In 1951, the Corporation secured a contract for the production and provision of an MD 452 Mystère IV derived from the Mystère II, capable of reaching Mach 1 in a dive.
On August 2, 1951, the Corporation secured a contract for the production and provision of an MD 452 Mystère IV derived from the Mystère II capable of reaching Mach 1 in a dive, although production was not envisaged. A new wing was designed. Compared to the Mystère II, it had a biconvex profile with a greater sweepback (38° as against 30°) and lower relative thickness ratio (7,5 % as against 9 %). The narrower fuselage was circular in section in the fore and aft, with a wide-base pear-shaped central body.
The Mystère IV 01 was equipped with a centrifugal Rolls Royce Tay engine, this being more powerful and more reliable than the axial Atar engine which the Air Force preferred but had still not completed its development. The maiden flight of the Mystère IV 01, piloted by Kostia Rozanoff, took place at Melun-Villaroche, on Septembre 28, 1952. It lasted 25 minutes. Using the same jet engine as the Mystère II, it reached Mach 0.92 (against 0.87) flying horizontally. On its 34th flight, on 17 January, 1953, it broke the sound barrier nose down.
The qualities of the new aircraft prompted the authorities, in October 1952, to place an order for 22 pre-production. It was canceled, substituting an order for 8 Mystère IV A (n° 02 à 09), with the Rolls-Royce Tay engine as a consequence of the choice in December 1952 of the US Air Force delegation led by General Richard Boyd and Charles « Chuck » Yeager to test out French combat aircraft.
On April 25, the Secretariat of State for Aviation ordered 225 aircraft plus support equipment, to be delivered starting from June 1954. They were a gift to the French Air Force.
The first production-standard Mystère IV A flew at Mérignac, on May 29, 1954, with Paul Boudier at the controls. It was officially handed over to the American authorities on June 18. The 225th aircraft was delivered in June 18, 1956, twelve days ahead of a contract date.
The first Mystère IV A to be delivered to the Air Force was accepted by the 12th Cambrai Wing on May 25, 1955. It was at the Cambrai base that the first aerobatics team was trained on the new aircraft. On July 14, 1955, twelve of them flew in formation over the Champs Elysées for the Bastille Day parade.
In all, 411 aircraft were manufactured and delivered, whether to the French Air Force or for export, from 1954 to 1958; 114 were equipped with the Rolls-Royce Tay, all the others (particularly the export models) with the Hispano-Suiza Verdon 350 (a more powerful version of the Tay). The last of the 242 French Mystère IV A was delivered to the Air Force on November, 27, 1958. It finished its working life at the 8th Cazaux Fighter Wing, where it was used for fighter pilot training.