that Fruba could receive payment for work performed.

Lloyd 40.01

  On its first public appearance at the Third International Flugmeeting at Aspern, director Bier brilliantly piloted the Lloyd LS 1 biplane (competition number 20) to four world altitude records. On 27 June 1914, Bier reached an altitude of 6170 meters (20,244 ft) with one passenger and on 28 June, 5440 meters (17,849 ft) with two passengers. Bier's flying skills earned him third prize overall behind Edmund Sparmann flying for Lohner and Roland Garros for Nieuport. The record-breaking Lloyd LS 1 biplane was powered by a 145 hp Hiero engine. Praised as the best in-line engine at the Flugmeeting, it was designed by Otto Hieronimus who soon became famous for his wartime engines.
  Although identified as a Lloyd product, sufficient evidence exists to demonstrate that the LS 1 was built by DFW in Leipzig. In light of the fact that Lloyd took seven months to deliver the first production aircraft, it is unlikely that the fledgling company was capable of building and fine-tuning a record-breaking competition aircraft between the opening of the factory (8 May 1914) and the first day of the Flugmeeting (21 June 1914). The LS 1 biplane (Lloyd Stahlrumpf - steel fuselage) had the characteristic DFW welded steel-tube fuselage, whereas every Lloyd fuselage was built of wood. A similar biplane photographed at the DFW factory further supports the contention that the LS 1 was built in Leipzig.
  The Lloyd LS 1 (less engine) was purchased by the LA in September 1914. A new 145 hp Hiero engine was installed and the ventral radiator replaced by one mounted above the engine. From January to August 1915, the LS 1 was flown by Flik 6 at Igalo on the Montenegro Front. In military records the LS 1 was designated Lloyd 20M (M for meeting) before receiving the prototype designation 40.01 in February 1915. In late 1915, the LS 1 was purchased as surplus by Lloyd for display at the Budapest Military Aircraft Exhibition in 1917. Miraculously, the LS 1 survived the Great War, the post-war strife, and the battle for Budapest in 1944. Restored, it can now be seen at the Transportation Museum in Budapest.

Lloyd 40.01 Specifications
Engine: 145 hp Hiero
Wing: Span Upper 14.00 m (45.93 ft)
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Stagger 0.60 m (1.97 ft)
Total Wing Area 44 sq m (474 sq ft)
General: Length 9.00 m (29.53 ft)
Height 3.00 m (9.84 ft)
Empty Weight 700 kg (1544 lb)
Loaded Weight 1100 kg (2426 lb)
Maximum Speed: 130 km/hr (81 mph)


Lloyd 40.02

  The Lloyd Type LS 2 was built by DFW on the lines of the successful DFW MD 14 biplane but powered by a 160 hp Daimler engine. After being demonstrated in Berlin, the Lloyd LS 2 was flown by DFW pilot Max Schuler, with Friedrich Seekatz as passenger, from Berlin to Budapest, with one refueling stop, on 30 June 1914. It was to have continued to Sofia the same day in hopes of obtaining a Bulgarian production order for the new Lloyd company in Aszod, but the threat of war stifled such hopes. The LS 2 was purchased by the LA on 5 September 1914. Beginning in April 1915, it was flown by Flik 6 pilots, among them Julius Arigi, on the rugged Montenegro Front. At this time a 145 hp Hiero engine was installed. The Lloyd LS 2 (also known as the Lloyd Militar Doppeldecker Nr.2 and Ll 2S) was redesignated 40.02 in February 1915. As a result of crankshaft failure on 3 May 1915, the Lloyd Ll 2S (40.02) was forced down and sank in the Bay of Traste (Adriatic). The crew, civilian pilot Heinrich Bill and Oberleutnant Emanuel Mainx, were rescued by the Navy.

Lloyd 40.02 Specifications
Engine: 160 hp Daimler
Wing: Sweepback Upper 7 deg
Sweepback Lower 7 deg
Total Wing Area 40 sq m (431 sq ft)


Lloyd C.I Series 41

  Lloyd's first production contract, signed on 29 July 1914 - the day after Austria-Hungary declared war on Serbia - called for one prototype and 12 production aircraft based on the record-breaking DFW MD 14 design. Inexplicably, the prototype was designated Lloyd Ll 14 (the number Ll 13 was not used) and the production machines were numbered Lloyd Ll 1 to Ll 12. In early 1915, the designations were changed to Lloyd C.I 41.01 to 41.12 and 41.14 respectively. All were powered by the 145 hp Hiero engine. Unlike the DFW-built LS 1 (40.01) prototype, the Lloyd C.I (Type K.B.3.14) did not use steel-tube construction for the fuselage. Production delivery, scheduled to begin on 19 September 1914 at the rate of two aircraft per week, was greatly delayed due in part to the lack of trained workmen. The last machine was not accepted until August 1915, almost a year behind schedule.
  Because Lloyd engineer and test pilot Viktor Wittmann perished in a C.I crash (10 April 1915), the first C.I biplanes at the Front were grounded in May, possibly for modification. The fact that most production machines had plywood panels partially replacing the original fuselage fabric points to possible weakness in that direction.
  The Lloyd C.I, a safe and tractable flier, initially performed unarmed reconnaissance duties in the Balkans with Flik 6, on the Isonzo Front with Fliks 2, and 4, in Karnten with Flik 16, and the Tirol with Flik 17. At the time, the C.I was the sole Austro-Hungarian aircraft capable of flying over the mountainous terrain of Montenegro and Italy where an operational altitude of 4000 meters (13,124 ft) was mandatory. In February 1916, the remaining C.I biplanes were withdrawn from combat (except 41.14 at Flik 6 that lasted until June 1916) and modified for use as trainers. Plywood-covered replacement fuselages for eight aircraft were nearing completion in the Lloyd factory in July 1916. Flown by Fleks 3 to 6 and 8, the war-weary C.Is were somewhat unpopular with aircrews. Five trainers, some re-engined with rebuilt 150 hp Daimler engines, were still active in August-September 1917.

Lloyd C.I Series 41 Specifications
Engine: 145 hp Hiero
Wing: Span Upper 14.40 m (47.24 ft)
Span Lower 13.60 m (44.62 ft)
Chord Upper 2.00 m (6.56 ft)
Chord Lower 2.00 m (6.56 ft)
Dihedral Lower 2 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 1.95 m (6.40 ft)
Stagger 0.35 m (1.15 ft)
Total Wing Area 44 sq m (473 sq ft)
General: Length 8.90 m (29.20 ft)
Height 3.15 m (10.33 ft)
Loaded Weight 1250 kg (2756 lb)
Maximum Speed: 115 km/hr (71.5 mph)
Climb: 1000m (3,281 ft) in 6 min
3000m (9,843 ft) in 23 min

Lloyd 40.03

  According to LFT records, the Lloyd 40.03 was powered by a 160 hp Daimler engine and shipped to WKF. The 40.03 may have served as a manufacturing sample for the Lloyd C.III built by WKF under license as the C.III(WKF) series 43.5


Lloyd 40.09

  The Lloyd 40.09 biplane, powered by a 160 hp Daimler engine, was the prototype for the Lloyd C.IV series 44, the first production aircraft scheduled for the all-wood veneer wing. To obtain comparative performance figures, the 40.09 was flown with both veneer and fabric-covered wings and wings of differing shape. The initial series of flight tests, completed in July 1916, demonstrated that the fabric-winged version had slightly better speed (6 km/h - 4 mph) but a marginally lower rate of climb. A second test series with new fabric and veneer wings undertaken in mid-August 1916 yielded slightly improved performance, both versions being about equal. With the completion of flight trials, the 40.09 prototype (fitted with fabric-covered wings) was re-designated as a C.IV series 44 aircraft but the actual number has not been identified.


Lloyd 40.12

  Developed in parallel with the 40.11, the Lloyd 40.12 prototype (company Type K.B.3.16A) was under construction in August-September 1916. Listed in Flars records as a modification of the fabric-winged Lloyd C.IV series 44, the 40.12, powered by a 160 hp Daimler engine, was regarded as the definitive prototype for the veneer-winged C.IV series 44.4. Because of the excellent performance achieved by the 40.11 (Lloyd C.V), further development and scheduled production of the 40.12 (as series 44.4) was cancelled. A factory drawing dated October 1916 shows that the 40.12 prototype was re-designated C.IV 44.41 and remained the sole example of the series. The airframe, less engine, was stored at Flek 17 in September 1918.

Lloyd 40.12 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 13.28 m (43.57 ft)
Span Lower 12.68 m (41.60 ft)
Chord Upper 1.54 m (5.05 ft)
Chord Lower 1.52 m (4.99 ft)
Dihedral Lower 2 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 1.80 m (5.91 ft)
Stagger 0.35 m (1.15 ft)
Total Wing Area 30.74 sq m (331 sq ft)
General: Length 8.00 m (26.25 ft)
Height 2.95 m (9.68 ft)
Track 1.90 m (6.23 ft)
Loaded Weight 1200 kg (2646 lb)


Lloyd C.II Series 42

  On 22 July 1915, the largest contract to date was awarded to Lloyd for 62 C.II reconnaissance biplanes (Type K.B.3.15) powered by the 145 hp Hiero engine. In May 1916, an additional eight C.II biplanes were ordered to provide work for the Lloyd factory, bringing the total to 70 aircraft numbered 42.01 to 42.70. Deliveries lagged substantially behind the December 1915 completion schedule, primarily because output of the license-built Hiero (Mar) engines, first installed in aircraft 42.18, did not keep pace with C.II production. Nor was the new engine sufficiently reliable. According to Flik 17 (December 1915) "It was impossible to perform more than two or three flights without the engine acting up," an experience shared by other squadrons. Although Marta technicians, rushed to the Front, were gradually able fix the problems, engine performance tended to drop off "after only 10 to 12 hours" greatly reducing the rate of climb. Deliveries were further delayed by a severe injury to the sole Lloyd acceptance pilot in August, who was not replaced until December 1915. Records show that the majority of the C.II biplanes reached the Front between February and July 1916.
  The first C.II biplanes, accepted at Aszod in August 1915, were dispatched to Fliks 16 and 17. With time, the Lloyd C.II was in service with virtually every combat squadron stationed on the Russian Front (Fliks 9, 11, 13, 14, and 26), and Italian Front (Fliks 7, 15, 16, and 17). In late 1916, with the arrival of superior aircraft, the C.II was gradually withdrawn from the Front and placed into training service. Some were fitted with dual controls. Although not very popular as school machines, 20 C.II trainers were still flying as late as August 1918.

Lloyd C.II Series 42 Specifications
Engine: 145 hp Hiero
Wing: Span Upper 14.62 m (47.97 ft)
Span Lower 13.84 m (45.41 ft)
Chord Upper 2.00 m (6.56 ft)
Chord Lower 1.70 m (5.58 ft)
Dihedral Lower 2 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 1.85 m (6.07 ft)
Stagger 0.13 m (0.43 ft)
Total Wing Area 38.3 sq m (412 sq ft)
General: Length 8.82 m (28.94 ft)
Height 3.16 m (10.37 ft|
Track 2.05 m (6.73 ft)
Empty Weight 900 kg (1985 lb)
Loaded Weight 1329 kg (2931 lb)
Maximum Speed: 128 km/hr (80 mph)
Climb: 1000m (3,281 ft) in 6 min


Lloyd C.III Series 43

  Lloyd delivered its first C.III in August 1916, just as the last of 44 license-built C.III|WKF) series 43.5 was accepted. It was never intended for Lloyd to manufacture the C.III, but delays in perfecting the veneer wing, scheduled for the Lloyd C.IV series 44, led Flars to order 16 aircraft (eight each of C.II and C.III) on 22 May 1916 to provide factory work. The C.III, referred to as a "lightened C.II" and carrying the same model number (Type K.B.3.15), was powered by the 160 hp Daimler engine. Acceptances of the C.III biplanes, numbered 43.01 to 43.08, began in August and ended in September 1916.
  Beginning in September 1916, the Lloyd-built C.III biplanes were sent to the newly-established Fliks 32 and 33 stationed on the Rumanian Front and performed general reconnaissance assignments with full satisfaction. During 1917, the Lloyd and WKF-built C.III aircraft were distributed among various Fliks for advanced flight and proficiency training. Further details can be found under Lloyd C.III(WKF) series 43.5.

Lloyd C.III Series 43 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 14.62 m (47.97 ft)
Span Lower 13.84 m (45.41 ft)
Chord Upper 2.00 m (6.56 ft)
Chord Lower 1.70 m (5.58 ft)
Dihedral Lower 2 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 1.85 m (6.07 ft)
Stagger 0.13 m (0.43 ft)
Total Wing Area 38.3 sq m (412 sq ft)
General: Length 8.82 m (28.94 ft)
Height 3.16 m (10.37 ft)
Track 2.05 m (6.73 ft)
Loaded Weight 1310 kg (2888 lb)
Maximum Speed: 137 km/hr (85 mph)
Climb: 1000m (3,281 ft) in 8 min


Lloyd C.IV Series 44 and 44.2

  Static calculations for the veneer-winged Lloyd C.IV series 44 biplane (Type K.B.3.16) were submitted to Flars for approval in February 1916. Production was under way in April and on 1 May 1916, Flars signed a contract for 48 C.IV series 44 biplanes, powered by the 160 hp Daimler engine, to be delivered between 13 May and 30 June 1916. When Flars learned that the veneer wing was experiencing serious manufacturing delays, the production total was reduced to 20 aircraft in July. Rather than stop output entirely and hoping to salvage what remained of the program, Flars decreed that all C.IV production aircraft were to be delivered with fabric-covered wings such as had been tested on the 40.09 prototype. The first C.IV aircraft was accepted in December 1916. Because the C.IV was overweight by 210 kg (463 lb), Lloyd incurred a penalty payment.
  In LFT records a total of 21 C.IV biplanes have been identified, consisting of 13 series 44, numbered 44.01 to 44.13, and eight series 44.2, numbered 44.21 to 44.28. The additional machine is believed to have been the renumbered 40.09. No explanation has been found why production was split into two separate batches, but indications are that series 44.2 was delivered with dual controls for training purposes. Because of marginal performance, the Lloyd C.IV biplanes were sent to the Eastern Front in February 1917 to serve with Fliks 11 and 26 and later Flik 43. Several were attached to frontline squadrons on the Italian Front as advanced trainer or communication aircraft. In August 1918 all remaining aircraft were ordered to home-front training establishments.
  Of the total C.IV aircraft built by Lloyd (21) and WKF (16), six were listed on frontline squadron inventory as of 1 August 1918. Eight Lloyd-built machines were offered for sale to Czechoslovakia in 1920.

Lloyd C.IV Series 44 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 14.52 m (47.64 ft)
Span Lower 13.72 m (45.01 ft)
Chord Upper 1.55 m (5.09 ft)
Chord Lower 1.55 m (5.09 ft)
Dihedral Lower 1 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 2.00 m (6.56 ft)
Stagger 0.35 m (1.15 ft)
Total Wing Area 38 sq m (408 sq ft)
General: Length 8.79 m (28.84 ft)
Height 3.18 m (10.43 ft)
Track 2.05 m (6.73 ft)
Empty Weight 909.7 kg (2006 lb)
Loaded Weight 1334.7 kg (2943 lb)
Maximum Speed: 137 km/hr (85 mph)
Climb: 1000m (3,281 ft) in 5 min 30 sec
2000m (6,562 ft) in 13 min 40 sec
3000m (9,843 ft) in 21 min 10 sec


Lloyd C.IV Series 44.4

  Concurrent with ordering 24 Lloyd C.V biplanes on 13 December 1916, Flars ordered eight C.IV series 44.4 biplanes (Type K.B.3.16A) as back-up insurance should unforeseen problems occur with the C.V's more innovative design. The veneer-winged biplanes were numbered 44.41 to 44.48 and powered by a 160 hp Daimler engine. As soon as it became apparent that the Lloyd C.V was a superior aircraft, the production contract for the C.IV series 44.4 biplanes was cancelled. Only one Lloyd C.IV series 44.4 aircraft appeared in the LFT inventory; it was number 44.41, the re-numbered 40.12 prototype.
  
Lloyd C.IV Series 44.4 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 13.28 m (43.57 ft)
Span Lower 12.68 m (41.60 ft)
Chord Upper 1.54 m (5.05 ft)
Chord Lower 1.52 m (4.99 ft)
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 1.80 m (5.91 ft)
Stagger 0.35 m (1.15 ft)
Total Wing Area 33.16 sq m (357 sq ft)
General: Length 8.00 m (26.25 ft)
Height 2.95 m (9.68 ft)
Track 1.90 m (6.23 ft)
Empty Weight 843 kg (1859 lb)
Loaded Weight 1297 kg (2860 lb)
Maximum Speed: 135 km/hr (84 mph)
Climb: 1000m (3,281 ft) in 6 min


Lloyd C.III(WKF) Series 43.5

  For WKF's initial production contract, Flars chose a more powerful version of the popular and uncomplicated Lloyd C.II biplane. Designated Lloyd C.III(WKF), the airplane differed only in the engine installation that WKF modified for the 160 hp Daimler; all other parts were interchangeable with the Hiero-engined Lloyd C.II. After receiving a letter of intent, WKF began assembly work in mid-1915, and full-scale production was under way in December. The contract, signed on 8 February 1916, called for 24 Lloyd C.III series 43.5 biplanes to be delivered beginning in December 1915 and ending in March 1916. On 23 May 1916, twelve additional C.III biplanes were ordered, scheduled for delivery in April 1916. The contract was later amended to include an additional eight C.III biplanes as a substitute for the Lloyd C.IV(WKF) that had been delayed by development problems. Thus a total of 44 Lloyd C.III(WKF) biplanes, numbered 43.51 to 43.94, was delivered between January and August 1916.
  In February 1916, the first WKF-built C.III biplanes began to reach operational units, comprising the initial equipment of the newly-established Fliks 21 and 23 on the southern Tirol Front. When Flik 15 was transferred to this Front from the Balkans in March 1916, it also was equipped with Lloyd C.III(WKF) biplanes. The type was flown singly by Fliks 2, 4, and 12 on the Isonzo Front and Flik 16 in Karnten. On the Eastern Front, the C.III(WKF) comprised the original equipment of the newly-formed Fliks 26, 29, 30, and 31, and some "second-hand" machines were assigned to Fliks 1, 9, and 11. In October 1916, Flik 34 (Isonzo Front) was given three old C.III(WKF) machines to train novice pilots in landing on small airfields, rather than endanger the valuable Brandenburg C.I(Ph) series 27 aircraft for this purpose.
  When it arrived at the Front in early 1916, the C.III(WKF) was regarded as a serviceable, all-round reconnaissance type of average performance. Most aircraft were fitted with wireless equipment. Flik 15 reported in June 1916 that the C.III had fully met the high demands imposed by the surrounding mountainous terrain. In particular, new aircraft were repeatedly able to attain 4000 meters (13,124 ft) with full service load plus 60 kg (132 lb) bombs. However, the type was inferior to the new Brandenburg C.I that had become operational at about the same time. As a consequence, frontline units often took the new(er) Daimler engines from their C.III aircraft and installed the pirated powerplants in Brandenburg machines. That the C.III was, in effect, a "hidden supply depot" remained unknown to the high command. In the summer of 1916, the complaints of "soft" wings, vibrating struts, and degrading performance began to increase, and the C.III machines were withdrawn or dispatched to units on the Eastern Front.
  In March 1917, the C.III aircraft were removed altogether from operational service and modified into dual-control trainers. They were flown by advanced students primarily at Fleks 2 to 6 and 8. As of 1 July 1917, there were 32 C.III trainers in Flek inventory, and a handful were still flying in late 1918. Eight of these were offered for sale to the Czechoslovakian government in April 1920.


Lloyd C.IV(WKF) Series 44.5 and 44.6

  Having gained experience in building the Lloyd C.III, Flars now assigned WKF the license-production of the Lloyd C.IV biplane fitted with the new Lloyd veneer-covered wing. Component manufacture was well under way when Flars confirmed the letter of intent by signing a contract on 22 May 1916 for 24 Lloyd C.IV(WKF) biplanes. All were to be delivered by 24 June 1916. It soon became apparent that delays were inevitable owing to problems encountered in manufacturing the veneer wing. Flars considered cancelling the WKF contract, but rather than scrap completed parts, the C.IV production total was reduced to sixteen aircraft as outlined below. The remainder of the order was filled by an additional eight Lloyd C.III biplanes.
  Because of the veneer wing delays, Flars directed in July 1916 that the first eight C.IV aircraft would be delivered with fabric-covered wings (tested on the Lloyd 40.09 prototype) to keep the factory workers occupied and achieve some measure of output. These aircraft were designated Lloyd C.IV(WKF), numbered 44.51 to 44.58 and powered by a 160 hp Daimler engine. They were identical with the Lloyd C.IV series 44.
  The first machine was accepted in November 1916. In December, several series 44.5 biplanes were dispatched to Flik 7 and Flik 9 on the Russian Front and remained in operational service until February 1917, when they were replaced. Some of these aircraft were modified for dual control in October 1917 and used as training aircraft. Along with the Lloyd-built C.IV, the machines were periodically attached to frontline units such as Fliks 50, 52/D, 54/D, 58/D, 59/D, and 64/F and to rear-area units such as Flek 4 and 17. Three were offered for sale to the Czechoslovakian government in 1920.
  The second batch of eight aircraft, designated Lloyd C.IV(WKF) 44.61 to 44.68, represented a totally new design based on the Lloyd C.IV 44.41 (40.12) prototype. These machines were fitted with single-bay, veneer-covered wings and given a compact, streamlined fuselage and new tail unit. Power was supplied by a 160 hp Daimler engine. The first four aircraft were accepted after great delay in February 1917. The C.IV(WKF) series 44.6 saw limited frontline service. Flik 9 had one aircraft (44.63) in March 1917 and another was flown by Flik 54/D in November 1917. Five were listed in storage in October 1918.

Lloyd 40.04

  The Lloyd 40.04 was the first of several prototypes built to investigate the veneer wing, Bier's most notable invention. A typical veneer wing consisted of five to nine ribs per wing panel, to which were attached some 10 to 16 stringers (10 mm square) spaced at even intervals around the rib profile and running the length of the wingspan. The top and bottom stringers were joined by a 2 mm plywood web running spanwise between the ribs, forming a series of box frames that imparted great strength. The outer skin was composed of 1.2 mm veneer plywood glued and nailed to the support structure. Because the inherent strength of the veneer wing eliminated the requirement for most metal fixtures and all internal wire and tube bracing, Bier reasoned that it could be assembled by unskilled workers in less time than a conventional wing. Unlike a fabric-covered wing, the veneer wing retained the airfoil shape between the ribs and could be given a glass-like finish. But the task of reducing excess weight and developing proper assembly techniques proved extremely time-consuming. In practice, the veneer wing was not as "easy to manufacture" as had been forecast. In the field minor repairs proved troublesome, and despite a varnish-coated interior, moisture condensation caused internal plywood deterioration that could not be verified by inspection.
  Powered by a 160 hp Daimler engine, the 40.04 was basically a C.II fuselage fitted with veneer wing cellule. The inherent wing strength is demonstrated by the fact that the large-span wing of 14.5 meters (47ft 7in) was braced by a single pair of interplane struts. The Lloyd 40.04, completed about the time Bier filed for his wing patent (27 April 1916), was reported in the Lloyd shops for modification in July, and flight tests continued in August 1916. In Flars records the 40.04 belongs to the group of experimental aircraft (40.09 and 40.12) that served to test and develop the veneer wing for the Lloyd C.IV series 44 and C.V series 46 biplanes.

Lloyd 40.04 Specifications
Engine: 160 hp Daimler
Maximum Speed: 147 km/hr (91 mph)
Climb: 1000m (3,281 ft) in 5 min 10 sec
3000m (9,843 ft) in 25 min 12 sec


Lloyd 40.05

  Before the appearance of synchronized guns, designers, in their quest for an unrestricted forward field of fire, sought solutions in aircraft of bizarre shape. The ungainly Lloyd 40.05 (Type FJ - Flugzeug Jager - aircraft hunter) was no exception. The gunner standing above the engine in a raised turret had an ideal position but one wonders how the pilot, given his limited field of view from the rear cockpit, was to keep the adversary in sight or communicate with the gunner. Perhaps the gunner was provided with some form of steering control? The 160 hp Daimler-engined 40.05 prototype, under construction in January 1916, appeared for flight tests in late spring 1916. Whereas structural information is quite complete in Lloyd records, the lack of performance data leads to the assumption that the 40.05 prototype, a private-venture undertaking, performed only the most perfunctory flight tests.
  Between July and September 1916, the 40.05 was modified as a single-seat fighter. According to project drawings, it was armed with three machine guns; one in a Type II VK canister over the wing and two mounted on the lower wing outside the propeller arc. After the 40.05 fighter was demonstrated at Aspern in December 1916, Flars issued this critique: "In regard to its dimensions, the reconstructed 40.05 does not appear to be the basis for a competitive fighter. Unless good performance is achieved, further work should be stopped." In the event, development of the 40.05 fighter was discontinued and production plans for the derivative Lloyd D.I series 45 fighter shelved.

Lloyd 40.05 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 11.17 m |36.65 ft)
Span Lower 10.72 m (35.17 ft)
Chord Upper 1.45 m (4.76 ft)
Chord Lower 1.45 m (4.76 ft)
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 1.90 m (6.23 ft)
Total Wing Area 25 sq m (269 sq ft)
General: Length 6.92 m (22.70 ft)
Height 3.10 m (10.17 ft)
Loaded Weight 962 kg (2121 lb)


Lloyd D.I Series 45

  Manufacture of the Lloyd single-seat fighter, based on the 40.05 prototype, was discussed by Flars in July 1916. The design drawings were completed in September and 16 series 45 fighters, powered by the 160 hp Daimler engine, were ordered in December. Armament consisted of a single Type II VK gun canister mounted over the center-section. No mention was made of the two machine guns mounted over the lower wing as originally proposed by Lloyd. Officially the design was referred to as "series 45", but had it gone into production the designation "D.I" would have been appropriate. In February 1917, the contract was annulled to make way for the Lloyd C.V.

Lloyd 40.08

  The LFT reacted swiftly to the appearance of the three-engined Caproni bomber in August 1915 by ordering that "the construction of new and more powerful bombers be pushed by all means at hand." Lloyd, Oeffag, and Phonix each received design and construction funds for two prototypes of triplane configuration with a central pilot's nacelle and two outer fuselages. By insisting on such a complex structure, Flars had saddled the manufacturers with engineering and aerodynamic problems that required a degree of design and technical proficiency which none of the firms possessed at that time. Powered by a 12-cylinder engine mounted in a central nacelle and two smaller engines in each side fuselage, the bomber was required to remain aloft on either the center or the outer engines and carry a 200 kg (442 lb) bomb load for a duration of six hours. Two gunners stationed in a large nose turret and two rear gunners provided defensive protection.
  In January 1916, Lloyd, the first company to respond, submitted drawings and specifications for two triplane bombers, known as the Luftkreuzer I and II (Type LK I and LK II - aerial cruiser). Construction of the Lloyd 40.08 (LK I) was well under way in April 1916. To meet the first week of June deadline, overtime and Sunday work was authorized. Furthermore, Flars hoped to speed progress by keeping Oeffag and Phonix abreast of the latest technical information gained by Lloyd. The 40.08 was powered by a centrally-mounted 300 hp Daimler V-12 pusher engine and two 160 hp Daimler tractor engines in the side fuselages. The tail consisted of four rudders mounted between an upper elevator and a lower stabilizer rather haphazardly suspended beneath the outer fuselages by a light tubing framework. Twin tail skids were fitted under the two center rudders. The veneer wings were constructed in typical Lloyd fashion and finished to a high gloss.
  The bomber, completed on 20 June 1916, was rolled out for engine thrust measurement on the Aszod airfield. In a horizontal, take-off position, the 40.08 appears nose-heavy and the center of gravity seems dangerously high. In fact the 40.08 did tip on its nose during ground tests, fortunately causing little damage. To avoid a repeat occurrence, a robust tricycle undercarriage was fitted. The modification work, performed at Aspern, began in July and ended late October 1916 when Oberleutnant Antal Lanyi-Lanczendorfer was assigned the task of performing the maiden flight. There is no direct proof that the 40.08 ever took to the air, although the possibility of a few ground hops can not be discounted. An official German source stated that, with the exception of taxi trials, no flight data was obtained. On 2 November 1916, Flars, reporting "great difficulties in flight testing," planned to cut the weapons load to reduce overall weight. Sporadic development work continued. A Flars recommendation, dated December 1916, to add an "extended tail skid" was approved on 13 February 1917. Flars engineers prepared the appropriate drawings which were also sent to Phonix. A proposal, dated 30 March 1917, to rebuild the 40.08 bomber in order "to gain information to decide the future of the remaining triplane bombers" (Lloyd 40.10, Oeffag 50.04 and Phonix 20.11) was rejected; all work was terminated and the airframes placed in storage. On 17 January 1918, the stripped 40.08 airframe was ordered shipped to the Eger Fliegermaterial-Depot IV for disposal.

