On October 2, 1959, the Mirage III B made its first flight at Melun-Villaroche, with René Bigand at the controls.
Designed and built within the framework of the light interceptor program defined by the French Air Force after the Korea war (1950-1953), the Mirage III was a bomber fighter aircraft with a delta wing and a fuselage designed according to the area rule which gave it a distinctive waisted profile. Derived from the first Mirage formula with a Delta wing, the Mirage III is designed at the end 1955.
Ordered on February 25, 1958, the Mirage III B was the dual-control two-seater version of the Mirage III A. The prototype first flew at Melun-Villaroche on October 20, 1959, piloted by René Bigand. Compared to the basic Mirage III, its fuselage was elongated to house the second crew member in what had been the radio equipment bay. The equipment was relocated in the nose cone, which therefore no longer contained radar.