Origins On 13 July 1934, the
Service Technique Aéronautique (Aeronautical Technical Service) of the
French Air Force issued the "C1 design" requirement for a new and modern single-seat
interceptor fighter. The design team, headed by Maurice Roussel, was assembled at Bloch's
Courbevoie facility in
Paris. Although the C.1 competition was won by a rival design, the
Morane-Saulnier M.S.406, it was decided independently to continue with development. During 1936, these efforts culminated in the first attempted flight of the
MB.150.01 prototype; unfortunately, the aircraft proved unable to get off the ground. Amidst the disappointment, work on the design was temporarily halted and then resumed during early 1937. As a result of the CEMA flights, the performance of the prototype was sufficiently interesting as to warrant further development. This brought, at the beginning of 1938, a small increase in the aircraft's wing span, the replacement of the twin wing-mounted
radiators by a unit installed between the wheel wells, and the installation of an improved 14N-7 engine, which led to the prototype being re-named
MB.150.01M (
M standing for
modified).
Further development There was no direct production of the
MB-150.01 as the aircraft having been deemed to be unsuitable for mass production. Amongst other changes needed, the structure of the airframe had to be redesigned to suit mass production. During early April 1938, an order was received for three more prototypes; these were to explore the possibilities for installing more powerful engines of both French and American design, such as the
Hispano-Suiza 14AA,
Pratt & Whitney R-1830 Twin Wasp, and further derivatives of the
Gnome-Rhône 14N engine. This design effort led to the production of the
MB.151.01 and
MB.152.01 prototypes, which were developed and produced in parallel. According to Christesco, the MB.152.01 was "the first true aircraft" of the series. This model was equipped with a more powerful
Gnome-Rhône 14N-21 engine, capable of a speed of and equipped with a revised armament arrangement. On 15 December 1938, the MB.152.01 prototype performed its maiden flight. The manufacturing of the fighter was divided amongst the various branches comprising SNCASO. Under the terms of the armistice, the remaining 25 on the production line were completed and delivered into
Vichy service. From there, some eventually made their way into the
Luftwaffe after 1942. The final member of the family, the
MB.157 had a far more powerful engine and eventually became a very different aircraft as the design evolved from the MB.152 to accommodate the larger and heavier
Gnome-Rhône 14R-4 motor. Unfinished at the time of the armistice, it was ordered to be completed and flown under German supervision. Demonstrating superb performance, it was taken to
Orly where the engine was removed for testing in a
wind tunnel. The excellence in the design was confirmed by Germans when they completed and tested it in 1942, reaching up to . It was later destroyed in an
Allied air raid. ==Operational history==