Lloyd 40.08 Specifications
Engine: 300 hp Daimler & 2 x 160 hp Daimler
Wing: Span Upper 23.26 m (76.31 ft)
Span Middle 22.38 m (73.42 ft)
Span Lower 16.84 m (55.25 ft)
Chord Upper 2.40 m (7.87 ft)
Chord Middle 2.20 m (7.22 ft)
Chord Lower 2.00 m (6.56 ft)
Dihedral Lower 2 deg
Sweepback 8 deg
Gap Upper 2.1 m (6.89 ft)
Gap Lower 1.75 m (5.74 ft)
Stagger 0.20 m (0.66 ft)
Total Wing Area 110 sq tn (1184 sq ft)
General: Length 9.55 m (31.33 ft)
Height 5.01 m( 16.44 ft)
Loaded Weight 4840 kg (10,672 lb)


Lloyd 40.10

  The Lloyd 40.10 triplane bomber (Type LK II), ordered at the same time as the 40.08, differed in several important respects. By locating the side fuselages below the middle wing, the center of gravity was lowered but at the expense of a reduced field of fire. The center nacelle was simplified and a nose undercarriage was fitted. The general arrangement drawings were completed in January 1916 and construction was approved in February. Assembly of the wing and fuselage, halted in July to await the outcome of the 40.08 tests, was resumed in September and suspended in October 1916 to await airframe modifications with which the Lloyd design bureau was still engaged in January 1917. The 40.10 prototype was never completed. The airframe was shipped to Aspern for storage and on 17 January 1918 sent to the Eger Fliegermaterial-Depot IV for disposal.

Lloyd 40.06

  The earliest record of LA interest in a multi-engined battleplane (Kampflugzeug) dates back to 30 March 1914, when Uzelac, recognizing the importance of airborne firing trials in France and Germany, provisionally approved the development of a twin-engined battleplane armed with two machine guns. A proposal already submitted by Lohner was returned for additional study. The first formal battleplane specifications were issued to Albatros (Phonix), Aviatik, Lloyd, Thone & Fiala, and UFAG on 18 August 1914. Specified was a speed of 125 km/h (78 mph), a combat radius of 500 km (311 miles), two 165 hp Daimler engines (accessible in flight), a crew of two pilots, and two observer-gunners and 120 kg (265 lb) of armor plate. On 9 November 1914, the proposals tendered by Aviatik, Albatros, and Lloyd were tentatively approved on a cost-plus-fixed-fee basis with construction approval contingent on design improvements as requested by Flars.
  The Lloyd battleplane was designed around two 160 hp Daimler engines mounted in the fuselage facing forward and connected to a central gearbox from which outrigger shafts drove two tractor propellers mounted between the wings. The central gearbox, designed by Bier and Melczer, consisted of a complex steel-band, variable-friction clutch to start the propellers and a claw coupling to transmit full engine power (German patent 307,750 dated 10 March 1916). The production contract was signed on 28 February 1916 and work on the Lloyd 40.06 (company designation Type KF 1 - Kampflugzeug 1) was well underway in April. The gearbox built by MAG was tested in May 1916, but recurrent mechanical failures caused Lloyd to dismantle the partially-completed airframe in October 1916 to provide factory space while development of the clutch mechanism continued.
  The Flars commander, Major Ludwig Leidl, wrote on 29 December 1916 that the "Lloyd battleplane, ordered in 1914, has little chance of being useful in the field. In light of escalating gearbox development costs, it is requested that a committee be formed to bring the project to a conclusion." The committee, consisting of Flars, Lloyd, and MAG representatives, witnessed an engine bench test on 20 January 1917, the results of which have not been recorded, but the project, now almost three years old and clearly obsolescent, inexplicably was allowed to continue. On 17 May 1917, Lloyd reported the clutch-gearbox transmission as "almost complete," provided that special alloy steel required for the "spiral clutch band could be found, hopefully in Germany." At the end of May 1917, Flars wrote that in spite of its obsolescence, continuation of the 40.06 program would make "a valuable contribution to the study of geared drive systems." But the steel band was not forthcoming and work on the 40.06 prototype bomber was terminated in June 1917.

Lloyd 40.06 Specifications
Engine: 2 x 160 hp Daimler
Wing: Span Upper 19.64 m (64.43 ft)
Span Lower 18.05 m (59.22 ft)
Chord Upper 2.50 m (8.20 ft)
Chord Lower 2.50 m (8.20 ft)
Dihedral Lower 4 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 2.50 m (8.20 ft)
Total Wing Area 72.4 sq m (779 sq ft)
General: Length 10.82 m (35.50 ft)
Height 3.60 m (11.81 ft)
Loaded Weight 2660 kg (5865 lb)


Lloyd 40.07

  By late 1915, development of the 350/400 hp Praga V-12 engine was reportedly making good progress and pre-production examples for flight investigation were expected imminently. Flars planned to install the engine in the Lloyd 40.07 (Type KF 2) battleplane, identical in outward appearance to the 40.06 (Type KF 1), to compare the characteristics of the two different propulsion systems. Lloyd commenced work on the 40.07 prototype on 13 February 1916. Manufacture of the wings and fuselage, reported nearly complete, was suspended in July 1916 owing to difficulties encountered by the Erste bohmisch-mahrische Maschinenfabrik "Praga," who despite repeated urging by Flars, were unsuccessful in delivering a workable engine. As a result, Flars cancelled the Lloyd 40.07 project in the summer of 1917.

Lloyd 40.07 Specifications
Engine: 350 hp Praga
Wing: Span Upper 19.64 m (64.43 ft)
Span Lower 18.05 m (59.22 ft)
Chord Upper 2.50 m (8.20 ft)
Chord Lower 2.50 m (8.20 ft)
Dihedral Lower 4 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 2.50 m (8.20 ft)
Total Wing Area 72.4 sq m (779 sq ft)
General: Length 10.82 m (35.50 ft)
Height 3.60 m (11.81 ft)
Loaded Weight 2660 kg (5865 lb)

Lloyd 40.15

  Design work on the unorthodox 40.15 triplane fighter, powered by a 185 hp Daimler (MAG) engine, began in late summer 1917. Extant three-view drawings, dated 12 September 1917, portray a rather ungainly aircraft with several unique features such as might be expected from Lloyd. The wings were fully cantilevered and indications are that they were of mixed veneer and fabric construction. Rotating wingtip ailerons were fitted to the middle wing and the lower wing was mounted behind the undercarriage struts. The fuselage longerons were shaped to conform to the wing section to provide a smooth interface where the wings joined the fuselage. This feature was patented by Bier in 1919. Twin machine guns were mounted within reach of the pilot.
  Information regarding this intriguing prototype is sparse. According to Flars records, the 40.15 triplane was delivered in December 1917. Another reference, dated March 1918, reported the triplane in process of being assembled, leading to the speculation that it may have been rebuilt. Since flight and performance data is lacking, it is believed that extensive testing did not take place.

Lloyd 40.15 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 7.60 m (24.93 ft)
Span Middle 5.80 m (19.03 ft)
Span Lower 4.20 m (13.78 ft)
Chord Upper 1.64 m (5.38 ft)
Chord Middle 1.27 m (4.17 ft)
Chord Lower 1.00 m (3.28 ft)
Gap Upper 1.34 m (4.40 ft)
Gap Lower 0.80 m (2.62 ft)
Stagger Upper 1.34 m (4.40 ft)
Stagger Lower 0.80 m (2.62 ft)
Total Wing Area 22.2 sq m (239 sq ft)
General: Length 7.10 m (23.29 ft)
Height 2.82 m (9.25 ft)
Track 1.60 m (5.25 ft)
Loaded Weight 900 kg (1985 lb)


Lloyd 40.16

  Drawings and specifications for the Lloyd 40.16, completed in September 1917, show a fighter configured to maximize the view in all directions. The wing cellule was given a large amount of stagger and the outer wing struts were eliminated. The wings were supported by four broad, slanted struts running to the plywood-covered fuselage. As originally conceived, the design had rotating wing-tip ailerons and veneer wings, but when the prototype was rolled out in December 1917, photographs show conventional ailerons and wings of composite veneer and fabric construction. As in the 40.15, the upper fuselage longerons conformed to the wing section.
  Although designed for the 220 hp Benz (Mar) engine, Flars allocated a new 185 hp Daimler (MAG) engine on 27 May 1918 in preparation for the July Fighter Evaluation at Aspern. Here the 40.16 was inspected by fighter pilots, but it received no mention in the flight records nor in the pilots' assessments. Further details are lacking.

Lloyd 40.16 Specifications
Engine: 220 hp Benz (Mar)
Wing: Span Upper 8.58 m (28.15 ft)
Span Lower 7.60 m (24.93 ft)
Chord Upper 1.50 m (4.92 ft)
Chord Lower 1.30 m (4.27 ft)
Gap 1.53 m (.5.02 ft)
Stagger 1.35 m (4.43 ft)
Total Wing Area 24.53 sq m (269 sq ft]
General: Length 6.92 m (22.70 ft)
Height 2.58 m (8.46 ft)
Track 1.50 m (4.92 ft)
Loaded Weight 1000 kg (2205 lb)


Lloyd 40.17 to 40.20

  On 26 June 1918, Flars awarded Lloyd a contract for four experimental single-seat fighter biplanes to be powered either by 200/230 hp Daimler or Hiero engines and armed with twin machine guns. Static calculations, checked by Flars in July 1918, were returned to Lloyd with the comment that the lower wing did not meet the structural strength requirement. At the end of October 1918, all four prototypes were reported ready to commence flight testing at Aszod. Further details are lacking.

Lloyd 40.11

  In designing the veneer-winged 40.11 prototype, chief engineer Melczer departed from DFW-inspired aircraft and created a more compact airframe which, by careful attention to detail, was light, strong and handsomely streamlined. Design studies began in late spring 1916 and the 40.11, powered by a 160 hp Daimler engine, was under construction in August. The maiden flight, performed in October 1916, demonstrated that "the 40.11 possessed good speed and performance." In November 1916, Flars engineers scrutinized the 40.11 and specified various changes prior to issuing the production release. Brought up to frontline standard, the 40.11 was given the designation Lloyd C.V 46.01 and dispatched to Flik 13 on the Russian Front. On 4 October 1917, pilot Zugsfuhrer Adolf Wiltsch and Oberleutnant Roman Schmidt, flying the 46.01, shot down a single-seat fighter for their first and third victories respectively. 46.01 was later assigned to Flek 1 in Ujvidek as a trainer and in 1918, served as a liaison aircraft with Fliegerzug 1 in Lublin.

Lloyd 40.11 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 11.25 m (36.91 ft)
Span Lower 11.00 m (36.09 ft)
Chord 1.60 m (5.25 ft)
Upper Gap 1.85 m (6.07 ft)
General: Length 7.25 m (23.79 ft)


Lloyd 40.13 and 40.14

  40.13 and 40.14, were ordered for flight trials. Derived from the C.V, the all-wood design had a smaller wingspan and a deeper fuselage with a raised observer's cockpit to provide a wide field of fire. Forward armament consisted of twin machine guns. The recently-available 220 hp Benz (Mar) engine, manufactured under license by Automobil A.G. "Marta" of Arad, supplied the power. Mindful of the delays incurred in manufacturing the veneer wing, Lloyd provided four sets of interchangeable wing cellules, two for each prototype, for comparative tests.
  Intended for the 40.13, cellule A (almost identical to the C.V wing) was rejected outright and the prototype was test flown with cellule B, a single-bay, wire-braced, veneer wing of reduced span and area. Prototype 40.14 performed flight trials with cellules C and D, both low-aspect ratio wings of greater area and devoid of wire bracing. A Vee-strut running from the lower wing to the fuselage provided support. Unlike the B cellule, the C and D upper wings were of one piece. Cellule D was unique in that the rear section of the lower wing was fabric covered. On 21 and 29 May 1917, Flars engineers inspected the partially-completed airframes and suggested a number of minor improvements prior to flight tests.
  After engine installation in June 1917, the performance of the 40.13 proved slower than expected and it was returned to the factory for modification. In spite of Flars opinion expressing "no particular confidence or expectation with regard to performance," the program remained active. The more powerful 250 hp Benz (Mar) engine was installed in both prototypes. The 40.13 was timed for speed in March 1918 and, as late as August-September 1918, trials continued at Aspern and Fischamend.
  Prototype 40.14, first flown in July 1917, underwent an exhaustive program to investigate the characteristics of the C and D wing cellules, but results are not known. The 40.13 and 40.14 were reported at Aspern in September 1918 and offered for sale to Czechoslovakia in April 1920.

Lloyd 40.13 Specifications ('B' wings)
Engine: 220 hp Benz (Mar)
Wing: Span Upper 9.42 m (30.91 ft)
Span Lower 8.20 m (26.90 ft)
Chord Upper 1.65 m (5.41 ft)
Chord Lower 1.58 m (5.18 ft)
Dihedral Lower 2 deg
Sweepback Upper 8 deg
Sweepback Lower 8 deg
Gap 1.56 m (5.12 ft)
Stagger 0.40 m (1.31 ft)
Total Wing Area 22.5 sq m (242 sq ft)
General: Length 7.21 m (23.65 ft)
Height 2.78 m (9.12 ft)
Useful Load 220 kg (485 lb)
Loaded Weight 1200 kg (2646 lb)

Lloyd 40.14 Specifications ('C' Wings)
Engine: 220 hp Benz (Mar)
Wing: Span Upper 8.60 m (28.21 ft)
Span Lower 8.50 m (27.89 ft)
Chord Upper 1.82 m (5.97 ft|
Chord Lower 1.82 m (5.97 ft)
Dihedral Lower 2 deg
Sweepback Upper 4.1 deg
Sweepback Lower 4.1 deg
Gap 1.60 m (5.25 ft)
Stagger 0.42 m (1.38 ft)
Total Wing Area 25.5 sq m
General: Length 7.21 m (23.65 ft)
Height 2.78 m (9.12 ft)
Loaded Weight 1200 kg (2646 lb)
Maximum Speed: 180 km/hr (112 mph)
Climb: 1000m (3,281 ft) in 4 min

Lloyd 40.14 Specifications ('D' Wings)
Engine: 220 hp Benz (Mar)
Wing: Span Upper 8.60 m (28.21 ft)
Span Lower 8.60 m (28.21 ft)
Chord Upper 2.04 m (6.69 ft)
Chord Lower 2.04 m (6.69 ft)
Dihedral Lower 2 deg
Sweepback Upper 4.06 deg
Sweepback Lower 4.06 deg
Gap 1.60 m (5.25 ft)
Stagger 0.59 m (1.94 ft)
Total Wing Area 29.03 sq m (312 sq ft)
General: Length 7.21 m (23.65 ft)
Height 2.78 m (9.12 ft)
Loaded Weight 1220 kg (2690 lb)
Maximum Speed: 180 km/hr (112 mph)
Climb: 1000m (3,281 ft) in 4 min


Lloyd C.V Series 46

  The Lloyd C.V project was first mentioned in the LFT aircraft production list of July 1916. At the time the 40 C.V biplanes were ordered from Lloyd and WKF in December 1916, Flars exhorted Lloyd to expedite the prototype trials (40.11) and the C.V design work "in order to begin manufacture at the earliest date." In all, Flars approved production orders totalling 144 C.V aircraft in the following sequence:
Qty Manufacturer Series Number Engine Order Date
24 Lloyd 46.01-24 Dm 185 13 December 1916
24 Lloyd 46.25-48 Dm 185 12 February 1917
48 Lloyd 46.51-98 Bz 220(Mar) 18 January 1917
16 WKF 82.01-16 Bz 220(Mar) 21 December 1916
32 WKF 82.17-48 Bz 220(Mar) 18 January 1917
  The designers were able to achieve a significant performance increase by careful attention to weight reduction and streamlining. Each wing panel was composed of 14 spanwise stringers (in place of wing spars) equally-spaced around seven wing ribs and covered by a 1.2mm (0.04in) veneer skin polished to a high finish. Designed with semiskilled labor in mind, the wing construction was time-consuming but, on the other hand, very robust and capable of withstanding much abuse. However, unforeseen difficulties arose when the C.V reached the Front. If holed by shrapnel, the veneer skin was prone to peel back in the slipstream. The veneer covering was difficult to repair (nor had instructions been issued) and even slightly-damaged wings had to be exchanged at rear-area depots. Moisture condensation on the interior wing surface could cause warping or delamination that was impossible to detect. The C.V was armed with an observer's gun and sometimes with a Type II VK gun canister. Aircraft 46.25 was tested with a synchronized machine gun in June 1917, but it was not adopted as a standard feature. The camera and wireless equipment were installed behind the observer's position. A 50 kg (110 lb) bomb load could be carried in lieu of the observer.
  Static testing was completed on 24 February 1917. The production airframes were inspected on 10 March by Flars engineers who expressed disappointment that "the company, in spite of repeated urgings, had not presented a single airframe on which the deficiencies listed in the November 1916 inspection were corrected." Contractually the company was scheduled to deliver 46 aircraft by early February 1917, but the first five aircraft were not accepted until July, the majority following in August-September 1917. Of the 48 ordered, twenty C.V aircraft were accepted without engines since the Aviatik C.I, also built by Lloyd, was given priority for the 185 hp Daimler engine. To investigate compatibility, a 200 hp Hiero engine was installed and tested in aircraft 46.02.
  In September 1917, the first Lloyd C.V series 46 biplanes began to reach squadrons on the Eastern Front - eventually comprising Fliks 1, 9, 11, 13, 18, 22, 25, 26, 27, 30, 36/D, and 52/D. The initial reaction was mixed. Although speed and maneuverability were praised, pilots complained that the wheel control and unfamiliar rudder pedals were inappropriate for the very sensitive control response. The pedals, an innovation specified by Flars, were replaced by a normal rudder bar. In October 1917, a staff paper summed up the C.V: "Robustly built, very maneuverable, lateral stability good but longitudinal stability poor. Tail-heavy in a climb and excessively nose-heavy in a glide." The C.V, clearly unsuited for novice and average pilots, was pronounced a "handful" even by experienced veterans.
  On the Italian Front where many airfields were situated in mountain valleys, further removed from the combat zone than was customary on the Western Front, the C.V's usefulness was limited by its short range. Given the two-hour fuel supply, pilots had cause for anxiety when operating over mountainous terrain, where an forced landing was synonymous with crashing. In the main, the C.V was used as a communication machine or as an advanced trainer at the two field flying schools.

Lloyd C.V Series 46 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 11.19 m (36.71 ft)
Span Lower 11.00 m (36.09 ft)
Chord Upper 1.58 m (5.18 ft)
Chord Lower 1.60m (5.25 ft)
Dihedral Lower 2 deg
Sweepback Upper 5 deg
Sweepback Lower 5 deg
Gap 1.85 m (6.07 ft)
Stagger 0.35 m (1.15 ft)
Total Wing Area 27.63 sq m (297 sq ft)
General: Length 7.22 m (23.69 ft)
Height 3.00 m (9.84 ft)
Loaded Weight 1125 kg (2481 lb)
Maximum Speed: 165 km/hr (102.5 mph)
Climb: 1000m (3,281 ft) in 4 min 15 sec
3000m (9,843 ft) in 17 min
4600m (15,092 ft) in 40 min


Lloyd C.V Series 46.5

  With the availability of the 220 hp Benz(Mar) engine in late 1916, a total of 96 Lloyd C.V biplanes using this engine were ordered from Lloyd and WKF. The task of modifying the C.V airframe was assigned to WKF engineers, who encountered engine development problems which delayed the frontline introduction of the Lloyd series 46.5 machines until November 1917. The Lloyd acceptance flights, primarily flown by test pilot Antal Feher at Aszod, began on 12 November 1917 and ended on 19 March 1918. Because the Brandenburg C.I(U) series 169 were accorded priority, approximately ten C.V series 46.5 aircraft were delivered without engines.
  When it arrived on the Italian Front in late 1917, the C.V series 46.5 was reported by Fliks 6, 27, and 37 as extremely difficult to fly, possessing an excessively steep glide and high landing speed. Unless the landing was executed with "verve," the C.V had a propensity to stall without warning. The army staff reported that "even experienced pilots, including the very best, have great difficulty landing." Yet, as always, there were exceptional pilots who could look back with some satisfaction at having mastered the aircraft's vagaries. According to Feldpilot Franz Zuzmann, who piloted the C.V on airmail runs to the Ukraine, "The machine needed the right touch. You had to be a good pilot. The C.V reacted like a fighter to the slightest control movement, especially when landing. You had to touch down with lots of speed or else you could easily crash. The aircraft was sensitive at low speeds. You had to be fearless." The antipathy towards the type explains why it was soon relegated to communication or training duties.
  On 12 July 1918, a LFT command decided to withdraw all Lloyd C.V biplanes from frontline units and assign 20 as trainers to the Feldfliegerschule Campoformido. However, in August 1918 the remaining C.V biplanes in field units were ordered withdrawn. Those not used as ground instruction airframes were placed in storage. As of October 1918, 62 C.V biplanes were reported in damaged condition, either at mechanics' schools or in storage depots.
  After the war, 55 Lloyd C.V biplanes were offered for sale. At least five served with the Polish Air Force 2nd Squadron in November-December 1918 and several were flown by Hungarian and Ukrainian units in the immediate post-war period.

Lloyd C.V Series 46.5 Specifications
Engine: 220 hp Benz (Mar)
Wing: Span Upper 11.19 m (36.71 ft)
Span Lower 11.00 m (36.09 ft)
Chord Upper 1.58 m (5.18 ft)
Chord Lower 1.60 m (5.25 ft)
Dihedral Lower 2 deg
Sweepback Upper 5 deg
Sweepback Lower 5 deg
Gap 1.85 m (6.07 ft)
Stagger 0.10 m (0.33 ft)
Total Wing Area 27.63 sq m (297 sq ft)
General: Length 7.22 m (23.69 ft)
Height 3.00 m (9.84 ft)
Loaded Weight 1185 kg (2613 lb)
Maximum Speed: 170 km/hr (106 mph)
Climb: 1000m (3,281 ft) in 4 min
2000m (6,562 ft) in 10 min 16 sec
3000m (9,843 ft) in 16 min 15 sec


WKF 80.09

  To forestall Flars criticism and the possibility of a penalty payment, WKF installed a standard 185 hp Daimler engine in a Lloyd C.V(WKF) series 82 airframe to demonstrate that the poor performance of the Benz-powered version was the fault of the engine and not of WKF engineering. The test aircraft was designated 80.09. After flight evaluation, the airframe was delivered to Aspern on 9 October 1917, and assigned to the mechanic's school at in Wiener-Neustadt on 1 March 1918 where it was written-off after a crash in May or July 1918. The airframe was stored at Aspern in August 1918. The designation 82.50, also assigned to the 80.09, does not appear to have been used in practice.


Lloyd C.V(WKF) Series 82

  When the 220 hp Benz(Mar) engine, based on the reliable German Benz Bz.IV and built under license by Automobil AG "Marta" in Arad, became available in late 1916, it was chosen to power the WKF-built Lloyd C.V. On 21 December 1916, WKF signed a contract for 16 biplanes, of which eight were specified as "Benz trainers" to familiarize aircrews with the new engine. An additional 48 aircraft were ordered on 18 January 1917, making a total of 64, with deliveries scheduled to begin in January 1917. Because of the delay incurred by engine problems, Flars later reduced the production total to 48 aircraft. These were designated Lloyd C.V(WKF) 82.01 to 82.48.
  Oberingenieur Schieferl of WKF was responsible for adapting the C.V airframe for the Benz engine. Progress dragged because the new engine required frequent repair and replacement of the carburetor, water pump, cylinders, and pistons. The cooling system had to be totally re-built, which according to WKF "added an additional 180 kilos (397 lb) plus an enormously large radiator to achieve proper engine operation." The first completed C.V(82.02) after being inspected by Flars on 24 March 1917, was dispatched to Lloyd for final outfitting. When commissioned on 18 May 1917, the aircraft was rejected because of recurrent engine failures. In spite of the best efforts of Marta engineers through June 1917, the C.V failed the speed and climb tests on 2 July 1917. To demonstrate that the company was faultless, WKF installed a standard 185 hp Daimler engine in a C.V airframe for testing (see 80.09). By August 1917, the engine problems were finally brought under control and military acceptances were in full swing, a welcome relief as the factory was jammed with completed airframes which obstructed production flow.
  The added cooling system weight adversely affected the already critical flight characteristics of the C.V, originally designed for the lighter 185 hp Daimler engine. The Benz-engined version was extremely tricky to fly, requiring a deft touch to avoid accidents. Even the most experienced and prudent pilots showed great respect (see Lloyd C.V series 46). Beginning in September 1917, most of the WKF-built C.V biplanes were sent to units on the Russian Front where operational conditions were less demanding. Here the aircraft saw sporadic service until the cessation of hostilities with Russia in December 1917. A few machines served with Fliks 6/F and 64/F on the Albanian Front through the summer of 1918. Several C.V(WKF) biplanes were flown as advanced trainers by Fliks 19/F and 66/D on the Piave and by Fleks 6, 8, 13, and 14. Four were attached to the postal flight to deliver mail to the army units in the Ukraine. As of October 1918, thirty-one damaged C.V (WKF) airframes were in storage, an indication of the high accident rate associated with this aircraft.

Lloyd C.V(WKF) Series 82 Specifications
Engine: 220 hp Benz (Mar)
Wing: Span Upper 11.19 m (36.71 ft)
Span Lower 11.00 m (36.09 ft)
Chord Upper 1.60 m (5.25 ft)
Chord Lower 1.60 m (5.25 ft)
Sweepback Upper 5 deg
Sweepback Lower 5 deg
Gap 1.85 m (6.07 ft)
Stagger 0.10 m (0.33 ft)
Total Wing Area 27.12 sq. m (292 sq ft)
General: Length 7.11 m (23.33 ft)
Height 3.13 m (10.27 ft)
Track 1.80 m (5.91 ft)
Empty Weight 860 kg (1896 lb)
Loaded Weight 1214 kg (2677 lb)
Climb: 1000m (3,281 ft) in 5 min 6 sec
3000m (9,843 ft) in 22 min 8 sec

When Jakob Lohner & Co began to build aircraft in 1909, the new enterprise formed an ideal adjunct to its coach and auto chassis manufacturing business. The company, founded in 1821 and renamed Jakob Lohner & Co in 1868, was managed by Ludwig Lohner from 1892 until his death in 1925. Lohner was the first company to build automobiles in Austria, assisted by Ferdinand Porsche (of Volkswagen fame) who was hired in 1899 to develop an electric automobile. Over 300 examples were built, notably fire engines, some of which were still chasing fires in the late Twenties. In 1906 Porsche became technical director of the newly-organized Oesterreichische Daimler Motoren AG (known as Austro-Daimler) but maintained close ties with Lohner regarding aircraft engine development.
  Lohner's first aircraft were custom-built models commissioned and sometimes designed by wealthy, would-be aviators. Beginning with rudimentary gliders, Lohner's activity soon expanded into powered aircraft, of which the biplane designed by Rittmeister Hans Umlauff von Frankwell, an army officer and graduate engineer, was particularly successful. Not only did Umlauff provide technical expertise, but he guided the Lohner shop manager, Karl Paulal, through the intricacies of aircraft construction. Despite the fact that Paulal lacked formal engineering training, his intuitive grasp of aircraft design made him chief aircraft designer at Lohner.
  Umlauff's biplane, completed in the summer of 1910, was promising enough for Lohner and Austro-Daimler (who contributed a new light-weight 65 hp aero engine designed by Porsche) to jointly launch an improved version. The Lohner-Daimler Pfeilflieger (arrow flyer), characterized by an exaggerated sweepback (a Lohner trademark), made its maiden flight on 18 October 1910. Umlauff, piloting the Pfeilflieger, hit the headlines with a series of notable flights and achieved fame by winning the coveted Vienna-Budapest-Vienna prize on 24 June 1911. The Pfeilflieger, of which 212 were built in various versions through 1916, formed the bulk of Lohner's army aircraft business.

