A problem that worries the designers of jet bombers and airliners is how to make them stop quickly enough on short or slippery runways. Propeller-driver ships merely change the angle of their propeller blades and use the reversed thrust to kill their speed. A jet has no propeller, and a drag parachute broken out of the tail in the landing run is a cumbersome solution.
This week Boeing Airplane Co. told about its experiments with certain gadgets to reverse the thrust of a jet engine. The type that finally worked best for Boeing is a divided, clamshell-like contraption that normally fits snugly...