US space shuttle mission unsettles Moscow; Shuttle's last test: 225 m.p.h., 3-point landing

They work under different banners -- the silver team, the crimson team, and the bronze team. To them the space shuttle Columbia is a technological wonder best explained in acronyms: the OMS (orbital maneuvering system) provides thrust to move from one orbit to another; the RCS (reaction control system) helps the shuttle change attitude; the SRBs (solid rocket boosters) helped put the vehicle in orbit.

Dutifully, these flight directors have reported the status of the mission in technical detail as they await the shuttle's 225 mile-an-hour touchdown on a dry lake in southern California on Tuesday.

Yet toward the end of Columbia's 54 1/2 hour maiden flight, they all were beginning to sound a similar and more readily understandable theme: Columbia had worked "textbook perfect" and with a successful reentry and landing, scheduled for April 14, the nation's newest manned space program may turn past delays on their head and proceed faster than expected.

The Collumbia's first flight is to be followed by three more test flights before the shuttle is considered operational in the fall of 1982. The schedule is not apt to change, but the testing on the missions could be expanded.

After assessing the overall performance of the Columbia through launch and orbit, Gene Kranz, deputy director of flight operations here, said, "We have the capability of moving into a more aggressive flight program; procedurally everything is going right."

"It's amazing we've just not had anything that is a real problem," agreed another flight director here at mission control.

Still, the optimistic view of a more aggressive shuttle program first requires clearing a major hurdle. The Columbia must be brought back to Earth safely -- a task considered one of the most difficult aspects of the flight. And it is made more uncertain by the loss of some of the shuttle's protective coating of silica tiles.

Landing the Columbia at Edwards Air Force Base, Calif., will be a dramatic maneuver. The shuttle will decelerate during orbit by firing thrusters to reduce its 18,000 m.p.h. speed. The nose of the vehicle will be high as it lowers through Earth's atmosphere. Some parts of the vehicle will reach 2,600 degrees F.

Aside from the heat, the aerodynamics of flying a winged vehicle at the great speeds the Columbia will reach coming into Earth's atmosphere are basically unknown.

The crew will have more manual control of the shuttle during reentry and landing than at any other phase of the flight. They will operate steering control, but the shuttle's computer system will interpret their maneuvers and tell the Columbia how to respond. "The crew becomes a valuable piece of information to the computer because they can see out their windows," explained one NASA official.

The trajectory of the landing is at an angle about eight times steeper than that of a conventional commercial aircraft. And the Columbia will slow to a linding speed of 225 m.p.h. -- twice the speed of a commercial aircraft at touchdown. One NASA official said compared with other aircraft the shuttle "drops out of the sky like a rock."