Lohner Pfeilflieger AD 355

  The Pfeilflieger AD 355, powered by a 120 hp Daimler engine, was built to compete in the Second International Flugmeeting at Aspern, during the course of which on 17 June 1913, Karl Illner established a world record of 5010 meters (16,437 ft) carrying two passengers, thus earning him third place against strong French competition. Pfeilflieger AD 355 was offered to the LA in May 1914, but its purchase was rejected notwithstanding Uzelac's request that a second aircraft join the aging Aspern for training purposes. With the start of hostilities, AD 355 less engine was procured by the LA on 15 August 1914. Further information is lacking.

Lohner Pfeilflieger (AD 355) Specifications
Engine: 120 hp Daimler
Wing:
Span Upper 13.70 m (44.95 ft)
Total Wing Area 42.0 sq m (452 sq ft)
General:
Length 7.90 m (25.92 ft)
Height 3.00 m (9.84 ft)
Empty Weight 620 kg (1367 lb)
Maximum Speed: 100 km/hr (62 mph)


Lohner Pfeilflieger AD 551

  This aircraft was purchased by the LA on 17 January 1915 with ten other aircraft according to Lohner records. Photographs and information are lacking.


Lohner Pfeilflieger AD 565

  Pfeilflieger AD 565, fitted with a 100 hp Mercedes engine, was delivered to the LA on 17 August 1914 and a second time (after repair?) on 27 January 1915. There is no record of service use or photographs.


Lohner Pfeilflieger "Helvetia" AD 566

  On 10 February 1914, Lohner began work on three Type C Pfeilfliegers, powered by the 85 hp Hiero engine, intended for competition use. One machine, christened Helvetia, flown at Aspern on 21 March 1914 by Oberleutnant Karl Banfield, was exhibited at the annual Berne Fair and demonstrated by Banfield in the Swiss military aircraft competition in April 1914. It was rejected and returned to Vienna. On 15 August 1914, the LA purchased Helvetia less engine. Further information is lacking.
  


Lohner Pfeilflieger AD 752

  Lohner records show this aircraft was delivered to the LA on 27 January 1915. Photographs and information are lacking.


Lohner 10.04

  At the beginning of the war, the LA purchased every available aircraft it could lay its hands on. One such was Pfeilflieger (AD 606) which Paulal had designed for the newly-developed 250 hp Daimler V-12 engine for competition in the Third International Flugmeeting at Aspern. Lohner and Daimler engineers worked feverishly to prepare the biplane, but plagued by recurrent engine problems which Porsche vainly attempted to rectify, Oberleutnant Karl Banfield (competition No. 21) failed to win any prizes. Despite the poor showing, the large Pfeilflieger with its massive V-12 engine created a sensation when it first appeared on the Aspern aerodrome. Pfeilflieger AD 606, purchased less engine on 15 August 1914, initially received the LA designation Lohner D-250, and in February 1915, the number 10.04 was assigned. Used as a trainer, the Lohner 10.04, now powered by a 120 hp Daimler engine, was written-off on 15 November 1915.

AD Lohner 10.04 (AD 606) Specifications
Engine: 120 hp Daimler
Wing: Span Upper 14.40 m (47.24 ft)
Span Lower 9.90 m (32.48 ft)
Chord Upper 1.95 m (6.40 ft)
Chord Lower 1.80 m (5.91 ft)
Total Wing Area 41.07 sq m (442 sq ft)
General: Length 8.60 m (28.21 ft)
Height 3.50 m (11.48 ft)
Empty Weight 1050 kg (2315 lb)
Loaded Weight 1300 kg (2867 lb)

  

Lohner 10.05

  Among the competition Pfeilfliegers financed by Lohner and MLG was Pfeilflieger AD 578, construction of which began on 24 March 1914. The Pfeilflieger, powered by a 120 hp Daimler engine, was flown in the Schicht Flug by Oberleutnant Karl Banfield (competition No.9) who, prohibited as an Army officer from using his name, used the pseudonym 'Mumb.' Although the aircraft had been expected to win the speed competition, Banfield had to be content with second prize. It is believed the AD 578 was the same as the Lohner D-R (Daimler Renndoppeldecker - racing biplane) which was purchased less engine in August 1914 and assigned number 10.05 in February 1915. According to von Mises' diary a new 120 hp Daimler engine was installed in May 1915. 10.05 served with Flek 1 and 6 as a trainer before being written-off in June 1915.


Lohner 10.06

  Encouraged by the success of the first Lohner-Daimler Pfeilflieger in 1911, Lohner began work on the Heeres Konkurrenz Apparat (army competition machine - AC 822) on 1 March 1912. Powered by a 120 hp Daimler engine, Aspern made its maiden flight on 3 May 1912 piloted by Oberleutnant Philipp Blaschke Ritter von Zwornikkirchen. Competing in the Berlin-Vienna long-distance race, Blaschke took second prize on 10 June 1912 (although he had to be pushed across the finish line), beaten by the sole pilot to finish by air - Hellmuth Hirth in a Rumpler Taube. In the ensuing First International Flugmeeting at Aspern, Blaschke and passenger Karl Banfield established two world records for rate of climb and altitude, reaching 4360 meters (14,305 ft) on 29 June 1912. In recognition of the achievement Emperor Franz Joseph, in a magnanimous gesture, bestowed a monetary sum equal to the obligatory dowry, permitting Blaschke to finally wed his betrothed. French competitors, accustomed to nimble, light aircraft, derided the massive Aspern as "the flying chateau."
  The LA purchased Aspern, the first of a long line of Pfeilfliegers operated by the air service, on 24 July 1912, using it primarily to train pilots in handling the 120 hp engine. At mobilization, Aspern was assigned to Flik 14 on the Eastern Front, but no record of operational service has been found. Aspern, given number 10.06 in February 1915, remained unreported until October 1918, when it was listed as stored in damaged condition at Fischamend, possibly having been preserved for the planned LFT collection of historic aircraft.

Lohner 10.06 (AC 822) Specifications
Engine: 120 hp Daimler
Wing: Span Upper 15.80 m (51.84 ft)
Span Lower 10.80 m (35.43 ft)
Chord Upper 1.90 m (6.23 ft)
Chord Lower 1.70 m (5.58 ft)
Total Wing Area 44.0 sq m (473 sq ft)
General: Length 9.80 m (32.15 ft)
Height 3.30 m (10.83 ft)
Empty Weight 725 kg (1599 lb)
Loaded Weight 1095 kg (2414 lb)
Maximum Speed: 110 km/hr (68 mph)
Climb: 1000m (3,281 ft) in 10 min


Lohner 10.10 (new)

  Construction of Pfeilflieger AD 567 - one of the three Lohner built for the Schicht Flug (April 1914) - began on 19 February 1914. Powered by 140 hp Hiero engine, it was flown by Oberleutnant Robert Baar (using the pseudonym Bareth, competition No.8), who won the speed and distance prizes and took second prize in the reliability competition. AD 567, less engine, was purchased by the LA on 15 August 1914. This is possibly the same aircraft as the Lohner L-140 which served with Flik 6 in the Balkans until 20 December 1914 when it made a forced landing in the Adriatic.
On 31 March 1915, an LA directive ordered aircraft L-140 to be given the designation 10.10 which had been previously assigned to an Etrich Taube trainer. Further information is lacking.

Lohner 10.10 (new) Specifications
Engine: 140 hp Hiero
Wing: Span Upper 13.60 m (44.62 ft)
Span Lower 9.00 m (29.53 ft)
General: Length 8.80 m (28.87 ft)
Height 3.50 m (11.48 ft)
Empty Weight 725 kg (1599 lb)
Loaded Weight 990 kg (2183 lb)
Maximum Speed: 130km/hr(81 mph)


Lohner 10.14

  In the Third International Flugmeeting, Lohner entered a brand-new Meeting Apparat 1914 (provisionally identified as AD 580) powered by a "special" 140 hp Daimler engine. Company pilot Viktor Wittmann (competition No.26) only managed fifteenth place in the overall standings because of engine problems. Lohner sold Pfeilflieger AD 580 less engine to the LA on 27 January 1915. The aircraft, assigned the military designation D 26, was flown by Flik 1 on the Serbian Front. On 31 July 1914, D 26 grazed a chimney while landing but fortunately neither Oberleutnants Raoul Stojsavljevic nor Franz Kabelac were injured. In February 1915, D 26 received the designation 10.14 and was last reported in 1915 serving as a trainer with Flek 3 in Graz-Thalerhof.


Lohner 10.16

  The Lohner Pfeilflieger (AD 553), powered by a 90 hp Daimler engine, was built to compete in the 1914 Schicht Flug. To prepare for the competition (in which he would fly the new Pfeilflieger AD 567) Oberleutnant Baar used this machine for altitude and duration practice flights in early April 1914. In the Schicht Flug AD 553 was flown by Viktor Wittmann (competition No. 10), winning the reliability prize. In June 1914 at the Third International Flugmeeting, Edmund Sparmann piloting AD 553 (competition No.25) was awarded the War Ministry prize for the best all-round results achieved by a citizen flying an indigenous aircraft.
  AD 553 was purchased by the LA in August 1914 and assigned the number 10.16 in February 1915. According to operational records, Pfeilflieger 10.16 served with Flik 2 on the Italian Front from 7 July to September 1915 and was written-off in January 1917.


Lohner B.I Series 11

  The stage was set for military production after Aspern’s (later 10.06) record-breaking feats had demonstrated the usefulness of the Pfeilflieger design - an aircraft that could compete with Europe's best. Because of budget restrictions the Austrian and Hungarian national Aero Clubs spearheaded a fund-raising campaign "to build an Austro-Hungarian air fleet destined to stand proudly beside those of Germany and France." Lohner, assured of financial support, began the construction of four military Pfeilfliegers known as the Lohner Type B. Work on the first, named Bravo (AC 960), powered by a 65 hp Daimler engine and probably intended for training, began on 11 July 1912. Construction of Bora (AC 982) and Butterfly (AC 983), powered by the 90 hp Daimler engine and equipped for full military use, began on 23 July 1912. Bravo was delivered on 27 September 1912 in time for Blaschke to demonstrate the graceful biplane to enthusiastic crowds at the Offiziersfliegen in Wiener-Neustadt on 6 October 1912. Bora was completed on 16 October 1912 and delivered to the LA on 27 November 1912. Butterfly was completed on 27 November and delivered in December 1912. The fourth Pfeilflieger was Cyklon, a lightened Type B airframe powered by the new 85 hp Hiero engine. Cyklon was the forerunner of the Lohner Type C (see Lohner B.II Series 12).
  The flight and performance characteristics were very encouraging and on 26 November 1912, the LA formally purchased Bora, Bravo, and Butterfly and ordered 28 Type B biplanes (AD 201-228) powered by the 90 hp Daimler engine. The last production aircraft was accepted on 14 May 1913, one month behind schedule. With time, the LA insisted on modifications that added about 100 kg (220 lb) weight, causing Lohner to warn of the impossibility of meeting performance guarantees. Beginning with the seventh aircraft an improved forged-steel undercarriage was fitted that, according to Lohner records, permitted a larger wing chord, adding 3.5 square meters (37.7 sq ft) of wing area. Starting with the ninth aircraft the fuselage was lengthened slightly. Having received basic training in the undemanding Etrich Taube monoplanes, pilots in preparation for taking a Type B aloft were told that "now flying would begin in earnest" and warned that "the sensitive controls required real flying skill." In truth, the flight characteristics were docile and easy to master by even an average pilot.
  The Type B aircraft were based at Flugparks around the empire. Extensive operational training service during the Balkan crisis caused heavy wear and tear. When Bandit was repaired in December 1913, Lohner replaced the original wing with a lightened, stronger cellule known as the "Spanish wing." The top wing halves were joined at the center line and supported by inverted-vee struts that eliminated the center-section cabane. The rounded ailerons were changed to a rectangular shape. The wing tips could be folded down for storage. The LA allocated funds to retrofit all Type B aircraft with a modified "Spanish wing." By 1 February 1914, seven aircraft had been so modified; one was fitted with the original "Spanish wing"; 14 had the old cellule and the rest were in repair.
  After the fatal wing failure of the Type C Pfeilflieger in March 1914, the Type B was also load tested. When ominous cracking sounds were heard, the test was halted in order to reinforce the cellule with additional bracing, but in the second try the wings failed well below the specified load factor. In fact, the entire airframe was pitifully understrength, leading the crash committee to conclude that "only the mediocre flight characteristics which demanded careful piloting had spared the pilots' lives." The LA grounded all Type B biplanes pending wing reinforcement. This work was assigned to Lohner and the Fischamend repair shop. The final blow fell on 28 April 1914, when Feuerwerker Georg Wally was killed because the fuselage of Bravo collapsed in mid-air. In a long memorandum, Uzelac placed the blame squarely on Lohner. The company, secure in its monopolistic position, had neglected to keep pace with modern aircraft engineering practices abroad. LA officers who had visited German and British factories criticized the poor detail workmanship throughout and use of defective materials. "Every officer sent abroad noticed the flawless wood used in aircraft construction, unlike the knot-rich wood used by Lohner for load-carrying members."
  On the first (partial) mobilization day, 25 July 1914, a total of 39 Army aircraft were in flyable condition, consisting of 30 Lohner B-types (of which 11 were in storage or repair), seven Lohner D-types (two in repair), and the Lohner C-01 and C-02 prototypes.
  Of the first war experiences, Flik 2 on the Serbian Front and Fliks 7, 8, and 14 on the Russian Front reported that the Type B machines were barely capable of performing operational tasks. All but two of Flik 2's complement of six Type B biplanes were out of service or in repair in August 1914, and six replacement machines arrived in poor shape, having been in storage since December 1913. The Fifth Army submitted a report in August 1914 deploring the fragility of the aging B-types. It took the total dedication of Flik 2 personnel, commanded by Oberleutnant Baar, to keep two patched up aircraft airborne albeit with rapidly decreasing performance. As soon as German replacement aircraft became available in September-October, the Type B disappeared from the Front.
  In February 1915, the B-types were designated Lohner B.I series 11 and allocated numbers 11.01 to 11.31. Since this represented almost the total number of B-types built, it is apparent that combat losses were negligible and badly-damaged machines were rebuilt rather than written-off. Benign flight characteristics made the B.I acceptable as a primary trainer; consequently, 16 B.I machines were dispatched to Fischamend in late 1915 to be fitted with a stronger wing cellule and dual controls designed by Ingenieurleutnant Karl Saliger. In addition, Fischamend built 20 Type B dual-control trainers during 1916. In the process, the new and rebuilt aircraft received the designation Lohner B.I(Fd) series 73. The B.I(Fd) series 73 trainers remained in service through 1918 with Fleks 1, 2, 3, 6, and 7. The last original Lohner B.I aircraft, 11.18, was removed from service in June 1917 for the planned aircraft museum at Fischamend.

Lohner B.I Series 11 Specifications
Engine: 90 hp Daimler
Wing: Span Upper 13.40 m (43.96 ft)
Span Lower 9.60 m (31.50 ft)
Chord Upper 1.88 m (6.17 ft)
Chord Lower 1.83 m (6.00 ft)
Gap 1.90 m (6.23 ft)
Stagger 0.56 m (1.84 ft)
Total Wing Area 37.5 sq m (404 sq ft)
General: Length 8.50 m |27.89 ft)
Height 3.00 m (9.84 ft)
Empty Weight 630 kg (1389 lb)
Loaded Weight 970 kg (2139 lb)
Maximum Speed: 115 km/hr (71 mph)
Climb: 1000m (3,281 ft) in 12 min

List of Lohner Type B Aircraft
Works Number Name Delivery Date Stationed 1 Feb 14 New No. 8 Feb 15 Fischamend Number (a)
AC 960 Bravo 27 Sep 12 Flugpark 1 11.24
AC 982 Bora 16 Oct 12 Flugpark 8 11.21
AC 983 Butterfly 7 Dec 12 Flugpark 8 -
AD 201 Bellona 1 Feb 13 Flugpark 14 11.13 (b)
AD 202 Bajadere 3 Feb 13 - 11.02 73.02
AD 203 Bela 12 Feb 13 Flugpark 8 11.10 73.10
AD 204 Blitz 3 Mar 13 Flugpark 14 11.15 73.15
AD 205 Bandit 4 Mar 13 Flugpark 14 11.05 73.05
AD 206 Barbara 11 Mar 13 Flugpark 7 11.07 73.07
AD 207 Bomerang 12 Mar 13 Flugpark 7 11.20
AD 209 Boheme 15 Mar 13 Flugpark 2 11.17
AD 209 Baldur 19 Mar 13 Flugpark 8 11.04 73.04
AD 210 Boy 21 Mar 13 - 11.23
AD 211 Bombe 26 Mar 13 Flugpark 2 11.19
AD 212 Bella 9 Mar 13 Flugpark 2 11.11 73.11
AD 213 Brutus 2 Apr 13 - 11.27
AD 214 Bojar 3 Apr 13 Flugpark 2 11.18
AD 215 Barbar 4 Apr 13 Flugpark 14 11.06 73.06
AD 216 Bote 9 Apr 13 Flugpark 2 11.22
AD 217 Brunhilde 11 Apr 13 Flugpark 1 11.26
AD 218 Bulle 12 Apr 13 Flugpark 7 11.29
AD 219 Brigant 29 Apr 13 Flugpark 4 11.25 73.25
AD 220 Bob 29 Apr 13 - 11.16
AD 221 Baby 29 Apr 13 - 11.31
AD 222 Beduine 29 Apr 13 - 11.09 73.09
AD 223 Bertha 24 Apr 13 Flugpark 8 11.14
AD 224 Bub 27 Apr 13 Flugpark 2 11.30 (b)
AD 225 Bajazzo 3 May 13 Flugpark 14 11.03 73.03
AD 226 Beate 4 May 13 Flugpark 2 11.08 73.08
AD 227 Buddha 9 May 13 Flugpark 14 11.28
AD 228 Belisar 14 May 13 Flugpark 8 11.12 73.12
AD- B-1 - - 11.01 (c) 73.01
AD- B-30 - Flugpark 7 11.30 (b)
(a) A total of 16 Type B aircraft (14 above and 2 unidentified) were modified by Fischamend and placed in the B.I(Fd) 73.01 to 73.36 series.
(b) Although Bellona (AD 201) and Bub (AD 224) were lost in 1914, they were assigned a number in February 1915, the reason for which is not known. It is likely that aircraft B-30 received the number 11.30, but confirmation is lacking.
(c) Aircraft B-1 (11.01) has been listed as a replacement for Butterfly but confirmation is lacking.


Lohner (B.III) Series 13

  Karl Hiner's great success piloting the Pfeilflieger (AD 355), powered by the new 120 hp Daimler engine, at the Second International Flugmeeting in June 1913 was welcome news to the LA, who had ordered six Lohner Type D Pfeilfliegers powered by the same engine and configured as long-range reconnaissance aircraft with a specified flight duration of 10 hours. The Type D went into production on 7 May 1913 and the contract was signed on 25 June. The following aircraft were delivered between 24 August and 11 September 1913: Delibab (AD 356-13.04), Delphin (AD 357-13.01), Dental (AD 358-13.02), Don Juan (AD 359-13.03), Don Quichotte (AD 360), and Dreadnaught (AD 361).
  At the summer 1913 Kaiser Maneuvers, eleven emergency landings caused by erratic running engines led the LA to disassemble the Type D aircraft for storage at Fischamend until the problem was resolved. By December 1913 the Type D had been returned to Lohner and after modification five aircraft were reported in flying condition on 1 February 1914. As a precautionary measure following Elsner's crash (see the Lohner B.II series 12), a Type D airframe was also load tested and showed similar premature wing failure. Installation of additional wire bracing, recommended as an interim solution by Professor Knoller, rescinded the grounding order.
  In mid-1913, the LA began to investigate air-to-ground wireless communication and at the end of May 1914, Professor Dr Leopold Kann installed an experimental Telefunken-Siemens-Halske transmitter in Dental for flight evaluation. The 50 meter (164 ft) aerial caused some concern but it remained well clear of the elevator in flight. Ground signal reception was clear and ensuing spotting trials to direct artillery fire produced excellent results. Austro-Hungarian historians claim that this was the first successful direction of artillery fire from the air.
  Lohner reported on 18 July 1914 that the "planned reconstruction" (what was involved is not known) of six Type D plus one competition aircraft could not be completed until late autumn 1914. Pushed by the exigencies of war, the work was cancelled and four Type D Pfeilfliegers went to the Front with Flik 1. After rotted wing ribs were found in the course of routine inspection, the rear-area aircraft park replaced the ribs and wingtip sections. Two Type D aircraft were lost. Dreadnought, with Oberleutnants Hugo Schwab and Franz Kabelac aboard, was downed on 14 August by Russian troops because the aircraft was incapable of climbing over 500 meters (1640 ft). On 16 August, Oberleutnant Josef Flassig and Leutnant Engelbert Wolf lost their lives when Don Quichotte crashed due to wing failure. The news spread like wildfire through the LA, destroying the last vestige of confidence in Lohner aircraft. As a result, the four remaining Type D aircraft were grounded and scrapped.

Lohner (B.III) Series 13 Specifications
Engine: 120 hp Daimler
Wing: Span Upper 16.50 m (54.13 ft)
Span Lower 11.40 m (37.40 ft)
Chord Upper 2.09 m (6.86 ft)
Chord Lower 1.86 m (6.10 ft)
Gap 2.26 m (7.41 ft)
Stagger 1.05 m (3.44 ft)
Total Wing Area 49.4 sq m (532 sq ft)
General: Length 9.50 m (31.17 ft)
Height 3.50 m (11.48 ft)
Track 2.20 m (7.22 ft)
Empty Weight 755 kg (1665 lb)
Loaded Weight 1225 kg (2701 lb)
Maximum Speed: 130 km/hr (81 mph)
Climb: 1000m (3,281 ft) in 10 min


Lohner B.I(Fd) Series 73

  When the Lohner B.I series 11 biplanes were withdrawn from the Front in mid-1915, sixteen were converted by the Flugzeugwerk into dual-control trainers to take advantage of their docile flying qualities. After receiving a modified fuselage and a stronger wing cellule designed by Ingenieurleutnant Karl Saliger of Flars, the converted trainers were re-designated Lohner B.I(Fd) series 73. In December 1915, the Flugzeugwerk began to build 20 new Lohner B.I(Fd) trainers numbered 73.13, 14, 16-24, and 26-34. When production was completed in October 1916, the total B.I(Fd) series built were numbered 73.01 to 73.36. Power was supplied either by a 90 or 100 hp Daimler engine. The Fischamend-built B.I(Fd) biplanes served as transition trainers with Fleks 1-6 and 13 as well as Schulkompagnie 1 and 2. As of 1 July 1917, twenty were still in active school service.

Lohner B.I(Fd) Series 73 Specifications
Engine: 200 hp Hiero
Wing: Span Upper 14.00 m (45.93 ft)
Chord Upper 1.80m (5.91 ft)
Chord Lower 1.80 m (5.91 ft)
Sweepback Upper 17 deg
Gap 1.835-1.960 m (6.02-6.43 ft)
Stagger 0.40 m (1.31 ft)
Total Wing Area 43.7 sq m (470 sq ft)
General: Length 8.60 m (28.21 ft)
Height 3.40 m (11.15 ft)
Track 2.18 m (7.15 ft)
Empty Weight 740 kg (1632 lb)
Loaded Weight 994 kg (2192 lb)

Lohner 10.01 to 10.03

  After the Pfeilflieger Type C accident (see Lohner B.II series 12), the LA thoroughly tested each new design before approving production. Consequently, for static testing and flight trials, three prototypes of the improved Lohner Type E Pfeilflieger (AD 810 - AD 812) were ordered on 30 October 1914. Powered by the 100 hp Daimler engine, the first two aircraft, E-01 and E-02, were delivered on 10 December 1914 and E-03 on 21 January 1915. The designations were changed to 10.01-10.03 in February 1915. After passing military tests, the Type E was produced by Lohner as the B.III series 14 and by UFAG as the B.III (U) series 14.5.
  Serving as trainers, the Lohner E-01 (10.01) was written-off in October 1916 and the E-02 (10.02), the static load test airframe, later was flown by Fleks 2 and 4 through mid-1915 at least. From the outset the Lohner E-03 (10.03) prototype was modified, being equipped with a simplified wing cellule incorporating a thicker "Knoller profile." Later the complex Lohner undercarriage was redesigned with sprung axles replacing the shock-cord assembly. The E-03 (10.03) was flown as a trainer by Flek 4 until May 1915, when at the direction of Major von Umlauff, Lohner rebuilt the 10.03 by modifying the wings and installing a 100 hp Mercedes engine. As such the 10.03 became the prototype for the Lohner Type G and was assigned the designation B.IV 15.01 (see Lohner B.IV series 15 chapter).
  
Lohner 10.01 (AD 810) Specifications
Engine: 100 hp Daimler
Wing: Span Upper 13.60 m (44.62 ft)
Span Lower 9.10 m (29.86 ft)
Total Wing Area 31.9 sq m (343 sq ft)
General: Length 8.43 m (27.66 ft)
Height 3.48 m (11.42 ft)
Empty Weight 625 kg (1378 lb)
Loaded Weight 920 kg (2029 lb)
Climb: 1000m (3,281 ft) in 11 min


Lohner 10.07

  In April 1913, Lohner began the construction of a Gebirgsflieger (mountain flyer - AD 350), powered by a 80 hp Gnome rotary engine, designed to climb faster and operate at higher altitude than heavier aircraft with water-cooled engines. On 20 August 1913, shortly after completion, Uzelac test flew the machine which was delivered to the LA on 30 August 1913 under the designation "experimental machine G-1." Used as a trainer, it was based at Flugpark 3 in Gorz in February 1914. There is no record of wartime service.
  A second, private-venture Gebirgsflieger (AD 490) powered by a 100 hp Gnome, begun on 27 October 1913, was built in response to the success of the French rotary-engined aircraft at the Second International Flugmeeting. Because Lohner did not employ a full-time company acceptance pilot, it was not unusual for military pilots to carry out this task. On 27 February 1914, Oberleutnant Eugen Elsner performed the maiden flight which, according to a witness, demonstrated the plane's precise maneuverability, a rapid rate of climb, and high speed. Although built at the express wish of the LA, a subsequent lack of interest caused bitter recriminations. The machine did not participate in the two 1914 competitions. When purchased by the LA on 15 August 1914, it was designated LG-490 and entered training service with Flek 1 and later Flek 6. Numbered 10.07 in February 1915, the trainer was badly damaged on 2 December 1915 and written-off.

