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

Otto Pusher Biplane
   Although many machines were built by the Otto firm of Munich before the war, Gustav Otto was plagued by ill health and undertook little work after hostilities commenced, except to build some L.V.G.s under licence. The firm was liquidated late in 1916, and its assets were taken over by B.F.W.

Jane's All The World Aircraft 1913

OTTO. Gustav Otto, Flugmaschinenwerke, Schleissheimer Str. 135, Munich. Started building in 1911. Present max. capacity about 30 machines a year.

   M 1912.
   Biplane.

Length.........feet(m.) ...
Span...........feet(m.) ...
Area......sq. feet(m?.) ...
Weight,
   total....lbs.(kgs.) ...
   useful...lbs.(kgs.) ...
Motor..............h.p. 100 A. G. Otto.
Speed,
   max.....m.p.h.(km.) 69 (110)
   min.....m.p.h.(km.) ...
Endurance.........hrs. 6-8
Number built during 1912 6

Remarks.--All 1912 machines purchased for German Army.

J.Herris Pfalz Aircraft of WWI (A Centennial Perspective on Great War Airplanes 5)

Pfalz-Otto Pusher (Buchner)

   One Pfalz-Otto pusher reached German Southwest Africa in 1914 before the war. Interestingly, this was originally conceived as a publicity stunt! The Berlin department store magnate Rudolf Hertzog and the large Scherl publishing business financed the construction of an Otto pusher to transport diamonds and air mail in German Southwest Africa and fly across the Union of South Africa to Zanzibar and German East Africa. The popular pre-war flyer Bruno Buchner, who had served as a mercenary in the Bulgarian air arm in 1912, was hired as pilot.
   Although long thought to have been built by Pfalz, all indications are that Buchner's pusher was in fact built by Otto and then sent to Pfalz for modification, including installation of a large tropical radiator. After arriving in Swakopmund (combined with his honeymoon voyage), Buchner performed the first flight on 13 May 1914. Buchner flew between Windhuk (Windhoek), Okahandja and Karibib (18-27 May), made several unscheduled landings, and delivered the first colonial air mail. There is no record of Buchner's flying activity in June or July. Owing to the high temperatures, the Pfalz-Otto experienced difficulty in climbing above 300 meters. That and the poor reliability of the 100 hp Rapp engine thwarted the projected flight across Africa, forcing Buchner to proceed by boat.
   Buchner and his aircraft, steaming via Cape Town, arrived in Zanzibar (British protectorate) on 4 August 1914 only to learn that war had been declared; leaving him no choice but to continue on to Dar es Salaam, capital of German East Africa. As stipulated in his employment contract, Buchner joined the German colonial army under the command of General von Lettow-Vorbeck. While on a reconnaissance sortie along the coast, Buchner was wounded by fire from two British gunboats, forcing him to land on the beach and slightly damaging the aircraft.
   The scarcity of fuel precluded long-range flights, but enough was scrounged for short hops to practice bomb dropping with coconuts and crude aerial bombs adapted from 15 cm artillery shells. The military command decided that Buchner's pusher should be fitted with floats to provide support for the light cruiser SMS Konigsberg blockaded by the British navy in the Rufidji (Rufiji) delta. This required extensive modification of wings and fuselage resulting in a virtually new aircraft. A few water starts were successfully performed but the lack of fuel ended further flight activity.


Pfalz-Otto Pusher (Modified)

   The first Pfalz-built aircraft were Otto pushers built under license, Otto being another Bavarian aircraft manufacturer. Only a few Otto pushers were built due to their limited performance. The Otto pushers were powered by 100 hp Rapp engines. Rapp was a Bavarian engine company that was only modestly successful; in 1917 Rapp was bought by investors who brought in new engineering talent and managers and re-cast the company as the Bavarian Motor Works (BMW), which still exists today and makes well-known automobiles.

