O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

Aviatik C I and C III

   One of the first products of the German aircraft industry to become well known to the public during the First World War was that of the Automobil und Aviatik A G . After the Taube had been well publicised by the daily Press, the next name brought to popular notice was that of Aviatik. It is open to doubt whether all aircraft referred to by the Press as Aviatiks were indeed such. The firm was well known in aviation circles before the war, and after hostilities opened many of its B I and B II types were in service on unarmed reconnaissance duties.
   The first Aviatik type to see large-scale production was the C I, which came out in early 1915, powered with the 160 h.p. Mercedes D III engine and armed with a defensive machine-gun for the observer. The Aviatik was unique among German operational tractor C class two-seaters in having the pilot sitting in the rear cockpit and the observer forward, with his machine-gun clipped on a sliding mounting fitted on a rail at either side of the cockpit. The gun was transferred from one side of the cockpit to the other, as occasion demanded, and was secured with a quick-release mechanism. This seating arrangement was the same as that used by the British in their B.E. 2c (and its variants), and suffered the same shortcomings, i.e. restricted field of fire when it was necessary to use the machinegun, and an equally restricted view when making reconnaissance observations. Later, an effort was made to rectify this by reversing the seating arrangements, but by that time superior designs were coming from the Albatros, L.V.G. and Rumpler factories.
   There was nothing spectacular or unique about the construction of the C I. The fuselage was a conventional box-girder structure of four spruce and with a rounded top decking of light stringers, tapered to a vertical knife-edge aft. Forward, the longerons converged and terminated in a sheet steel end plate, fretted with lightening holes. This, and the first two formers, supported the ash engine bearers, which were additionally braced with steel tubes.
   Curved aluminium panels surrounded the 160 h.p. Mercedes D III engine at the nose and the forward top decking, leaving the cylinder block exposed. The sides and underneath of the nose, as far aft as the leading-edge of the lower wings, were covered with flat aluminium sheet, the remainder of the fuselage being fabric-covered. On the first C Is the radiators were located on the fuselage sides, but an improved Teeves and Braun radiator was soon substituted and mounted on the front centre-section struts, just below the leading edge of the top wing. Forward view was also materially obstructed by the chimney-type manifold exhausting up and over the top wing.
   The rectangular-shaped fabric-covered wings were of all-wood construction except for the steel-tube compression struts. The main spars were made in two halves (of spruce), spindled out to form a U-section and then joined together with hardwood tongues to form hollow box-spars. The ribs themselves were of poplar or lime (linden), and the trailing edge of wire, with the characteristic scalloped outline. Plain, unbalanced, parallel-chord ailerons were hinged direct to the rear spar at the upper wingtips. The centre-section cabane, of inverted trestle type, and all interplane struts were of streamlined steel tube and braced with stranded cables. The bracing of the inboard bay was unusual, in that the front flying wire was anchored to the rear spar junction with the fuselage and the rear flying wire was anchored to the front spar junction. The landing wires ran from the lower end of the inner struts and were terminally anchored to the lop longeron instead of running to the apex of the centre-section trestle, as was usual. This arrangement was doubtless to facilitate operation of the defensive gun on the tubular rails on the sides of the front cockpit.
   A normal vee-type undercarriage was fitted, the actual struts being joined by a short horizontal tube at the apex which served as an anchorage for the rubber cord shock absorbers. An elliptical tube spreader-bar joined the vees in front of the axle and a wire strainer connected them behind the axle. Stranded cables cross braced the undercarriage between the front legs.
   With the exception of the tailplane ribs, which were of wood, the whole of the tail surfaces were of light-gauge steel tube; the tailplane, combined with the split elevators, being of distinctive kidney shape. The comma-shaped rudder was the only control surface to be balanced, and was hinged to a long narrow triangular I'm which was braced to the tailplane with a light steel strut. Underneath, the tailplane was braced to the fuselage with two light struts on each side.
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   Aviatiks were used by the Fl. Abt. units for reconnaissance, and on occasion they were operated in nights of anything from three t o six aircraft, solely as armed escort t o unarmed reconnaissance machines. The destruction of an Aviatik on 7th November 1915 was instrumental in the award of the Victoria Cross t o 2nd Lt. G. S. M. Insall of No. 11 Sqdn. R . F . C , who, flying a Vickers Gunbus, forced down the Aviatik. Its destruction was completed by his dropping a bomb on it.

