The two prototype aircraft were used to expand the flight envelope of the aircraft as quickly as possible and prove that the design calculations for supersonic flight were correct.
F-WTSS (production designation 001) was the first Concorde to fly, on 2 March 1969, and was retired on arrival at the French air museum at Le Bourget Airport on 19 October 1973, having made 397 flights covering 812 hours, of which 255 hours were at supersonic speeds.