J.Herris Otto, AGO and BFW Aircraft of WWI (A Centennial Perspective on Great War Airplanes 37)

Otto Pusher Biplane

   Inspired by the Farman configuration, Flugmaschinen Werke Gustav Otto in Munich designed a pusher biplane that proved popular for its unrestricted field of view forward and downward and for its stability and good handling. The Otto pusher gained a reputation for reliability and won a number of pre-war prizes.
   By early 1914 the Otto company claimed to have built 165 aircraft, most of which were the Otto pusher. When the Bavarian army decided to establish an aviation section, the Bavarian-built Otto pushers came immediately to its attention.
   Starting in 1911, the Bavarian army had purchased 9 aircraft (one Wild monoplane, one Albatros biplane, one Bleriot monoplane, five Euler pusher biplanes, and another Euler biplane obtained from a private owner). On 1 Jan. 1912 the Bavarian airship and motor section spun off a Fliegerkommando (flying command) dedicated to evaluating heavier-than-air craft as weapons. This started the Bavarian air service that remained semi-independent from the much larger Prussian air service.
   With establishment of the Fliegerkommando, the Bavarian army soon developed a preference for pusher aircraft. In contrast, the Prussian army had found the LVG B-type tractor biplane to be superior. In alignment with its pusher preference, the Bavarian army obtained 17 Otto and six Euler pusher biplanes to train its airmen. Otto prevailed in army maneuvers and in 1913 the Bavarian army ordered an additional 46 Otto pushers, together with 12 LVG B-types.
   Initially the Otto pushers were made of wood, but by the time the large Bavarian army orders were placed, most of the pushers had a steel-tube airframe. The aircraft retained the characteristic bathtub-shaped crew nacelle. The Bavarians viewed the pusher configuration to have the advantage of unobstructed field of view facilitating observation, bombing, and weapons handing. In addition, takeoff and landing were easier and the crew were not subject to engine oil spray, propeller blast, or exhaust gases. However, pusher disadvantages were items falling overboard could fly into the propeller and positioning of the wings behind the pilot made attitude orientation difficult.
   Otto work numbers 201-206 were the modernized so-called Series 200 airplanes; a new numbering system started at number 201.
Upon outbreak of war the Otto pusher equipped the Bavarian training units and two Bavarian combat units, Feldflieger-Abteihing 1b and later 4b (renamed from Festungs-Flieger-Abteilung Germersheim and taken out of the fortress to the front), both attached to the 6th Army. It is believed these were equipped with both the triple-rudder 1913 model and the single-rudder 1914 model. FFA 1b flew its first combat flight on 10 August, 1914.
   These Otto pushers were powered by the old Argus four-cylinder engines. With these engines the pilots could barely climb above 1200 m (about 4000 feet); this inhibited spotting French troops as the Otto pushers were subject to ground fire from rifles and machine guns. With ground fighting in the Vosges mountains occurred at 800 to 1000 meters, the Ottos were especially vulnerable at only 200 to 400 meters above the ground. Even worse, the planes were fired on by the soldiers from both sides.
   By August 23, 1914, the Bavarian air service had 19 Otto pushers (with 100 hp Mercedes or Argus engines), 24 LVG B-types, and two unknown types. The Otto pushers were already obsolete, yet FFA 1b had to wait until December before the Ottos were replaced by Albatros and LVG B-types. The LVGs were built by both LVG and Otto under license.
   On April 16, 1915 the Otto pusher inventory was five at FFA 4b, four at Schleissheim, and one at Flugpark 6b. The first armed C-type replacements started to arrive at 6th Army in May 1915.
   Having early developed a preference for tractor aircraft, the Prussian air service, with one exception, did not use the Otto pusher. (During the beginning of BAO (Brieftaubenabteilung Ostende) one Bavarian crew seconded to it flew their Otto pusher biplane.) However, the German Navy, chronically short of aircraft, ordered a number of Otto pusher seaplanes. The Johannisthal naval volunteer pilot school also operated a number of Otto (Ago) pusher landplanes. The naval aircraft were supplied by the AGO Flugzeug Werke, Otto's license company in Berlin.
   Note: From 1914 to end of 1916 there were no Flieger-Abteilungs, despite the term being sometimes used.There were only Feldflieger-Abteilungen (FFA's) and Artiellerieflieger-Abteilungen (AFA's).


