The Caproni Ca.60 Noviplano was a nine-wing flying boat intended to be a prototype for a 100-passenger trans-atlantic airliner. The prototype only made one short flight on 4 March 1921 over Lake Maggiore in Italy. The aircraft attained an altitude of only 18 m 60 ft, then dived and crashed, breaking up on impact. The pilot escaped unscathed.

Alexander Lippischs Aerodyne, a wingless experimental aircraft. The propulsion was generated by two co-axial shrouded propellers 1968.

De Lackner HZ-1 Aerocycle flying platform, designed to carry one soldier to reconnaissance missions 1954.

Lockheed XFV, The Salmon, an experimental tailsitter prototype escort fighter aircraft 1953.

Snecma Flying Coleoptere C-450, a French experimental, annular wing aeroplane, propulsed by a turbo-reactor, able to take off and land vertically 1958.

Ames-Dryden AD-1 Oblique Wing, a research aircraft designed to investigate the concept of a pivoting wing 1979 1982.

B377PG NASAs Super Guppy Turbine cargo plane, first flew in its outsized form in 1980.

Bartini Beriev VVA-14, a Soviet vertical take-off amphibious aircraft 1970s.

Dornier Do 31, a West German experimental VTOL tactical support transport aircraft 1967.

Hyper III, a full scale lifting body remotely piloted vehicle, built at the NASA Flight Research Center in 1969.

Proteus, a tandem-wing, twin-engine research aircraft, built by Scaled Composites in 1998.

The Airbus A300-600ST Super Transporter or Beluga, is a version of the standard A300-600 wide-body airliner modified to carry aircraft parts and oversized cargo. It was officially called the Super Transporter at first, but the name Beluga became popular and has now been officially adopted.

Vought V-173, the Flying Pancake, an American experimental fighter aircraft for the United States Navy 1942.

Avro Canada VZ-9 Avrocar, a VTOL disk-shaped aircraft developed as part of a secret U.S. military project 1959.

McDonnell XF-85 Goblin, an American prototype jet fighter, intended to be deployed from the bomb bay of the Convair B-36 1948. Photo: U.S. Air Force

Northrop XB-35, an experimental flying wing heavy bomber developed for the United States Army Air Forces during and shortly after World War II. Photo: U.S. Air Force

X-29 forward swept wing jet plane, flown by the NASA Dryden Flight Research Center, as a technology demonstrator 1984 1992.

Stipa-Caproni, an experimental Italian aircraft with a barrel-shaped fuselage 1932.

The Caspian Sea Monster, also known as the Kaspian Monster, was an experimental ekranoplan, developed at the design bureau of Rostislav Alexeyev in 1966.

X-36 Tailless Fighter Agility Research Aircraft, a subscale prototype jet built by McDonnell Douglas for NASA 1996 1997.

Libellula, a tandem-winged and twin-engined British experimental plane which gives the pilot an excellent view for landing on aircraft carriers 1945.