Lohner 10.07 (AD 490) Specifications
Engine: 100 hp Gnome
Wing: Span Upper 12.00 m (39.37 ft)
Span Lower 8.60 m (28.21 ft)
Chord Upper 1.56 m (5.12 ft)
Chord Lower 1.50 m (4.92 ft)
Total Wing Area 26.7 sq m (287 sq ft)
General: Length 7.80 m (25.59 ft)
Height 3.50 m (11.48 ft)
Empty Weight 460 kg (1014 lb)
Loaded Weight 780 kg (1720 lb)
Climb: 1000m (3,281 ft) in 8 min


Lohner 10.12

  Buoyed by the success of the Type B biplane, the LA requested Lohner to develop a lighter version with improved climbing ability for operation in mountainous terrain. A lighter engine was chosen, namely the four-cylinder 85 hp Hiero. Construction of the prototype known as the Gebirgsflieger Type C (mountain flyer - AD 353) was begun as a private venture on 4 April 1913. The prototype appeared at the Second International Flugmeeting at Aspern on 14 June 1913 for viewing only and was delivered to the LA in August. On 24 August 1913, crewed by Leutnant Hans Mandl and Oberleutnant Nikolaus Wagner Edler von Florheim, it became the second aircraft to fly over the Semmering, and the first carrying a passenger. While testing the engine the next day, the carburetor caught fire, destroying the top wing in the process.
  The LA purchased the Type C prototype (AD 353) on 10 September 1913 under the military designation C-01. Before committing the type for production, C-01 was flight tested in concert with a second prototype, designated C-02 (see Lohner 10.13). In February 1914 C-01 was stationed at Flugpark 3 in Gorz. The designation was changed to 10.12 in February 1915.


Lohner 10.13

  Lohner built a second Gebirgsflieger Type C prototype (AD 406) for factory flight test and evaluation. The completion date was prior to 10 September 1913. In view of the imminent delivery of Type C production machines, Uzelac requested the purchase of this company-owned aircraft for use as a transition trainer. Designated C-02, the Pfeilflieger was turned over to the LA on 13 December 1913 and formally purchased on 29 January 1914. Lohner C-02 was stationed at Flugpark 1 in February 1914 and redesignated 10.13 in February 1915. It was last reported based at Flek 7 in May 1915.


Lohner B.II Series 12

  For operation in mountainous terrain, the LA ordered the Type C Gebirgsflieger (mountain flyer), a lighter Type B that was powered by the new 85 hp Hiero four-cylinder engine which weighed 51 kg (112 lb) less than the six-cylinder, 90 hp Daimler. The Type C was a new design featuring a vertical fuselage sternpost as compared to the Type B's horizontal sternpost. To serve as an engine and structural-test machine, Cyklon (AC 957 - a lightened Type B) was purchased on 27 November 1912 and delivered to the LA in December. After Cyklon failed the load test, chief engineer Paulal blamed "the less-robust construction and worn airframe" and assured the LA that the production Type C would have a safety factor of at least 5 (3.5 was specified) which may explain why a production airframe was not subjected to load tests.
  The Type C prototype, designated C-01 (later 10.12), was delivered to the LA in August 1913. The second prototype remained the property of Lohner until purchased by the LA as C-02 (10.13) in January 1914. On 10 December 1913, the LA ordered 24 Type C Gebirgsflieger which were designated C-1 to C-24 (AD 500-523). Another Gebirgsflieger, designated C-25 and given a reinforced engine mount and longer fuselage, was delivered in July 1914. As their first production order, UFAG received a contract for 18 Type C, designated C-41 to C-58, on 9 January 1914.
  The first production aircraft, designated C-1, was accepted on 4 February 1914 and five machines followed in short order. Lohner flight testing was performed by company pilots Viktor Wittmann, Edmund Sparmann and Ferdinand Konschel with Lili Steinschneider, the first Hungarian woman pilot, often in the observer's seat. After a demonstration by Karl Illner, Uzelac who positively enjoyed flying new aircraft, took the Type C aloft. He reported vibrations of such intensity that his hands were "electrified," forcing him to wrap his arms around the wheel to maintain control. Being flown without a passenger, the aircraft was extremely nose heavy and only by pulling the control column hard against his chest was Uzelac able to land safely. Lohner blamed the vibrations on the Hiero engine, but Uzelac said such vibrations were absent from the Hiero-engined Etrich Taubes. On the plus side, the Type C with a passenger aboard showed good performance and flight characteristics.
  Oberleutnant Eugen Elsner, an experienced pilot assigned to the Versuchsflik (test section) and responsible for aircraft acceptance, was one of the officers who performed the customary "sign-off" flight. In reply to Elsner's inquiry whether tight turns and dives were safe, Paulal avowed that "there was absolutely nothing to fear." On 9 March 1914, a black day for the LA, Elsner and his passenger, Zugsfuhrer Philipp Srna, were killed when the left wing of aircraft C-2 collapsed in flight. Eye witnesses reported that the accident occurred in level flight, but Lohner claimed that Elsner was pulling out of a "full-throttle dive." All Type C aircraft were grounded, Lohner and UFAG production stopped, and an order for an additional 18 aircraft deferred pending the outcome of the crash committee findings.
  When airframe C-5 was tested on 14 March 1914, the wings failed much like Elsner's crash at a load factor of 2.4. Lohner then reinforced the wing cellule but it was not enough. On the third test, performed 20 March 1914, a new wing with heavier fittings, stronger struts, and additional wire bracing achieved satisfactory results. It was recommended that the existing wings be reinforced in the same manner, but the LA countermanded the crash commission on grounds that the profusion of additional wire rigging would make it difficult, if not impossible, to properly align the wings. Nor would the resulting performance meet the contractual specifications. In April 1914, the LA ordered Lohner to deliver new wings at the company's expense, but later provided funds to speed replacement in view of the deteriorating political situation. Professor Richard Knoller designed the new Type C wing employing a stronger spar and thicker rib section that "Paulal had so steadfastly refused to consider in the past."
  At the time of mobilization the Type C aircraft were grounded, but notwithstanding their poor condition six aircraft were provisionally reinforced and ready for assignment on 1 August 1914. Lohner was scheduled to complete the remaining modification by 31 October 1914. The Type C served with Fliks 4 and 6 in the Balkans and Fliks 8, 10, and 15 on the Russian Front. The first reports from the Front were hardly encouraging. On 25 August 1914, the commander of Flik 10 reported:
  The squadron's six aircraft have such strong vibrations induced by the unbalanced Hiero engine that in spite of great care taken during flight and landing, rigging wires snap and metal fittings, fuel and water lines break. Because of the vibrations, the instruments are unreadable.
  On the other hand, five Type C biplanes were flown by Flik 6 at Igalo from October-December 1914 with moderate success. Armed with an observer's machine gun mounted on the port side, Lohner C-11 supported infantry attacks at Grab (9 November 1914) and Trebinje (28 December 1914), thought to be among, if not the first, "infantry contact patrols" of the war. Another first occurred on 30 November 1914, when Oberleutnants Bela Losonczy von Losoncz and Johann Wierzejski of Flik 15, flying a Lohner Type C Pfeilflieger, shot down a Russian aircraft with a repeating rifle. At the Front, the Type C was flown only because no other aircraft were available, and it was quickly withdrawn as soon as German replacement aircraft arrived.
  In February 1915, the Type C was re-designated Lohner B.II 12.01 to 12.25 (ex C-1 to C-25). The Type C was withdrawn from the Front in May 1915 and seven dispatched to Fischamend for installation of new wings and other modifications. From early 1916 through March 1917, the Flugzeugwerk Fischamend built 45 Type C trainers, designated Lohner B.II (Fd) series 74. In June 1917, the last original Lohner B.II (12.17) was retired from service and placed into the aircraft collection at Fischamend.
Lohner B.II Series 12 Specifications
Engine: 85 hp Hiero
Wing: Span Upper 13.00 m (42.65 ft)
Span Lower 9.20 tn (30.18 ft)
Chord Upper 1.50 m (4.92 ft)
Chord Lower 1.49 m (4.89 ft)
Gap 1.85 m (6.07 ft)
Stagger 0.95 m (3.12 ft)
Total Wing Area 30.4 sq m (327 sq ft)
General: Length 8.30 m (27.23 ft)
Height 3.20 m (10.50 ft)
Empty Weight 560 kg (1235 lb)
Loaded Weight 920 kg (2029 lb)
Maximum Speed: 125 km/hr (78 mph)
Climb: 1000m (3,281 ft) in 7 min


Lohner B.III Series 14

  To restore confidence in Lohner aircraft after the Pfeilflieger wing failures, Professor Knoller was chosen to redesign the wing structure. First appearing in the Lohner Type E, Knoller's design had fewer wing ribs, a thicker rib section, reduced wire bracing, and wing tips supported by V-struts. The Knoller wing, approved by the LA in November 1914, was specified for 24 Type E Pfeilfliegers, of which 16 were ordered from Lohner and 8 from UFAG. The aircraft built by Lohner (AD 813-828), initially numbered E-1 to E-16, were re-designated B.III 14.01 to 14.16 in February 1915. The UFAG-built aircraft were numbered E-20 to E-27; then changed to E-51 to E-58 before being re-designated B.III (U) 14.51 to 14.58. When the contract was signed on 4 January 1915, Type E assembly was already underway. Deliveries were scheduled to end in early February; however, most of the aircraft were not accepted until April 1915.
  The Type E was issued singly to Fliks 2 (Serbian Front), 12 (Isonzo Front), and 16 (Karnten). Fitted with a 100 hp Daimler engine, the aircraft were reported so badly underpowered as to be virtually useless. Soon after the start of hostilities with Italy, Army Group Rohr wrote:
  Flik 12 is equipped with Type E Pfeilfliegers that are unable to carry machine gun or bomb armament. Owing to the poor rate of climb and radius of action, the aircraft are barely equal to the difficult mountainous terrain (Karnten region). To direct the heavy artillery, we urgently request aircraft with more powerful engines.
  As a result, many of the B.III series 14 aircraft were dispatched directly from the factory to training units (Fleks 1-5 and 7) and were soon joined by those from the Front. By October 1915, five B.IIIs remained in training inventory, and plans to modify these for dual controls were dropped. As late as July 1917, four B.III trainers were still active.

Lohner B.III Series 14 Specifications
Engine: 100 hp Daimler
Wing: Span Upper 13.60 m (44.62 ft)
Span Lower 9.14 m (29.99 ft)
Chord Upper 1.65 m (5.41 ft)
Chord Lower 1.55 m (5.09 ft)
Sweepback Upper 12 deg
Gap 1.90 m (6.23 ft)
Stagger 0.71 m (2.33 ft)
Total Wing Area 31.9 sqm (343 sq ft)
General: Length 8.43 m (27.66 ft)
Height 3.15 m (10.33 ft)
Empty Weight 685 kg (1510 lb)
Loaded Weight 1000 kg (2205 lb)
Maximum Speed: 115km/hr(71 mph|
Climb: 1000m (3,281 ft) in 11 min 20 sec


Lohner B.IV Series 15

  In May 1915, under the direction of Major von Umlauff Lohner rebuilt the Lohner 10.03 (Type E) prototype with new wings, a simplified undercarriage, and a 100 hp Mercedes engine. The rebuilt Pfeilflieger was designated Type G and upon delivery on 21 June 1915, received the military designation B.IV 15.01. It was the sole Type G built by Lohner, although UFAG delivered a batch of eight aircraft designated B.IV(U) series 15.5. Aircraft 15.01 was written-off in August 1915.

Lohner B.IV Series 15 Specifications
Engine: 100 hp Mercedes
Wing: Span Upper 13.60 m (44.62 ft)
Span Lower 9.10 m (29.86 ft)
Total Wing Area 31.9 sq m (343 sq ft)
General: Length 8.43 m (27.66 ft)
Empty Weight 725 kg (1599 lb)
Loaded Weight 1000 kg (2205 lb)
Maximum Speed: 115 km/hr(71 mph)
Climb: 1000m (3,281 ft) in 11 min


Lohner B.II(U) Series 12.4

  The first production contract UFAG received, signed on 9 January 1914, called for 18 Lohner Type C biplanes powered by the 85 hp Hiero engine. The original aircraft designation, C 41 to C 58, was changed to Lohner B.II(U) 12.41 to 12.58 in February 1915. The UFAG factory began production on 1 March 1914 and the first aircraft were rolled out in early June, only to be returned for "reconstruction" because serious structural deficiencies had been discovered in the Lohner-built Type C biplanes. Acceptance of the strengthened Type C began in August and ended in November 1914. The UFAG-built B.II was assigned to Fliks 4, 8, 9, 15 and 16. The most notable accomplishment occurred when six aircraft of Flik 9, carrying bombs in place of the observers, attacked the Serbian arsenal at Kragujevac on 24 November 1914. Flik 9 reported the undercarriages were so fragile that most of the aircraft suffered structural damage. Beginning in May 1915, the remaining biplanes were sent to Fleks 1-5 and 7 to serve as trainers until 15 November 1915, at which time those damaged aircraft requiring extensive repairs were to be written-off. However, a few UFAG-built B.II biplanes remained in training inventory until May 1916.


Lohner B.III(U) Series 14.5

  UFAG signed a production contract on 18 January 1915 for eight Lohner Type E biplanes powered by the 100 hp Daimler engine. As assembly work was already underway, the aircraft were scheduled for delivery between 1 and 25 February 1915. To avoid conflict with Lohner, the designation numbers E-20 to E-27 were changed to E-51 to E-58 and remained in force until February 1915, when the aircraft were redesignated Lohner B.III(U) 14.51 to 14.58. The biplanes, accepted during April-May 1915, served with Fleks 1, 2, 3, 5, 7, and 9 as trainers. Aircraft 14.58 was attached to Flik 16 as a trainer on the Italian Front in May-June 1916. Two aircraft remained active as secondary school machines until 1918.


Lohner B.IV(U) Series 15.5

  On 15 May 1915, UFAG received an order for eight Lohner B.IV(U) biplanes, numbered 15.51 to 15.58 and based on the Lohner Type G prototype (15.01). The airframe was identical to the Lohner B.III(U) series 14.5 except that a 100 hp Mercedes engine and a new undercarriage were fitted. Of the eight aircraft, accepted between May and July 1915, four were intended for Flik 12 on the Isonzo Front but they saw little operational service because of their poor performance. In mid-1916 all eight biplanes were attached to Fleks 1-5 and 7 and as of July 1917, three B.IV(U) series 15.5 trainers were still in service.


Lohner B.II(Fd) Series 74

  The rationale for building a patently obsolete pre-war aircraft when modern trainers were available appears hardly justifiable, even if the design was stable and easy to fly. Yet in early 1916, the Flugzeugwerk began production of 46 new Lohner B.II(Fd) series 74 trainers, the last of which was delivered in March 1917! Another seven were modified from original Lohner-built airframes. The series that numbered 74.01 to 74.53 was powered by a 85 hp Hiero engine. In the course of its training duties, the B.II(Fd) was often repaired and modified. It was flown as an advanced trainer at Fleks 1-7, 12, and 13 and Schulkompagnie 1. Forty-five B.II(Fd) biplanes were in the training command inventory as of 1 July 1917, and at least 15 were still active in mid-1918.

Lohner B.II(Fd) Series 74
Engine: 85 hp Hiero
Wing: Span Upper 13.50 m (44.29 ft)
Sweepback Upper 13 deg
Gap 1.80 m (5.91 ft)
Total Wing Area 32.0 sq m (344 sq ft)
General: Length 8.30 m (27.23 ft)
Track 1.90 m (6.23 ft)
Empty Weight 530 kg (1169 lb)
Loaded Weight 776 kg (1711 lb)
Climb: 1000m (3,281 ft) in 8 min 10 sec

Lohner-Etrich AD 354

  On 14 June 1913, Lohner-MLG entered two Lohner-Etrich Renn Gebirgs monoplanes (racer mountain type - works number AD 127 and AD 354, powered by an 85 hp Hiero engine) in the Second International Flugmeeting at Aspern, assigned to pilot Gianni Widmer and both carrying the competition number 26. When the radiator hose on AD 127 ruptured, Widmer, although badly scalded, quickly switched to the second monoplane (AD 354), but he failed to place in the top ten finishers. In early 1914, Etrich “No.58" was purchased by the LA and given the designation Versuchs Gebirgs Etrich E-1 (experimental mountain type). From available photographs, it appears that AD 354 and Etrich E-1 (No.58) are the same aircraft. Etrich E-1 was under repair at Flugpark 3 in Gorz during January-February 1915, but appears to have been written off and consequently not listed in the February 1915 LA directive for re-numbering aircraft.

Lohner-Etrich (AD 354) Specifications
Engine: 85 hp Hiero
Wing: Span 14.40 m (47.24 ft)
Chord 2.60 m (8.53 ft)
Total Wing Area 28.0 sq m (301 sq ft)
General: Length 9.00 m (29.53 ft)
Height 3.00 m (9.84 ft)
Empty Weight 605 kg (1334 lb)
Maximum Speed: 80 km/hr (50 mph)
Climb: 300m (1,000 ft) in 10 min


Lohner 10.15

  The Schichtpreis Eindecker Type 1914 (AD 489) was the last aircraft built by Lohner to incorporate Taube wing-warping controls. Construction was begun in October 1913 and completed on 29 December 1913. On 4 February 1914, Lohner offered the monoplane, powered by a 80 hp Gnome rotary engine, to the LA for testing and would supply new wings if desired, but the LA was not interested.
  AD 489 was one of the two aircraft entered by Lohner pilot Viktor Wittmann in the Schicht Flug but he chose to fly Pfeilflieger AD 553 (10.16). In June 1914, AD 489 was flown by Gianni Widmer (competition No.23) in the Third International Flugmeeting, but he failed to win any prizes. Requisitioned at the start of the war, AD 489 was sold to the LA in October 1914 and designated Gnome-Etrich or Lohner A 23. It became Lohner 10.15 in April 1915. In its long training career, the monoplane served with Fleks 1 and 8 and was still active with Flek 6 as late as November 1917.

Lohner 10.15 Specifications
Engine: 80 hp Gnome
Wing:
Span 11.60 m (38.06 ft)
Total Wing Area 32.0 sq m (344 sq ft)
General:
Length 7.70 m (25.26 ft)
Height 2.50 m (8.20 ft)
Empty Weight 278 kg (613 lb)
Loaded Weight 658 kg (1451 lb)
Maximum Speed: 130 km/hr (81 mph)
Climb: 1000m (3,281 ft) in 9 min

Lohner 10.17

  Before embarking on the production of 24 Lohner B.VII (Type J) Pfeilfliegers, the LA ordered one prototype, designated J-01 (AE 201) and powered by a 150 hp Daimler engine, for test and evaluation. When the contract was signed on 17 January 1915, the J-01, later designated 10.17, was nearing completion. It was delivered on 5 March 1915 and performed its maiden flight on 18 March with Fahnrich Edmund Sparmann at the controls. Some minor control problems resulting from the airfoil-shaped tailplane were reported, but these would be corrected on the production machines. In comparison trials supervised by Flars engineer Richard von Mises, the 10.17 prototype, powered by the improved 160 hp Daimler engine, reached 2000 meters (6562 ft) in 17 minutes as compared to 26 minutes with the original 150 hp engine. Because of protracted engine problems, the 10.17 was not accepted until 14 August 1915. It was assigned to Flik 17, one of the first squadrons to receive the Lohner B.VII series 17 production aircraft. During frontline trials the 10.17 reached an altitude of 3500 meters (11,482 ft) in September 1915, and flew several operational missions. The 10.17 was sent to the factory in March 1916 for repairs which were completed in May. It is on record that 10.17 served with Flik 16 through October 1916.


Lohner 10.28

  To evaluate the experimental 150 hp Praga V-12 engine the LA ordered one Lohner Type Js prototype, 10.28 (AE 310), on 29 October 1915, from a projected batch of three aircraft (AE 310-312). The air-cooled Praga V-8 and V-12 engines proved extremely unreliable and only sporadic flight tests were performed. Karl Kriger's flight log recorded one (maiden?) flight of the 10.28 at Aspern in March 1916. After Flars prepared the installation drawings in January 1917, Lohner fitted a 150 hp (or 120 hp) Daimler engine and the re-engined 10.28 was accepted by Flars on 1 March 1917. The 10.28 was under repair in September 1917, written-off in October and stored at the Aspern depot in March 1918.


Lohner B.V Series 16

  Since the Rapp Motoren Werke of Munich were represented in Austria-Hungary by the Motor-Luftfahrzeug-Gesellschaft (in which Lohner had an interest), it was to be expected that an aircraft powered by a Rapp engine would be proposed to the LA. The result was that Lohner received a contract on 17 January 1915 for 24 Type H Pfeilfliegers powered by the 140 hp Rapp V-8 engine. Recurring engine problems - primarily carburetor fires, excessive oil consumption and endless mechanical modifications - delayed the first Type H acceptance until April 1916, a year later than scheduled. In the event, the LFT cancelled the order after accepting only six machines because the Type H was too heavy to meet the performance specifications. These were designated Lohner B.V series 16.01 to 16.06 (AE101-106). Plagued by recurrent carburetor fires in training service with Fleks 3, 4, 8, 9, and 14, the dangerous B.V aircraft were grounded and placed in storage to await further developments, (see Lohner B.VI series 16.1)

Lohner B.IV Series 16 Specifications
Engine: 140 hp Rapp
Wing: Span Upper 14.40 m (47.24 ft)
Span Lower 10.00 m (32.81 ft)
Chord Upper 1.85 m (6.07 ft)
Chord Lower 1.70 m (5.58 ft)
Sweepback Upper 13 deg
Gap 2.10 m (6.89 ft)
Stagger 0.69 m (2.26 ft)
Total Wing Area 38.5 sq m (414 sq ft)
General: Length 8.70 m (28.54 ft)
Height 3.25 m (10.66 ft)
Track 2.05 m (6.73 ft)
Empty Weight 840 kg (1852 lb)
Loaded Weight 1225 kg (2701 lb)
Maximum Speed: 122 km/hr (76 mph)
Climb: 1000m (3,281 ft) in 11 min 5 sec


Lohner B.VI Series 16.1

  After the Lohner B.V failure, the LFT required Lohner to redesign the remaining 18 aircraft on order to meet the performance specifications. Known as the Type H2, the airframe was lightened throughout and fitted with a shorter, plywood-covered fuselage replacing the fabric-covered one of the B.V. The wing cellule had a reduced span, sweepback and stagger. These new aircraft were designated Lohner B.VI series 16.11 to 16.28 (AE 107-124). Delivered after a year's delay, the Rapp-engined B.V and B.VI biplanes were assigned directly to training units. In June 1916, the training command was forced to ground all of them because of recurrent carburetor fires. After corrective measures, limited flying was resumed at Fleks 2-6, 8, 9, and 14. In the fall of 1917, the remaining aircraft (17 or 18) were assigned to Flugpark 1 and sporadically flown until June 1918, when a fatal crash attributed to an engine fire caused the B.V and B.VI biplanes to be withdrawn from service altogether. Several were used as non-flying instructional airframes at the officer flying school in Wiener-Neustadt through 1918. According to one report, aircraft 16.01 was fitted with the experimental Praga engine in August 1916 for flight testing.
  
Lohner B.VI Series 16.1 Specifications
Engine: 140 hp Rapp
Wing: Span Upper 12.80 m (41.99 ft)
Span Lower 11.40 m |37.40 ft)
Chord Upper 1.78m (5.84 ft)
Chord Lower 1.78 m (5.84 ft)
Sweepback Upper 6 deg
Gap 1.90 m (6.23 ft)
Stagger 0.39 m (1.28 ft)
Total Wing Area 38.45 sq m (414 sq ft)
General: Length 7.60 m (24.93 ft)
Height 3.00 m (9.84 ft)
Track 2.05 m (6.74 ft)
Empty Weight 802 kg (1768 lb)
Loaded Weight 1205 kg (2657 lb)
Climb: 1000m (3,281 ft) in 10 min 15 sec


  
Lohner B.VII Series 17

  The last and most-successful Pfeilflieger design was the Lohner B.VII (Type J), built in greater number than any other Lohner landplane. Conceived as a load-carrying aircraft (Lastflugzeug), the Type J was a development of the Type D series 13 but fitted with the more powerful 150 hp Daimler engine. On 17 January 1915, the LA gave Lohner a contract for one prototype (10.17) and 24 Type J production aircraft designated B.VII 17.01 to 17.24 (AE 202-225). An additional 24 B.VII (U) Pfeilfliegers were ordered from UFAG in March. Lohner deliveries were scheduled to commence in April 1915 and continue at a rate of four aircraft per week, but the first machine was not accepted until August 1915. The fabric-covered fuselage was fitted with the favored common cockpit that provided staggered seating for the pilot and observer. Armament consisted of hand-held weapons until early 1916, when some aircraft were retro-fitted with a single machine gun mounted on a simple pivot fixture. With an observer aboard, the bomb load was about 80 kg (176 lb). A maximum bomb load of 220 kg (485 lb) could be carried in lieu of the observer, but there is no record of aircraft operated in this configuration.
  The B.VII began to reach squadron service in August 1915, replacing the Lloyd C.I and C.II biplanes stationed in mountainous terrain. The B.VII series 17 Pfeilfliegers were assigned to Fliks 6, 9, and 15 in the Balkans and to Fliks 7, 16, and 17 in South Tirol and Karnten. Judging by early combat reports, Lohner had designed a rugged machine that was highly regarded for its load-carrying ability and performance. Years later, Julius Arigi remembered the Lohner B.VII as being "the first series aircraft that was totally effective in high mountains and, most importantly, an aircraft that we, as pilots, fully trusted." Between August 1915 and mid-1916, the B.VII series 17 performed numerous long-range reconnaissance and bombing raids, some of five or six hours duration. However, the reliability of the 150 hp Daimler engine left much to be desired. After the outspoken commander of Flik 16, Hauptmann Raoul Stojsavljevic, voiced his displeasure during a visit to Vienna in November 1915, his squadron was the first to receive the more powerful Lohner B.VII series 17.3 in December 1915.


Lohner B.VII Series 17.3

  The B.VII series 17.3 was powered by the improved 160 hp Daimler engine that had been test flown in the Lohner 10.17 and was just coming into production. Sixteen B.VII series 17.3 biplanes, numbered 17.31 to 17.46 (AE 808-823), were ordered and although the contract was not signed until 20 March 1916, acceptances had already begun in December 1915 and ended in March 1916, only one month behind schedule. The B.VII series 17.3 began to arrive at the Front in December 1915 and served with Fliks 7, 8, 16, and 17 and singly with Fliks 12 and 19 on the Isonzo Front.
  The B.VII's range and bomb load presented the LFT with the opportunity to attack targets deep in Italian territory. Among the most notable was the bombing raid against the Milan electro-generating works undertaken on 14 February 1916. While older Lohner B.VII and Lloyd C.II machines performed a diversionary raid on Schio, twelve B.VII series 17.3 would attack the prime target. Aircrews of Fliks 7, 17, and 16, based at Gardolo and Pergine, prepared for a round trip of about 380 km (236 miles) over imposing mountainous terrain that presented a formidable obstacle. Hauptmann Eugen von Steinner-Goltl, commander of Flik 17, recalled:
  We took off with 270 liters fuel and 80 kg bombs and assembled at 1600 meters in the dawning light. My Gral II took the lead, steering a straight compass course so we would quickly reach Milano without undue fuel consumption. At 3000 meters we crossed the enemy lines some 700 meters below us. We were met by murderous artillery fire. After our compass froze, we navigated by the distinctive lakes and valleys. On the way the squadron dispersed entirely. After one and a half hours, the Lombard plain greeted us. My heart laughed, so much flatland - so many landing possibilities. Finally my observer picked out Milan in the haze.
  Gral II only just got home. Spending almost five hours in the air "we landed with a stalled engine; inspection showed a broken crankshaft." Given the conditions, it is remarkable that the target was hit at all and that no aircraft were lost. Of the 12 aircraft that took off from Pergine, nine reached Milano and damaged the Porta Volta power station, one bombed Monza by mistake and two made forced landings in friendly territory. Of the few B.VII that carried a machine gun, one succeeded in shooting down an Italian aircraft. Other attacks under similar circumstances were undertaken in 1916. Flik 7 lost two B.VII (17.40 and 17.41) behind the Italian lines during a squadron attack on the Piave bridges on 27 March 1916. In the course of an attack on Udine, aircraft 17.42 became Baracca's second victory on 16 May 1916. Only two B.VII aircraft served on the Russian Front, one when Flik 7 was transferred to Galicia and one with Flik 26.

