On the flipper side
A boat powered by flippers, rather than a propeller, is being developed by the Massachusetts Institute of Technology, USA. The system, based on the swimming action of the penguin, uses two motor-driven flippers, thereby saving fuel and energy, claim the developers. The flippers are designed to produce the same hydrodynamics as the tail of a tropical fish. The flippers flap 30 times per minute and can propel a 300-fect boat at speeds up to 30 knots. The developers of Proteus, a 12-feet-long boat with two oscillating foils, or flippers, attached to its stern, say it is the forerunner of ftffi-scale flipper-propelled ships (Engineering Designer, March 1997).