March 1981:a description of STS-1

After long delays, suddenly the Space Shuttle “Columbia” has reached the launch pad at the Kennedy Space Center and is being checked out ready for its maiden flight. Huge crowds are expected to gather to witness the launch as millions of people around the world watch events live by television.

It was on 24 November 1980 that the stubby winged craft was transferred from the Orbiter Processing Facility to the Vehicle Assembly Building where, two days later, it was mated with the External Tank and Solid Rocket Boosters on the Mobile Launch Platform.

A series of checks began with the Mobile Platform lift-off umbilicals and the External Tank tumble system; and the Orbiter’s inertial measuring unit was calibrated. The Orbiter’s main engine nozzles were gimballed and aerodynamic control surfaces - elevons, rudder/speed brake and body flap - were moved to check clearances. Tests were also made of the ability of the Orbiter’s on-board computers to steer the Solid Rocket Boosters during the ascent into orbit. The boosters are steered by hydraulically moving the nozzles.

Then the spacecraft was powered up and its complex systems put through the most rigorous testing with the flight crew and mission control personnel taking part. Prime crew astronauts John Young and Robert Crippen, and backup crewmen Joe Engle and Richard Truly, participated in flight simulations which included ascents to orbit, return to launch site and single orbit aborts, and descents from orbit to landing.

It says a great deal for the efficiency of the hard-worked space teams that the bulk of the work was completed ready for the whole stack to be moved by the giant crawler to Launch Complex 39A so soon after Christmas. Then began 10 weeks of further tests including preparation for a critical 20 second firing of the Orbiter’s three main engines on the pad. Mission and launch verification tests on the pad were being followed by countdown demonstration tests and,if all is well,pre-launch checkout begins at T-minus 120 hours.

In view of the advanced nature of the project, it would be surprising if there were no hidden snags in this procedure. It was already clear that the earliest launch date of 14 March would be exceeded but, all the same, solid progress had been made. The actual lift-off - when it comes - will proceed as follows:

Min/Sec

-00.07 Space Shuttle Main Engines start

00.00 Solid Rocket Boosters ignite. Lift-off.

00.07 Vehicle clears tower.

00.52 Maximum dynamic pressure.

02.05 SRB’s separate.

08.42 SSME’s shut down

08.59 External Tank separates

10.43 Manoeuvring engines ignite to put spacecraft into orbit.

Much attention has been paid to emergency drills in case of engine problems after lift-off. Depending on the circumstances, the spaceplane would burn two of the three main engines for a longer period if one failed, or a decision could be made to return to the Cape. In the latter case, the vehicle must make a 180° turn and ditch its tank. The astronauts seem confident that such drastic action will not be necessary.

Young and Crippen expect to remain in orbit for just over two days making checks of on-board systems in conjunction with Houston Mission Control where use will be made of the same consoles that were brought into operation for the Apollo Moon landings. However, the computers, video displays and communications systems have been updated and now permit operations to proceed with fewer flight controllers. The new system of communications includes more than 1,000 video formats each of which can present up to 250 parameters.

The astronauts have special tasks to perform in orbit besides monitoring their equipment. One involves opening and closing the Orbiter’s huge cargo bay doors. Inside the doors are radiators which must be exposed in any flight lasting more than a few hours to disperse waste heat. Young and Crippen have been practicing emergency EVAs in the large water tank at the Johnson Space Center.

The astronauts approach the re-entry procedure with the same equanimity. At entry interface the Orbiter will be moving at a speed of 28,500 km/h some 122 km above the Earth pitched up at 30° and descending at a shallow angle. Six minutes and 10 seconds later it will begin to pick up maximum heating. The period of maximum temperature must be endured for nine minutes, but the special silica insulation tiles that protect large areas of the spaceplane shed heat so readly that one side of the material would be cool enough to hold in bare hands while the other side is red hot.

At 28.18 after entry interface the pilot takes manual control heading towards the airstrip at Edwards Air Force Base,California. At 30.38 the undercarriage is lowered and the spaceplane touches down at 30.56. Although “Columbia" has been fitted with an automatic microwave landing system, this will not be used on the first few flights.

Astronauts Young and Crippen, who began training for the mission in January 1978, say they expect the flight to follow the work they have done on the moving base and fixed base simulators at Houston very closely. In the last month they have been putting in an eight hour week in each simulator in turn.

Target date for the start of formal operation of the Space Shuttle - following four orbital test flights - is the fifth flight of “Columbia” in September 1982, when the first Tracking and Data Relay Satellite will be launched. The operational schedule during the first four years calls for 74 flights, of which 64 will be from the Kennedy Space Center and 10 from Vandenberg Air Force Base. The second Space Shuttle “Challenger" is scheduled to make its maiden flight in November 1982. “Discovery" and "Atlantis", the remaining shuttles, are expected to fly in December 1983 and January 1985 respectively.