Lohner B.VII Series 17.3 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 15.40 m 150.52 ft}
Span Lower 11.20 m (36.74 ft)
Chord Upper 2.00 m (6.56 ft)
Chord Lower 1.83 m (6.00 ft)
Sweepback Upper 13 deg
Gap 2.21 m (7.25 ft)
Stagger 0.352 m (1.15 ft)
Total Wing Area 44.0 sq m (473 sq ft)
General: Length 9.50 m (31.17 ft)
Height 3.75 m (12.30 ft)
Track 2.22 m (7.28 ft)
Empty Weight 990 kg (2183 lb)
Loaded Weight 1441 kg (3177 lb)
Maximum Speed: 121 km/hr (75 mph)
Climb: 1000m (3,281 ft) in 7 min 41 sec


Lohner B.VII(U) Series 17.5

  Following the successful tests of the Lohner B.VII prototype (10.17), UFAG was given a contract to build 48 Lohner B.VII(U) biplanes on 30 March 1915. Deliveries were scheduled to start on 30 April and end on 2 July 1915. In March 1915, the contract was reduced to 24 aircraft in favor of the Brandenburg G.I(U) series bomber. After four aircraft were accepted, production was stopped in August 1915 to repair unacceptable welds, for which UFAG was penalized. The last of 24 Lohner B.VII(U) biplanes, numbered 17.51 to 17.74 and powered by 150 hp Daimler (MAG) engines, was delivered in January 1916. Because of the unreliable MAG-built engines, the aircraft were declared unfit for frontline service. Beginning in November 1915, the UFAG-built B.VII biplanes were flown as secondary trainers with Fliks 2 and 19 as well as Fleks 2-6, 8, and 9 and Schulkompagnie 1 and 2. Five were still in use as trainers when the war ended.


Lohner B.VII Series 17.8

  Nine older B.VII series 17 machines (known are 17.01-05, 09, 12, and 20) were rebuilt by Lohner to take the 160 hp Daimler engine. Fitted with a new motor mount and fuselage frames and a machine gun ring for the observer, the modified aircraft were designated Lohner B.VII series 17.8, numbered 17.81 to 17.89. These aircraft arrived at the Front in February-March 1916. They were assigned to Fliks 12 and 23 on the Isonzo Front and Fliks 7, 8, and 17 in the Tirol.
  With the appearance of the Brandenburg C.I, the B.VII aircraft were withdrawn and assigned to Fleks 3-5, 7-9, and 13 for advanced pilot training. As of July 1917, thirty-seven B.VII aircraft were listed in LFT inventory and by October 1918, this number had been reduced to eight damaged B.VII aircraft stored at Flep 2.

Lohner B.VII Series 17.8 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 15.40 m (50.52 ft)
Span Lower 11.20 m (36.74 ft)
Chord Upper 2.00 m (6.56 ft)
Chord Lower 1.83 m (6.00 ft)
Sweepback Upper 13 deg
Gap 2.21 m (7.25 ft)
Stagger 0.35 m (1.15 ft)
Total Wing Area 44.0 sq m (473 sq ft)
General: Length 9.50 m (31.17 ft)
Height 3.75 m (12.30 ft)
Track 2.22 m (7.28 ft)
Empty Weight 941 kg (2075 lb)
Loaded Weight 1392 kg (3069 lb)
Maximum Speed: 124 km/hr (77 mph|
Climb: 1000m (3,281 ft) in 9 min

Lohner D.I Series 111

  Flars approved the development of the Lohner D.I (Type AA) fighter in August 1916 and ordered four prototypes, three biplanes and one triplane. Designed by Leopold Bauer, the first prototype, designated 10.20, made its debut at Aspern on 5 September 1916. Powered by a 160 hp Daimler engine, it was ground tested by Lohner pilot Karl Kriger, who was to receive Kr 2000 for performing the maiden flight. On 26 October Flars warned Lohner not to fly the aircraft unless the following problems were corrected: the taxiing stability was poor, the control surfaces were too small, the undercarriage lacked shock cords, and the poor visibility made ground maneuvers hazardous. It was returned to the factory for modification on 31 October.
  The 10.20 re-appeared at Aspern on 17 November with a lengthened fuselage. Taxi trials, beginning on 23 November, showed insufficient rudder area but an enlarged rudder tested on 17 December failed to improve ground control. After a tail fin and larger rudder were installed, the rudder response was judged satisfactory and on 29 December 1916, Kriger performed a short hop, believed to be the maiden flight. Upon landing several wing ribs broke. New wings were fitted on 31 December 1916. Flars, contending that the modified prototype "had no future," withheld additional funds but testing of the D.I prototype continued although there was no hope of production. Between 6 January and 28 January 1917, Kriger performed a series of test flights that, despite a severe tail-heavy condition, demonstrated satisfactory performance. Attempts to correct the tail-heaviness were moderately successful, but on 14 February, the 10.20 was damaged in a forced landing and returned to the factory for modification.
  When the much-altered 10.20, now designated 10.20A (later D.I 111.01) returned to Aspern on 3 March 1917, it was fitted with twin-strutted wings. Kriger performed the maiden flight on 4 March with satisfactory results. After a series of test flights in April, some with Oberleutnant Oskar Fekete at the controls, the 10.20A (111.01) was accepted by Flars on 29 April 1917. Sporadic trials continued until 6 June 1917, when the prototype was demolished by Oberleutnant Ludwig Hautzmayer, who was lucky to escape with his life. Kriger had warned that the 10.20A required a highly-skilled pilot.
  Meanwhile, Lohner had completed the second Type AA prototype, designated 10.20B (later D.I 111.02). Virtually a new design, a raised fin running from cockpit to tail now graced the fuselage, and a more powerful 185 hp Daimler engine was installed. The I-strutted wing cellule was braced to the fuselage by a pair of V-struts, which eliminated the need for interplane wires. Kriger, who performed the maiden flight on 2 June 1917 at Aspern, reported a "fair amount of nose-heaviness." Flight testing continued in June-July. On 2 August, the 10.20B was accepted by Flars, and Lohner pilot Kriger continued flight testing the fighter through October 1917. The 10.20B (111.02) was based at Aspern in February 1918, and last reported at Flugpark 1 in March 1918.
  Following close on the heels of the 10.20B, the third Type AA prototype, D.I 111.03 (a prototype number was not assigned), was assembled at Aspern on 25 June 1917. Of conventional layout, the 111.03 had a large tail fin, a wire-braced wing cellule, and a 185 hp Daimler engine supplied the power. The maiden flight was performed by Kriger on 28 June 1917. A few test flights were recorded through October 1917, when further investigation of the type stopped. The D.I 111.03 was reported at Aspern in February 1918, sent to Flek 6 as an instruction airframe in March, and written-off in August 1918.

Lohner 10.20 (D.I 111.01) Specifications
First Version, I-Strut
Engine: 160 hp Daimler
Wing: Span Upper 6.55 m (21.49 ft)
Span Lower 6.00 m (19.68 ft)
Total Wing Area 16.12 sq m (173 sq ft)
General: Length 4.70 m (15.42 ft)
Height 2.90 m (9.51 ft)

Lohner 10.20A (D.I 111.01) Specifications
Third Version, Twin Struts
Engine: 160 hp Daimler
Wing: Span Upper 7.00 m (22.97 ft)
Span Lower 7.00 m (22.97 ft)
Chord Upper 1.50 m (4.92 ft)
Chord Lower 1.50 m (4.92 ft)
General: Empty Weight 570 kg (1257 lb)
Loaded Weight 826 kg (1821 lb)

Lohner 10.20B (D.I 111.02) Specifications
Engine: 185 hp Daimler
Wing: Span Upper 7.30 m (23.95 ft)
Span Lower 6.70 m (21.98 ft)
Total Wing Area 17.98 sq m (193 sq ft)
General: Length 6.00 m (19.68 ft)
Height 2.95 m (9.68 ft)

Lohner D.I 111.03 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 7.60 m (24.93 ft)
Span Lower 7.60 m (24.93 ft)
Chord Upper 1.50m (4.92 ft)
Total Wing Area 20 sq m (2.15 sq ft)
General: Length 6.35 m (20.83 ft)
Height 3.00 m (9.84 ft)
Empty Weight 623 kg (1374 lb)
Loaded Weight 889 kg (1960 lb)
Maximum Speed: 175 km/hr (109 mph)
Climb: 1000m (3,281 ft) in 2 min 40 sec

Lohner 10.18

  The Lohner 10.18 (Type Jc - AE 778) was the first army aircraft designed by Lohner's new chief engineer, Leopold Bauer. It was created to meet the armed two-seater (military class C) specification issued in late 1915. As might be expected, the 10.18 had little in common with its predecessors. The fuselage was plywood-covered, the wing cellule simplified, and the sweepback greatly reduced. Extant records show that the 10.18, powered by a 185 hp Daimler engine, was assembled at Aspern on 4 January 1916, ready for flight on 20 January, and test pilot Karl Kriger performed the maiden flight on 5 February 1916.
  Having completed tests as the prototype for the Lohner C.I series 18 production aircraft, the 10.18 temporarily was fitted with a 140 hp Rapp V-8 engine to evaluate the engine for use in the Lohner B.VI series 16.1 biplane. In August 1916, the 10.18, once again powered by a 185 hp Daimler engine, was assigned to the aircraft test group at Aspern for training and experimental purposes.


Lohner C.I Series 18

  With the conclusion of the Lohner 10.18 evaluation trials, Lohner signed a contract on 10 March 1916 for 24 C.I biplanes (Type Jc) powered by a 160 hp Daimler engine. Parts manufacture had begun in December 1915 and delivery was scheduled to start on 5 April and end in July 1916. Flars stopped delivery in June 1916 because, compared with the Brandenburg C.I, the first production machines demonstrated "hopelessly inadequate" performance even after the contractual flight specifications had been lowered. Lohner, unable to rectify the shortcomings, was obliged to pay a penalty. After a long delay, Flars accepted a total of 23 C.I biplanes numbered 18.01 to 18.23.71 Unsuitable for frontline service, the C.I machines were used as trainers by Fleks 1, 4-9, 11, and 14 and Schulkompagnie 2. In November 1917, nine damaged aircraft were dispatched to Flugpark 1 for disposal, but a few remained in training service until mid-1918.

Lohner C.I Series 18 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 12.80 m (41.99 ft)
Span Lower 12.10 m (39.70 ft)
Chord Upper 1.78 m (5.84 ft)
Chord Lower 1.78 m (5.84 ft)
Sweepback Upper 8.5 deg
Gap 1.90 m (6.23 ft)
Stagger 0.26 m (0.85 ft)
Total Wing Area 38.45 sq m (414 sq ft)
General: Length 9.25 m (30.35 ft)
Height 3.30 m (10.83 ft)
Track 2.05 m (6.73 ft)
Empty Weight 869 kg (1916 lb)
Loaded Weight 1333 kg (2939 lb)
Maximum Speed: 132 km/hr (82 mph)
Climb: 1000m (3,281 ft) in 7 min 56 sec



Lohner C.I Series 18.5

  On 22 September 1916, a contract was signed for 17 improved Lohner C.I biplanes (Type Jcr) numbered 18.51 to 18.67. Flight evaluation was performed with aircraft 18.24 that was modified to Type Jcr standard and reportedly renumbered 18.51. The Type Jcr, powered by a 160 hp Daimler engine, was fitted with a new wing cellule and lightened throughout, resulting in improved but still mediocre performance. The series 18.5 machines were flown as trainers by Fleks 3, 5, 7, 9, 12, and 13. In March 1917, aircraft 18.61 to 18.64, additionally armed with a Type VK II machine gun canister, were pressed into home-defense duty with the Flars Versuchsflik (test squadron) at Aspern. As of July 1917, thirty- six C.I aircraft were listed on training status, perhaps not all in flying condition.

Lohner C.I Series 18.5 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 12.44 m (40.81 ft)
Chord Upper 1.78 m (5.84 ft)
Chord Lower 1.78 m (5.84 ft)
Sweepback Upper 8.5 deg
Gap 1.90 m (6.23 ft)
Stagger 0.26 m (0.85 ft)
Total Wing Area 43.3 sq m (465 sq ft)
General: Height 3.00 m (9.84 ft)
Empty Weight 759 kg (1674 lb)
Loaded Weight 1216 kg (2681 lb)
Maximum Speed: 134 km/hr (83 mph)
Climb: 1000m (3,281 ft) in 5 min 37 sec
2000m (6,562 ft) in 12 min 45 sec
3000m (9,843 ft) in 22 min 56 sec

Lohner 10.21

  In early 1914, Uzelac asked Lohner to submit specifications for a multi-seat battleplane powered by two 150 hp engines. The LA returned the drawings for additional study on 30 March 1914. One month later, Lohner received funds to design a twin-engined battleplane which featured steering vanes mounted between the outer wing struts to counteract the turning moment and maintain a straight flight in the event one engine failed. The schematic planview was published in Austrian Patent No. 79202 granted on 2 May 1914. The battleplane drawings were re-submitted to the LA on 27 May 1914, but further work was held in abeyance.
  The LA issued new battleplane specifications on 20 August 1914, calling for a speed of 125 km/h (78 mph) and a climb to 1000 meters (3281 ft) in 8 minutes carrying a crew of six. The contract to build one prototype, known as the Lohner Type U (AD 925) and later designated 10.21, was signed on 31 August 1914. The final drawings, dated 9 July 1915, had four crew members; two located in the forward turret, one pilot behind the wings, and one gunner in the rear cockpit. The Lohner 10.21, the first twin-engined aircraft built for the LFT, was reported ready for flight trials in January 1916, but test pilot Karl Kriger's log book reveals that final assembly and ground tests were not completed until 14 April 1916 when he piloted the 10.21 on the maiden flight. During the course of sporadic testing through June 1916, the wing steering vanes and braking wheel were removed. The opposite-rotating 150 hp Daimler engines were replaced by engines revolving in the same direction but performance remained unsatisfactory. The 10.21 was accepted in June 1916 and assigned to Flek 6 in Wiener-Neustadt for further evaluation. Showing little interest, the LFT placed the 10.21 in storage until it was written-off in October 1917. The serial number was reassigned to the single-engined Lohner Type F.

Lohner 10.21 Specifications
Engine: 2 x 150 hp Daimler
Wing: Span Upper 21.00 m (68.90 ft)
Span Lower 16.00 m (52.49 ft)
Chord Upper 2.54 m (8.33 ft)
Chord Lower 2.20 m (7.22 ft)
Total Wing Area 77 sq m (829 sq ft)
General: Length 13.00 m (42.65 ft)
Height 4.20 m (13.78 ft)
Empty Weight 1920 kg (4234 lb)
Loaded Weight 2700 kg (5954 lb)
Maximum Speed: 120 km/hr (74.5 mph)

Lohner C.II Series 112

  Ludwig Lohner and Bauer visited Berlin in February 1916 in an unsuccessful attempt to obtain a Roland C.II manufacturing license from the Luft-Fahrzeug-Gesellschaft. Undaunted, Lohner submitted a derivative project to Flars on 14 April 1916 that was rejected. An improved design submitted by Lohner was supported by Flars, who in August 1916 ordered the first of four prototypes. The first airframe, designated 10.19 (Type AB), was inspected on 1 March 1917 by Flars engineers who criticized the poor forward visibility even though Bauer had positioned the 185 hp Daimler engine low in the fuselage. In addition to some minor changes, Flars demanded that the fuselage frames be relocated to increase the observer's space and strengthen the machine gun mount. The maiden flight of the 10.19 prototype (later designated C.II 112.01), with Kriger at the controls and Bauer as observer, occurred on 4 April 1917. Testing by Kriger and Flars pilots continued through 7 June 1917, at which time Flars prohibited LFT pilots from flying the 10.19 owing to weak wing struts which "had been miscalculated in the design stage." Furthermore, Kriger now refused to fly the aircraft because of a dangerous tail-heavy condition. It was an indication of stability problems that would hamstring the project for almost a year without being resolved.
  In June, the C.II 112.01 (10.19) was sent to Lohner for modification and returned to Aspern in July 1917 with wings of increased area moved aft to alleviate the tail-heaviness. Between 2 August and 1 December 1917, Kriger made occasional test flights but the 112.01 continued to demonstrate unacceptable stability and inadequate climb. Testing was stopped and the prototype placed into storage.
  During June 1917, the remaining three C.II production prototypes were tested in short order. Aircraft 112.03 was assembled at Aspern on 16 June and first flown on 20 June. Kriger reported a severe nose-heavy condition. Only a few flights were performed at Aspern in July after which the 112.03 was dismantled and placed into storage in August.
  Aircraft C.II 112.04 was assembled at Aspern on 18 June 1917 and flown for the first time on 21 June. Like the other C.II prototypes, it demonstrated severe stability problems. After Kriger logged several flights in September 1917, the 112.04 was dismantled and placed into storage.
  Aircraft 112.02, the last to be flown, was assembled at Aspern on 18 June and Kriger performed the maiden flight on 29 June 1917. The 112.02 airframe was static load tested in August but failed to meet the required load factor of 5. Aircraft 112.02 was dismantled and stored at the Lohner factory where it was reported in May 1918. In October 1918, the government purchased the four C.II biplanes, paying only three-quarters of the contracted price because the performance requirements had not been met.

Lohner 10.19 (C.II 112.01) Specifications
Engine: 185 hp Daimler
Wing: Span Upper 9.30 m (30.51 ft)
Span Lower 8.40 m (27.56 ft)
Chord Upper 1.60 m (5.25 ft)
Chord Lower 1.60 m (5.25 ft)
Total Wing Area 30.0 sq m (323 sq ft)
General: Length 7.43 m (24.38 ft)
Height 2.95 m (9.68 ft)
Empty Weight 785 kg (1731 lb)
Loaded Weight 1080 kg (2381 lb)
Maximum Speed: 178 km/hr (110.5 mph)
Climb: 1000m (3,281 ft) in 6 min 35 sec
2000m (6,562 ft) in 14 min 2 sec
3000m (9,843 ft) in 31 min 45 sec

Lohner 10.21 (new) and 10.22

  The Fliegerarsenal (Flars - aviation arsenal) issued specifications in July 1916 for a long-range reconnaissance aircraft and requested Lohner to submit project drawings for two aircraft powered by the experimental 300 hp Daimler V-12 engine and capable of carrying a crew of three, including two observer-machine gunners in the rear cockpit. Lohner proposed the Type F [Fernerkundungs Flugzeug - long-range reconnaissance aircraft). Before much progress was made, the project was cancelled in favor of a 350 hp aircraft designed by Ingenieurleutnant Karl Saliger and Dr Richard von Mises of the Flars construction bureau.
  Structural drawings for the Saliger-Mises design had been completed in September 1916. From the outset Flars had planned to assign the construction to Aviatik, a company with spare manpower, but Aviatik suddenly had its hands full with C.I and D.I aircraft production. Consequently, on 11 December 1916, the LFT command shifted the project to Lohner. The Saliger-Mises specifications called for a top speed of 200 km/h (124 mph) with a rate of climb of 1000 meters (3281 ft) in 4 minutes, a duration of two hours, an armored seat for the pilot, a common cockpit for the crew, one fixed machine gun, and a rear gun located to fire a 180-degree traverse. Parts assembly began in the Lohner shops in January 1917. The first prototype, numbered 10.21 (w/n 33/438), stood assembled at the factory on 24 April 1917. Since the 350 hp engine was not ready, the experimental 300 hp Daimler V-12 engine was installed. The second machine, 10.22 (Type F-w/n 33/439), was completed but not assembled.
  The Lohner flight log shows that the 10.21 was at Aspern ready for flight trials on 2 May 1917. Now began a year-long program, delayed by problems with the new Daimler V-12 engine. From the record it is clear that the 10.21 was used primarily as a test-bed for engine trials. Ground tests were performed on 7 May. During taxi trials on 11 May, the undercarriage shock cords tore apart. On the maiden flight, performed on 12 May, Lohner test pilot Karl Kriger reported severe engine vibrations and tail skid failure. On 16 May, the tailplane broke while taxiing. The "nose and tail heaviness" was reported solved by structural modifications in June 1917. Work was also underway to design a new tail skid and widen the rear cockpit to hold a third crew member. The task of finding a suitable propeller to match the engine-airframe characteristics consumed much of the test program.
  The 10.21 prototype was turned over to the Flars test group on 4 June 1917 and Karl Kriger continued the flight investigation through October 1917, during the course of which the climb rate to 1000 meters (3281 ft) had been lowered from 15 to 3:45 minutes as a result of engine and propeller improvements. On 28 October the engine was removed to install aluminum pistons which, among other modifications, increased the engine rating to 345 horsepower. The 10.21 continued sporadic flights at Aspern to evaluate engine performance up to 4000 meters (13,123 ft) altitude. When last reported in October 1918, the 10.21 prototype was based at Aspern in flying condition.
  In February 1918, preparations were underway to install the experimental 360 hp Daimler six-cylinder engine in 10.22, the second Type F prototype. The 10.22 appeared at Aspern on 14 May 1918 and performed its maiden flight on 27 May. Returned to the factory owing to a minor mishap on 8 June 1918, the 10.22 was last reported at Aspern in August 1918.

Lohner 10.21 Specifications (new)
Engine: 300 hp Daimler
Wing: Span Upper 15.0 m (49.21 ft)
Span Lower 15.0 m (49.21 ft)
Chord Upper 1.96 m (6.43 ft)
Chord Lower 1.96 m (6.43 ft)
Total Wing Area 50.0 sq m (538 sq ft)
General: Length 10.3 m (33.79 ft)
Height 3.50 m (11.48 ft)
Empty Weight 1150 kg (2536 lb)
Loaded Weight 1800 kg (3969 lb)
Maximum Speed: 157 km/hr (97.5 mph)
Climb: 1000m (3,281 ft) in 15 min

Oeffag 50.02

  The Oeffag C.I series 51 production contract stipulated that the 50.02 prototype was to be delivered on 15 June 1915. Oeffag documents record the 50.02 as "completed" in December 1915, an indication that during the course of flight testing extensive modification was required. Dimensionally similar to the 50.01, the 50.02 was fitted with a conventional three-bay wing cellule and powered by a 160 hp Daimler engine. On entering service, the 50.02 was assigned to Flek 6 and Schulkompagnie 1. After repair in 1917, it was assigned to Flek 10. While on an airmail run between Cracow and Lemberg, a carburetor fire caused the 50.02 to crash land and burn at Rzeszow, Galicia on 22 May 1918.

Oeffag 50.02 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 14.58 m (47.83 ft)
Span Lower 13.90 m (45.60 ft)
Chord Upper 2.30 m (7.55 ft)
Chord Lower 2.00 m (6.56 ft)
Dihedral Upper 2 deg
Dihedral Lower 2 deg
Sweepback Upper 9 deg
Sweepback Lower 9 deg
Gap 1.92 m (6.30 ft)
Stagger 0.17 m (0.56 ft)
Total Wing Area 54 sq m (581 sq ft)
General: Length 8.60 m (28.21 ft)
Height 3.27 m (10.73 ft)
Useful Load 488 kg (1076 lb)
Loaded Weight 1350 kg (2977 lb)
Maximum Speed: 120 km/hr (74.5 mph)
Climb: 1000m (3,281 ft) in 7 min 30 sec


Oeffag C.I Series 51

  The LFT awarded Oeffag its first production contract on 17 July 1915, specifying one prototype (50.02) and 24 C.I biplanes numbered 51.01 to 51.24. Four production machines were in assembly in December 1915. The first C.I (51.01) arrived at Aspern for flight testing in January 1916. Acceptance was delayed until 24 March 1916 because a suitable company test pilot was not available. The last aircraft were accepted in June 1916.
  The C.I, powered by a 160 hp Daimler engine, was assigned to the newly established Fliks 25 and 27 in April-May 1916 and later to Fliks 9, 11, and 18 on the Galician (Russian) plain where the terrain was flat and undemanding. Popularly known as the "Skodaflugzeug", the C.I was a stable, safe, and solidly-constructed aircraft, regarded as ideal for radio-spotting duties because of its low speed and pleasant flight and landing characteristics, but for air combat it was considered sluggish. In late 1916, the C.I was withdrawn; some were equipped with dual controls and issued to Fliks 6, 14, 20, 23, 31, 43, and 49 and to Fleks 6, 10, and 11 as advanced trainers. Twenty-two C.I trainers were still in service as of September 1917, and eight in August 1918 - some flying airmail between Aspern and Lemberg. Seven survived the war and were offered for sale by the Austrian government in 1920.

Oeffag C.I Series 51 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 14.58 m (47.83 ft)
Span Lower 13.90 m (45.60 ft)
Chord Upper 2.30-2.00 m (7.55-6.56 ft)
Chord Lower 2.00 m (6.56 ft)
Dihedral Upper 2 deg
Dihedral Lower 2 deg
Sweepback Upper 9 deg
Sweepback Lower 9 deg
Gap 1.93 m (6.33 ft)
Stagger 0.17 m (0.56 ft)
Total Wing Area 54 sq m (581 sq ft)
General: Length 8.40 m (27.56 ft) (less propeller)
Height 3.27 m |10.73 ft)
Track 2.20 m (7.22 ft)
Loaded Weight 1350 kg (2977 lb)
Maximum Speed: 125 km/hr (78 mph)
Climb: 1000m (3,281 ft) in 7 min

Oeffag 50.08 to 50.12

  The four Oeffag-Saliger "high-performance" reconnaissance prototypes, designated 50.08 to 50.11 (Oeffag Type AF) and powered by a 185 hp Daimler engine, were designed by Ingenieurleutnant Karl Saliger. Work had begun in January 1917 when he came to Oeffag from Flars. By the time the contract was signed in May 1917, one prototype was already undergoing flight trials. In fact, by 19 March sufficient flight data had been gathered for Flars to report that the 50.08 prototype was unfit for field service because of dangerous flight characteristics. It was necessary for Saliger to redesign the wings with a new airfoil section and change the fin and rudder. The modified 50.08 was commissioned on 31 May 1917, and the flight evaluation was successfully completed by the end of June. Only the static load tests stood in the way of releasing the design for production.
  The second prototype, 50.09, was expected to be ready for flight tests in early June 1917, after which it was scheduled for armament installation and firing trials in Fischamend. The fourth prototype, 50.11, was reported ready for flight trials in July 1917.
  Oeffag test pilot Hans Matti flew the third prototype, 50.10, on the maiden flight on 28 June 1917. During a flight demonstration at Aspern on 16 July 1917, the 50.10, piloted by Matti with Saliger as passenger, went into a low altitude spin and crashed, killing both occupants. The court of inquiry recorded that the 50.10 "had functioned splendidly in the previous 38 flights" and the crash officially was attributed to pilot error. It should be noted that Matti's father investigated the crash and found that the control wires had been partially filed through. The culprit was never found. Bereft of Saliger's leadership, the proposed order of 48 Oeffag Type AF aircraft was cancelled by Flars.
  Yet the program remained alive; perhaps there was some glimmer of hope that the Type AF could be brought up to production standard after all. Major structural changes were made to the Oeffag 50.08 and in September 1917, Hauptmann Fekete, a skilled test pilot, reported a top speed of 175 km/h (109 mph) - equal to the Albatros D.III fighter - but judged the flight characteristics as poor. Lengthening the fuselage was suggested but with Saliger gone, nothing more was done.
  50.08, 50.09, and 50.11 prototypes were sent as instruction airframes to the mechanics school in Wiener-Neustadt in March 1918. 50.11 remained on flight status and crashed on 4 April 1918 at Weikersdorf.
  According to Oeffag documents, the 50.12 biplane, also a Type AF, was powered by a 230 hp Hiero engine and had slightly increased wing area. Believed a replacement for the destroyed 50.10 prototype, the 50.12 is not mentioned in extant Flars records nor have photographs been found, although Oeffag performance records indicate that flight tests may have been carried out.