TECHNICAL DATA
   Description: Two-seat reconnaissance and escort.
   Manufacturers:
   Automobil und Aviatik A.G. (Av.).
   Hannoversche Waggonfabrik A.G. (Han.).
   Power Plant: One 160 h.p. Mercedes D III 6 cylinder in-line water-cooled engine.
   Dimensions: Span, 12 5 m. (41 ft. 0 1/4 in.), C I; 118 m. (38 ft. 5 5/8 in.), C III. Length, 7.925 m. (26 ft. 0 in.), C I; 8.08 m. (26 ft. 6 1/8 in.), C III. Height, 2.95 m. (9 ft. 8 1/8 in.), C I; 2.95 m. (9 ft. 8 1/8 in.), C III. Wing area, 43 sq.m. (465.4 sq.ft.), C I; 35 sq.m. (378 sq.ft.), C III.
   Weights: Empty, 750 kg. (1,650 lb.), C I; 980 kg. (2,156 lb.), C III. Loaded, 1,242 kg. (2,732 lb.), C I; 1,340 kg. (2,948 lb.), C III.
   Performance: Maximum speed, 142 km.hr. (88.75 m.p.h.), C I; 160 km.hr. (100 m.p.h.), C III. Initial climb, 1,000 m. (3,280 ft.) in 12 min., C I; 1,000 m. (3,280 ft.) in 7 min., C III. Ceiling, 3,500 m. (11,480 ft.), C I; 4,500 m. (14,760 ft.) in 55 min., C III. Duration 3 hr.
   Armament: One Parabellum machine-gun for observer mounted on rails on either side of front cockpit, the gun transferred as necessary. Later, on the C III, two guns were mounted, one on either rail.

J.Herris Aviatik Aircraft of WWI (A Centennial Perspective on Great War Airplanes 10)

Aviatik C.I

   The Aviatik C.I (company designation P25) was an armed development of the earlier Aviatik Type P15. It looked very similar to its predecessor and the airframe remained conventional wood, wire, and fabric. To improve performance while carrying the additional weight of machine guns, Aviatik engineers slightly enlarged the airframe and installed a more-powerful 160 hp Mercedes D.III engine, then just entering quantity production. Machine-gun rails were fitted to both sides of the front cockpit and the wing bracing wires were moved to provide a greater forward field of fire for the guns. In mid-1915 Idflieg had not yet determined which layout - the machine-gun at the front or the rear - would provide the best all-round defense. To determine the superior setup, Idflieg ordered Aviatik C.I machines with the machine-gun armament placed in the front location, whereas Albatros C.I and LVG C.I aircraft were armed with a rear turret. No synchronized gun for the pilot was installed.
   Airmen accustomed to the stable, sluggish B-types found that greater flying skill was required to handle the increased maneuverability and livelier control response of the new, more powerful C-types. However, improved performance and maneuverability were demanded by the increasing level of air combat and aircrews had to adjust. In mid-1915 the intensity and frequency of air combat were still relatively low, so the forward machine-gun location was not viewed as a particular disadvantage. Feld-Flieger Abteilung 6b reported that the field of fire from the front cockpit was 'medium good' and that successful attack or defense was primarily a function of the pilot's skill in air combat maneuvers. The Aviatik C.I arrived at the front in mid-1915 and served in quantity throughout 1916 before being replaced at the front in the first half of 1917.
   Ironically, in April 1917, Idflieg ordered 50 Aviatik C.I biplanes fitted with a rotating turret behind the pilot for gunnery training. This is difficult to understand because C.I production had ceased in 1916 and Aviatik was fully engaged in production of DFW C.V(Av) biplanes at the time. Under the circumstances, this production program was accorded low priority; the first aircraft was not delivered until October 1917 and the type-test was not completed until January 1918. Aviatik records show that Leipzig-Heiterblick delivered one prototype and 40 production trainers powered by the 150-hp Benz Bz.III engine and Bork delivered ten C.I trainers powered by the 160-hp Mercedes D.III engine.


