The Rockwell XFV-12A was a prototype United States Navy fighter built in 1977. On paper, designers thought it would easily be a Mach 2 fighter and utilizing the AIM 7 Sparrow it would be a world beater. One more advantage this plane had was a VTOL capabilities. Powered by the Pratt & Whitney F401-PW-400, the 30,000 lbs of vectored thrust never did much except in tethered tests. It suddenly and mysteriously was defunded. This plane never left the ground and was abandoned.