Twin-fuselage aircraft

A twin-fuselage aircraft has two main fuselages. It is distinct from the twin-boom aircraft configuration which has a main body with two subsidiary boom structures.

Twin fuselages have been adopted for various reasons, and a few types have entered production.

Early seaplanes

During and after World War I a number of twin-fuselage floatplanes and twin-hulled flying boats were constructed, and several entered production:

The Blackburn T.B. of 1915 was a long-range floatplane for anti-Zeppelin patrol. A handful of production examples were delivered but few were used operationally.

The British Wight Twin Seaplane of 1916 was a prototype long-range floatplane intended to carry an 18 inch torpedo. Its design was a twin-fuselage variant of the earlier Wight Twin Landplane of twin-boom configuration, i.e. with the central nacelle removed and the crew housed in the remaining bodies on either side. The French Labourdette-Halbronn H.T. 1 and H.T.2 flying boat prototypes of 1918-1919 were intended for a similar role.

Savoia-Marchetti produced two twin-hulled flying boat types, the S.55 multirole flying boat of 1924 and the S.66 airliner of 1931, both of which took advantage of a twin hull/fuselage to provide the same stability of a twin float design, but with a hull. The S.55 proved very successful, being produced in large numbers.

The Tupolev ANT-22 flying boat prototype conceptually followed the Savoia's, but was much larger and despite flying in 1934 never progressed beyond a single prototype due to poor performance.

Heavy glider tug

During World War II the need arose for a heavy glider tug capable of towing the large Gotha Go 242 and even larger Messerschmitt Me 321 Gigant. The Heinkel He 111Z Zwilling (twin) was created by joining two He 111 fuselages with a new wing centre section and adding a fifth central engine. Although liked by its pilots when it first flew in 1941, even the 111Z could not tow a fully laden Gigant, and although a small batch became operational they saw little action.

A few variants were developed for roles such as long-range reconnaissance or air-launched anti-ship missile carrier, but none entered service.

Heavy fighters

During World War II a need sometimes also arose for a heavy fighter, which could not be met by a new design in the time needed. Joining two examples of an existing lighter aircraft was one way to achieve this.

The German Messerschmitt Bf 109Z twin (Zwilling) Bf 109 prototype was destroyed in an attack by the British in 1943 before it was completed, and the project subsequently abandoned. The later Me 609 twin Me 309 project was never built.

In 1944 Dornier proposed the Dornier Do 635 long-range reconnaissance variant of the Do 335 Pfeil heavy fighter, to have twin Do 335 fuselages and four engines. It was never built.

The Italian Savoia-Marchetti SM.92 prototype was unusual in being an adaptation of a twin-boom design but did not enter production.

The North American F-82 Twin Mustang arrived too late to enter service during the War but later saw service in the Korean war.

Space launchers

More recently the idea of a dedicated re-usable mothership design capable of carrying and launching a spacecraft has gained interest. The twin fuselage configuration offers the advantage of a clean payload area underneath the wing centre section.

The Scaled Composites White Knight Two is under development, with the first example now flying.

Past projects have included the Conroy Virtus and Twin fuselage Lockheed C-5 Galaxy Shuttle transport aircraft of 1974.

Current projects include the Scaled Composites Model 351 Roc proposed for Stratolaunch and NASA's Towed Glider Air-Launch Concept.

List of twin-fuselage aircraft

Types are listed in chronological order of first flight or, for those which never flew, of project announcement.

Type Country Date Role Status Description
Belyayev DB-LK 1940 Bomber Prototype
Bestetti BN.1 1940 Light Experimental Sportplane.
Blackburn T.B. United Kingdom 1915 Production Patrol floatplane.
Blériot 125 France 1931 Airliner Prototype 12 seats.
Caproni Ca.4 Italy 1915 Bomber and transport Production Series of types.[1]
Conroy Virtus 1974 Transport Project Shuttle transport
Dornier Do 635 1944 Fighter Project Twin Dornier Do 335 Pfeil proposal.
Twin Ercoupe 1946 Twin ERCO Ercoupe one-off conversion.
Fokker K.I 1915 Prototype Kampfflugzeug (triple fuselage )
Fouga CM.88 Gemeaux France 1951 Experimental Twin Cyclope, jet engine testbed, 2 built[2]
Heinkel He 111Z 1941 Glider tug Production Variant of the He 111.
Labourdette-Halbronn H.T.1 and H.T.2 1918 and 1919 Torpedo bomber Prototype Flying boat. One H.T.1 (1918) and two H.T.2 (1919) flown. [3]
Twin fuselage Lockheed C-5 Galaxy 1974 Transport Project Shuttle transport aircraft proposal.[4][5]
Messerschmitt Bf 109Z Germany 1943 Fighter Unfinished Twin Bf 109 prototype. Destroyed while under construction.[6]
Messerschmitt Me 609 Germany 1941 Fighter Project Twin Me 309 proposal.[6]
North American F-82 Twin Mustang USA 1945 Long-range fighter Production
Pipistrel Taurus G4 2011 Experimental Prototype Electric aircraft and competition winner.
Savoia-Marchetti S.55 Italy 1924 Multirole Production Flying boat.
Savoia-Marchetti S.66 Italy 1931 Airliner Production Flying boat.
Savoia-Marchetti SM.92 Italy 1943 Heavy fighter Prototype
Scaled Composites Model 348 White Knight Two USA 2008 Spacecraft launcher Prototype
Scaled Composites Model 351 Roc USA 2011 Spacecraft launcher Project Launcher for Stratolaunch spacecraft.
Scaled Composites Model 367 BiPod USA 2011 Experimental Flying car, carried out "hops" under wheeled power.
Thomas-Morse MB-4 USA 1920 Mail plane Prototype
Towed Glider Air-Launch Concept USA 2013 Spacecraft launcher Project NASA Dryden[7]
Tupolev ANT-22 1934 Prototype Twin-hulled flying boat.
Wagner Twin Cub 1952 Prototype Twin Piper Cub one-off conversion.[8]
Wight Twin Seaplane 1916 Prototype Variant of the Wight Twin Landplane of twin boom configuration.

References

Notes

  1. ↑ "The Caproni Bombing Triplane CA-4-1915", Flight, Volume XI, Issue 25, No. 547, 19 June 1919, pp. 797–799. Retrieved: 29 October 2013.
  2. ↑ http://johnlinde.ca/Early_Designs.html
  3. ↑ Davilla, J.; French aircraft of the first World War (2002), Flying Machines Press, Page 287
  4. ↑ Tails through time
  5. ↑ Shuttling the Shuttle: Twin fuselage C-5 Galaxy
  6. ↑ 6.0 6.1 Green, W.; Warplanes of the Third Reich, Macdonald and Jane's, 1970.
  7. ↑ 'Gliding' to Space: A Novel Means of Launching Space Satellites
  8. ↑ http://www.twinnavion.com/oddballs.htm

Bibliography

See also