Shuttle in Orbit; Quickly Deploys Two Satellites

The space shuttle Discovery pushed safety guidelines to the limit Tuesday by thundering into orbit through a cloudy, rainy sky, and then quickly launched two satellites, one on an emergency basis.

The dual deployment in one day was a first for the shuttle. It became necessary when two hours into the flight the crew discovered that a sun shield designed to protect one of three communications satellites aboard the shuttle from thermal radiation was jammed.

Satellites rotate after they are released, constantly changing the surface that is exposed to the sun. But if left unshielded after the shuttle’s cargo bay doors are opened, the sun concentrates on upper surfaces, and temperatures fluctuate wildly, depending on shadows and the angle of the sun.

Sun Shield Snags

After the cargo bay doors were opened, the shield apparently snagged on something--possibly a camera that was in the wrong position on the elbow of the shuttle’s robotic arm--and was bent so severely that it was locked in a partially closed position. It could not be closed to protect the satellite, and it could not be opened to launch it.

Astronaut John M. Lounge, 39, used the robotic arm to force the shield open, and the National Aeronautics and Space Administration moved quickly to launch the satellite rather than let it cook in the cargo bay, which would have destroyed its electrical components in a matter of hours.

That called for some quick adjustments in the crew’s workload, since the satellite, owned by the communications arm of the Australian government, had not been scheduled for deployment until the second day of the flight.

Six hours and 35 minutes into the flight, the satellite, called Aussat-1, was released from the shuttle and began its seven-day trip to its permanent spot 22,300 miles above the Equator, where it will handle television and telephone service for the Australian continent.

Tracking data showed that the rocket fired perfectly.

“Fantastic,” Mission Control in Houston told the shuttle. “We all breathed a sigh of relief down here.”

A second satellite, owned by the American Satellite Co., which provides communications for 450 of the nation’s largest business and government agencies, was released five hours later, capping one of the stormiest launch days in the history of the shuttle program.

Robert Sieck, launch director at the Kennedy spaceport, conceded that NASA had pushed its regulations “to the limit” to permit the launch, but he insisted that no violations had been committed.

Launch Called ‘Marginal’

“Technically, it was within the limits,” Sieck said, “but realistically it was marginal.”

While it may have been within limits, no one here could remember a launch quite like it. Shortly after lifting off from the launch pad, the Discovery disappeared into a cloud.

“That cloud is black,” Discovery commander Joe Engle, 53, radioed.

Sieck conceded that the cloud was black, but he noted that it was only about 500 feet thick, and the shuttle soon emerged from the other side and roared on.

Although there did not seem to be much lightning in the storm, there was a lot of rain near the launch pad. NASA guidelines prohibit launches if there is rain at the launch pad because of fear of damaging the shuttle’s heat-protective tiles, and Sieck insisted that the pad itself was dry.

“I would put it (the rain) within two miles” of the pad, he said.

Within minutes after the launch, however, the entire area was engulfed with heavy rainfall.

NASA desperately wanted to get the launch off, which was delayed Saturday by weather that did not seem as bad, on the surface, as Tuesday’s, and the launch was scrubbed again on Sunday because of the failure of an on-board, backup computer.

Thursday Was Deadline

If the Discovery had not been launched by Thursday morning, NASA would have been forced to scratch the highlight of the mission--the attempted rescue of a Hughes Aircraft Co. satellite that has been drifting in orbit since it failed to activate itself last April. By Friday, that satellite would have drifted too far away from the orbit the Discovery must follow to release the three commercial satellites.

NASA is still trying to decide when to attempt that rescue. It could come as early as Saturday or as late as Monday, but officials were leaning toward Saturday.

Astronauts James D. van Hoften, 41, and William F. Fisher, 39, will go outside the Discovery to “hot wire” the satellite, thus permitting ground controllers to turn it on.

The fifth member of the crew, pilot Richard O. Covey, 39, will handle the Discovery as it maneuvers alongside the 15,000-pound satellite.

The Discovery is to land at Edwards Air Force Base in Southern California, but the date of the landing depends on when the rescue is carried out. The landing could come as early as Monday or as late as Wednesday.