Aviatik C.I(Han)

   When the Hannoversche Waggonfabrik began aircraft production in 1915, the designation of the license-built Aviatik C.I originally assigned by Idflieg was Hannover C.I. However, this confusing designation was soon changed to Aviatik C.I(Han). The first example, C.1951/15 (w/n 1), was type-tested in February 1916. Hannover delivered a total of 146 Aviatik C.I(Han) aircraft to the Fliegertruppe.


Aviatik C.Ia

   According to Aviatik, the Aviatik C.Ia biplane 'brought about several experimental improvements that would come into their full importance with the Aviatik C.III.' Aviatik engineers designed the C.Ia biplane to 'achieve greater airspeed at the expense of the useful load capacity.' As such, the C.Ia, powered by a 160 hp Mercedes D.III engine, represented the first prototype for the Aviatik C.III, although the production C.III airframe would be further refined. The C.Ia prototype, ordered in April 1916 - the first in an order of 25 Aviatik C.III reconnaissance biplanes - probably made its appearance in May-June 1916. An undated crash photograph taken at FEA 3 shows that the aircraft was designated C.Ia 1750/16.


The specifications of the production Aviatik C-types are given in one table for ease of comparison.
Aviatik C-Type Specifications
Aviatik C.I Aviatik C.II Aviatik C.III
Engine: 150 hp Benz Bz.III 160 hp Mercedes D.III 200 hp Benz IV 160 hp Mercedes D.III
Span, Upper: 12.5 m (41.0 ft.) 11.71 m (38.4 ft.) 11.8 m (38.7 ft.)
Span, Lower: 10.75 m (35.3 ft.) 11.71 m (38.4 ft.) 10.2 m (33.5 ft.)
Chord, Upper: 1.88 m (6.17 ft.) 1.70 m (5.58 ft.) 1.70 m (5.58 ft.)
Chord, Lower: 1.88 m (6.17 ft.) 1.70 m (5.58 ft.) 1.70 m (5.58 ft.)
Length: 7.91 m (25.95 ft.) 6.95 m (22.8 ft.) 8.08 m (26.5 ft.)
Track: 1.94m (6.36 ft.) - 1.95 m (6.40 ft.)
Gap: 2.0 m (6.56 ft.) 1.80 m(5.91 ft.) 1.80 m (5.91 ft.)
Wing Area: 43 sq. m. (463 sq. ft.) 37.9 sq. m. (408 sq. ft.) 35.0 sq. m. (377 sq. ft.)
Empty Weight: 745 kg. (1,642 lb.) 916 kg. (2,019 lb.) 895 kg. (1,973 lb.)
Loaded Weight: 1,245 kg. (2,745 lb.) 1,509 kg. (3,327 lb.) 1,220 kg. (2,690 lb.)
Maximum Speed: 120 km/h (74.6 mph) 155 km/h (96.3 mph) 155 km/h (96.3 mph)
Cruise Speed: - - 140 km/h (87 mph)
Climb to 1,000 m: 5 minutes - 6.5 minutes
Climb to 2,000 m: 16 minutes - 16 minutes
Climb to 3,000 m: 33 minutes - 31 minutes
Climb to 4,500 m: - - 55 minutes
Service Ceiling: - - 4,500 m
Duration: 3 hours - Range: 480 km
Armament: 1-2 flexible machine guns 1-2 flexible machine guns 1-2 flexible machine guns
Note: The C.III had 1 degree of dihedral on both upper and lower wings.


