Formed 1935 at Bordeaux-Merignac by the Potez group when it took over the Societe Aerienne Bordelaise. Was intended as a decentralized production source for Potez and Bloch aircraft. A prime responsibility was development and production of Bloch types, especially single-seat fighters derived from MB.150 of 1936. Redesign facilitated production and improved performance, resulting in MB.151 and 152. By June 1940 production totaled about 600, involving five plants. MB.175 twin-engined bomber was in production and was revived after Second World War as torpedo aircraft. Several other prototypes built, including four-engined bomber.
In France, the Socialist Government of the so-called Popular Front brought all the companies building military aircraft, aero engines and armament under its control in 1936. The immediate result was the socialized oblivion of such established companies as Marcel Bloch, Bleriot, Nieuport, Potex, Dewoitine, Hanriot and Farman within half a dozen nationalized groups or Societies Nationales, named according to their geographical location (Nord, Ouest, Centre, Midi and so on).
Incorporated in SNCASO 1936, incorporating the factories of Marcel Bloch, Bleriot and Liore et Olivier, subsequently merging with SNCASO and changing name to Ouest Aviation in 1956.
In 1942 completed forerunner of Bretagne twin-engined transport, though not flown until 1945; then used commercially and experimentally. Numerous and varied post-Second World War types included distinctly unusual forms of rotary-wing aircraft. Aeriel (1948) and Djinn (1953) with tip jets, and Farfadet convertiplane (1953).
Aerocentre went into liquidation during 1949, its plants and work being shared by SNCAN (Nord), SNCASO (Sud-Ouest) and engine form SNECMA.
Original designs included S.O.94R twin-engined trainer; S.O.95 Corse, and S.O.30 Bretagne military transports; S.O.4050 Vautour twin-jet bomber; and the S.O.9000 Trident. The S.O.1221 Djinn two-seat helicopter was produced, and Vertol H-21 helicopters were manufactured under license for the French Army. Ouest became part of Aerospatiale.
After World War II, although four of the nationalized groups continued operating un-der state control, private companies were allowed to resume the design and manufacture of both civil and military aircraft. Some of the pioneering names of French aviation, such as Breguet and Morane-Saulnier, returned to prominence, and by 1950 a new one had been added - Avions Marcel Dassault.
Loire-Nieuport joined SNCASO in 1942.
SNCASO and SNCASE joined to form Sud-Aviation in 1958.