The SEPR 841 rocket engine was also retained. The Mirage IIIA was also fitted with a Thomson-CSF-built Cyrano Ibis air intercept radar, operational-standard avionics, and a drag chute to shorten its landing roll. During May 1958, the first Mirage IIIA conducted its first flight. During October of that year, this aircraft achieved a top speed of Mach 2.2 during one of its test flights, thus becoming the first European aircraft to exceed Mach 2 in level flight. During December 1959, the tenth and final Mirage IIIA was rolled out; the last six pre-production aircraft were largely representative of the subsequent initial production standard. The test regime involved a wide variety of tasks, including the evaluation of the newer SEPR 841 rocket motor, various underwing drop tanks, and other major systems. One Mirage IIIA was powered by a Rolls-Royce Avon 67 engine capable of generating of thrust, to serve as a test model for Australian evaluation, which was given the "Mirage IIIO" designation. This variant flew in February 1961, but the Avon powerplant was ultimately not adopted upon production aircraft. The first major production model, the "Mirage IIIC", first flew in October 1960. The IIIC was largely similar to the earlier IIIA, being less than a half meter longer and featuring a full operational fit. The Mirage IIIC was a single-seat interceptor, with an Atar 09B turbojet engine, featuring an eyelid type variable exhaust. The Mirage IIIC was armed with twin 30 mm DEFA cannon fitted in the belly with the gun ports under the air intakes. Early Mirage IIIC production had three stores pylons, one under the fuselage and one under each wing; another outboard pylon was soon added to each wing, for a total of five, excluding a sleek supersonic tank which also had bomb-carrying capacity. The outboard pylon was intended to carry an AIM-9B Sidewinder air-to-air missile, later replaced by the Matra R550 Magic and also was armed with the radar guided Matra R530 Missile on the center line pylon. A total of 95 Mirage IIICs were obtained by the French Air Force ("Armée de l'Air", AdA), with initial operational deliveries in July 1961. The Mirage IIIC remained in service with the AdA until 1988. The "Armée de l'Air" also placed an order for a two-seat "Mirage IIIB" operational trainer.