Science: Back to Earth

When scientists send up research rockets to probe the thin upper atmosphere, they generally kiss their instruments goodbye. Few scientific gadgets survive the impact when the spent rocket hits the earth at thousands-of-miles-per-hour speed. Ordinary parachutes are no help because they are generally torn to shreds before they can waft the instruments to earth.

This week General Electric Co. described something called a “rotochute,” developed by Engineer I. B. Benson, to help bring rocket instruments safely back to the ground. It looks like a stocky arrow with two propeller-like blades hinged to the bulbous head that holds the instruments.

The rotochute is carried inside the rocket with the blades folded back. Blown free at the top of the rocket’s trajectory, it falls rapidly in the near-vacuum 60 to 100 miles up. When it reaches the denser atmosphere below, it straightens out and begins to revolve. The blades open. Spinning like a maple seed, the rotochute slows down and lands its load of instruments at a safe 27 m.p.h.