Russian experts try to fix space station computers

MOSCOW, June 15 (Reuters) Russian engineers sought to fix malfunctioning navigational computers on the orbiting International Space Station today, hoping to ward off a possible evacuation of its three crew.

The computers, some of which control thrusters that help keep the 100 billion dollar station in a stable orbit, broke down on Wednesday shortly after the crew of the visiting US space Shuttle Atlantis installed a new solar wing panel for power.

Russian space officials were ''cautiously optimistic'' the problems in the German-built computers that run Russian software could be solved, a Roskosmos official was quoted as saying.

The six computers were restarted yesterday and worked for three hours before breaking down again, Russian media reported.

''During the day a whole series of measures will be undertaken to analyse the reasons for the malfunction of the computers and to get them back in working order,'' Russian space agency spokesman Igor Panarin told the Interfax news agency.

''We're cautiously optimistic about solving this problem.'' Officials at mission control outside Moscow declined immediate comment but planned to hold a news conference later today.

NASA has said that a failure to fix the computers could force a temporary evacuation of the space station, a 16-nation project which has been continuously manned since Nov. 2, 2000.

That unlikely worst-case-scenario would entail the three space station astronauts leaving in the escape ship, a Russian Soyuz capsule. The Atlantis crew would return to Earth on the shuttle.

The station mainly relies on big gyroscopes to maintain its proper orientation in space but also uses control jets and navigation systems run by the computers in its Russian section.

No cause for the problem has been established but a leading theory cited by Russian officials has been electronic ''noise'' caused by magnetic fields from nearby cables that may have increased once the new solar panel was attached.

REUTERS SLD KP1559