Aviatik C.I Production Orders
Date Qty Serial Numbers
Unknown 3 C.28-30/15
April 1915 6 C.68-73/15
May 1915 12 C.178-189/15
June 1915 18 C.375-392/15
Sep.1915 36 C.814-849/15
Oct.1915 50 C.1400-1449/15
Nov. 1915 75 C.3500-3574/15
Dec.1915 50 C.4463-4512/15
Feb.1916 25 C.212-236/16
March 1916 25 C.815-839/16
April 1916 50 C.1700-1749/16
April 1916 1 C.1750/16 - Aviatik C.Ia
April 1917 50 C.4250-4299/17 (Note 1)
April 1917 1 Note 2

Aviatik C.I(Han)
Sep. 1915 24 C.1951-1974/15
March 1916 50 C.600-649/16
June 1916 24 C.2100-2123/16
July 1916 24 C.2764-2787/16
Sep.1916 24 C.3367-3390/16
Total Ordered 548
Note 1: Ordered as trainers, pilot in front. Note 2: According to Aviatik records, one additional C.I prototype trainer was delivered

C.Owers, J.Herris Hannover Aircraft of WWI (A Centennial Perspective on Great War Airplanes 46)

Hannover Aircraft Orders & Production, 1915-1919
Known Serials Quantity Comments
Aviatik C.I(Han)
1951-1974/15 24 1951/15 type test February 1916
600-649/16 50
2100-2123/16 24 2114/16 type test August 1916
2764-2787/16 24
3367-3390/16 24 Total 146 built

M.Dusing German Aviation Industry in WWI. Volume 1 (A Centennial Perspective on Great War Airplanes 84)

Automobil und Aviatik A.-G., Leipzig-Heiterblick (Av)

Aircraft Development:

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  During the war, Automobil- u. Aviatik A.G. achieved successes that testified to a skilful ability to adapt to the increased and constantly growing demands placed on military aircraft by the army administration in terms of flight characteristics and combat capability.
  In 1914/15, the first C airplanes were built. The Av C.I with a 160 hp Mercedes engine and frontal radiator reached a top speed of 142 kph. A striking feature was that the observer sat in front of the pilot. This resulted in a better field of fire.
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Журнал Flight

Flight, February 15, 1917.

THE AVIATIK BIPLANE - 1916 TYPE.