Oeffag 50.08 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 9.50 m (31.17 ft)
Span Lower 9.50 m (31.17 ft)
Chord Upper 1.40m (4.59 ft)
Chord Lower 1.40 m (4.59 ft)
Maximum Speed: 176 km/hr (109 mph)
Climb: 1000m (3,281 ft) in 4 min 8 sec

Oeffag 50.10 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 9.50 m (31.17 ft)
Span Lower 9.50 m (31.17 ft)
Chord Upper 1.40 m (4.59 ft)
Chord Lower 1.40 m (4.59 ft)
Gap 1.40 m (4.59 ft)
Stagger 0.23 m (0.77 ft)
Total Wing Area 24 sq m (258 sq ft)
General: Length 7.13 m 123.39 ft)
Height 2.64 m (8.66 ft)
Empty Weight 695.8 kg (1534 lb)
Loaded Weight 1066.8 kg (2352 lb)
Maximum Speed: 180 km/hr (112 mph)
Climb: 1000m (3,281 ft) in 4 min

Oeffag 50.12 Specifications
Engine: 230 hp Hiero
Wing: Span Upper 9.50 m (31.17 ft)
Span Lower 9.50 m (31.17 ft)
Chord Upper 1.50m (4.92 ft)
Chord Lower 1.50 m (4.92 ft)
Dihedral Upper 0 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.50 m (4.92 ft)
Stagger 0.28 m (0.92 ft)
Total Wing Area 25.16 sq m (271 sq ft)
General: Length 7.13 m (23.39 ft)
Height 2.63 m (8.63 ft)
Track 2.07 m (6.79 ft)
Loaded Weight 1180 kg (2602 lb)
Maximum Speed: 182 km/hr (113 mph)
Climb: 4000m (13,124 ft) in 19 min 35 sec


Oeffag 50.15

  The Oeffag 50.15 prototype, powered by a 230 hp Hiero engine, was under construction in October 1918. Further information is lacking.

Oeffag 50.03

  The 50.03 prototype, powered by a 160 hp Daimler engine, made its appearance in early 1916. It was similar to the Oeffag C.I but slightly smaller and fitted with a simplified two-bay wing cellule. When the wing failed to pass the static load tests, the prototype was written-off and replaced by a second 50.03 in April 1916.
  Regarded as the C.II series 52 prototype, the second 50.03 was fitted with a constant-chord wing of reduced span, rigged without sweepback or stagger. Flight tests of the 160 hp Daimler-powered prototype commenced in May 1916 at Aspern. The aircraft was rammed on the ground on 30 June 1916, interrupting the flight tests. Series production, which had been halted in April to await the test results, was further delayed while repairs were carried out. Testing was completed in August and the second 50.03 was accepted by the LFT on 7 October 1916. Serving as a trainer, the 50.03 was still in service in November 1917.

Engine: 160 hp Daimler
Wing: Span Upper 12.71 m (41.69 ft)
Span Lower 11.82 m (38.78 ft)
Chord Upper 1.75 m (5.74 ft)
Chord Lower 1.75 m (5.74 ft)
Dihedral Upper 0 deg
Dihedral Lower 0.5 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.58 m (5.18 ft)
Stagger 0 m (0 ft)
Total Wing Area 38 sq m (409 sq ft)
General: Length 9.05 m (29.69 ft)
Height 3.20 m (10.50 ft)
Empty Weight 834 kg (1839 lb)
Loaded Weight 1298 kg (2862 lb)
Maximum Speed: 144 km/hr (89.4 mph)
Climb: 1000m (3,281 ft) in 6 min 10 sec
3000m (9,843 ft) in 32 min


Oeffag 50.06

  Design work on the 50.06 reconnaissance biplane began in September-October 1916. Powered by a 185 hp Daimler engine and reduced in size to increase performance, the 50.06 represented a refinement of the C.II airframe. After Flars engineers inspected the 50.06 in late December 1916, they urged Oeffag to proceed with utmost speed and proposed on 31 January 1917, that provided the flight testing was performed with dispatch, Lohner would also build the type under license. Trials in January-February 1917 demonstrated a respectable rate of climb and speed. After a tail fin recommended by Oberleutnant Oskar Fekete was fitted, the project was suddenly stopped for unknown reasons. No further development was undertaken.

Oeffag 50.06 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 10.18 m (33.40 ft)
Span Lower 10.18 m (33.40 ft)
Chord Upper 1.57 m (5.15 ft)
Chord Lower 1.57 m (5.15 ft)
Dihedral Upper 0 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.60 m (5.25 ft)
Stagger 0 m (0 ft)
Total Wing Area 29.5 sq m (318 sq ft)
General: Length 8.00 m (26.25 ft)
Height 2.80 m (9.19 ft)
Empty Weight 900 kg (1985 lb)
Loaded Weight 1205 kg (2657 lb)
Maximum Speed: 157 km/hr (97.5 mph)
Climb: 1000m (3,281 ft) in 4 min 8 sec


Oeffag 50.07

  The Oeffag 50.07 prototype was a lightened C.II airframe (ex 52.82) fitted with a 200 hp Hiero engine for performance evaluation. The prototype made its appearance in February 1917 and remained under investigation until June, at which time the static load calculations were approved by Flars. The 50.07 demonstrated improved performance but the Oeffag C.II biplanes were unpopular with aircrews, making it inadvisable to proceed with a Hiero-engined version. After service with Flik 59/D and as a trainer with Schulkompagnie 2, the 50.07 was written-off in July 1918.

Oeffag 50.07 Specifications
Engine: 200 hp Hiero
Wing: Span Upper 12.71 m |41.69 ft)
Span Lower 11.82 m (38.78 ft)
Chord Upper 1.75 m (5.74 ft)
Chord Lower 1.75 m (5.74 ft)
Dihedral Upper 0 deg
Dihedral Lower 0.5 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.58 m (5.18 ft)
Stagger 0 m (0 ft)
Total Wing Area 38 sq m (409 sq ft)
General: Length 9.05 m (29.69 ft)
Height 3.27 m (10.73 ft)
Useful Load 420 kg (926 lb)
Loaded Weight 1240 kg (2734 lb)
Maximum Speed: 162 km/hr (101 mph)
Climb: 1000m (3,281 ft) in 5 min


Oeffag C.II Series 52 and 52.5

  Oeffag signed a production contract on 8 February 1916 to supply 32 C.II reconnaissance biplanes, numbered 52.01 to 52.32 and powered by the 160 hp Daimler engine. Production, scheduled for completion by 30 April 1916, was interrupted in April to await the flight test results of the second 50.03 prototype. It was not until August 1916, after the damaged 50.03 was repaired and tests concluded, that C.II production resumed. The first nine series aircraft were accepted in October 1916. Because the C.II failed to meet performance specifications, Oeffag was assessed a penalty payment.
  Although the Oeffag C.II represented a considerable design refinement over the C.I, its performance (especially climb) and maneuverability were below expectations. The C.II series 52 aircraft were dispatched to the Russian Front to serve singly with Fliks 3, 5, 13, 14, 18, 20, 22, 25, 27, and 30, replacing the older Aviatik types. They were used mainly for close reconnaissance and radio spotting, whereas the Brandenburg C.I, with its superior altitude and climb performance, was preferred for long-range work.
  Production was already under way when, on 4 December 1916, Flars ordered a second batch of 32 Oeffag C.II biplanes, numbered 52.50 to 52.81. The type was known as the "lightened series 52," the modifications of which had been tested in the Oeffag 50.07 prototype. Although a 185 hp Daimler engine was specified, operational records show that most of the C.II series 52.5 aircraft were flown with 160 hp engines installed. Deliveries, scheduled to commence in October and end on 28 November 1916, did not begin until February 1917 and ended in June. The C.II series 52.5 aircraft were assigned to Fliks 5, 11, 13, 18, 22, and 26 on the Russian Front, to Fliks 31, 36, and 44 on the Rumanian Front, and Flik 6 in Albania.
  Structurally, the C.II was designed for efficient production and ease of rigging. But in the field the type was roundly criticized. Flik 18 reported that "the observer's cockpit is too small and provides insufficient space for ammunition, bombs, camera, map cases, carbine, machine gun, and flare pistol. The aircraft has sluggish controls and is unsuited for combat. The flat glide and high landing speed are a disadvantage on small airfields." Other Fliks criticized the poor visibility, indifferent maneuverability, slow speed, and the weak plywood-covered fuselage. Beginning 1917, the older C.II aircraft, some modified for dual control, were assigned to various Fliks and Fleks as advanced trainers. In August 1918, six C.II trainers were at the Front and 14 flew military airmail routes. After the war, a few were seen in Polish and Czechoslovakian military service.

Oeffag C.II Series 52 Specifications
Engine: 160 hp Daimler
Wing: Span Upper 12.71 m (41.70 ft)
Span Lower 11.82 m (38.78 ft)
Chord Upper 1.75 m (5.74 ft)
Chord Lower 1.75 m (5.74 ft)
Dihedral Upper 0 deg
Dihedral Lower 0.5 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.58 m (5.18 ft)
Stagger 0 m (0 ft)
Total Wing Area 38 sq m (409 sq ft)
General: Length 8.40 m (27.56 ft) less propeller
Height 3.27 m (10.73 ft)
Track 2.22 m (7.28 ft)
Loaded Weight 1205 kg (2657 lb)
Maximum Speed: 140 km/hr (87 mph)
Climb: 1000m (3,281 ft) in 6 min 19 sec
3000m (9,843 ft) in 28 min

Austro-Hungarian Helicopter Development

  The concept of a vertical aircraft or helicopter (Hubschrauber) began to challenge the imagination of Austro-Hungarian scientists toward the end of the 19th century. Noteworthy are the investigations of Josef Popper-Lynkeus, Anton Jarolimek, Professor Georg Wellner, and Wilhelm Kress. In 1894, Wellner experimented with a rotating-wing model that achieved a lift coefficient of 15 kg per horsepower. Kress built a small 33 kg model with counter-rotating propellers powered by an electric motor. In 1895 his associate, Dr. Waechter, successfully demonstrated the model indoors and out to the Technical Military Committee. Subsequently, Kress proposed a man-carrying helicopter weighing 325 kg driven by a 20 hp engine. From these rough beginnings, ideas were generated that would find their realization in time of war.
  Major Stephan Petroczy von Petrocz, the commander of the Lehr Bataillon in Wiener-Neustadt, conceived the idea of replacing the hydrogen-filled observation balloon by a motor-driven helicopter. To this end, in April 1916, he met with Austro-Daimler director and chief engineer Ferdinand Porsche, several of his assistants, and Oeffag director Karl Ockermuller and Diplom-Ingenieur Karl Balaban to discuss the feasibility of building such an aircraft. The result was that Petroczy submitted a proposal to the LFT command on 28 April 1916, calling for development of a captive (tethered) helicopter for use as a static observation platform. The advantages cited were: less danger of fire, less conspicuous and smaller target while aloft, increased operational readiness, elimination of expensive hydrogen generating equipment, and fewer ground-handling personnel required. The belief that, compared to a balloon, the tethered helicopter was more resistant to wind shear was an optimistic dream.
  Power was to be supplied by a 300 hp electro-motor that Daimler was developing for aircraft use. The war ministry approved the project on 5 May 1916. Oeffag was funded to build several experimental, rotating test rigs and to investigate the operating parameters of large-diameter airscrews or rotors. It soon became apparent that the key to success lay in developing a high-efficiency airscrew. The best available had an efficiency of 61 percent, whereas 90 percent or better was required. Balaban moved to Fischamend to work with Leutnant Oskar von Asboth in Professor Knoller's propeller test facility. The result was the perfection of large helicopter rotors up to 8 meters (26.2 ft) in diameter using the highest quality mahogany and yielding a 90-95 percent efficiency.
  Eager to proceed, the Fliegerarsenal (Flars) issued specifications calling for a tethered helicopter carrying one observer and a large parachute for the entire aircraft. An operating altitude of 500 to 1000 meters (1,640-3,281 ft) in wind conditions up to 14 knots was required. The empty weight was estimated at 580 kg, plus the weight of the tethering cable (1000 meters at 150 kg) and the vertical wind component on the cable (230 kg) brought the total weight to 960 kg. With an estimated lifting force of 1200 kg, the reserve lift of 240 kg was deemed sufficient for one machine gun, camera, and telephone. Writing in 1922, Balaban felt that such rigid specifications hampered development. It would have been wiser to complete the propeller-rotor development and experiment with flying models first and then write the specification based on experienced! At the time the helicopter work was beginning to bear fruit, Petroczy was promoted to command Flars (mid-1917), enabling him to divert additional funds into his pet project. He proposed building two manned, and two smaller, unmanned helicopters of different configuration.


PKZ 1 Helicopter

  Oberleutnant Dr. Theodor von Karman (later of Cal Tech fame) and Ingenieurleutnant Wilhelm Zurovec, both attached to Flars, were assigned the task of constructing a prototype helicopter applying the latest information from the propeller laboratory. Eschewing endless theoretical calculations, Karman and Zurovec proceeded with empirical trials. As first envisaged, the tethered helicopter had 10 to 12 lifting rotors arranged in a circle, but the problem of weight and complexity reduced the final choice to a four-rotor design. After testing rubber-band powered models without success, Zurovec conceived a unique compressed air motor (weighing 4 kg and developing 6 hp at 2400 rpm) which enabled him to construct a 35 kg flying model. Starting in June 1917, flight tests explored various stabilizing surfaces, center of gravity shift, and rotor configurations. Unable to achieve dynamic stability with one or two tethering cables, Karman and Zurovec found that a three-cable system gave the best results. A further 50 flights, ranging in height from 10 to 15 meters, were performed in the great balloon hangar at Fischamend between July 1917 and March 1918.
  Meanwhile, on 21 August 1917, the MAG company in Matyasfold had been given the task of building a full-scale, manned helicopter based on the Karman-Zurovec model work. Having little financial incentive and directed by the military bureaucracy, MAG progress was slow, to some degree due to late delivery of the Daimler electro-motor. Completion, scheduled for October, did not occur until February 1918. The aircraft, called a Schraubenfesselflieger (SFF - rotor-driven tethered aircraft) was identified in post-war literature as the Petroczy-Karman-Zurovec PKZ 1. The design was patented jointly by Karman and Zurovec (German patent 346,425, dated 28 June 1917). Karman remained as project director, but it appears that Zurovec began work on his own PKZ 2 helicopter project in November 1917. The PKZ 1 motor weighed 195 kg and produced 190 hp at 6000 rpm - 60 hp less than projected because the winding insulation was of inferior quality. In flight, power would have been transferred by an aluminum cable 800 meters long. On the first test in Fischamend (date unknown), the PKZ 1 (empty weight 650 kg) took off with surprising abruptness at a rotor speed of 700 rpm and rose to the maximum tethered height of 50 cm. Next, three men climbed aboard and the helicopter easily hovered at the limit of the restraining cables. After 15 minutes into the fourth flight, the over-burdened motor burned through. With high-grade electrical copper and quality insulation impossible to obtain, Daimler was unable to repair the motor. Since the private initiative of Liptak had sped the PKZ 2 to completion, the PKZ 1 was transferred to the Liptak factory but, lacking a motor, nothing was done. Nevertheless, the PKZ 1 had demonstrated the feasibility of an electric-powered helicopter as predicted by the model tests in Fischamend.

PKZ 2 Helicopter

  The Petroczy-Karman-Zurovec PKZ 2 helicopter, despite its name, was invented by Wilhelm Zurovec for which he alone received German patent No.347,578, dated 12 February 1918. Unlike the PKZ 1, which was government funded, the PKZ 2 was privately financed by the Hungarian Bank and the firm of Dr. Liptak & Co AG, a large iron foundry and steel fabricator located near Budapest which established an experimental section under Zurovec's direction in late 1917.
  In the design of the PKZ 2 helicopter, Zurovec incorporated the concept of using counter-rotating rotors to cancel torque effects. Each rotor, with a diameter of 6 meters (19 ft 8 in), represented an ingenious combination of old-world craftsmanship with modern applied engineering. Power was supplied by three 100 hp Gnome rotary engines, that drove the rotors at 600 rpm through a common gearbox. The light, tubular airframe, easily disassembled for transport, rested on a patented central air-bag cushion (1 meter diameter) and three smaller cushions mounted on the outriggers. The cushions were kept inflated by an air pump attached to the rotor drive. Three tethering cables affixed to the outriggers ran through pulleys anchored in the ground and were controlled by separate, electric winches. The total weight of the PKZ 2 with fuel for one hour, but without observer and machine gun, was approximately 1200 kg. Two forms of parachute rescue were planned. One was to carry the observer and aircraft safely to earth, and the other was a cannon-launched parachute that would clear the rotors and lift the observer to safety.
  The PKZ 2 was test flown for the first time at the Liptak factory on 2 April 1918. After several flights, one lasting up to one hour, tests were suspended on 5 April because engine power was insufficient to permit safe hovering above 1.2 meters height. The Gnome engines were replaced by three 120 hp Le Rhones. Flight testing continued from 17 to 21 May, during which flights between 10 and 50 meters altitude were recorded. During periods of calm weather and smooth engine operation, the excess lift measured at ground level was 150 to 200 kg. As the PKZ 2 climbed, the loss of ground effect and the increase in tethering cable weight steadily reduced the excess lift. Yet, as long as excess lift sufficed to maintain proper cable tension, the PKZ 2 remained in stable hovering flight. At higher altitudes, the excess lift became marginal, causing the machine to slowly oscillate with increasing amplitude. Provided the tethering cables were retracted at about 1,5 meters/second, the oscillations to cease in about 15 to 20 seconds.
  On 10 June 1918, Zurovec was called upon to demonstrate the PKZ 2 for high ranking military authorities. Although the rotary engines had recently been overhauled, their operation the day before was erratic, and Zurovec, fearing the worst, was reluctant to proceed. But what could a mere Leutnant do against the weight of official brass eager to see the wonder machine fly? Taking advantage of the zero wind conditions, the PKZ 2 with the observer's basket in place took-off at 5:40 am and twice rose to 7-8 meters height, showing "considerable rocking motion." The basket was removed and the PKZ 2 took off again at 6:07 am in a wind of 6-7 meters per second, climbing to a height of 12 meters. Due to overheating, the engine power dropped off and the helicopter began to pitch with increasing frequency until the tether-winch crew could no longer control the machine. The PKZ 2 crashed from two meters height, severely damaging the airframe and splintering the rotors. In a careful review of progress to date, Uzelac, realizing that the technical problems were too complex to resolve quickly, cancelled the project on 21 June 1918. Zurovec, Karman, and Liptak were directed to compile a record that would be a basis for further investigation when peace returned. Zurovec, refusing to accept defeat, devised a method to water-cool the rotary engines! He reported on 1 September that the PKZ 2 helicopter would be ready for further testing on 1 November 1918. By then it was too late.


Karman-Zurovec Remote-Control Helicopter

  An unmanned helicopter design based on the Karman-Zurovec concept was proposed in September 1917. Driven by an electric motor, it was designed to carry aloft meteorological instruments and wireless equipment for gathering weather data and communicating in mountainous areas. Flars reported that the remote-control helicopter, now powered by a single Gnome rotary engine, would be ready for flight testing in mid-February 1918. Further information is lacking.

Phonix 20.10

  In response to the Kampflugzeug (battleplane) program of August 1914 (see Lloyd 40.06), Phonix submitted a proposal for a twin-engined biplane that, after further refinement, was approved by Flars in July 1915. Construction began in January 1916 and the completed aircraft, designated 20.10, was rolled out in September. The crew consisting of pilot and two gunners was housed in a narrow fuselage that had no provision for bombs. Two 200 hp Hiero engines were mounted on a framework independent of the wing structure and the fuselage was raised above the lower wing for aerodynamic reasons.
  Test reports concerning the 20.10 prototype have not been found. Reviewing the program in December 1916, Flars could see no useful military function "for what was basically a 1914 design", but requested completion of modifications for purposes of testing and possible use as a trainer. Returned to the factory for installation of a strengthened undercarriage and rudders of increased area, the 20.10 was reported complete on 14 July 1917 and arrived at Aspern on 22 November 1917. Flight testing, if any, was of short duration, for in December the damaged prototype was placed in storage. The provisional order of 14 battleplanes, reduced from 24 in February 1916, was cancelled.


Phonix 20.11 and 20.12

  The Phonix proposal for a triplane bomber configured to the Flars "large bomber program" guidelines (see Lloyd 40.08) was dated 3 March 1916. Phonix received a contract on 6 March 1916 to build two prototype bombers, designated 20.11 and 20.12. Designer Kirste had located the side fuselages between the lower wings, a more sensible approach than the awkwardly-placed fuselages of the Lloyd 40.08. At Flars' request to increase the field of fire, Kirste submitted an alternate layout with raised fuselages, but common sense prevailed and the original design was proceeded with - no doubt reflecting the lessons learned from the 40.08 ground tests. Construction of two bombers began in April 1916. Allowing work to continue on the 20.11 prototype, Flars however halted work on the 20.12 (nacelle and fuselages complete) in September 1916 and cancelled manufacturing plans by assigning the series 25 designation, originally reserved for the production bomber, to the Knoller C.I(Ph).
  Construction of the 20.11 prototype went slowly. The final layout drawing dated February 1917 shows low side fuselages fitted with raised gunner's positions. A 300 hp Daimler V-12 pusher engine was mounted in the center nacelle and two 160 hp Daimler engines were installed in the side fuselages. A concerted effort to finish the 20.11 began in June 1917 but Flars, admitting its limited military value, cancelled the project in August, freeing Phonix to devote its energies to more important tasks. The unfinished 20.11 and 20.12 airframes were sent to the Eger depot in January 1918 for disposal.

Phonix 20.11 Specifications
Engine: 300 hp Daimler & 2 x 160 hp Daimler
Wing: Span Upper 24.00 m (78.74 ft)
Chord Upper 2.30 m (7.55 ft)
Chord Middle 2.30 m (7.55 ft)
Chord Lower 2.30 m (7.55 ft)
Gap Upper 1.50 m (4.92 ft)
Gap Lower 1.50 m (4.92 ft)
Total Wing Area ca 120 sq m (1291 sq ft)
General: Length 12.20 m (40.03 ft)
Empty Weight ca 2400 kg (5292 lb)
Loaded Weight ca 4800 kg (10,584 lb)

Phonix 20.14

  In late 1916, at a time when the first Phonix-built Brandenburg D.I fighters were under construction, Diplom-Ingenieur Kirste was already busy adapting a wireless Nieuport wing cellule to the airframe to improve the flight characteristics. The Nieuport sesquiplane configuration had made a deep impression on German and Austro-Hungarian engineers, but most were unaware that the design worked best with light, rotary-engined fighters because in-line engined versions were simply too heavy. The drawings and technical specifications for the "improved D.I" were finished in November 1916 and one month later, the prototype was rolled out. Kirste had modified a production D.I airframe (28.48) by raising the fuselage to the level of the upper wing, thereby eliminating the center-section struts. The area of the upper wing was increased. The narrow lower wing was supported by a single V-strut and a slanted fuselage brace. The 28.48 prototype, powered by a 185 hp Daimler engine, was tested by Hauptmann Karl Nikitsch. A crash on 16 January 1917 damaged the prototype before the trials were completed.
  The rebuilt airframe, now designated 20.14, was fitted with a new, longer fuselage, modified ailerons and a redesigned tail. A pair of additional wing struts served to dampen vibration. Flight trials which began in June 1917 demonstrated speed superior to the production Brandenburg D.I(Ph) but the rate of climb was inferior to that recorded by the Sparmann-winged Phonix 20.15 prototype. In spite of structural simplicity, reduced drag and better visibility, Phonix soon jettisoned the sesquiplane concept in favor of Sparmann's more robust and efficient wing cellule.
  On 20 August 1917, the 20.14, on loan to the Navy, was reported damaged by Linienschiffsleutnant Wenzel Wosecek during a night landing exercise at Trieste. Another crash was reported in October 1917, after which the 20.14 was repaired and, according to unconfirmed reports, sold to the Navy.

Phonix 20.14 (28.48) Specifications (First Version)
Engine: 185 Daimler
Wing: Span Upper 8.60 m (28.21 ft)
Span Lower 6.00 m (19.68 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.00 m (3.28 ft)
Dihedral Upper 0 deg
Dihedral Lower 2 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.40 m (4.59 ft)
Total Wing Area 19.5 sq m (210 sq ft)
General: Length 6.30 m (20.67 ft)
Height 2.73 m (8.96 ft)
Track 1.72 m (5.64 ft)
Empty Weight ca 665 kg (1466 lb)
Loaded Weight ca 920 kg (2029 lb)


Phonix 20.16

  In February 1917, Kirste designed an improved Nieuport wing cellule for the 20.16 fighter prototype. The wings were given a high-lift profile and refined wingtip contours. The upper wing was set lower on the fuselage for better visibility. The fuselage was taken from production airframe 28.73. In spite of using the more powerful 200 hp Daimler engine, the Phonix 20.16 did not demonstrate acceptable fighter characteristics when tested in April-May 1917, effectively putting a halt to development of the sesquiplane concept.
  The 20.16 was returned to Phonix for modification in June. Further improving on the 20.15 cellule, Sparmann changed the rib profile and made the lower and upper wings of unequal chord. A re-designed center section provided greater strength. After flight tests and inspection by Uzelac in August 1917, the 20.16 was pronounced "ripe for production." Considered the true prototype of the Phonix D.I fighter, 20.16 flight investigation continued through February 1918.

