The T-33 jet trainer was derived from the Lockheed F-80C Shooting Star, the USAF's first operational jet fighter, in 1948. In the fifty years since its introduction the T-33 has trained more jet pilots than any other training type. In addition to this role, it has served, and continues to serve, as an attack fighter – the AT-33 – and as a reconnaissance aircraft – the RT-33 – in several foreign air forces. It was also a testbed in many development programs including tests on ejection seats and missile guidance systems, and continues yet today in various military and civilian roles.