The Savoia-Marchetti SM.75 Marsupiale (Italian: marsupial) was an Italian passenger and military transport aircraft of the 1930s and 1940s. It was a low-wing, trimotor monoplane of mixed metal and wood construction with a retractable tailwheel undercarriage. It was the last of a line of transport aeroplanes that Alessandro Marchetti began designing in the early 1930s. The SM.75 was fast, robust, capable of long-range flight and could carry up to 24 passengers for 1,000 miles. The SM.75 was designed in response to an enquiry from the Italian airline Ala Littoria, which was seeking a modern, middle-to-long-range airliner and cargo aircraft as a replacement for its Savoia-Marchetti S.73 aircraft. Savoia-Marchetti chief designer Alessandro Marchetti (1884–1966) retained the general configuration of the S.73 but introduced retractable main landing gear to reduce aerodynamic drag. The SM.75s airframe consisted of a steel-tube frame with fabric and plywood covering, and its control surfaces were plywood-covered. The SM.75 had a four-man crew, and its cabin was built to accommodate up to 25 passengers. Its short take-off run of 337 metres (1,105 feet) and shorter landing distance of 280 m (920 ft) meant that it could operate from short runways on secondary airfields. The SM.75 was powered by three 559 kW (750 hp) Alfa Romeo 126 RC.34 radial engines. Eleven aircraft fitted with three 641 kW (860 hp) Alfa Romeo 126 RC.18 14-cylinder engines were designated SM.75bis. The Regia Aeronautica (Italian Royal Air Force) was interested in the SM.75, resulting in the development of a militarized version. This had much smaller cabin windows and was reinforced for a dorsal gun turret, as well as being equipped with a retractable bomb aimer's cupola, and a bomb bay. It was powered by three Alfa Romeo 128 RC.21 engines and had a greater cargo capacity than the SM.75, and entered military service as the Savoia-Marchetti SM.82. In 1939, a floatplane version of the SM.75 was built as the SM.87, powered by three 746 kW (1,000 hp) Fiat A.80 engines. It could reach a speed of 365 km/h (227 mph), had a ceiling of 6,250 m (20,510 ft), and a range of 2,200 km (1,400 mi). With a crew of four, it could accommodate 24 passengers. Four were built. For more information on operational history and variants, click here.
