The 1950s were the Golden Age of X-Planes.  With the Cold War in full swing, the United States and the Soviet Union poured hundreds of millions of dollars (and rubles) into the conception, development and testing of all manner of imaginative experimental and combat aircraft.   From planes with wings that changed position in flight to combination airplane/helicopters to VTOL "tail sitters" to flying jeeps, both superpowers were prepared to build just about anything that might give them even the slighted strategic or tactical advantage in the air.

Like most experiments in any field, the vast majority of 1950s-era X-Planes and prototypes failed to perform up to their creators' expectations.  But enough was learned from even the magnificent failures to push aircraft development forward at a pace so swift that most planes were obsolete within days of making their maiden flights.

BELL X-5 (1951)

DOUGLAS X-3 STILETTO (1952)

SUD-OUEST SO-9000 TRIDENT (1953)

McDONNELL  XV-1 CONVERTIPLANE (1954)

LOCKHEED XFV-1 "SALMON" (1954)

 CONVAIR XFY-1 "POGO" (1954)

BELL X-14  (1954)

FAIREY DELTA 2 (1954)

BELL XV-3 TILT-ROTOR CONVERTIPLANE (1955)

NORD 1500 GRIFFON II (1955)

DOUGLAS D-558-3 "SKYFLASH: (1955)

AVRO 730 (1956)

REPUBLIC XF-103 THUNDERWARRIOR (1957)

CURTISS WRIGHT VZ-7AP (1958)

PIASECKI ZV8-P AIRGEEP  (1958)

DOAK VZ-4DA V/STOL (1958)

AVROCAR VZ-9 (1959)

SNECMA C.450 COLÉOPTÈRE (1959)

HILLER X-18 TILT-WING VTOL (1959)

X-Planes & Prototypes

1900-1930

1940s

1950s

1960s

1970s

1980s

1990s

2000 and Beyond