In 1954, Bell built their Model 65 Air Test Vehicle (ATV) of parts from a number of commercial aircraft. A 1,000 lb thrust Fairchild J-44 missile turbojet engine mounted on each side of the aircraft under the wing could be tilted from vertical to horizontal. A Turbomeca Palouste turbocompressor provided reaction jets at the tail and wingtips for control in hover.

It made its first hover on 16 November 1954 from a platform to prevent the ATV from reingesting its exhaust gases.

The ATV was modified with a wheeled landing gear and made horizontal flights in 1955. It made partial conversions at altitude, but had inadequate engine thrust to complete the transition. Bell ended the program in 1955 in favor of its X-14 (#18), but used this tilt jet experience to develop the Air Force XF-109 V/STOL fighter concept; although canceled before being built, this concept was very similar to the later VJ 101C.

Source: AHS V/STOL Wheel