Aerosan

An aerosani (Russian: aэросани, aerosani, literally 'aerosled') is a type of propeller-driven snowmobile, running on skis, used for communications, mail deliveries, medical aid, emergency recovery and border patrolling in northern Russia, as well as for recreation. Aerosanis were used by the Soviet Red Army during the Winter War and World War II.

The first aerosanis may have been built in 1903-05 by Sergei Nezhdanovsky. In 1909–10 young Igor Sikorsky tested self designed aerosani, before he built multi-engine airplanes and helicopters. They were very light plywood vehicles on skis, propelled by old airplane engines and propellers.

Military use of the aerosani goes back to at least the 1910s. During World War I, aerosanis were found to be useful for reconnaissance, communicating and light raiding in northern areas. During the 1939–40 Winter War against Finland, some were equipped with a machine-gun ring mount on the roof. They could carry four to five men, and tow four more on skis. The aerosanis were initially used for transport, liaison, and medical evacuation in deep snow, and mostly used in open country and on frozen lakes and rivers because of their poor hill-climbing ability and limited maneuverability on winding forest roads.

During World War II, aerosanis were found to be useful for reconnaissance and light raiding in northern areas, thanks to their high mobility in deep snow (25–35 km/h, where many vehicles couldn't move at all). Responsibility for aerosanis was transferred to the Soviet Armoured Forces (GABTU) and orders were submitted for design and fabrication of lightly armoured versions, protected by ten millimetres of steel plate on front. They were organized into transport or combat battalions of 45 vehicles, in three companies, often employed in co-operation with ski infantry. Troops were usually carried or towed by transport aerosanis, while fire support was provided by the heavier machine gun-armed, armoured models. Aerosanis were not used for direct assault because of their vulnerability to explosives such as mortar rounds.

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Wikipedia