This is the Northrop T-38 Talon. It was the world's first supersonic trainer and to date, is also the most produced. It remains in service as of 2010 in air forces throughout the world. The United States Air Force (USAF) is the largest user. In addition to USAF pilots, the T-38 is used in the United States by NASA astronauts, with the aircraft bailed to NASA from USAF. The Thunderbirds flew the Talon from 1974-1981.