Stridsvagn 103

The Stridsvagn 103, or S-tank, is a main battle tank with a crew of three who sit entirely inside the hull. Several of the archive photographs show it fitted with a collapsible flotation screen around the hull, raised like a bellows to let the tank swim.

Engines

Its most unusual feature is a pair of engines. The main engine was originally a six-cylinder Detroit Diesel. A secondary Boeing Model 553 gas turbine of 490 hp provided extra power in combat and helped with starting in cold weather. Together the two gave performance comparable to tanks with bigger, thirstier single engines.

From 1984 all Strv B tanks were upgraded to Strv C standard, and as part of that programme the Detroit Diesel was replaced by a Rolls-Royce K60 diesel. Both engines are mounted at the front, which adds protection for the crew.

Swimming

The archive pictures include views of the screen folded down and raised, a tank afloat, and examples displayed at public events in Belgium in 2004.