The Zeppelin-Staaken VGO.III was a heavy bomber built in Germany in 1916 and which saw limited service during World War I.Gray & Thetford 1992, p.582 Although only one example was built, it served as a prototype for further ("giant aircraft") by Zeppelin-Staaken. Its "VGO" designation was assigned because the aircraft was constructed by Versuchsbau Gotha-Ost, a division of Gothaer Waggonfabrik. It was developed from the VGO.I that had been purchased by the Imperial German Navy, but the VGO.III was purchased by the Army instead. It was the first six-engined aircraft in the world.Szigeti 2007, p.13
Design The VGO.III was based on its VGO.I and VGO.II predecessors. It shared their wing design,Haddow & Grosz 1988, p.226 and, with some modifications, their fuselage design as well.Haddow & Grosz 1988, p.227 Its tail unit was similar to that of the VGO.II. Overall, it was a four-bay, equal-span biplane with slightly negative wing stagger.Haddow & Grosz 1988, p.213 Of mostly conventional configuration it diverged most noticeably from the designs of the day not only by its size, but by its biplane horizontal stabilisers, its two fins, and its tricycle undercarriage.Herris 2020, p.15 Its two pilots sat in an open cockpit.Haddow & Grosz 1988, p.212
Its most innovative feature was its engine installation. The VGO.I and VGO.II had been plagued by being underpowered.Gray & Thetford 1992, p.583 The VGO.III attempted to solve this problem by doubling the number of engines from three to six, and by replacing their troublesome Maybach HS engines for more proven Mercedes D.III units.Herris 2020, p.64 In each location where its predecessors had mounted an engine, the VGO.III mounted a pair. The power of each pair was combined by a gearbox and clutch to drive a single propeller, meaning that if one of the pair failed, it could be disengaged so that the surviving engine could continue to power the propeller.
One pair of engines was mounted in the nose, driving a tractor propeller, and the other two pairs were mounted in nacelles in the interplane gap and drove pusher propellers. These nacelles were large enough to accommodate a mechanic, who could make his way into them in flight (a requirement of the specification). The fuselage included a bomb bay large enough to carry a bomb. As defensive armament, the VGO.III carried two machine guns in the fuselage, one firing upward and the other downward, plus a machine gun in the front of each engine nacelle.Haddow & Grosz 1988, p.221
Also unusual for the time was the inclusion of a radio set, comprising a Siemens-Schuckert transmitter and Telefunken receiver.Haddow & Grosz 1988, p.228Herris 2020, p.65
Development Construction of the VGO.III began in October 1915,Haddow & Grosz 1988, p.225 and although the date of its first flight is not now known, it took place between 29 May and 4 June 1916. It was accepted into Army service on 28 August and assigned the Idflieg serial R.10/15.Haddow & Grosz 1988, p.227
During test-flying, aerodynamic balances for the ailerons were installed on the interplane struts to lighten control loads, but these proved ineffective and were later removed.Herris 2020, p.64–65
Operational history The VGO.III was assigned to Rfa 500 (, "giant aeroplane unit") and flew around seven combat missions, targeting railway facilities, troop encampments, and depots around Riga. Its final mission, a training flight on 24 January 1917, ended in disaster.Haddow & Grosz 1988, p.230 As the VGO.III landed at Auce, it was caught in a sudden downdraft which caused it to land short. The forward undercarriage struck an obstacle, and caused the aircraft to break up. Fuel from ruptured lines sprayed onto the nose exhaust stacks, causing the wreck to catch fire. Five crew members were killed in the first fatal accident involving an R-plane.
Operators Imperial German Army Air Service Rfa 500
Specifications
Notes References
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