The Mirage III T made its first flight at Istres on January 25, 1965, piloted by Jean Coureau.
On August 29, 1961, the DTIA ordered the design and development of two Mirage III V vertical take-off prototypes to be produced conjointly by Dassault Aviation and Sud-Aviation.
The Mirage III V, a Mach 2 aircraft heavier than the Balzac, prefigured the operational version. It had eight Rolls-Royce RB 162-1 lift jets and a Snecma TF 106 with afterburner, the French version of the Pratt&Whitney JTF 10 turbofan.
To test out the American engine, a Mirage III was transformed into a flying test-bed, the Mirage III T. The airframe was initially equipped with a TF 104 (49kN of thrust with after-burning), but made its first flight – at Istres on January 25, 1965, piloted by Jean Coureau – with a more powerful TF 106 (73.5 kN of thrust with after burning). The development of these engines was problematic ; they frequently stalled on take-off, leaving Jean Coureau to make his own way back… on foot.