Russian Cosmonauts Bypass Power Switch

Russian space engineers Fyodor Yurchikhin and Oleg Kotov revived the computers onboard the International Space Station Friday, bringing what must have been great sighs of relief to those onboard, and controllers at Johnson Space Center and in Russia.

The Russian flight controllers and the station crew were able to power-up two lanes of the Russian Central Computer and two lanes of the Terminal Computer by using a jumper cable to bypass a faulty secondary power switch, reported NASA.

Flight controllers began sending commands Friday night to restart some systems. The central computer is now communicating with the US command and control computer, and the terminal computer is communicating with US navigation computers. The plan calleded for more system restarts Saturday.

The Russian navigation computers provide backup attitude control and orbital altitude adjustments. For now, the station's control moment gyroscopes are handling attitude control, with the shuttle's propulsion system providing backup.

As ANN had reported, the computer crash four days ago had restricted oxygen production and navigation.

NASA had instructed astronauts Thursday to shut down non-critical electronics onboard Atlantis, including cameras, laptop computers and lighting equipment, to conserve energy, in case officials determined the shuttle would remain docked to the station for another day to help with the situation.

The computers came back up at 4:09 New York time, said NASA spokeswoman Lynette Madison. The computers were then temporarily shut down for maintenance work, reported Bloomberg.

The computers crashed after the crew of the US space shuttle Atlantis added solar panels to the space station.

The shuttle had the ability to serve as a navigational backup and the outpost had about 55 days of oxygen reserves. Officials say the situation could still alter plans for the return Atlantis, reported Voice of America.

ISS Mission Manager Mike Suffredini explained that the problem was a faulty circuit inside the computers, which Russian technicians were able to bypass.

"They went to activate the four that they thought were still good, and all four of the computers came up," he said.

Suffredini said the other computers are still inactive, and he expects they will be sent home aboard Atlantis. But if everything looks good with the operating computers, Suffredini said they will begin slowly activating all of the systems on board the space station Saturday.
 
Officials said the most important system maintains the space station's position, or attitude, in orbit.

Suffredini said mission controllers probably will not know for another day or two whether the computers can maintain attitude control. If not, Atlantis will remain docked to the space station to keep it stable by firing its thruster rockets, something that would delay the shuttle's return.

Suffredini is cautiously relieved by the turn of events. He had said from the start of the crisis that no one intended to abandon the space station, even if the inhabitants had to be rescued because of the failed computers.

"When the crew said they were up and running, even before anything else was said, or any time passed, when two of them (computers) came up and stayed up together, I knew we had changed something for the better," said Suffredini.

"And at that point, there's a little bit of relief, because you know some of the [contingencies] you're working on, hopefully you won't have to go try implement."

Friday during a space walk, shuttle astronauts also successfully repaired a torn thermal blanket, designed to protect the shuttle from the heat of re-entry when it returns to Earth next week.

The space station, which has an American portion and a slightly smaller Russian one, has a crew of three in addition to the visiting seven Atlantis astronauts. It orbits about 240 miles above Earth.

FMI: www.nasa.gov