Otto 1914 Pusher Specifications
   Source Flight, 14 August 1914. P.862 Flugsport, 1914
   Span, top 14.8 m 14.800 m
   Span, bottom 9.5 m 9.500 m
   Length 10.5 m 10.500 m
   Height - 3.600 m
   Chord 1.8 m 1.800 m
   Gap - 1.500 m
   Track - 2.100 m
   Wing Area, m2 40 -
   Speed in kph 110 -


Ago School Biplane

   As a subsidiary of the Otto company, it is not surprising that AGO's first production aircraft type was a copy of the first successful Otto type, the biplane pusher trainer powered by a 100 hp Argus engine.
   As did Otto, AGO started producing the early version of the Otto pusher trainer with three rudders and later changed to producing the pusher trainer with the simplified tail with one rudder and monoplane tailplane.

Журнал Flight

Flight, August 14, 1914.

AEROPLANE TYPES.
THE OTTO MILITARY BIPLANE.

   THE Otto military biplane (type 1913), although somewhat on the lines of the Henry Farman military machines, actually differs from this type in many respects. First and foremost, it is constructed practically throughout of steel. Some considerable difference will also be found in the disposition of the engine and nacelle, the former being higher and the latter lower than obtains in Farman practice. Each of the main planes is built up on two spars, the front one of which is close to the leading edge, whilst the rear spar is placed some distance from the trailing edge. Both planes are given a slight dihedral angle and are attached to small, fixed, central pannels or sections. The upper plane has a greater span than the lower one, and large ailerons are fitted to the upper plane extensions only. Six pairs of steel struts separate the top and lower planes, and two pairs of triangular outriggers extend rearwards from the rear spars and carry the tail. The latter consists of a fixed stabilising plane, 3.2 sq. m. area, mounted on the top outriggers, and having two elevator flaps hinged to the trailing edge. Between the elevators is a vertical rudder hinged to the last strut joining the top and bottom outriggers. The nacelle, which is well streamlined, extends forward of, and below the lower plane, the pilot being seated in front with the passenger behind him; the front portion of the nacelle slopes upwards, forming a protection from the wind for the pilot. At the rear of the nacelle is a strong superstructure, carrying the engine high up, midway between the main planes. In front of the engine is the radiator, and above is the fuel tank. A portion of the trailing edges of the top and bottom planes is cut away to provide clearance for the propeller, which is 27 m. in diameter. The engine is a 6-cyl. 100 h.p. Argus, a type that has given very satisfactory results in Germany. The landing chassis is both strong and simple, consisting of two pairs of steel struts inclined outwards and forwards from the nacelle attached to two short skids, secured to which, by means of rubber shock-absorbers in the usual way, is a tubular steel axle carrying a pair of wheels. The control is of the usual Farman type, consisting of a central universally jointed lever actuating the ailerons by a side to side movement and the elevator by a to-and-fro movement; a horizontal foot-bar operates the rudder. The principal dimensions of this machine are :- Span, 14.8 m. (top), 9.5 m. (bottom); chord, 1.8 m.; supporting area, 40 sq. m.; overall length, 10.5 m.; speed, 110 k.p.h.
"VEE JAY."


Flight, September 18, 1914.

AIRCRAFT "MADE IN GERMANY"
WHICH MAY BE EMPLOYED AGAINST THE ALLIES.

27. The Otto Biplane
   is one of the comparatively few propeller biplanes in use in Germany. It is somewhat reminiscent of the Henry Farman biplane, the upper main plane being of considerably greater span than the lower one. The nacelle, however, is of quite a different type from that of the Henry Farman, both as regards its shape and position. The upper longerons of the nacelle are attached to the spars of the lower main plane, and both upper and lower longerons taper to a point in the nose, whilst gradually flattening out towards the rear. To the tips of the upper main planes are hinged ailerons which are of greater chord at their tip than at the root, in order, no doubt, to render them more effective. The engine - a 100 h.p. Mercedes - is mounted a considerable distance above the lower plane, and drives a propeller situated behind the main planes, the trailing edges of which have been cut away in the centre to provide the necessary clearing. The tail planes are carried on an outrigger of steel tubes, and consist of a fixed stabilising plane, hinged to the trailing edge of which is the divided elevator, and of a partly balanced rudder. It will be noticed that, as in the Henry Farman, no vertical tail fin is fitted.