The Aeronautica Umbra S.A. of Foligno was established in 1935 by Muzio Macchi, and was primarily concerned throughout the war years with sub-contract work for other aircraft manufacturers. Umbra built Savoia-Marchetti S.M.79 torpedo-bombers under licence. However, Aeronautica Umbra's design office, which was responsible for the unsuccessful T.18 single-seat fighter of 1938, designed by Dr. Ing. F. Trojani, did undertake some original work, and a heavy fighter of advanced and unorthodox design, the M.B.902 designed by Ing. Bellomo, was actually built, although flight testing had not commenced when the prototype was destroyed.
The construction of the M.B.902 was begun in 1942, and this single-seat fighter was unusual in being powered by a pair or 1,250 h.p. Daimler-Benz DB 605 liquid-cooled engines buried in the fuselage and driving twin contra-props mounted outboard on the wings via extension shafts. Featuring a retractable nose wheel undercarriage and carrying an armament of four 20-mm. and two 12.7-mm. guns, the M.B.902 had an estimated maximum speed or 429 m.p.h., and a maximum range of 1,056 miles.
Postwar production comprised aircraft and systems components until work was begun, in 1968, on the AUM-903 three-engined STOL light transport project. Production concentrated on licence manufacture of the Scheibe SF-25B Motorfalke motor glider for the Italian and North African markets.