   UNDER present conditions it is naturally a matter of considerable difficulty to obtain detailed information concerning enemy aeroplanes. Even when one of these is brought down intact behind our lines - which is not, unfortunately, very frequently the case, as the greater part of the fights in the air take place beyond the lines, and therefore the enemy machines, when brought down, generally hit behind their own lines - some considerable time must necessarily elapse before our own and the French military authorities have finished their examinations and the machines become available for other inspection. We have, however, been fortunate enough, in spite of the difficulties indicated, to obtain facilities for examining several of the enemy planes from time to time, and have in this way been in a position to publish detailed descriptions illustrated by photographs and sketches, as well as scale drawings, of such German machines as the Albatros reconnaissance biplane, the Fokker monoplane, the Albatros fighting biplane and the L.V.G. fighting biplane. The description of the Aviatik biplane - for the photos, of which we are indebted to our contemporary L'Aerophile - in the present issue brings our list practically up to date -at any rate up to the latter part of 1916 - and during the present year we shall endeavour to keep our readers as well informed regarding the German 1917 types as we have done with the 1916 types in the year just gone by.
   In the 1916 type Aviatik biplane the body is of the wood girder variety, covered with fabric at the rear, while from the nose to a point behind the engine, the covering is aluminium. In section, the body is rectangular, and differs from earlier types in that the upper longerons, or rails, are no longer parallel to the line of thrust as they were, but slope down gradually towards the stern post and somewhat abruptly towards the nose of the fuselage.
   Diagonal wire bracing is employed, and the wiring plates at the point where the struts abut on the rails are shown in one of our sketches. This wiring plate, for which, by the way, the Aviatik firm hold a patent consists, as will be seen, of a single sheet steel clip totally surrounding the rail and bolted together where its two ends meet, so as to grip the rail. No strut socket is employed, the strut being prevented from slipping by the simple means of punching the metal of the clip upwards in the shape of four small triangles, which project into the end of the strut. In front the four rails converge but do not quite meet, the extreme nose of the body being formed by a steel capping plate having lightening holes cut in it. On this end plate, and two more further back, rest the two longitudinal ash engine bearers, further rigidity being obtained by bracing the engine bed with steel tubes from the body rails.
   Immediately behind the engine is the gunner's cockpit, while still further towards the rear is the pilot's seat. This arrangement is rather different from that usually found in German machines, where generally the pilot is in front, as, for instance, in the Albatros fighting biplane and in the L.V.G. It would appear that the gunner's movements must be somewhat hampered, enclosed as he is between struts, wings, &c. Along each side of the body runs a tubular rail mounted on brackets on the side of the body. The gun mounting itself is free to slide along these rails, and can be locked in position by means of a cam operated by a handle as shown in the sketches. In order to compensate for the difference in distance according to whether the gun is near the centre or at the ends of the rail, the gunner's cockpit is of rectangular form, thus allowing him a certain amount of movement forward and backward.
   On each side of the gunner is a large petrol tank each containing about 24 gallons of petrol. Mounted on the front struts supporting the upper plane is a small service tank to which petrol is fed from the two main tanks by means of a small propeller-driven pump, a hand-pump being provided in the pilot's cockpit for emergencies. A fourth small cylindrical tank is mounted underneath the motor, an air pressure being maintained in it by a small pump driven off the cam shaft of the engine. Needless to say, such an arrangement of tanks necessitates a very complicating feed and pressure arrangement, and provision has been made for running the engine on the contents of one of the tanks in case the others have been pierced by projectiles. Between them the tanks have a capacity of 55 gallons of petrol.
   As already mentioned, the engine - a Mercedes of about 170 h.p. - is mounted on ash bearers in the nose of the body. A large portion of the cylinders projects through the covering, and must hamper the gunner's view very considerably, especially as the exhaust collector rises up above the top plane. The radiator is no longer, as in the earlier types, mounted on the sides of the body, but supported on brackets on the front struts of the cabane, yet not let into the top plane as is the case with that of the L.V.G. biplane. The oil tank, which has a capacity of about 4 1/2 gallons, is placed above the reserve petrol tank, on the left side of the engine. In conformity with general modern German practice the under-carriage is of the simple Vee type; differing, however, from the majority of other makes in that the front and rear chassis struts do not quite meet at the bottom, where they are attached to a short horizontal tube which serves as an anchorage for the shock absorbers. The latter consist of rubber rings, one strand of which is taken below the axle instead of above it in order to form a buffer between the axle and the elliptical tube connecting the apices of the two Vees of the under-carriage. The two front chassis struts are cross-braced by means of cables, eyebolts into which the cables are spliced doing service as terminals and strainers at the same time by passing through the lower horizontal - or skid - portion of the chassis. In the rear bay of the under-carriage bracing is effected by a single cable running across horizontally from the strut on one side to the corresponding strut on the other, the terminals being eyebolts similar to those used in the front bay.
   The controls are of the usual type, consisting of a wheel mounted on the top of a vertical tube, the lower end of which is secured to a transverse rocking shaft. A short length of chain passes over a sprocket on the wheel axle, and is connected to the cables, leading to the ailerons. The elevator cables pass, the upper one direct to the upper crank lever on the elevator, and the other over a pulley a short distance in front of the control column. A foot bar with heel rests operates the rudder.
   In plan the main planes are of the usual Aviatik type, with the exception, perhaps, that the backward slope is less pronounced than in older types. The wings are not staggered, but both are given a slight dihedral angle, whereas in the older model the lower wing had a pronounced dihedral, while the upper wing was straight. The angle of incidence, which is constant from root to tip, is about 4°, a fact which, coupled with the section employed, appears to indicate a considerable lift but no very great speed. Constructionally the wings are chiefly remarkable on account of the placing of the back spar, which is, it will be seen, placed very far forward in the section. The spars are spruce, with the exception of the upper back spar, which is of ash. They are of the box section, the two halves being spindled out and glued together, with the usual hardwood tongues. The ribs are made throughout of poplar, and the webs lightened as shown in one of our sketches. Compression struts in the form of steel tubes are placed at intervals, those occurring at the points of attachment of inter-plane struts to spars being secured to the strut fitting, while those placed between struts have their own fitting as indicated in the accompanying sketches. The attachment of the spars to the body forms the subject of another illustration. A short steel tube runs across and inside the fuselage, and is sweated into a collar, which, in turn, is secured to a clip passing under the bottom body rails. Into the outer end of this collar is sweated or welded a short eyebolt that passes between the forked ends of the fitting on the root of the spar. An L-shaped pin is passed through a groove in the inner rib and through the three holes, thus locking the spar to the body. This pin is prevented from slipping out by the small cover over the slot in the inner rib, which, when closed down, locks the pin in position. A similar arrangement is employed for attaching the upper wings to the four-legged cabane. The interplane struts are stream-line steel tubes filled with wood, a practice adhered to practically throughout this machine. The strut fitting is shown in a sketch which does not, we think, need any explanation.
   The cross bracing, which is in the form of stranded cables, is somewhat peculiar, especially in the inner bay. Here the lift cables are crosses, that is to say, the one runs from the top of the front inter-plane strut to the attachment of the rear bottom spar to the body, and the other from the top of the rear strut to the root of the front lower spar. This practice appears to be generally favoured among German aeroplane constructors, as it is incorporated also in the Albatroses and L.V.G.'s. It has, of course, the advantage of bracing the wings in a fore-and-aft direction, but must, it would seem, put a considerable stress on the inner compression strut inside the upper wing. The landing cables in the inner bay, instead of being attached to the top of the cabane, are anchored to the top body rails, as shown in the front elevation, the object probably being to provide a free movement for the machine gun.
   As regards the shape of the tail planes, this will be clear from the scale drawings, but a few words concerning their construction may be of interest. With the exception of the ribs of the fixed tail plane the control organs are made of steel throughout. The fixed stabilising plane rests on the upper body rails, and as these, as already mentioned, are not horizontal, the tail is set at a small angle of incidence in relation to the line of thrust. Underneath it is braced by four short steel tubes to the bottom body rails, and on top by two tubes running to the vertical fin.
   As regards the armament of the Aviatik, there are, in addition to the two gun mountings already referred to, two bomb tubes, one on each side of the pilot and slightly ahead of him. The bombs, of which sizes up to about 8 1/2 ins. can be accommodated, are released from the gunner's seat by means of Bowden cables.


