Science: Capsule to Earth

"For an hour and a half," said a high Pentagon scientist last week, "the man in the satellite isn't going to know whether the re-entry system really works. That's why we need a test-pilot type—daredevil but stoic." The first stoic satellite daredevil has not yet been picked, but last week the National Aeronautics and Space Administration signed a contract (see BUSINESS) for the hollow, upholstered meteorite in which he will ride.

The U.S. program to put a man in orbit and bring him back alive, called Project Mercury, is distinct from the tests scheduled for the stub-winged X-15 already built by North American Aviation. Inc. Essentially an extra-tough airplane, the X-15 will climb into nearby space under its own rocket power and glide quickly back to earth under full control. Project Mercury's space capsule will be designed to achieve an around-the-earth orbit, but it will land passively by parachute.

Padded Couch. The capsule will be launched by an intercontinental ballistic missile (presumably an Atlas or its successor). The pilot will lie on his back on a padded couch to reduce the effects of g forces, reckoned to hit more than seven times the force of gravity during the acceleration after takeoff. In his tiny enclosure, he will be surrounded by an atmosphere of endurable temperature and pressure. He will have food and water in case he feels like eating or drinking, and a two-way voice radio will keep him in touch with the ground stations. There will be no window for him to look out, but an "optical display" (undetermined) will give him a kind of indirect visibility. If anything goes wrong early in the ascent, he can fire an escape rocket that will bring him back to earth, with luck, before he has climbed too high.

Except for peeks at the optical display and conversation with the ground, the pilot will have little to do in his orbit around the earth. An automatic attitude sensor will operate the gas jets that keep the capsule from rolling. Then, at a signal from the ground or from the pilot himself, the jets will somersault the capsule, turn it so that its retrorockets can fire and slow its speed.

This will be the critical moment. As its orbital speed decreases, the man-carrying satellite will curve downward into the atmosphere. The capsule will hit the thin upper air at almost 18,000 m.p.h.—enough energy of motion to turn capsule and pilot into incandescent vapor unless it is dissipated effectively. To ground watchers, the capsule will flare like a shooting star, leaving a broad track of flame in the sky. The pilot is expected to feel, for a brief period, about 10 g of deceleration.