P.Grosz, G.Haddow, P.Shiemer Austro-Hungarian Army Aircraft of World War One

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

E.Hauke, W.Schroeder, B.Totschinger Die Flugzeuge der k.u.k. Luftfahrtruppe und Seeflieger 1914-1918

50. Flugzeuge der Österreichischen Flugzeugfabrik A.G. (Oeffag) Wiener Neustadt
50.03 Oeffag DD Prototype für C.II Dm 160
50.06 Oeffag DD Prototype für C.II Dm 160
50.07 Oeffag C.II (Motorversuch mit ex 52.82) H 200
52.01 — 52.33 Oeffag C.II Dm 160
52.50 — 52.82 Oeffag C.II Dm 185