This aircraft was mainly used for night bombing raids on London. The plane had enclosed crew cabins and the engines could be worked on during flight.
The Zeppelin-Staaken R.VI was a four-engined German biplane strategic bomber of World War I, and the only so-called Riesenflugzeug ("giant aircraft") design built in any quantity. The R.VI was the most numerous of the R-bombers built by Germany, and also one of the first closed-cockpit military aircraft (but the first was Russian aircraft Sikorsky Ilya Muromets). The bomber was reputedly the largest wooden aircraft ever built until the advent of the Hughes H-4 Hercules built by Howard Hughes, its wingspan of 138 feet 5.5 inches (42.20 m) nearly equaling that of the World War II B-29 Superfortress.
In September 1914, at the start of World War I, Ferdinand von Zeppelin visualised the concept of a Riesenflugzeug (R) bomber, to be larger than the Gotha G. Using engineers from the Robert Bosch GmbH, he created the Versuchsbau Gotha-Ost (VGO) consortium in a rented hangar at the Gotha factory. Alexander Baumann became his chief engineer, although later the team included other noted engineers including Zeppelin's associate Claudius Dornier, Hugo Junkers and Baumann's protogé Adolph Rohrbach. All of these Zeppelin-Staaken Riesenflugzeug designs used some variation of push-pull configuration in the setup, orientation and placement of their powerplants.
The first Riesenflugzeug built was the VGO.I flying in April 1915, using three Maybach Zeppelin engines; two pusher and one tractor. This was built for the German Navy and served on the Eastern Front Later modified with two extra engines, it crashed during tests at Staaken. A similar machine, the VGO.II was also used on the Eastern Front.
Baumann was an early expert in light-weight construction techniques and placed the four engines in nacelles mounted between the upper and lower wing decks to distribute the loads to save weight in the wing spars.
The next aircraft, the VGO.III was a six-engined design The 160 hp Maybach engines were paired to drive the three propellers. It served with Rfa 500.
In 1916 VGO moved to the Berlin suburb of Staaken, to take advantage of the vast Zeppelin sheds there. The successor to the VGO III became the Staaken R.IV, the only "one-off" Zeppelin-Staaken R-type to survive World War I, powered by six Mercedes D.III and Benz Bz.IV engines that powered three propellers, a tractor configuration system in the nose, and two pusher-mount on the wings. By the autumn of 1916, Staaken was completing its R.V, R.VI, and R.VII versions of the same design, and Idflieg selected the R.VI for series production over the 6-engined R.IV and other R-plane designs, primarily those of Siemens-Schuckertwerke AG.
With four engines in a tandem push-pull arrangement, it required none of the complex gearboxes of other R-types. Each bomber cost 557,000 marks and required the support of a 50-man ground crew. The R.VI required a complex 18-wheel undercarriage to support its weight, and carried two mechanics in flight, seated between the engines in open niches cut in the center of each nacelle. The bombs were carried in an internal bomb bay located under the central fuel tanks, with three racks each capable of holding seven bombs. The R.VI was capable of carrying the 1000 kg PuW bomb.
Although designed by Versuchsbau, because of the scope of the project, the production R.VI's were manufactured by other firms: seven by Schütte-Lanz using sheds at Flugzeugwerft GmbH Staaken, Berlin; six by Automobil und Aviatik A.G. (Aviatik) (the original order was for three); and three by Albatros Flugzeugwerke. 13 of the production models were commissioned into service before the armistice and saw action.
The German Naval Air Service had an interest in float-equipped seaplanes so it is no surprize they turned an eye to the prospect of a giant float plane. One Zeppelin-Staaken R.VI was ordered to be converted on September 5, 1917. The new was designatied the Type L and issued the serial number 1432. The Zeppelin-Staaken Type L was powered by four Maybach engines using a 2 tractor, 2 pusher propelller configuration. Unfortunatly the prototype crashed during testing on June 3, 1918.
The project did not die with the 1432. The German Naval Air Service thought results were promising enough to continue development. They showed their confidence in the design with an order of four improved giant float-planes. The Type 8301 was developed from the Zeppelin-Staaken R.VI and the data from the Type L tests. Several important design changes made it an elegant. First change was elevating the fuselage above the lower wing which improved water clearance. To enhance mission flexibility, range became a major factor in mission sucess. The logical choice was to replace munitions with fuel. By eliminating the bomb bays, the range could be extended. enclosing the open gun position on the nose. Production ended after the war, of the four aircraft ordered only three were delivered.
R.VI serial number R.30/16 was the first supercharged aircraft, with a fifth engine - a Mercedes D.II - installed in the central fuselage, driving a Brown-Boveri supercharger. This enabled it to climb to an altitude of 19,100 feet (5,800 m). This same aircraft was later fitted with four examples of one of the first forms of variable-pitch propellers, believed to have been ground-adjustable only.
The R.VI equipped two Luftstreitkräfte (Imperial German Army Air Service) units, Riesenflugzeug-Abteilung (Rfa) 500 and Rfa 501, with the first delivered June 28, 1917.
The units first served on the Eastern Front, based at Alt-Auz and Vilua in Kurland until August 1917. Almost all missions were flown at night with 1,700 pound (770 kg) bomb loads, operating between 6,500 and 7,800 feet (2,000 and 2,400 m) altitude. Missions were of three to five hours' duration.
Rfa 501 was transferred to Ghent, Belgium, for operations against both France and Great Britain, arriving September 22, 1917, at St. Denis-Westrem (Sint-Denijs-Westrem) airdrome. Rfa 501 later moved its base to Scheldewindeke airdrome south of group headquarters at Gontrode, while Rfa 500 was based at Castinne, France, with its primary targets French airfields and ports.
Rfa 501, with an average of five R.VI's available for missions, conducted 11 raids on Great Britain between September 28, 1917, and May 20, 1918, dropping 27,190 kg (29.97 short tons) of bombs in 30 sorties. Aircraft flew individually to their targets on moonlit nights, requesting directional bearings by radio after takeoff, then using the River Thames as a navigational landmark. Missions on the 340-mile (550 km) round trip lasted seven hours. None were lost in combat over Great Britain (compared to 28 Gotha G bombers shot down over England), but two crashed returning to base in the dark.
Four R.VI's were shot down in combat (one-third of the operational inventory), with six others destroyed in crashes, of the 13 commissioned during the war. Six of the 18 eventually built survived the war or were completed after the armistice.