Riesenflugzeug

Siemens-Schuckert R.VIII (1918)

A Riesenflugzeug (plural Riesenflugzeuge, German for "giant aircraft"), sometimes colloquially referred to in English as an R-plane, was a large World War I German bomber, possessing at least three aircraft engines, more usually being powered by four or more engines, sometimes of more than one make, model or power level. These were large multi-engine aircraft capable of flying several hours with larger bomb loads than the smaller Grossflugzeug bombers such as the Gotha G.V. Some of the earliest Riesenflugzeuge were given G-type designations before being redesignated, but a major distinction was that the requirements for the R-type specified that the engines had to be serviceable in flight. As a result, designs fell into two groups - those with the engines mounted centrally inside the fuselage using gearboxes and driveshafts to transfer the power to propellers mounted between the wings, and those with conventional powerplant installations mounted in large nacelles or the nose of the aircraft where engineers would be stationed for each group of engines. The transmission of power from the centrally mounted engines to the remote, most often wing-mounted propellers proved troublesome in practice and most operational examples of Riesenflugzeug-class aircraft were of the second type, as with the all-direct-drive Zeppelin-Staaken R.VI.

The Idflieg (Inspektion der Fliegertruppen (Inspection of the Air Force), the German Army department responsible for military aviation), assigned the letter R to this type of aircraft, which would then be followed by a period and a Roman numeral type number. Seaplanes were denoted by the addition of a lower case "s" after the "R" in the designation.

The Riesenflugzeuge were the largest aircraft of World War I. In comparison, the largest equivalent Allied aircraft were the Sikorsky Ilya Muromets^{[note 1]} with a span of 29.8 m (97 ft 9 in), the Caproni Ca.4 with a span of 29.9 m (98 ft 1 in), the one-off Felixstowe Fury with a span of 37.5m (123 ft) and the Handley Page V/1500 with a span of 38.41 m (126 ft 0 in), of which only three had been delivered by the time the war ended. The Riesenflugzeuge that bombed London during the First World War were larger than any of the German bombers used during the Second World War, and the largest built, the Siemens-Schuckert R.VIII of 1918 had a wingspan of 48.0 m (157 ft 6 in) — it was not until sixteen years later that a larger-wingspanned aircraft, the all-metal Soviet Tupolev Maksim Gorky eight-engined monoplane was built, with an unprecedented 63.0 m (206 ft 8 in) wingspan.

The Riesenflugzeuge, most of which were built as "one-off" aircraft, were operational from 1915 to 1919.

