The Fiat G.91 is a jet fighter aircraft designed and built by the Italian aircraft manufacturer Fiat Aviazione, which later merged into Aeritalia.
The G.91 has its origins in the NATO-organized NBMR-1 competition started in 1953, which sought a light fighter-bomber (officially, the competition was seeking a "Light Weight Strike Fighter") to be adopted as standard equipment across the air forces of the various NATO nations. The G.91 was specifically designed to fulfil the requirements of this competition, being relatively lightweight and capable of operating from austere airstrips while also being armored and suitably armed while remaining relatively affordable in comparison to many frontline fighters. On 9 August 1956, the prototype conducted its maiden flight. After reviewing multiple submissions, the G.91 was picked as the winning design of the NBMR-1 competition.