The Super Rotor AC.4 Andorinha ("Swallow") was a sport autogyro first produced in Brazil in the 1960s.[1] The prototype was built by Altair Coelho and flown in 1960 as the AC.1,[2] a typically minimalist autogyro design consisting of an open framework supporting the pilot's seat, rotor mast, engine mounting and tail fin.[3] Power was supplied by a converted Volkswagen engine driving a pusher propeller.[3] Francisco Mattis purchased the prototype and manufacturing rights and founded Super Rotor (now Montalva) of São Paulo to produce the aircraft.[3] Refinements for serial production as the AC.4 included an extra reinforcing strut for the rotor mast and a larger tail fin.[2] According to Altair Coelho, the AC.4 first flew in 1964, and gained type approval and certification in 1972. 314 were built.
Super Rotor went on to produce a two-seat version with dual controls as the M.1 Montalva,[1] [4] a turbo-charged two-seater as the M.2 Trovão Azul ("Blue Thunder"),[4] and an agricultural version with spray bars as the Agricóptero.[4]