The Sikorsky Ilya Muromets was a class of Russian pre-World War I large four-engine commercial airliners and military heavy bombers used during World War I by the Russian Empire. The aircraft series was named after Ilya Muromets, a hero from Slavic mythology. The series was based on the Russky Vityaz or Le Grand, the world's first four-engined aircraft, designed by Igor Sikorsky. The Ilya Muromets aircraft as it appeared in 1913 was a revolutionary design, intended for commercial service with its spacious fuselage incorporating a passenger saloon and washroom on board. The Ilya Muromets was the world's first multi-engine aircraft in production and at least sixty were built. During World War I, it became the first four-engine bomber to equip a dedicated strategic bombing unit. This heavy bomber was unrivaled in the early stages of the war, as the Central Powers had no aircraft capable enough to rival it until much later.
The Zeppelin-Staaken R.VI was a four-engined German biplane strategic bomber of World War I, and the only Riesenflugzeug design built in any quantity.
The PZL.44 Wicher (gale) was a prototype of 14-seat, twin-engine Polish airliner, built in the Państwowe Zakłady Lotnicze (PZL) in 1938. It was to compete with the DC-2 and Lockheed Super Electra.
The BFW M.20 was a German single-engine, high-wing monoplane ten-seat passenger transport aircraft, developed in the late 1920s and early 1930s. Deutsche Luft Hansa used it throughout the 1930s on a variety of routes.
Rohrbach Ro V was a seaplane manufactured by the Rohrbach Metall-Flugzeugbau company in Berlin, Germany. Only one was built, in 1927. It was delivered to Severa GmbH for comparison flights with the Dornier Do J "Superwal" and as a seaplane trainer. It was used for commercial flights in 1928 by the Deutsche Luft Hansa for the Travemünde to Oslo route.
The Rohrbach Ro VIII Roland was an airliner produced in Germany during the 1920s. It was a conventional strut-braced, high-wing monoplane, based loosely on the Zeppelin-Staaken E-4/20 that Adolf Rohrbach designed in 1920. It had a fully enclosed flight deck and passenger cabin, and featured fixed, tailskid undercarriage. Power was supplied by three engines, one in the nose, and two mounted in nacelles on the wings. Construction was of metal throughout.
The Loire-Nieuport 10 was a 1930s French prototype long-range maritime reconnaissance and combat floatplane produced by Loire-Nieuport, a joint venture between Loire Aviation and Nieuport-Delage. It was an attempt to answer the requirements for the Navy's programme Hydravion éclaireur de combat for a large floatplane capable of acting as a torpedo bomber or reconnaissance aircraft.
The ZSO 523 was a proposed 1940s large military transport designed by the Zeppelin company of Friedrichshafen. During the Second World War Nazi Germany concentrated on building fighters and bombers and the production of support aircraft was transferred to occupied France. The project was abandoned when France was liberated in 1944.
The Rohrbach Ro II was an all-metal, 4-seat reconnaissance and bomber flying boat, designed and produced in Germany in 1923.
The Zeppelin-Staaken R.XVI(Av) was a very large bomber (Riesenflugzeug), designed and built in Germany during 1918.
The Zeppelin-Staaken R.XV was an Imperial German bomber of World War I. An incremental improvement to the Zeppelin-Staaken R.VI, this was one of a series of large strategic bombers called Riesenflugzeuge, intended to be less vulnerable than dirigibles in use at the time.
The Zeppelin-Staaken R.XIV was a development of the Zeppelin-Staaken R.VI. This was one of a series of large bombers called Riesenflugzeuge, intended to be less vulnerable than the dirigibles in use at the time.
The Zeppelin-Staaken R.VII was six-engined large bomber - a Riesenflugzeug - of Imperial Germany, intended to be less vulnerable than the airships in use at the time.
The Zeppelin-Staaken R.V was one of a series of large bombers called Riesenflugzeugen, intended to be less vulnerable than the rigid airships in use at the time.
The Zeppelin-Staaken Riesenflugzeuge were a series of very large bomber aircraft - Riesenflugzeuge, usually powered by four or more engines, designed and built in Germany from 1915 to 1919.
The Rohrbach Ro IV, also known as the Beardmore BeRo.2 Inverness was an all-metal monoplane flying boat of the 1920s. Designed by the German company Rohrbach for the British Royal Air Force, two were ordered, one completed by Rohrbach's Danish subsidiary and the second by the British licensees, William Beardmore and Company, but the type performed poorly during testing and was abandoned.
The Zeppelin-Lindau Rs.IV was a Riesenflugzeug monoplane all metal flying boat with a stressed skin hull and fuselage developed for the Imperial German Navy to perform long range patrols over the North Sea. It had been developed by Claudius Dornier while working for Zeppelin in the town of Lindau.
The Rohrbach Ro III was a twin-engined, all-metal flying boat built in Germany in the mid-1920s. A development of the Ro II, it could be configured either as an airliner or a reconnaissance aircraft. It was developed into the similar but more powerful Ro IIIa Rodra, intended only as a military reconnaissance/bomber. Four Ro IIIs were bought by Japan and two Rodras by Turkey.
The Caproni Ca.131 was a prototype for a large aircraft built in Italy in 1934, intended for use as either a bomber or airliner. It was a conventional low-wing cantilever monoplane, powered by a radial engine on each wing and in the nose. The main undercarriage was housed within large streamlined spats. Configured as an airliner, it would have seated 17 passengers.
The Zeppelin-Lindau Gs.I, often known post-WWI as the Dornier Gs.I after its designer Claude Dornier, was a civil flying boat developed immediate post-war from a military prototype. Its passenger cabin seated six. Only one was completed, and that was eventually scuttled to keep it out of Allied hands. Another of the military prototypes was intended to have a bigger, nine seat cabin and other refinements but the Gs.II was incomplete when discovered by Allied inspectors.