Phonix 20.16 Specifications (First Version)
Engine: 200 hp Daimler
Wing: Span Upper 9.60 m (31.50 ft)
Span Lower 6.60 m (21.65 ft)
Chord Upper 2.00 m (6.56 ft)
Chord Lower 1.20 m (3.94 ft)
General: Track 1.72 m (5.64 ft)

Phonix C.I Series 121

  The development of the Phonix C.I can be traced back to the Brandenburg C.II 66.51 prototype that in early 1917 was undergoing flight test at Aspern. On 9 March 1917, Phonix received a contract to build 96 biplanes based on the Brandenburg C.II 66.51. The partially-completed airframe, designated Brandenburg C.II(Ph) 121.01, was inspected by Flars engineers on 11 May 1917, but work was stopped because Flars cancelled the Brandenburg C.II program later that month.
  According to Kirste, the complex, star-strutted wing was replaced on the original Brandenburg C.II(Ph) 121.01 prototype by a Sparmann wing cellule - a lighter, single-bay structure similar to that developed for the Phonix D.I fighter. A second prototype, designated 121.02, was given Sparmann wings of increased span and the pilot's view was enhanced by lowering the upper wing and moving his seat aft and higher. Both prototypes were powered by a 185 hp Daimler engine. The modified 121.01 prototype was flight tested at Aspern in June 1917, demonstrating longitudinal stability superior to the 66.51, but inferior performance. Nor did the 121.02 prototype which arrived at Aspern in July fare better.
  In the meantime, Flars had changed the original contract to 24 aircraft, based on a Kirste proposal for a new design, known as the Phonix C.I, that, by virtue of the powerful 230 hp Hiero engine, promised improved performance and flight characteristics. The first true Phonix C.I prototype (designated 121.02) appeared at Aspern for flight tests in August 1917. It was joined by the second prototype (121.01) at a later date. They were fitted with a two-piece upper wing, a cabane center section, and diagonal struts bracing the wingtips. The fuselage was completely re-designed. The key to success was the decision to install the powerful 230 hp Hiero engine. After flight tests were satisfactorily completed, Phonix received a second contract for 24 aircraft on 19 October 1917.
  When the Phonix C.I program became seriously bogged down in late 1917 (for reasons unknown), Uzelac ordered 40 UFAG C.I(Ph) series 123 biplanes from Phonix as insurance against failure. The fact that the wing cellule failed the static load test on 7 March 1918, almost a year after the C.I program had begun, is an indication that something was amiss. The problem was resolved by strengthening the wing struts, thus allowing 17 Phonix C.I biplanes to be accepted that month.
  In April-May 1918, the first Phonix C.I aircraft were dispatched to the Front for combat evaluation. In spite of the fact that the Army High Command had frozen production orders until the C.I was proven sound, Uzelac, convinced of its qualities, had ordered a further 60 machines in early April but too late to avoid a substantial output drop in mid-1918. Nevertheless, Uzelac's defiance of orders was soon vindicated when the initial reports of universal and enthusiastic approval for the Phonix C.I were received from the Front in mid-May 1918. Flars responded by placing large production orders. In the long run, the Army Command preferred the Phonix C.I because it was easier to fly, climbed higher, and was more robust than the UFAG C.I. This was reflected in the August 1918 production program in which the Phonix C.I appears as the dominant reconnaissance aircraft. In an ironic about-face, the LFT proposed that UFAG deliver the Phonix C.I beginning December 1918!
  The signed and proposed orders for the Phonix C.I as of 31 August 1918 totalled 565 aircraft composed of the following:
Qty Manufacturer Series No. Order Date First Acceptance
24 Phonix 121.01-24 9 Mar 1917 Mar 1918
24 Phonix 121.25-48 11 Jul 1917 Apr 1918
112 Phonix 121.49-160 10 May 1918 Aug 1918
200 Phonix not assigned Aug 1918 Jan 1919 (a)
100 Lloyd 49.01-100 Aug 1918 Dec 1918
25 Lloyd not assigned Aug 1918 Mar 1919 (b)
80 UFAG not assigned Aug 1918 Dec 1918 (b)
(a) approved by LFT, awaiting War Ministry approval.
(b)proposed by LFT.
  The Army chief of staff reported on 10 August 1918 that "the Phonix C.I is such a superb aircraft that for most assignments one can dispense with fighter protection." In fact, at higher altitudes it was faster than the feared Sopwith Camel fighter. The maneuverable C.I was armed with a forward-firing, synchronized machine gun and an observer's gun which covered a wide field of fire. The observer's tubular gun ring, installed on aircraft up to 121.10, was replaced by an integral Priesel gun ring on all other machines. Allied fighter pilots often mistook the C.I for a fighter and when attacking from the rear received an unpleasant surprise. In this manner Italy's leading ace, Maggiore Francesco Baracca, was shot down on 19 June 1918 by observer Oberleutnant Arnold Barwig and Zugsfuhrer Max Kauer of Flik 28/D flying aircraft 121.17. To fully exploit the splendid qualities of the C.I, Flars engineers installed a variety of equipment. Some aircraft were armed with bomb racks under each wing, capable of carrying six 12 kg (26 lb) bombs, a feature tested on aircraft 121.89 in August 1918. Beginning with airframe 121.49, a Klemperer camera mounting was built into every aircraft. Wireless transmitting equipment, exhaust silencers and flame suppressors for night work became standard. A universal fuselage adapted to take a variety of equipment and a modified tailplane were introduced with airframe 121.111.
  The Phonix C.I was operational on the Piave Front with Fliks 4/D, 5/F, 12/Rb, 19/F, 28/D, 34/D, 52/D, 57/Rb, 58/F, 62/K, and 103/G, and in the Tirol with Fliks 10/F, 11/F, 15/F, 16/D, 17/D, and 27/F. While losses in air combat were few, the attrition rate was high and only six Phonix C.I aircraft were at the Front on 20 October 1918. A contributing factor was the fact that the major production acceptances did not occur until September-October 1918 and many of these aircraft arrived too late or were in transit when the war ended. By virtue of its overall excellence, the Phonix C.I was slated to become the primary general-purpose aircraft had the war continued into 1919. It is a pity that this formidable aircraft, whose development had started in mid-1917, did not reach frontline units sooner and in greater numbers.
  After the war, a few Phonix C.I biplanes were operational with the Czechoslovakian air service. The post-war Austrian Army air service requested 30 Phonix C.I biplanes for police service, but in accordance with peace treaty stipulations all remaining aircraft were destroyed. At the invitation of the Swedish newspaper Dagens Nyheter and the Royal Swedish Aeronautical Society, Edmund Sparmann flew aircraft 121.105 to Stockholm for demonstration on 6 July 1919. It was purchased by the Swedish air service in December 1919. Between 1920 and 1928 the Swedish government aircraft factory at Malmen built 32 C.I derivatives, known as the Dront, under license. The last Dront was written off in 1935, surely a tribute to the design's integrity.

Phonix C.I Series 121 Specifications
Engine: 230 hp Hiero
Wing: Span Upper 11.00 m (36.09 ft)
Span Lower 8.60 m (28.21 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.50 m (4.92 ft)
Dihedral Upper 1 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.59 m (5.22 ft)
Total Wing Area 29.0 sq m (312 sq ft)
General: Length 7.60 m (24.93 ft)
Height 2.95 m (9.68 ft)
Empty Weight 820 kg (1808 lb)
Loaded Weight 1240 kg (2734 lb)
Maximum Speed: 170-175 km/hr (105.5-109 mph)
Climb: 1000m (3,281 ft) in 4 min 30 sec
2000m (6,562 ft) in 10 min 45 sec
3000m (9,843 ft) in 20 min 35 sec
4000m (13,124 ft) in 34 min 50 sec
5000m (16,405 ft) in 55 min


Phonix Reconnaissance Biplane (Type 13)

  In an authoritative article published in 1919, mention is made of the Phonix Type 13, a two-seat biplane of C.I configuration but with slightly reduced overall dimensions and weight, that reputedly was built and flown. Further details are lacking.

Phonix Type 13 Specifications
Engine: 230 hp Hiero
Wing: Span Upper 9.50 m (31.17 ft)
Chord Upper 1.60m (5.25 ft)
Chord Lower 1.60 m (5.25 ft)
Gap 1.50 m (4.92 ft)
Stagger 0.62 m (2.03 ft)
Total Wing Area 23.92 sq tn (257 sq ft)
General: Length 7.4 m (24.28 ft)
Track 1.90 m (6.23 ft)
Empty Weight 770 kg (1698 lb)
Loaded Weight 1200 kg (2646 lb)
Maximum Speed: 175 km/hr (109 mph)
Climb: 1000m (3,281 ft) in 3 min 45 sec


Phonix C.I(Ll) Series 49

  The long-range production program issued on 31 August 1918 projected the Phonix C.I as the sole reconnaissance aircraft to be built beyond March 1919. Therefore Flars ordered 100 Phonix C.I(Ll) series 49 biplanes from Lloyd in August 1918, with a further 25 pending War Ministry approval. The Phonix C.I 121.53, intended as a pattern aircraft, was flown to Aszod in September 1918, where assembly was well under way. As of 31 October 1918, when information from Hungary ceased, construction of 20 Phonix C.I(Ll) biplanes was reported "in progress" but how many were completed is not known.
  Approximately 10 Phonix C.I(Ll) biplanes saw service with the Hungarian Red Airborne Corps in clashes with Czech and Rumanian forces during 1919. These aircraft were powered by the 200 or 225 hp Daimler (MAG) engines, rather than the customary 230 hp Hiero. At the time the national airmail organization, MAeFort was established in May 1920, twenty Phonix C.I(Ll) biplanes, registered H-OP-1 to HO-P-20, became part of the inventory. They were ordered destroyed in 1921 by the Inter-Allied Aeronautical Control Commission in observance of the peace treaty stipulations.

Phonix 20.15

  The Phonix 20.15 prototype was the first step towards the Phonix D.I production fighter that was built for the Army and Navy through 1918. Taking German experience into account, Diplom-Ingenieur Sparmann designed a wing cellule that provided the pilot with an uninterrupted field of view and was more robust than the wireless Nieuport system of the 20.14. The 20.15 prototype, modified from the 28.50 airframe and powered by a 185 hp Daimler engine, performed the first test flights in June 1917. The flight characteristics were far superior to the Brandenburg D.I, but the performance had hardly improved. The solution was more horsepower, as exemplified by the Phonix 20.16 prototype. The Phonix 20.15 was assigned to the training command and last reported stored in damaged condition at Flugpark 1 in Wiener-Neustadt. It was offered for sale to Czechoslovakia in April 1920.


Phonix 20.18

  When the new Phonix D.I fighter appeared in October 1917, it was reported as having "superb flight characteristics but only average performance." Phonix engineers were already at work on an improved version, the 20.18 prototype, that weighed about 130 kg (287 lb) less. During comparative trials performed on 19 December 1917, the 20.18 reached 5000 meters (16,405 ft) in 19 minutes versus 28 minutes for the D.I. Flars ordered the type into production as the Phonix D.II (200 hp Hiero) and D.IIa (230 hp Hiero). For armament tests and fine tuning in preparation for manufacture, the 20.18 prototype was evaluated through January-April 1918. It was later redesignated Phonix D.II 322.09 and assigned to the fighter school in Campoformido. In September, the 322.09 (ex-20.18) had a 230 hp Hiero engine installed and was transferred to the Navy under the new designation Phonix D.III, Navy number J 32.

Phonix 20.18 Specifications
Engine: 200 hp Hiero
Wing: Span Upper 9.80 m (32.15 ft)
Total Wing Area 25.0 sq m (269 sq ft)
General: Length 6.85 m (22.47 ft)
Height 2.79 m (9.15 ft)
Empty Weight 635 kg (1400 lb)
Loaded Weight 935 kg (2062 lb)
Maximum Speed: 175 km/hr (109 mph)


Phonix 20.22

  For the forthcoming Fighter Evaluation in July 1918, Phonix prepared five prototypes; 20.22, 20.23, 422.23, 20.24, and 20.25. The first three were standard D.II/D.IIa airframes modified to improve maneuverability, performance, pilot's visibility, and machine gun accessibility. Besides the more-powerful 230 hp Hiero engine, the 20.22 prototype had an upper wing of increased area, a lower wing of reduced span, and ailerons on all wings. The pilot's seat was raised and the machine guns were mounted at eye level. Flight and altitude tests of the 20.22 took place in May 1918. At the Evaluation, Oberleutnant Frank Linke-Crawford, Oberleutnant' Marian Gawel, and Stabsfeldwebel Franz Kuntner flew the 20.22 and were impressed by its maneuverability. On 17 July 1918, Stabsfeldwebel Karl Urban, a Flik 14/J pilot, was killed when the upper wingtips of the 20.22 folded back while executing a sharp loop. Flars, noting that similar incidents had occurred at the Front, ordered the wings of all Phonix D.II fighters presently in production to be reinforced.

Phonix 20.22 Specifications
Engine: 230 hp Hiero
General: Empty Weight 685 kg (1510 lb)
Loaded Weight 945 kg (2084 lb)
Maximum Speed: 185 km/hr (115 mph)
Climb: 1000m (3,281 ft) in 2 min 58 sec
2000m (6,562 ft) in 6 min 24 sec
3000m (9,843 ft) in 11 min 46 sec
4000m (13,124 ft) in 16 min 1 sec


Phonix 20.23

  The Phonix 20.23 prototype was adapted from a D.II airframe and powered by a 225 hp Daimler engine; the upper wing was raised slightly to improve the pilot's view and the aileron cables ran through the lower wing. Both Oberleutnant Benno Fiala Ritter von Fernbrugg and Frank Linke-Crawford praised the facile maneuverability and the accessible machine guns after flying the 20.23 during the Fighter Evaluation in July 1918. Fiala, extolling the excellent field of view, recommended that the cabane arrangement be made mandatory for all fighters. Linke-Crawford wrote that "for my squadron I desire a Phonix single-seater with the pilot's view and machine guns located as in the 20.23; ailerons on both wings (20.22 and 422.23) and, if possible, the Gebauer motor machine gun. The bead sight should be replaced by an aiming telescope (English type with large field of view) or the new electrical sight."

Phonix 20.23 Specifications
Engine: 225 hp Daimler
General: Empty Weight 685 kg (1510 lb)
Loaded Weight 965 kg (2128 lb)
Climb: 1000m 13,281 ft) in 2 min 50 sec
2000m (6,562 ft) in 5 min 50 sec
3000m (9,843 ft) in 10 min 30 sec
4000m (13,124 ft) in 15 min 30 sec
5000m (16,405 ft) in 27 min


Phonix 20.28 and 20.29

  On 28 July 1918, Flars ordered Phonix to build two experimental fighters incorporating the improvements demonstrated at the Fighter Evaluation (see 20.22, 20.23, and 422.23) preparatory to placing the type in production as the Phonix D.III series 222.100. Flars allocated two Phonix D.II airframes for modification: 122.12 was re-numbered 20.28 and 222.03 became 20.29, both were powered by the 230 hp Hiero engine. In accordance with the frontline pilots' preferences, the prototypes were fitted with four ailerons to increase maneuverability; the rudder-elevator controls and contours were revised to increase sensitivity and the machine guns were mounted within reach of the pilot. Engine bearers, fuselage frames and engine cowling were strengthened throughout.


Phonix D.I 128, 228 and 328

  In 1917 the LFT began to award large "open" aircraft contracts from which smaller production batches would be drawn down as needed. In March 1917, from an open contract of 264 aircraft, Flars ordered 120 Phonix D.I fighters provided, of course, that the 20.15/20.16 prototype program was successfully concluded. Manufacture began in August 1917 and deliveries, scheduled to end on 31 December 1917, actually did not finish until May 1918. The Phonix D.I, identical with the 20.16 prototype, was fitted with the Sparmann wing cellule and canted wing struts. The plywood-covered, wood fuselage was derived from the Brandenburg D.I but was somewhat longer to accommodate the larger 200-hp Hiero engine. Armament consisted of twin machine guns mounted well forward, alongside the engine.
  Eleven D.I fighters were accepted in October 1917 and the last in April-May 1918. The different series designations simply identified the engine manufacturer and in other respects the fighters were identical, although a few early production models (228.01, 228.02) had a top wing with one less rib between cabane and wing strut:
Phonix D.I 128.01-31 200 hp Hiero
Phonix D.I 228.01-55 200 hp Hiero (Fi)
Phonix D.I 328.01-34 200 hp Hiero (Bd)
  Shortages greatly affected smooth production flow. When Uzelac learned in November 1917 that 50 D.I fighters were in storage awaiting machine guns or installation of the new Zaparka synchronization system, he immediately ordered the aircraft to the Front where LFT armorers could install the armament on arrival. During flight comparison in September 1917, the Phonix D.I was reported as being faster in speed and climb than the Albatros D.III(Oef) and having significantly better flight characteristics than the Aviatik D.I. In October 1917, the German Idflieg reported that the new Phonix D.I deserved notice because "it possesses totally amazing qualities, especially the quickness of maneuver and stability when throttled down. The pilot can stall the aircraft virtually on the spot and drop several hundred meters without losing control."
  Beginning in December 1917, the D.I was flown as an escort fighter with Fliks 4/D, 15/D, 17/D, 48/D, 54/D, and 66/D and as a fighter with Fliks 14/J, 30/J, 60/J, 61/J, and 63/J. Being easy to fly, many two-seater pilots had little difficulty in making the transition to this single-seater and many came to prefer the D.I over other fighters. A number of D.I machines were converted to perform photo-reconnaissance work and in several cases these were fitted with a 230 hp Hiero engine to increase performance. But some fighter units saw the D.I in a different light. Flik 60/J reported in February 1918 that the "D.I is not favored by pilots because the speed and climb are inferior to the Nieuport, SPAD, and Sopwith fighters." Flik 30/J complained that the D.I was too slow (the fighter pilot's eternal lament!) and "almost too stable for quick combat maneuvers." Yet the robustly-built D.I possessed no hidden vices and, unlike the Aviatik D.I, could dive at high speed without fear of structural failure. The fact that 72 Phonix D.I fighters were still operational on 1 August 1918 speaks well for its all-round, if not spectacular, qualities.

Phonix D.I Series 128, 228, & 328 Specifications
Engine: 200 hp Hiero
Wing: Span Upper 9.80 m (32.15 ft)
Span Lower 9.00 m (29.53 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.20 m (3.94 ft)
Dihedral Upper 1 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.51 m (4.95 ft)
Stagger 0.70 m (2.30 ft)
Total Wing Area 25.0 sq m (269 sq ft)
General: Length 6.75 m (22.15 ft)
Height 2.65 m (8.69 ft)
Track 1.70 m (5.58 ft)
Empty Weight 716 kg (1579 lb)
Loaded Weight 951 kg (2097 lb)
Maximum Speed: 178 km/hr (110.5 mph)
Climb: 1000m (3,281 ft) in 3 min 5 sec
2000m (6,562 ft) in 7 min
3000m (9,843 ft) in 12 min 15 sec
4000m (13,124 ft) in 18 min 39 sec
5000m (16,405 ft) in 27 min 39 sec


Phonix D.II Series 122, 222, and 322

  The Phonix D.II fighter which replaced the D.I in production in March 1918 was re-designed to improve performance and maneuverability. About 50 kg (110 lb) were pared from the airframe without changing the basic layout. The lightened cellule had a one-piece upper wing and vertical wing struts. High-aspect ailerons, elimination of dihedral, a new tailplane, and balanced elevators quickened aircraft response. When the tests of the 20.18 prototype were completed in early 1918, Flars ordered 48 fighters with the following series designations:
Phonix D.II 122.01-26 200 hp Hiero
Phonix D.II 222.01-14 200 hp Hiero (Fi)
Phonix D.II 322.01-08 200 hp Hiero (Bd)
  Beginning May 1918, the Phonix D.II became operational with Fliks 9/J, 14/J, 30/J, 55/J, 60/J and 68/J. Several accidents in May were traced to engine bearer failure; although held blameless, Phonix was required to supply reinforcement kits at no charge, and modification was completed in July. An unfortunate incident occurred in June 1918. Scheduled to be re-equipped with Phonix D.II fighters, Flik 43/J performed familiarization flights, in the course of which a pilot was killed because of wing failure. Flik 43/J refused to fly the fighter. Although the Phonix D.II fighter remained operational for the duration of the war and Flik technical reports were positive, the D.II was flown only sporadically. This was primarily because fighter pilots overwhelmingly preferred the more robust, 225 hp Albatros D.III(Oef) series 253 fighter.

Phonix D.II Series 122, 222, St 322 Specifications
Engine: 200 hp Hiero
Wing: Span Upper 9.80 m 132.15 ft)
Span Lower 9.00 m (29.53 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.20 m (3.94 ft)
Total Wing Area 25.0 sq m (269 sq ft)
General: Length 6.75 m (22.15 ft)
Height 2.65 m (8.69 ft)


Phonix D.IIa Series 422

  In March 1918, Flars ordered 48 Phonix D.IIa fighters numbered 422.01 to 422.48. The D.IIa was structurally identical to the D.II but was powered by the new 230 hp Hiero engine. Flight testing was performed with aircraft 122.13, which on 11 May 1918 clocked an exceptional time of 17:20 minutes to reach 5000 meters (16,405 ft). Because of insufficient output of the 230 hp Hiero engine, some 20 percent of the series 422 fighters were delivered with the 200 hp Hiero instead. Like the D.II, the engine bearers proved weak and had to be strengthened in the field.
  The first D.IIa fighters were dispatched to the Front in late May 1918, reaching Fliks 9/J, 14/J, 30/J, 32/D, 43/J, 55/J, 60/J, and 68/J. One D.IIa was flown as a photo-reconnaissance fighter by Flik 37/P. Ten D.IIa fighters were transferred to the Navy (designated J.21 to J.30) and assigned to naval defense flights based at Altura (Pola) and Igalo. The D.IIa was highly regarded by fighter pilots who appreciated the extra power and its rugged construction. Flik 1/J at Igalo pronounced the D.IIa and the Aviatik D.I series 338 as being the only fighters capable of performing interception work. As of 1 August 1918, thirty-four D.IIa fighters were listed in the frontline inventory.

Phonix D.IIa Series 422 Specifications
Engine 230 hp Hiero
Wing Span Upper 9.80 m (32 15 ft)
Span Lower 9 00 m (29 53 ft)
Chord Upper 1 70 m (5.58 ft)
Chord Lower 1 20 m (3 94 ft)
Dihedral Upper 0 deg
Dihedral Lower 0 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.51m (4.95 ft)
Stagger 0.70 m (2.30 ft)
Total Wing Area 25 0 sq m (269 sq ft)
General Length 6.75 m (22.15 ft)
Height 2 65 m (869 ft)
Track 1 70 m (ft)
Maximum Speed 180-185 km/hr (112-115 mph)
Climb. 1000m (3,281 ft) m 3 mm


Phonix D.III Series 222.100

  Among the fighters entered in the July 1918 Fighter Evaluation was a production Phonix D.IIa fighter (422.23) fitted with ailerons on top and bottom wings to enhance maneuverability. Pilots who test flew the fighter recommended it for production provided the inaccessible machine guns were relocated at eye level within arm's reach. Flars notified Phonix that a production order of 100 fighters, tentatively designated "D.II series 222 neu" and powered by 200 hp Hiero (Fi) engine, would receive approval. Eager to make further improvements, Phonix engineers were given approval on 28 July 1918 to modify and test two production fighters (see 20.28 and 20.29) in anticipation of production. The new fighter, known as the D.III, had a revised wing planform and a fuselage designed for accessible machine guns mounted at eye-level.
  On 18 September 1918, Phonix received formal production approval for 100 D.III fighters, numbered 222.101 to 222.200 and powered by the 230 hp Hiero engine. Delivery was scheduled to begin in October 1918 and end in March 1919. In fact, on 27 October 1918, the LFT, desperate for additional aircraft to stem the Allied offensive on the Piave, considered the immediate dispatch to the Front of 61 completed D.III fighters (222.101 to 222.159, 222.163 and 222.164) which were awaiting flight acceptance. But time had run out and none left Aspern. As of 26 February 1919, aircraft 222.101 to 222.174 were stored at Stadlau. These were the cause of a legal suit against the Austrian government by Phonix who, claiming the aircraft had been "de facto" accepted, now demanded full payment.
  In the spring of 1919, Sparmann and Maximilian Perini, both expert pilots, demonstrated a Phonix D.III in Stockholm. It was purchased by the Swedish Army Air Force in April 1920 (Swedish No.935), followed in July by 20 D.III fighters, designated 941 to 979 (odd numbers) and powered by a 200-hp Hiero engine. Three Phonix D.III fighters were still active in 1926.
  The fact that the LFT chose only two fighters for production into 1919 - the Fokker D.VII and the Phonix D.III - stands as a high tribute to Phonix engineering and workmanship.

Phonix D.III Series 222.100 Specifications
Engine: 230 hp Hiero
Wing: Span Upper 9.80 m (32.15 ft)
Span Lower 9.00 m (29.53 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.20 m (3.94 ft)
Dihedral Upper 0 deg
Dihedral Lower 0 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Total Wing Area 25.0 sq m (269 sq ft)
General: Length 6.62 m (21.72 ft)
Height 3.01 m (9.88 ft)
Track 1.79 m (5.87 ft|
Empty Weight 685 kg (1510 lb)
Loaded Weight 951 kg (2097 lb)
Maximum Speed: 180-185 km/hr (112-115 mph)
Climb: 1000m (3,281 ft) in 2 min
3000m (9,843 ft) in 12 min
5000m (16,405 ft) in 24 min

Phonix 20.19 and 20.21

  Designer Eduard Zaparka, who had joined Phonix in late 1917, was responsible for the Phonix 20.19 and 20.21 (Phonix Type 10) prototypes that used the unique wing structure invented by him (see Zaparka fighter). The 20.19 arrived at Aspern for evaluation in January 1918, performing sporadic test flights before it was returned to the factory for installation of new wings in March. On 23 May 1918, the modified 20.19 was flown in competition with three aircraft also powered by the 230 hp Hiero engine: the Phonix C.I 121.44, the UFAG C.I 161.14, and the Brandenburg C.I(Ph) 429.01. As the lightest aircraft of the group, the 20.19 reached 5000 meters (16,504 ft) in 48 minutes; the 429.01 was second with a time of 56 minutes. The 20.19 and 20.21 appeared at the July Fighter Evaluation at Aspern for inspection. In the course of load testing on 19 August 1918, the 20.19 achieved a remarkable 9.1 factor of safety. The second Zaparka prototype, 20.21, fitted with a larger fin, continued flight trials through September.
  A second climb competition convened on 20 September demonstrated the rapid progress made by the Austro-Hungarian aircraft industry. The 20.19 that four months earlier had been first was now eclipsed by four new aircraft: the UFAG 60.03, two improved Phonix C.I biplanes (121.71 and 121.82), and the WKF 80.07, even though the 20.19 had reached 4000 meters (13,124 ft) in 37 minutes. The Phonix-Zaparka aircraft were not included in the 31 August 1918 production calendar. Both the 20.19 and 20.21 were accepted at the war's end to permit Phonix to receive payment for the aircraft.

Phonix 20.19 Specifications
Engine: 230 hp Hiero
Wing: Span Upper 10.50 m (34.45 ft)
Span Lower 8.95 m (29.36 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.40 m (4.59 ft)
Gap 0.91 m (2.99 ft)
Stagger 0.70 m (2.30 ft)
General: Empty Weight 730 kg (1610 lb)
Loaded Weight 1050 kg (2315 lb)
Maximum Speed: 175 km/hr (109 mph|
Climb: 1000m (3,281 ft) in 3 min 36 sec
2000m (6,562 ft) in 8 min 45 sec
3000m (9,84-3 ft) in 16 min 48 sec
4000m (13,124 ft) in 27 min 8 sec
5000m (16,405 ft) in 48 min

Phonix 20.24 and 20.25

  During the winter of 1917, Kirste began design work on a high-performance fighter that represented the "total experience gathered by the aircraft industry during the war." The drawings and specifications were approved by Flars in January 1918. Two prototypes, known as the "Kirste fighters," were built. The 20.24 was powered by a 230 hp Hiero engine and fitted with a new rib section. The 20.25, powered by a 225 hp Daimler engine, retained the D.II rib section and had a slightly larger fin. By ingenious design, Kirste extracted maximum strength from a light and simple airframe. The oval, veneer-covered fuselage, the wide center section and narrow lower wing gave the pilot a superb field of view. An unusual feature was a fire-proof fuel tank mounted between pilot and engine. The prototypes, completed in May, were flight tested in June 1918.
  The 20.24 and 20.25 appeared at the Fighter Evaluation on the last day (13 July) and were available for inspection only because they were not completely ready. Oberleutnant Fiala commended the electrical reflex sight on 20.24 and suggested minor internal changes. According to Phonix records, had the fighter gone into production it would have been designated Phonix D.IV. The prototypes arrived too late to be included in the 31 August 1918 production calendar. Both prototypes were accepted in October 1918 to permit Phonix to receive payment for the aircraft.

