The Rockwell-Messerschmitt-Bölkow-Blohm X-31 was an experimental jet fighter designed to test fighter thrust vectoring technology.
It was designed and built by Rockwell and Messerschmitt-Bölkow-Blohm (MBB), as part of a joint US and German Enhanced Fighter Maneuverability program to provide additional control authority in pitch and yaw, for significantly more maneuverability than most conventional fighters. An advanced flight control system provided controlled flight at high angles of attack where conventional aircraft would stall or lose control. Two aircraft were built, of which only one has survived.
The X-31 design was essentially an all-new airframe design, although it borrowed heavily on design elements and sometimes actual parts of previous production, prototype, and conceptual aircraft designs, including the British Aerospace Experimental Airplane Programme (choice of wing type with canards, plus underfuselage intake), the German TKF-90 (wing planform concepts and underfuselage intake), F/A-18 Hornet (forebody, including cockpit, ejection seat, and canopy; electrical generators), F-16 Fighting Falcon (landing gear, fuel pump, rudder pedals, nosewheel tires, and emergency power unit), F-16XL (leading-edge flap drives)
The C-124 first flew on 27 November 1949, with the C-124A being delivered from May 1950. The C-124C was next, featuring more powerful engines, and an APS-42 weather radar fitted in a “thimble”-like structure on the nose. Wingtip-mounted combustion heaters were added to heat the cabin, and enable wing and tail surface deicing. The C-124As were later equipped with these improvements.
An air force, also known in some countries as an aerospace force or air army, is in the broadest sense, the national military branch that primarily conducts aerial warfare.