Curtiss-Wright developed X-100 as last major bid to secure share of aircraft market which it had all but lost. Were betting on tilt-rotor concept for vertical landing and take-off (VTOL) operations. X-100 was relatively small plane with deflected exhaust thrust for pitch and yaw control in hovering flight. During 14-hr test program, demonstrated one full conversion to conventional flight, but deflected exhaust thrust proved inadequate for control. X-100 followed by X-19, C-W's last hurrah. X-19 was far more ambitious project intended to be powered by Wankel rotary engines; 2 Lycoming T-55 free turbine jet engines used instead. Drove 4 props, 13 ft in diameter, which were cross shafted fore and aft. Despite marginal power-to-weight ratio, USAF insisted on ejection seats which later saved 2 pilots. X-19 proved to be troublesome combination of promises and problems. Flew total of 3.85 hours. Finally, in Aug 65, gear case failed from fatigue, a propeller was shed, and aircraft pitched up and rolled sharply to left at about 400 ft. Pilots ejected and their new ballistically deployed chutes opened at 230 feet. End of X-19 program. Tilt-rotor concept survived and is basis for XV-22 Osprey. X-100 might have succeeded with today's more powerful and lightweight engines and advanced materials as used in Osprey.