Computer error increased gravity load for spacemen's return

STAR CITY, Russia -- A computer error is suspected of sending three spacemen on a wild ride home that was so steep and forceful their tongues rolled back in their mouths and they could hardly breathe.

Then antenna problems blocked their ability to announce a safe arrival, albeit one that was far short of the targeted touchdown site. Even so, the two astronauts and one cosmonaut who returned to Earth Sunday from the international space station were in good spirits Tuesday as they talked about their adventure.

American Donald Pettit, the sickest and weakest upon return, didn't mind having a few more hours alone with his crewmates after 161 days together in orbit. He had been warned about the "mob scene" and "hustle and bustle" awaiting him in Kazakhstan, what with all the recovery helicopters.

"I was actually relieved to ooze out of the spacecraft and lay on Mother Earth and have a solitude moment in which to get reacquainted," Pettit said, reflecting on his historic yet harrowing ride. They had landed nearly 300 miles off-course.

All three were crawling on their hands and knees the first hour and a half, said cosmonaut Nikolai Budarin, who popped open the hatch and was the first one out.

The transition from weightlessness to gravity was made all the more difficult by the steeper descent that subjected them to eight times the force of gravity. That's twice the usual amount for a Soyuz and three times the load experienced aboard a shuttle.

"It was easier than I thought it was going to be, but there's a lot of pressure on your chest," space station commander Kenneth Bowersox said at a news conference. "It's hard to breathe and your tongue sort of slips back in your head and toward the back of your throat."

Pettit said, "For me, for a moment, it felt like I was Atlas and I had the weight of the whole world on my shoulders."

A cosmonaut whose own Soyuz landing two years ago was steep but not ballistic, Talgat Musabayev, said Russian space experts believe the problem was caused by software in the guidance computer installed in the new model Soyuz. It was the first time the modified spaceship had been used in re-entry.

If software is the problem, it should be an easy repair and the two new residents of the space station should have nothing to fear when they ride a Soyuz capsule back to Earth this fall. Flight controllers would develop a software patch and simply beam it up.

NASA is relying on the Soyuz for as long as the shuttle fleet remains grounded in the wake of the Columbia disaster. A severe Soyuz problem could easily shut down the orbiting complex.

Budarin, who was in charge of the Soyuz descent, told reporters neither he nor his crewmates did anything that would have caused the guidance computer to switch from a normal to ballistic descent. No NASA astronaut had ever returned to Earth in a foreign spacecraft before.

"It's for the specialists to figure out what was the cause," Budarin said. "Let's wait and see, but now I can say that it was not our own doings."

Bowersox, a former test pilot who assisted Budarin, agreed, but acknowledged, "You just never know for sure."

"In these types of situations, everything happens fast, sort of a blur, and it's best not to be too positive," he said. "The tape recorders are much better at analyzing the truth than the humans are."

Budarin explained why no one heard from the crew during the final minutes of the descent and for two full hours afterward. Several parachute cords, including one with an antenna, ripped off during descent. Two other antennas did not open at touchdown, and one opened toward the ground.

The men tried to use the NASA radio station, but it was too weak, Budarin said. Then they pulled out another antenna and used it to communicate with the rescue airplane that finally found them. Between their frail condition and the need to keep crawling back into the capsule, "it all took time," he said.

Bowersox and Pettit will spend another two weeks recuperating at the cosmonaut base in Star City, outside Moscow. Then they will fly home to Houston with their wives, who beamed with pride at the news conference.

Pettit said being tall and skinny, and a first-time space flier, has made his transition to gravity harder than his colleagues.

"I've had a little more trouble walking around than others," said the 165-pound 6-footer. Wife Micki said he came back 10 pounds lighter.

After all the drama on Sunday and the joyful reunion that followed, "the fog is sort of lifting out of my head," she said.

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