US spacewalkers overcome glitch on 200th station outing

Cape Canaveral: Two U.S. astronauts overcame an early equipment glitch to complete an abbreviated spacewalk outside the International Space Station on Friday, accomplishing all the major tasks initially planned for a longer excursion in four hours, NASA said.

Station commander Peggy Whitson and rookie flier Jack Fischer began what was expected to be a 6-1/2-hour spacewalk more than an hour late, after a cable supplying power and cooling water to Fischer`s spacesuit developed a leak.

The spacewalk was the 200th outing in support of station assembly and maintenance since construction of the $100 billion laboratory, which flies about 250 miles (400 km) above Earth, began in 1998.

Fischer ended up sharing Whitson`s spacesuit servicing system, which caused both to burn through their spacesuits` battery power faster than usual. That prompted the U.S. space agency to shorten the outing and assign the astronauts just one task.

The pair breezed through their first priority, replacing a faulty, 200-pound (90 kg) electronics box that routes commands and data to experiments. With time to spare, they then tackled chores slated for the original spacewalk, including installing a cable to troubleshoot a cooling system problem with the station`s $2 billion dark matter detector, mission commentator Rob Navias said.

They also attached a debris shield onto an exposed docking port that is being prepared for commercial space taxis under development by Space Exploration Technologies, or SpaceX, and Boeing Co .

It was Fischer`s first spacewalk, and the ninth for Whitson, who last month broke the record for cumulative time in orbit by a U.S. astronaut.

"All of the major work has been accomplished," Navias said. "It`s been an highly successful spacewalk in spite of a somewhat uncertain beginning."