Phonix 20.24 Specifications
Engine: 230 hp Hiero
Wing: Span Upper 8.50 m (27.89 ft)
Span Lower 7.50 m (24.61 ft)
Chord Upper 1.50 m (4.92 ft)
Chord Lower 1.50 m (4.92 ft)
Dihedral Upper 0 deg
Dihedral Lower 0 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.65 m (5.41 ft)
Stagger 0.71 m (2.33 ft)
Total Wing Area 23.50 sq m (253 sq ft)
General: Length 6.60 m (21.65 ft)
Height 2.70 m (8.86 ft)
Track 1.40 m (4.59 ft)
Empty Weight 665 kg (1466 lb)
Loaded Weight 950 kg (2095 lb)
Maximum Speed: 185 km/hr (115 mph)
Climb: 1000m (3,281 ft) in 2 min 10 sec
5000m (16,405 ft) in 18 min

Priesel KEP Fighter

  Oberleutnant Guido Priesel, a graduate engineer who had built two prewar aircraft in Hohenelbe, Bohemia joined Flars in February 1915 after he was wounded on active service. As a Flars weapons expert, Priesel was instrumental in developing the Type II VK machine gun canister, bomb racks and release mechanisms, and a successful synchronization system. In April 1917, Priesel was given leave to manage the construction of his third aircraft, a monoplane, as a private venture undertaking of Petera & Sohne in Hohenelbe. The monoplane's fabrication, under the supervision of Leutnant Arthur Olessak, was virtually complete and awaiting installation of a 145 hp Hiero engine which Flars had provided when Priesel stopped the project in September 1917 in favor of a new biplane fighter.
  For Petera, a small coach builder, the project had become too expensive, forcing Priesel to join forces with Karl Hoier, a factory owner in Fischamend who provided financial backing in return for which, it appears, he obtained the rights to Priesel's various patents. The new venture was named Wieland Technische Werkstatte. Olessak, assisted by Leutnant Hans Stephenson and Flars engineer Robert Gabriel, supervised the construction of the Priesel KEP (Kampfeinsitzer Priesel) for which Flars had assigned four workers. Another 16 workers were detached to fabricate 150 observer's machine-gun fixtures designed and patented by Priesel.
  As proposed to Flars, the advantages of the Priesel KEP were improved pilot visibility, minimum weight (less than the Aviatik D.I), an unsynchronized machine gun mounted on the upper wing, a wing cellule free of fuselage interference drag, and minimal wing bracing. Because of the novel design, the static calculations prepared by Stephenson in March 1918 were rejected by Flars. Army pilots were prohibited from flying the aircraft.
  After Priesel was killed in a crash while engaged in Flars weapon experiments on 20 March 1918, Major von Petroczy was given the task of preparing the aircraft for flight testing. According to Stephenson, civilian test pilot Karl Kriger fearlessly flew the aircraft to Aspern on its maiden flight on 6 April 1918 and performed one or two additional flights. In view of unsatisfactory wind tunnel tests, Flars recommended on 5 August 1918 a complete reconstruction, namely replacing the tail empennage, rear fuselage and wing profile and exchanging wing warping for aileron control. A lighter but more powerful rotary engine would replace the 145 hp Hiero engine. These plans never materialized. The Priesel KEP was offered for sale to the Czechoslovakian government in 1920.

UFAG C.I(Ph) Series 123

  In early 1918, when it became apparent that the development of the Phonix C.I was experiencing delays, Uzelac, concerned that the program might fail, ordered Phonix to build 40 UFAG C.I(Ph) series 123 aircraft as insurance. The production was well underway when the contract was signed on 10 May 1918. However, by then the Phonix C.I problems had been solved. LFT records give no reason why the UFAG C.I(Ph) program was allowed to continue at Phonix, but it is likely, since the two companies were closely related and were accustomed to sharing engineering data, that manufacture had progressed beyond cancellation. When queried by the War Ministry as to why the airframes had not been transferred to UFAG, Uzelac replied that this would delay the delivery of the UFAG C.I by two months. Acceptances of the UFAG C.I(Ph), numbered 123.01 to 123.40, began in July and ended in October 1918. About half reached operational service. Twenty-two new aircraft never reached the Front but were stored awaiting disposition in March 1919.


UFAG 60.01

  Engineering work on an improved version of the C.I reconnaissance biplane, slated to become the UFAG C.II, was underway in the summer of 1918. Two prototypes, numbered 60.01 and 60.03, were built and flown. Antal Feher, who tested many UFAG-built machines, recorded that the 60.01, powered by a 230 hp Hiero engine, was basically a modified UFAG C.I that was fitted with ailerons of greater span and a balanced rudder. The dihedral and stagger remained the same. Further information is lacking.


UFAG 60.03

  In July 1918, the drawings and static calculations for the 60.03, the definitive C.II prototype, were completed by Ingenieur Bela Oravecz and airframe assembly was well underway. Similar to the C.I in appearance, the 60.03 had an increased wingspan and an aerodynamically-balanced rudder. As reported in August 1918, the C.II had better glide characteristics and a lower landing speed than the C.I. In a climb competition for 230 hp Hiero-powered aircraft held on 19 September 1918 , the 60.03 was barely beaten by the WKF 80.07, winner of the trials. Flars had plans to produce the C.II, but the war ended before any decision was made. The 60.03 prototype was offered for sale to the Czechoslovakian government in 1920.

UFAG 60.03 Specifications
Engine: 230 hp Hiero (Fi)
Wing: Span Upper 10.30 m (33.79 ft)
Span Lower 9.74 m (31.95 ft)
Chord Upper 1 66 m (5 45 It)
Chord Lower 1.66 m (5.45 ft)
Total Wing Area 28.64 sq m (308 sq ft)
General Track 1 90 m (6 23 ft)
Empty Weight 750 kg (1654 lb)
Loaded Weight 1150 kg (2536 lb)
Climb: 1000m (3,281 ft) in 4 min 45 sec
2000m (6,562 ft) in 10 min 53 sec
3000m (9,843 ftl in 20 mm 46 sec
4000m (13,124 ft) m 31 mm 14 sec


UFAG C.I Series 161

  Hard on the heels of the failed Brandenburg C.II program, UFAG engineers developed the UFAG C.I, which incorporated the best C.II features but eliminated the complex wing struts in favor of a simple wing cellule braced by a single interplane strut. In quick succession two C.I prototypes, numbered 161.01 and 161.02, were built. The partially-completed airframe of 161.01, powered by a 200 hp Hiero engine, was inspected by Flars engineers on 30 May 1917. The second prototype, 161.02, rolled out in June 1917, was identical except for the installation of a more powerful 230 hp Hiero engine and slightly enlarged wing area.
  Promising flight trials performed at Albertfalva and Aspern between June and September 1917 demonstrated satisfactory handling characteristics and excellent performance. Although the static load test on 20 October 1917 showed an acceptable 6.3 load factor, Flars rejected the I-strut interplane bracing and required UFAG to install conventional wing struts. The modification to production standard was completed in November 1917, but the sub-zero weather delayed completion of flight trials until mid-January 1918. The static load test of a production airframe (161.09) was successfully concluded on 18 February 1918.
  By March 1918, eleven C.I biplanes had been accepted and a number were dispatched to Fliks 47/D and 58/D in April for frontline evaluation. Being fast and maneuverable, the C.I was reported eminently suitable for wireless, photographic, and bombing work. Flars responded by placing large production orders which, by the end of May 1918, amounted to 284 aircraft, divided into three batches as shown below. Phonix became involved in the UFAG C.I production because in early 1918 the Phonix C.I was experiencing development problems and Uzelac, concerned the program might not succeed, wanted Phonix to have a back-up production aircraft in place.
Qty Series Numbers Order Date First Acceptance
24 161.01-22 13 May 1917 September 1917 (a)
220 161.31-250 4 Feb/18 May 1918 May 1918
40 123.01-40 18 May 1918 July 1918
(a) Of the first 24 aircraft ordered in May 1917, only 22 were production C.I biplanes and of these, only 20 aircraft were formally accepted by the LFT. It is believed that the two Brandenburg C.II(U) prototypes were included in this order.
  To improve handling, the second UFAG C.I production batch was delivered with increased wingspan, a broader rudder, and an elevator of increased area. Beginning with aircraft 161.91, a small tail fin and an unbalanced rudder became standard. Bomb racks for twelve 12 kg (26 lb) bombs were fitted to all aircraft starting with 161.131. A few machines were powered by the 250 hp Benz (Mar) engine. At least three airmen owed their lives to the Tubus parachute packed in containers in the fuselage floor. Armament consisted of a fixed, synchronized machine gun and an observer's gun mounted on a large, wooden ring. Twin forward-firing guns, tested on aircraft 161.31 in July 1918, were not installed on production machines.
  The UFAG C.I was assigned to most reconnaissance squadrons on the Italian Front, where the type found ready acceptance. It was flown by Fliks 4/K, 5/F, 8/D, 11/F, 15/P, 16/K, 17/K, 19/K, 22/K, 23/K, 24/K, 27/F, 32/D, 35/K, 36/K, 39/P, 44/K, 45/D, 47/F, 49/D, 50/D, 52/K, 53/D, 57/Rb, 58/P, 62/K, 66/K, 67/DS, 71/S, and 102/G. The good maneuverability, slightly better than the Phonix C.I, was especially praised as was the high speed which enabled aircrews to evade enemy fighters. The operational ceiling was about 4000 meters (13,124 ft); at higher altitudes pilots complained of instability and preferred the Phonix C.I for such work. Being a thoroughbred, average pilots found the UFAG C.I difficult to fly at first. Former pilot Philipp Ritter von Vacano remembered the C.I as “a right efficient reconnaissance machine, but with a nasty inclination to sudden and unexpected tail-heaviness while climbing," a tendency that could not be corrected by adjusting the wing alignment. As usual, the rough, unkempt airfields took their toll in fuselage fractures. Fliks 22/K and 67/DS reported in August 1918 that gun rings had torn loose because of wind pressure and vibration or during minor landing mishaps, once causing serious injury.
  On 1 August 1918, a total of 76 UFAG C.I biplanes was at the Front compared to 16 Phonix C.I, and on 20 October the totals were 51 and 6 respectively. It is clear that the UFAG C.I had a greater impact on the air war. Through October 1918 a total of 166 UFAG C.I biplanes, including 40 built by Phonix, had been accepted by the LFT. According to the August 1918 delivery calendar, production was scheduled to end in February 1919 in favor of the Phonix C.I, which was regarded a better aircraft. In a curious reversal, UFAG was scheduled to build and deliver 80 Phonix C.I(U) biplanes beginning in December 1918.
  During the Hungarian revolution in 1919, UFAG C.I output continued. At least 17 machines were flown by the Hungarian Red Airborne Corps. The highest serial recorded was aircraft 161.200 which landed on Austrian territory in 1919. In addition to civil and air mail conversions in 1920, six C.I machines were completed as the "NL Sportplane" by the Neuschloss-Lichtig works, and several C.Is were assigned to the Hungarian Legugyi Hivatal clandestine military establishment.

UFAG C.I 161.01 Specifications
Engine: 200 hp Hiero
Wing: Span Upper 8.92 m (29.26 ft)
Span Lower 8.92 m (29.26 ft)
Chord Upper 1.55 m (5.09 ft)
Chord Lower 1.55 m (5.09 ft)

UFAG C.I 161.02 Specifications
Engine: 230 hp Hiero
General: Maximum Speed 180 km/hr (112 mph)
Empty Weight 680 kg (1499 lb)
Loaded Weight 1060 kg (2337 lb)
Climb: 1000m (3,281 ft) in 2 min 50 sec
3000m (9,843 ft) in 11 min 20 sec

UFAG C.I (First Series 161.03-161.22) Specifications
Engine: 230 hp Hiero
Wing: Span Upper 9.12 m (29.92 ft)
Span Lower 9.12 m (29.92 ft)
Chord Upper 1.60 m (5.25 ft)
Chord Lower 1.60 m (5.25 ft)
Stagger 0.62 m (2.03 ft)
General: Length 7.41 m (24.31 ft)
Height 3.04 m (9.97 ft)
Track 1.80 m (5.91 ft)
Empty Weight 730 kg (1610 lb)
Loaded Weight 1131 kg (2494 lb)
Climb: 1000m (3,281 ft) in 3 min 50 sec
2000m (6,562 ft) in 9 min 5 sec
3000m (9,843 ft) in 16 min 3 sec
4000m (13,124 ft) in 25 min 52 sec

UFAG C.I (Second Series 161.03-161.22) Specifications
Engine: 230 hp Hiero
Wing: Span Upper 9.50 m (31.17 ft)
Span Lower 9.40 m (30.84 ft)
Chord Upper 1.60 m (5.25 ft)
Chord Lower 1.60 m (5.25 ft)
Dihedral Upper 0 deg
Dihedral Lower 1 deg
Sweepback Upper 0 deg
Sweepback Lower 0 deg
Gap 1.54 m (5.05 ft)
Stagger 0.62 m (2.03 ft)
Total Wing Area 26.3 sq m (283 sq ft)
General: Length 7.41 m (24.31 ft)
Height 2.70 m (8.86 ft)
Track 1.90 m (6.23 ft)
Empty Weight 750 kg (1654 lb)
Loaded Weight 1150 kg (2536 lb)
Climb: 1000m (3,281 ft) in 4 min 5 sec
2000m (6,562 ft) in 10 min
3000m (9,843 ft) in 18 min 35 sec
4000m (13,124 ft) in 31 min

WKF 80.01 to 80.03

  References which would correctly identify the WKF 80.01-80.03 prototypes have not been found in LFT records. It has been suggested that these prototype designations were assigned to the first aircraft of the first three production series built by WKF; namely, the Lloyd C.III(WKF) series 43.5, the Lloyd C.IV(WKF) series 44.5, and the Knoller C.II(WKF) series 81, but confirmation is lacking.


WKF 80.04

  The 80.04 two-seat reconnaissance biplane, the first prototype to originate from the WKF design department, was conceived by Ingenieur Alfred Gassner. He chose a fuselage configuration on the basis of wind tunnel tests which had shown a hexagon cross-section to have superior directional stability than a square or round section and less drag than a square one. The robust, plywood-covered fuselage featured a deep "keel" to reduce the aerodynamic interference at the wing-fuselage juncture and facilitate mounting a one-piece lower wing. The generous fuselage depth allowed lowering the engine axis to provide good forward visibility and the installation of a 90cm camera entirely within its profile. To minimize drag, the patented Lloyd veneer-covered wing was adapted by Gassner in the form of a semi-cantilever cellule braced solely by a pair of crossed V-struts attached to the fuselage.
  Construction of the prototype, a private-venture undertaking, began in July and was completed in September 1917, when the prototype arrived at Aspern for evaluation. Power was supplied by a 200 hp Daimler engine. The initial flight tests failed to demonstrate "any noteworthy performance." There is little doubt that redundant weight, often the case with new aircraft, was the reason. In the course of static load testing, directed by Schieferl on 27 October 1917, the 80.04 airframe did not fail until a load factor of 8 was reached, well above the required factor of 5. Even then only a single center-section strut fitting had collapsed. This fully confirmed the strength of the WKF design and the veneer-covered wing cellule developed by Lloyd. Flight performance testing continued in November 1917, after which date the 80.04 prototype disappears from Flars records.

WKF 80.04 Specifications
Engine: 200 hp Daimler
Wing: Span Upper 8.96 m (29.40 ft)
Span Lower 7.82 m (25.66 ft)
Chord Upper 1.90 m (6.23 ft)
Chord Lower 1.60 m (5.25 ft)
Stagger 0.45 m |1.48 ft)
General: Length 7.30 m (23.95 ft)
Height 2.70 m (8.86 ft)
Track 1.80 m (5.91 ft)
Empty Weight 630 kg (1389 lb)
Loaded Weight 1030 kg (2271 lb)

WKF 80.05

  In early September 1917, Gassner began the layout of a triplane fighter using a narrow hexagonal fuselage made sufficiently deep to provide adequate wing gap for aerodynamic efficiency. The wings and tailplanes were veneer-covered and, like the fuselage, were polished to a mirror finish. Four ailerons provided good manoeuvrability. The light but robust undercarriage was not wire-braced, having been intentionally designed to give way in the event of a crash. On 13 September 1917, Flars asked WKF to submit a formal proposal for building four fighter prototypes. The contract, signed on 5 November, provided WKF with funds to support work on the 80.05 triplane and three biplane fighters, numbered 80.06, 80.10, and 80.12.
  The 80.05 triplane, powered by a 200 hp Daimler engine, made its debut at Aspern in October-November 1917 for engineering inspection and flight testing. Flars regarded the structural concept favorably but reported the climb performance lagged behind that of rotary-engined triplane fighters. To reduce the wing loading, wings of greater area were fitted to the prototype in early March 1918. Further information regarding the 80.05 flight evaluation is unavailable. A postwar article stated that the 80.05 prototype was rejected on grounds of insufficient pilot visibility and the arrival of the far-superior WKF 80.06 biplane fighter.
  The 80.05 triplane, reported "assembled" at Fischamend in October 1918, was turned over to the Fischamend industrial works for disposal on 22 May 1919.

WKF 80.05 (Final Version) Specifications
Engine: 200 hp Daimler
Wing: Span Upper 8.00 m (26.25 ft)
Span Middle 7.80 m (25.59 ft)
Span Lower 7.60 m (24.93 ft)
Chord Upper 1.20 m (3.94 ft)
Chord Middle 0.95 m (3.12 ft)
Chord Lower 1.00 m (3.28 ft)
Total Wing Area 22.49 sq m (242 sq ft)
General: Length 6.82 m (22.38 ft)
Height 2.70 m (8.86 ft)
Track 1.70 m (5.58 ft)
Climb: 3000m (9,843 ft) 11 min

WKF 80.06 and 80.06B

  While the 80.05 triplane was nearing completion in October 1917, the design of the elegant WKF 80.06 fighter prototype was well under way. The choice of a suitable airfoil was being investigated in Professor Knoller's wind tunnel. As conceived by Gassner, the hexagonal Fischrumpf (fish fuselage) formed a delicately streamlined shape tapering down to a faired plywood tail empennage. Veneer-covered wings combined with conventional strut and wire bracing gave the cellule great inherent strength. The first flight date is not known, but occurred before the machine guns were installed in February 1918. In the course of performance trials in March, the 80.06, powered by a 200 hp Daimler engine, attained 5000 meters (16,405 ft) in the respectable time of 22 minutes, matching the climb of 200 hp production fighters such as the Albatros D.III(Oef) and Phonix D.II. Refitted with a 230 hp Hiero engine, the 80.06 arrived at Aspern on 30 April 1918, but a severe crash ended the flight program and thwarted the static load tests which had been scheduled for July 1918.
  As a replacement, WKF built a new prototype, designated 80.06B and powered by the new 225 hp Daimler engine. The extensively redesigned airframe featured a longer nose, a larger tail fin, reduced wing gap, and ailerons fitted to both wings. Significantly, Gassner switched to fabric-covered wings as a weight-saving measure and to facilitate production. The WKF 80.06B, in effect a new aircraft, participated in the July 1918 Fighter Evaluation at Aspern in concert with the Hiero-engined WKF 80.10 and 80.12 prototypes. All three fighters were reported as being similar in design but the 80.06B was probably the most advanced. As a result of the excellent performance achieved by the WKF contingent, the design was chosen for production under the designation WKF D.I. Whether the innovative throttle mounted on the control-column (80.06B), praised by the pilots, was used on production aircraft is not known. To iron out last-minute problems, flight testing of the 80.06B continued through August 1918. The prototype was last reported stored in good condition at Aspern on 31 October 1918.

WKF 80.06 Specifications
Engine: 200 hp Daimler
Wing: Span Upper 8.80 m (28.87 ft)
Span Lower 8.40 m (27.56 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.60 m (5.25 ft)
Gap 1.66 m (5.45 ft)
Stagger 0.45 m (1.48 ft)
Total Wing Area 26.4 sq m (284 sq ft)
General: Empty Weight 650 kg (1433 lb)
Loaded Weight 915 kg (2018 lb)

WKF 80.06B Specifications
Engine: 225 hp Daimler
Wing: Total Wing Area 26.2sq. m (282 sq ft)
General: Empty Weight 732 kg (1614 lb)
Loaded Weight 1004 kg (2214 lb)
Climb: 1000m (3,281 ft) in 2 min 30 sec
2000m (6,562 ft) in 5 min 26 sec
3000m (9,843 ft) in 10 min 18 sec
4000m (13,124 ft) in 15 min 30 sec
5000m (16,405 ft) in 25 min 45 sec


WKF 80.10

  For the forthcoming Fighter Evaluation at Aspern on 9-13 July 1918, WKF prepared three prototypes: the 80.06B, 80.10, and 80.12. Very little is known about the last two prototypes, but they differed little from the basic 80.06B layout and were powered by the 230 hp Hiero engine. In the course of the climb competition, the 80.10 was flown by several pilots on 21 May 1918. The 80.10 prototype reached 5000 meters (16,405 ft) in the average time of 21:30 minutes and 6000 meters (19,686 ft) in 28:20 minutes, a very fine showing indeed.
  Among the fighter aces present at Aspern, Hauptmann Maximilian Perini, Oberleutnants Linke-Crawford, Friedrich, Gawel, and von Fiala all took turns evaluating the 80.10. Von Fiala had this to say:
  This aircraft also good. Machine gun installation incomplete. Flight characteristics: maneuvrable, elevator operation symmetrical. Extreme tail-heaviness was not corrected by the company. Aileron connection strut broke owing to vibration, actuation similar to Sopwith. Throttle must be moved from the fuselage wall.
  In the comparative climb tests, the 80.10 was exceeded only by the much lighter (by 77kg - 170lb) Aviatik D.I 338.03. Further data is lacking.

WKF 80.10
Engine: 230 hp Hiero
Wing: Total Wing Area 26.2 sq. m (282 sq ft)
General: Empty Weight 754 kg (1663 lb)
Loaded Weight 1012 kg (2231 lb)
Climb: 1000m (3,281 ft) in 2 min 10 sec
2000m (6,562 ft) in 5 min 15 sec
3000m (9,843 ft) in 9 min 20 sec
4000m (13,124 ft) in 14 min 55 sec
5000m (16,405 ft) in 21 min 15 sec
6000m (19,686 ft) in 28 min 20 sec


WKF 80.12

  The 80.12 fighter prototype was first reported at Aspern on 27 May 1918 and like the 80.10, was powered by a 230 hp Hiero engine. The 80.12, the third fighter entered by WKF in the Fighter Evaluation, was reported even more tail-heavy than the 80.10, so much so that it was impossible to complete the scheduled climb and altitude flights and had to be withdrawn. In July, the 80.12 prototype was used as a test vehicle for developing a suitable top wing radiator in preparation for releasing the design to production under the designation WKF D.I.


WKF D.I Series 85

  WKF had the satisfaction of seeing the WKF D.I series 85 fighter chosen for production, based on the fine showing of the 80.06B and 80.10 prototypes. Initially the LFT command saw fit to hedge its position, having been burned by premature production in the past. Forty-eight WKF D.I fighters had been specified in the 24 August 1918 production program, but implementation remained provisional. The LFT cautioned that
  The test program is being conducted on a priority basis to ascertain whether the WKF D-type is equal to other fighters now in development. If the WKF fighter should demonstrate even an iota less performance than the Fokker D.VII, then WKF will be given a type of equal performance to build.
  In the event this should occur, the LFT proposed the new Pfalz D.XV, which the Germans regarded as equivalent to the Fokker D.VII.
  However, the WKF D.I prevailed. The exact date when the WKF D.I was ordered is unknown, but by mid-September WKF had production approval in hand for 48 D.I fighters, powered by the 230 hp Hiero engine and numbered 85.01 to 85.48. Twenty aircraft were scheduled for delivery in December 1918 and the balance in January 1919.
  Externally the design, supervised by Ingenieur Alfred Gassner, adhered closely to the 80.06B layout with only minor changes. The interplane struts were now canted inward and faired, the tail surfaces enlarged slightly, and the ailerons independently actuated. Internally, the D.I was fitted with full military equipment. Twin synchronized Schwarzlose M 16R machine guns were mounted on the decking within the pilot's reach. The D.I could also operate as a photo-reconnaissance fighter, and space was provided for a 70 or 90 cm camera behind the cockpit. A window at the pilot's feet and a cowl-mounted Sottoscope facilitated terrain recognition. The D.I was provided with an installation rarely seen in WW I fighters: a wireless transmitter and receiver to "receive signals from a director aircraft." As with all late Austro-Hungarian aircraft, a seat parachute was standard equipment.
  Making great progress, WKF appeared to be ahead of schedule. Schieferl reported that the first production fighters were undergoing military acceptance when the war ended. As of 31 October 1918 the resident Flars officer had accepted two completed fighters. Flight testing and assembly work continued and in January 1919, twenty-four D.I fighters were reported stored in good condition at the WKF factory.
  In February 1919, two D.I fighters were flown from Hennersdorf to Wiener-Neustadt for demonstration to a Polish military commission. However, the planned purchase of 20 fighters failed to materialize because during the flight exhibition both aircraft were defective or damaged.

WKF D.I Series 85 Specifications
Engine: 230 hp Hiero
Wing: Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.50 m (4.92 ft)
Stagger 0.48 m (1.57 ft)
General: Length 7.10 m (23.29 ft)
Loaded Weight 1000 kg (2205 lb)
Maximum Speed: 195 km/hr (121 mph)
Climb: 5000m (16,405 ft) in 21 min

Albatros B.I Series 21

  Between 12 August 1914 and 4 February 1915, the LA purchased 31 Albatros biplanes both from Albatros in Johannisthal and directly from the German air service. These were assigned the designations Alb.1 to Alb.31. In February 1915, the two-bay biplanes (Alb.1 to Alb.26 - German B.II) were re-numbered B.I series 21, and the three-bay biplanes (Alb.27 to Alb.31 - German B.I) became B.I series 22. Evidently this caused confusion, and within a short time the LFT decreed that all German-built Albatros biplanes would carry the same series designation, namely B.I 21.01 to 21.31. These biplanes were powered by the 100 hp Mercedes engine and were unarmed. In practice, many Fliks referred to the aircraft by nicknames such as Lump, Elly, Steffel, Loni, or Muzzl which were often prominently displayed on the fuselage.
  Desperately short of aircraft, air service officers went directly to German factories to pick up the aircraft and fly them home. On 9 September 1914, the British journal The Aeroplane reported that eleven Austrian officers flew six Albatros machines from Johannisthal to Vienna in the early days of the war. As they replaced the war-weary Lohner Pfeilfliegers in August-September 1914, the Albatros machines were praised as the best operational two-seaters by virtue of their ruggedness, pleasant flight characteristics, and easy maintenance. The B.I served with Fliks 1, 5, 8, 10, 11, and 13 on the Russian Front until the fall of 1915.

Albatros B.I Series 21 (Three-Bay)
Engine: 100 hp Mercedes
Wing: Span Upper 14.48 m (47.51 ft)
Span Lower 13.30 m (43.63 ft)
Chord Upper 1.70 m (5.58 ft)
Chord Lower 1.50 m (4.92 ft)
General: Length 8.56 m (28.08 ft)
Height 3.15 m (10.33 ft)
Track 2.19 m (7.18 ft)
Empty Weight 752 kg (1658 lb)
Loaded Weight 1197 kg (2639 lb)
Maximum Speed: 100 km/hr (62 mph)
Climb: 2000m (6,562 ft) in 35 min


Phonix 20.01

  The first contract signed on 17 August 1914 by the Oesterreichisch-Ungarische Albatros company (henceforth referred to as Phonix) required the company to deliver a prototype on 1 October 1914 to serve as a test aircraft in preparation for delivering the Albatros B.I(Ph) series 23 production machines. Having served its purpose, the prototype, designated oAlb.01 (changed to 20.01 in February 1915) and powered by a 145 hp Hiero engine, was allocated to Flik 12 in May 1915 as an unarmed reconnaissance machine. After repairs in August 1915, the 20.01 was flown as a trainer by Flek 8 in Wiener-Neustadt. In September 1917, Phonix received information that its first aircraft was stored in damaged condition at Aspern. The LFT accepted the "scrap value" offer of Kr 500, allowing Phonix to preserve the 20.01 for posterity. The 20.01 was presented to the Heeresgeschichtliches Museum in Vienna where it is presently displayed.


Phonix 20.02

  The Phonix 20.02 prototype (w/n 31) was ordered on 23 May 1915 as a test-bed for the experimental 200 hp Hiero inverted V-8 engine that was under development in early 1915. Flars also specified a turret capable of mounting a 7cm cannon. On 27 July 1916, the prototype (possibly the modified 23.32 airframe) arrived at Aspern where subsequent ground trials demonstrated such extreme engine vibration that flight tests and further engine development were cancelled.
  To install the experimental 300 hp Daimler V-12 engine, the 20.02 was returned to Phonix for modification, which began on 8 November 1916 and included fitting new engine bearers, the adoption of a staggered wing cellule and relocating the center-section struts and undercarriage, and removal of armor plating. The static calculations, approval of which was mandatory for flight testing, were submitted on 5 March 1917. The Daimler-engined 20.02 had logged 46.5 hours of flying time by September 1917. In December, preliminary design work was in progress for installing the more powerful 350 hp Daimler V-12 engine, but it is doubtful if this work was completed, for in January 1918 the 20.02 was stored at Aspern where it remained for the duration of the war.


Phonix 20.03

  The Phonix 20.03, powered by a 100 hp Daimler engine, was attached to Flek 2 from November 1915 to December 1915. Further information is lacking.