Origins and prototypes
In mid-1964, aware of the dead end represented by aircraft with large engines too expensive for export, Marcel Dassault had initiated a discrete design for a small Mach 2 aircraft on Corporation funds. The Mirage III E 2, a single-seater with a sweptback wing like the Mirage III F2 and equipped with a Snecma Atar 9 K jet engine exactly like the Mirage IV A, was primarily intended for export. As of the end of 1965, he launched the manufacture of a prototype suitable for the Air Force with contribution of industrial partners. It would be named the Mirage F1.
The French Air Force staff’s need for an aircraft to supplant its earliest Mirage IIIs, and simultaneously one able to land at slower speeds, triggered the Mirage F1 program.
The Air Force staff drafted its specifications for an all-weather low-altitude intruder in 1963. That plane, they stipulated, required supersonic interception capabilities, needed to use short and rudimentarily-equipped landing strips, and approach at less than 140 knots (260 km/h).
It also needed to accommodate two basic operational factors: longer autonomy and mission radii, and shorter take-off and landing distances freeing it from having to use easy-to-spot and exposed larger runways – at the lowest possible cost. The Mirage III family’s delta wing meant pilots needed to approach and land at high speed. Extensive research on minimum combat aircraft speeds led Dassault to look at swept-wing designs which, at that point in development, were the ones able to house high-lift flaps.
When France announced its intention to withdraw from NATO’s integrated military organization in 1966, the Air Force began focusing on an interceptor with secondary penetration capabilities. Dassault’s engineering department started working on the Mirage F3, but finally shelved the plans because the withdrawal from NATO’s integrated military organization entailed reshuffling the entire combat equipment policy. The successive cancellations left Dassault without a successor for its Mirage III. The need to overcome that deadlock, and to secure a future if the variable-sweep aircraft program was also aborted, led Marcel Dassault to start working on a new prototype, the Mirage F1, a smaller version than the Mirage F2 and Mirage F3.
The experience designing the Mirage F2 proved valuable in efforts to develop the Mirage F1, a lighter (7.4 ton unladen) single-seater. Its light weight made it especially suitable for interception. One of the Mirage F1’s features is its ample airspeed variations. It can fly at Mach 2 and land at 125 knots, thanks to its wing’s extraordinary lift augmentation from its leading edge nose and double-slot flaps which are gruelingly difficult to fit on thin wings.
Equipped with an interim Snecma Atar 9 K 31 jet engine, the Mirage F1 01 made its first flight on December 23, 1966 at Melun-Villaroche piloted by René Bigand. On January 7, 1967, he reached Mach 2 on the 4th flight.
Flight trials continued until, during a low-altitude high-velocity pass, the horizontal stabilizers of Mirage F1 01 broke away due to a divergent vibration phenomenon called ‘flutter’ and the aircraft struck the ground near Fos-sur-Mer, killing Dassault chief pilot René Bigand. Despite the accident, notification was given of an order for three pre-production aircraft: the Mirage F1 02, 03 and 04 with the Atar 9 K 50 jet engine.
Mirage F1 02 (Atar P l 31) accomplished its first flight at Istres on March 20, 1969 piloted by Jean-Marie Saget and reached Mach 1.15. Mirage F1 03 equipped with a Snecma 9 K 50 engine flew on September 18, 1969, and Mirage F1 04 equipped with all the on-board electronics designed for the production aircraft, on June 17, 1970.
Production and operational experience
The first flight of the first production model took place at Mérignac on February 15, 1973, piloted by Guy Mitaux-Maurouard. On March 14, 1974, it was delivered to the Air Force. The production models differed from the prototypes by the installation of slotted leading edge (inspired by the Jaguar) on the outboard two thirds of the wing, which increased the maximum angle of attack. As with the other serially-produced aircraft, a number of partner firms and subcontractors were involved in production.
The Mirage F1 led to the creations of several versions.
The Mirage F1 C
The Mirage F1 C was the basic version optimized for all-weather all-altitude air defense. Later, two new versions (the Mirage F1 CR and the Mirage F1 CT) were used to equip the Air Force when the Mirage III R and III E reached the end of their term.
The Mirage F1 A
It was the day version of the F1 C with simplified electronic equipment and additional fuel capacity. This version was realized at the request of South Africa as the F1 AZ.
The Mirage F1 B
It was the two-seat version of the Mirage F1 C. This version, initially developed at the request of Kuwait was also acquired by the French Air Force.
The Mirage F1 R
Optimized for low-altitude day and night reconnaissance, the Mirage F1 R was the export version of the F1 CR used by the French Air Force.
From the outset, the Mirage F1 was an export success : 473 aircraft equipped the Air Forces of South Africa, Spain, Greece, Kuwait, Libya, Morocco, Ecuador, Iraq, Jordan and Qatar.
The Dassault Corporation designed the export Mirage F1 E which could fulfill all the missions of the F1 C but was equipped with avionics for more precise air-to-ground missions and longer firing distances.
|Unladen weight||7 400 kg|
|Max. Speed Top mach level flight||> 2|
|Max. height Practical ceiling||18 500 m / 60 700 ft|
|Type||Snecma Atar 9 K 50 70.6 kN|