Outpost on a new frontier

ORBITING BEEHIVE of activity, a space station on NASA’s draw­ing board serves as a staging point between shuttle flights 200 to 300 miles above the earth and satellites at higher altitudes. A manned orbital transfer vehicle (1) returns from servicing communications platforms in a 22,300-mile-high geostationary orbit. Later it will boost a deep-space relay satellite under construction (2) to a similar orbit. A crew of eight is quartered in two living modules (3) powered by two 50-kilowatt solar ar­rays (4).

earth and satellites at higher altitudes

Supplies for 180 days are stored in a logistics module (5). Pre­paring to dock, a shuttle readies its manipulator atm (6) to unload a California, we were doing Mach 7 and I could pick out Monterey Bay. We were about to enter the most uncertain part of our flight. Up to this point, Columbia’s course was controlled largely by firings of its re­action control thrusters. But as the atmo­sphere grew denser, the thrusters became less effective. Columbia’s aerodynamic con­trols, such as its elevons and rudder, began to take over.

 

We had more and more air building up on the vehicle, and we were going far faster than a winged vehicle had ever flown. More­over, the thrusters were still firing. It was an approach with a lot of unknowns. Wind tunnels just cannot test such complex aero­dynamics well. That was the main reason John took control of the flight from the auto­mated system at a little under Mach 5.

We had been doing rolls, using them a little like a skier uses turns to slow and control descent down a mountain. The flight plan called for John to fly the last two rolls manually. He would fly them more smoothly than the auto­matic system, helping to avoid excessive side slipping and ensuring that we would not lose control as we came down the middle of our approach corridor.