What propulsion system does the Soviet PT-76 use for swimming?

The Soviet PT-76 uses water jets for swimming. Two hydrojets, mounted on opposite sides of the hull, draw in water beneath the tank and expel it through outlets at the rear.

The PT-76 was designed as a floating reconnaissance tank, entering Soviet service in the early 1950s. Its flat, boat-shaped hull and hollow road wheels helped provide buoyancy, while electric bilge pumps removed water that entered the vehicle. A folding trim vane at the bow improved stability and reduced the chance of flooding.

The hydrojets also helped the tank maneuver. Closing or redirecting an outlet allowed the driver to turn, reverse, or even pivot the vehicle. The tracks were essential for movement on land but were not the primary swimming drive, and the tank did not use boat-style propellers or an outboard motor.

The same basic water-jet arrangement was later used on the BTR-50 amphibious armored personnel carrier, whose chassis was derived from the PT-76.