After the end of World War II, the Soviets devoted a considerable amount of effort to developing heavy transport gliders to deliver troops during an airborne assault. As part of this effort, the Council of Ministers ordered the Ilyushin design bureau on 20 September 1947 to begin work on a glider capable of carrying 7000kg (15,000lb) of cargo, including 60 troops or a 122mm cannon with its prime mover, ammunition and crew. Its intended tug was the Tupolev Tu-75, a four-engined transport derived from the Tupolev Tu-4.[1]
The Il-32 was an aluminum-bodied,[2] high-wing cantilever monoplane with a fixed tricycle undercarriage whose fuselage was square in cross-section to fit as much cargo as possible. The two-spar wings had a moderate aspect ratio. It was regarded as expendable and was built very simply to facilitate large-scale manufacture. The nose and tail sections swung up to 95° to starboard to facilitate loading.[3]
The Il-32 made its first flight on 20 August 1948, towed by a twin-engined Ilyushin Il-12, but the Il-12 was not powerful enough to tow a fully loaded glider and the four-engined Il-18 airliner prototype was adapted to tow it from 20 September. During these flight tests it reached a cruising speed of 323km/h at an altitude of and a weight of 16000kg (35,000lb). The flight tests were satisfactory and preparations were made to begin series production, but the lack of suitable tugs was a problem. None of the Soviet four-engined aircraft that could be used were either in production or available. Both the Tupolev Tu-70 and Il-18 airliners had been canceled, as had the Tu-75 transport, and the Tu-4 was dedicated to the strategic bombing mission. Experiments were made with a pair of Il-12s towing the Il-32, but this was both difficult and risky for all involved. The Il-32 was therefore canceled for lack of a proper tug.[3]