Ex-USAF 62-5924. Long before the V-22 Osprey came along, extensive tests were conducted with five examples of this tilt-wing design, with a first conventional flight in 9.64 and vertical take-off with transition to normal flight and back for vertical landing in 1.65. Excessive vibration and noise from the cross-linked drive shaft and wing flexing were major problems, but the concept showed promise. A joint USAF/Army/Navy project, the USN withdrew and interest faded, the last LTV XC-142A flying into the USAFM in 1970