List of aircraft

Type	Engines	Span	First flight	Service	Notes	Number built
AEG R.I	4 × 260 hp Mercedes D.IV	36 m (118 ft 1 in)	1916	None	broke up in flight in 1918	1 completed, 7 more partially built
DFW R.I	4 × 220 hp Mercedes D.IV	29.5 m (96 ft 9 in)	1916	Eastern Front	crashed on 2nd combat flight[1]	1
DFW R.II	4 × 260 hp Mercedes D.IVa	30.06 m (98 ft 7 in)	1918	Trainer as unsuitable for combat		2 of 6 ordered
DFW R.III	8 × 260 hp Mercedes D.IV	53.5 m (175 ft 6 in)	n/a	None	Incomplete at end of war, cancelled	None
Linke-Hofmann R.I	4 × 260 hp Mercedes D.IVa	33.2 m (108 ft 11 in)	1917	None	First example had 32.02 m (105 ft 1 in) span[1]	4
Linke-Hofmann R.II	4 × 260 hp Mercedes D.IVa	42.16 m (138 ft 4 in)	1919	None	Used largest single propeller ever built, some 6.9 meters in diameter	2
Poll/Forssman Giant[2]	10 × unk. engines	50.3 m (165 ft 0 in)	n/a	None	Cancelled incomplete	None
Siemens-Schuckert Forssman R	2 × 110 hp Mercedes D.III & 2 × 220 hp Mercedes D.IVa	24.0 m (78 ft 9 in)	1915	Trainer		1
Siemens-Schuckert R.I	3 × 150 hp Benz Bz.III	28.0 m (91 ft 10 in)	1915	Eastern Front & training	[1]	1
Siemens-Schuckert R.II	3 × 260 hp Mercedes D.IVa	38.0 m (124 ft 8 in)	1915	Training	span increased[1]	1
Siemens-Schuckert R.III	3 × 220 hp Benz Bz.IV	34.33 m (112 ft 8 in)	1915	Training	[1]	1
Siemens-Schuckert R.IV	3 × 220 hp Benz Bz.IV	37.6 m (123 ft 4 in)	1916	Training	Span increased[1]	1
Siemens-Schuckert R.V	3 × 220 hp Benz Bz.IV	34.33 m (112 ft 8 in)	1916	Eastern front	Span increased[1]	1
Siemens-Schuckert R.VI	3 × 220 hp Benz Bz.IV	33.36 m (109 ft 5 in)	1916	Eastern front	Span increased[1]	1
Siemens-Schuckert R.VII	3 × 260 hp Mercedes D.IVa	38.44 m (126 ft 1 in)	1917	Eastern front	[1]	1
Siemens-Schuckert R.VIII	6 × 300 hp Basse und Selve BuS.IVa	48.0 m (157 ft 6 in)	n/a	None		2 (one unfinished)
Zeppelin-Lindau Rs.I	3 × 240 hp Maybach Mb.IV	43.5 m (142 ft 9 in)	n/a	None	Wrecked unflown, 1915[note 2]	1
Zeppelin-Lindau Rs.II	3 × 240 hp Maybach Mb.IV	33.2 m (108 ft 11 in)	1916	None	[note 2]	1
Zeppelin-Lindau Rs.III	3 × 245 hp Maybach Mb.IVa	37.0 m (121 ft 5 in)	1917	Evaluation	[note 2]	1
Zeppelin-Lindau Rs.IV	4 × 245 hp Maybach Mb.IVa	37 m (121 ft 5 in)	1918	None	[note 2]
Zeppelin-Staaken VGO.I	3 × 240 hp Maybach HS or 5 × 245 hp Maybach Mb.IVa	42.2 m (138 ft 5 in)[note 3]	1915	Kaiserliche Marine	[note 4]
Zeppelin-Staaken VGO.II	3 × 240 hp Maybach HS	42.2 m (138 ft 5 in)[note 3]	1916	Eastern front & trainer	[note 4][1]
Zeppelin-Staaken VGO.III	6 × 160 hp Mercedes D.III	42.2 m (138 ft 5 in)[note 3]	1916	Eastern front	[note 4][1]
Zeppelin-Staaken R.IV	2 × 160 hp Mercedes D.III & 4 × 220 hp Benz Bz.IV	42.2 m (138 ft 5 in)[note 3]	1917?	Eastern front & Western front	One built
Zeppelin-Staaken R.V	5 × 245 hp Maybach Mb.IVa	42.2 m (138 ft 5 in)[note 3]	1917?	Western front	One built
Zeppelin-Staaken R.VI	4 × 260 hp Mercedes D.IVa	42.2 m (138 ft 5 in)[note 3]	1917?	Western front	18 built
Zeppelin-Staaken R.VII	2 × 160 hp Mercedes D.III & 4 × 220 hp Benz Bz.IV	42.2 m (138 ft 5 in)[note 3]	1917	None	Wrecked on delivery
Zeppelin-Staaken R.XIV	5 × 245 hp Maybach Mb.IVa	42.2 m (138 ft 5 in)[note 3]	1918	Western front	Three built
Zeppelin-Staaken R.XIVa	5 × 245 hp Maybach Mb.IVa	42.2 m (138 ft 5.5in)[note 3]	?	Post-war	Seized while smuggling
Zeppelin-Staaken R.XV	5 × 245 hp Maybach Mb.IVa	42.2 m (138 ft 5.5in)[note 3]	1918	Western Front
Zeppelin-Staaken R.XVI	2 × 530 hp Benz Bz.VI & 2 × 220 hp Benz Bz.IV	42.2 m (138 ft 5 in)[note 3]	1918	Airliner	Two completed, 3rd unfinished[note 5]
Zeppelin-Staaken L	4 × 245 hp Maybach Mb.IVa	42.2 m (138 ft 5 in)[note 3]	?	None	Floatplane variant. Wrecked in trials.[note 6]	1
Zeppelin-Staaken Type 8301	4 × 245 hp Maybach Mb.IVa	42.2 m (138 ft 5 in)[note 3]	?	floatplane airliner	3 built for Kaiserliche Marine	3

References

Notes

1. The first successful large aircraft, and the inspiration for the German Grossflugzeug and Riesenflugzeuge bombers
2. Flying-boat developed by Claudius Dornier while working for Zeppelin.
3. The essentially same wing structure was used for nearly all 42.2 meter wingspan Zeppelin R-series aircraft.
4. Built at Versuchsbau Gotha Ost to Zeppelin design
5. One built during war which did not see any service. One was never completed. One was built as a civilian airliner
6. Built for Kaiserliche Marine

Citations

1. Haddow, 1962, p.67
2. G. Sollinger, "The Forssman Tri-plane, The Largest Aeroplane Of World War I" The Forssmann-Triplane

Bibliography

• Gray, Peter; Thetford, Owen (1962). German Aircraft of the First World War. London: Putman.
• Haddow, G.W.; Grosz, Peter M. (1962). The German Giants, The Story of the R-planes 1914–1919. London: Putman.
• Sollinger, G. (2009). Villehad Forssman: Constructing German Bombers 1914-1918. Moscow: Rusavia Publishing House.

External links

• "The (German) Dornier "Giant Flying-Boat"" (PDF). Flight. XI (38): 1258. September 18, 1919. No. 560. Retrieved January 12, 2011. Brief contemporary technical description of the Dornier Rs.III or Rs.IV, with rough diagrams.
• "The Four-engine Giant" Notes on German Bombers in 1918 issue of Flight
• "The Linke-Hofmann Giant Machines", p.2, p.3 & p.4 in 1919 issue of Flight
• "The German D.F.W. Commercial Four-Engined Biplane", p.2, p.3, p.4 & p.5 in 1919 issue of Flight