ZIL-2906 screw-propelled vehicle

The ZIL-2906 and its development the ZIL-29061 are screw-propelled amphibious vehicles (shnekokhod) from the ZIL special design bureau. Instead of wheels or tracks they have two long hollow cylinders with spiral blades along their sides. Turning the cylinders drives the vehicle through deep snow, soft sand, swamp and melting ice, and also floats and moves it in water.

Origins

The idea was first tried about four decades before the archive's source article, on the PEU-G (later SHN-1 or SHN-67) built under Vitaly Grachev. Its two steel screw rotors were 800 mm in diameter with blades set at 15.5 degrees, filled inside with about 100 mm of polyurethane foam for stiffness and buoyancy. The frame was a space frame of aluminium alloy, and the three-seat glassfibre cab was borrowed from the PEU-1. A 180 hp ZIL-375 engine in the middle of the frame drove the rotors through a hydromechanical gearbox from the ZIL-135L, final drives from the K-61 tracked transporter and reversing gears, so each rotor could turn either way. Kerb weight was about 3 tonnes with a payload of 1.5 tonnes, and it did very well in tests on swamp, deep snow, floating debris and mud.

In service

The ZIL-29061 became the third vehicle of the ZIL-4906 Blue Bird search-and-rescue complex. It was carried on the cargo vehicle and unloaded near the landing site to reach the cosmonauts over ground the wheeled vehicles could not cross. Its fuel lasted about four hours, or roughly 100 km on snow. One was later tried out for cutting reeds in fish ponds in the Astrakhan region.