Flight, September 11, 1919.

AVIATIK "MILESTONES"

   OF the German aircraft firms which were in existence before the War, one of the best known and most important was the Aviatik (Automobil u. Aviatik A.G.), whose works were originally at Mulhausen, Alsace. Quite early in the War, however, the proximity of the works to the front made it necessary to transfer them to a safer locality. This was hurriedly done, under cover of darkness it is alleged, and works were established at Freiburg im Breisgau. The demands for output soon rendered these works too small, and a large factory was established at Leipzig-Heiterblick, which is at the present time the main Aviatik factory. Work was commenced at this factory in 1916, and in addition the Grade works at Bork i. d. Mark, near Berlin, were purchased by the Aviatik firm, who enlarged them considerably and established a flying school there. The Aviatik firm intends to remain in the aircraft industry after the War, and in view of this fact, as well as on account of the amount of work done by this firm during the War, a few brief notes on the various Aviatik types, based on an article published in Flugsport, may not be without interest.

The Aviatik, Type C I
   This machine, which was built during 1914-1915, had a 160 h.p. Mercedes engine, and the radiator mounted on the front struts of the cabane. The gunner occupied the front seat, two straight gun rails being mounted on the sides of the fuselage. The machine had a speed of 142 km./hour.

The Aviatik, Type C III
   was built in 1916, and also had a 160 h.p. Mercedes engine. It was designed to meet the demand for better performance and although the engine remained the same, the speed of this type was increased from 142 to 160 km./hour. This was accomplished mainly by a general "cleaning up," as placing the radiator in the top plane, giving the body a better streamline shape, and last, but not least, by employing a different wing section.