Some precursors :
The 1953 fighter program :
The competitors :
The Mystère Delta :
From Mirage I to Mirage III :
Pre production Mirages :
 

Some precursors :

    The delta wing has been invented by scientists who were trying to improve their planes' flight caracteristics when approaching mach 1. According to a theory of von Buseman, they began to reduce the wing's thickness, then they increased its chord, in order to reduce its drag and delay the apparition of schockwaves at transsonic speeds. This led finally to an insufficient stiffness which in some cases, would break the plane.
    Then, plane designers reminded Alexander Lippisch. This engineer had been studying a delta fighter, which had even taken the air as an experimental glider, the Lippisch DM 1,  in 1943.The delta wing formula has a lot of advantages : important chord, very high stifness, a lot of space inside for fuel storage, and no need for tailplanes, which allows a much simpler control system.
    Obviously there was a price to pay for all this : high speed and high alpha landings. Nevertheless, the idea had to be a worldwide successs. The first real delta airplane will be the Convair XF 92, forerunner of the successful F 102 and F 106.

The 1953 light fighter program :

    Draught in januaryand dispatched to the aircraft companies on february 4th of 1953 this requirement for proposal aims to procure to the "armée de l'air" a specilaized interceptor enabling her to crush the waves of soviet bombers expected to surge down western Europe at any momment. The requirement was for : " a less than four tons interceptor able to climb to 15000 m in 4 minutes, able of a level flight at mach 1.3 in order to catch an hostile flying at mach 1 more than 25 Km away, able to carry a Missile weighting 200 kg, to come back to his airbase, wait five minutes and land at a speed of less than 180 km/h.
 

The competitors :

    At "Sud ouest aviation" (Bordeaux), the SO 9000 "Trident" flies for the first time on march 2nd 1953. This aircraft is an interceptorpwered by a mix of three 1500 kgp rocket motrors and two Turboméca "Marboré II" turboreactor.

    At the SNCASE (Société nationale de Construction Aéronautique du Sud Est, Toulouse) Pierre Satre, head of the design bureau, and his team work hard on the SE 212 "Durandal". This aircraft's maiden flight won't happen before april 20th 1956 due to the high workload related to the Caravelle airliner.

    The Dassault proposition is a quite innovating design : the MD 550 "Mystère Delta", a bireactor ( 2 turboréacteurs MD 30 de 750 Kgp) which maiden flight will occure on july 25th 1955.

The "Mystère Delta" :

    The test pilot, Roland Glavany regrets the lack of yaw control,but he has a good opinion of the aircraft, which in spite of an obvious lack of power will reach mach 1.15 thanks to a light dive.At the end of january, the mystère Delta undergoes a batch of minor modifications : wingspan reduced by 30 cm, backstepped fin with tilted trailing edge instead of the former vertical trailing edge and new  MD 30R powerplants, "R" standing for "reheat".Those engines, actually Dassault Built Rolls Royce "Viper",give an exceptional 950 Kgppower thanks to a reheat designed by engineer Jean Ritzenhaler. The last improvement is the fitting of the SEPR rocket engine pack.

From Mirage I to Mirage III :

   The aircraft which resumes trials on june 25th of 1956 is not really a new plane. However, the Dassault executives have found a new name for it : the "Mirage". The MD 550 becomes the Mirage I.
    This particular aircraft has however no future and will be used to demonstrate the advantages of the delta wing formula.The french air ministry has decided to change the 1953 specification and issues in july 1956 a new program requiring a greater range, a sigle engine, and the ability to carry an inboard radar.
    Dassault has forseen theses changes and decides to make new from old : he buys the half finished MD 550 n°2 prototype and fits her wings on a new fuselage built around an ATAR 101 engine.
 
 

   The new aircraft, built as a Dassault self venture, will be called "Mirage III. ( the Mirage II being the unaccomplished MD 550 02).This first and unique Mirage III makes its maiden flight on november 17th 1956. It is quickly nicknamed "Balzac", a joke relate to the "Jean Mineur" advertising whose call number was : Balzac 001.On january 30th, Serge Dassault, head of the flight test team rejoices : the Balzac has reached mach 1.52 in level flight.

The Mirages III A :

    In may 1957, the french air ministery orders 10 pre production Mirage III A, to be used as test plane for the first operational variant : the Mirage III C. These aircraft will be powered by the 6000 Kg dry thrust ATAR 9B. The fitst Mirage III A takes off on may 12th 1958 from the Meulun-Villaroche airfield, mach 2 will be reached in october and later mach2.2 (with the help of the SEPR rocket). Each airplane is intended for a specific task :

                    - III A-01 : flight envelope, aerodynamical tests.
                    - III A-02 : SEPR rocket tests
                    - III A-03 et 04 : controls
                    - III A-05 et 06 : Cyrano radar, new fin
                    - III A-07 à 09 : brakes, landing, gunnery, weapon stations
                    - III A-10 : operational trials at the CEAM Mont de Marsan