Science: Slingshot for Jets

When aircraft carriers of the U.S. Navy make ready to launch their planes, they turn into the wind and steam at high speed. But even with a stiff breeze whipping across the flight deck, attack bombers and jet fighters often need a large and cumbersome catapult to boost them up to flying speed. And on a hot, calm day, the thrust of this giant slingshot is barely enough to toss them aloft.

This week H.M.S. Perseus, light (12,265 tons) carrier of the Royal Navy, was en route to Philadelphia, prepared to demonstrate a new catapult designed to handle hefty modern aircraft. The new catapult has been tested for more than a year. Weights, dummies, pilotless planes and finally regular carrier craft have been flung into the air at speeds up to 135 knots—fast enough for flight even when the ship is riding at anchor.

Heart of the new launcher is a slotted cylinder through which a piston is driven by high-pressure steam from the main boilers. Even during steady use, the large demand for steam does not interfere with operation of the ship's turbines. Nearly every type of Britain's newest carrier planes has been catapulted, and enthusiastic pilots report that the launching is an entirely new experience. "It eases you up so beautifully," said a U.S. flyer attached to the Fleet Air Arm, "that you almost forget you're being catapulted."

Because the powerful new catapult should often make it unnecessary for a ship to steam into the wind for long periods to get its planes away, the British Admiralty expects it to revolutionize naval air tactics. If it works as well with heavy U.S. attack bombers and torpedo planes as it has in tests with lighter planes of the Fleet Air Arm, it will be installed as standard equipment in carriers of the British, Australian and Canadian navies, may also be adopted by the U.S.