The Northrop T-38 Talon is an American supersonic jet trainer. 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 by United States NASA astronauts, the U.S. Naval Test Pilot School (other T-38s were previously used as USN aggressor aircraft), as well as some NATO pilots participating in a joint training program. A few are also under civilian ownership.

The basic airframe was used for the light combat aircraft F-5 Freedom Fighter family. In the 1950s Northrop began studying lightweight and more affordable fighter designs. The company began with its single-engine N-102 “Fang” concept. The N-102 was facing weight and cost growth, so the project was canceled and the company N-156 project was begun.

Although the United States Air Force had no need for a small fighter at the time, it became interested in the trainer as a replacement for the T-33 Shooting Star it was then using in this role. The first of three prototypes (designated YT-38) flew on 10 March 1959. The type was quickly adopted and the first production examples were delivered in 1961, officially entering service on 17 March that year, complementing the T-37 primary jet trainer. When production ended in 1972, 1,187 T-38s had been built. Since its introduction, it is estimated that some 50,000 military pilots have trained on this aircraft. The USAF remains one of the few armed flying forces using dedicated supersonic final trainers, as most, such as the US Navy, use high subsonic trainers.

The fuel crisis of the early 1970s resulted selection of the Northrop T-38A Talon, a supersonic trainer by the USAF Thunderbirds. Five T-38s used the same amount of fuel needed for one F-4 Phantom, and fewer people and equipment were required to maintain the aircraft. Although it met the criteria of demonstrating the capabilities of a prominent Air Force aircraft, the Talon did not fulfill the Thunderbird tradition of flying front-line jet fighters. The team flew the Talon from 1974–1981.