Extended EVA: Astronauts Make ISS Repairs in Long Spacewalk
Expedition 13 flight engineer Jeff Williams (lower left) and station commander Pavel Vinogradov work with the Strela hand-operated crane.
Credit: NASA TV.

The International Space Station (ISS) has a new camera eye and a once-more complete oxygen generator system after an extra-long spacewalk by its two-astronaut crew.

ISS Expedition 13 commander Pavel Vinogradov and flight engineer Jeffrey Williams spent six hours and 31 minutes making repairs and collecting experiments along the space station's exterior. Their excursion lasted almost an hour longer than planned after the astronauts fell behind in their work schedule.

But the extra time, 31 minutes more than typical spacewalks in Russian-built Orlan spacesuits, allowed the astronauts to replace a faulty camera on the station's Mobile Base System railcar. The task was a late addition to the spacewalk lineup and was almost cancelled due to today's time crunch.

Vinogradov and Williams began their extended spacewalk at 6:48 p.m. EDT (2248 GMT), when they stepped outside the station's Russian-built Pirs docking compartment while flying 220 miles over Southern Asia.

"Here I am hanging by a tether by the Pacific Ocean," Vinogradov said during the spacewalk. "It's like a fairy tale."

The Expedition 13 crew made crucial repairs to several station systems, but at some loss.

During the spacewalk, Vinogradov watched a foot restraint adapter, which had previously linked him to the station's Strela crane, drift off into space.

"That's bad," Vinogradov said as the cylindrical adapter flew beyond the space station's solar arrays.

But NASA officials said the errant adapter is believed to have drifted out of the space station's orbital plane and will not pose a debris risk to the ISS at this time.

Major repairs

The Expedition 13 crew made two key ISS repairs during today's spacewalk.

Vinogradov replaced a clogged vent nozzle used to dump excess hydrogen overboard by the space station's Elektron oxygen generator - the primary oxygen producer aboard the orbital laboratory.

The Elektron device separates water into oxygen and hydrogen through electrolysis, but has had a finicky track record since an electrolyte leak contaminated its hydrogen vent last year. The leak rendered the vent unusable, and forced engineers to reroute the Elektron's hydrogen waste through an alternate route that led to routine downtime for the generator.

NASA spokesperson Rob Navias said that, with its hydrogen vent system once again functional, the Elektron oxygen generator will be reactivated on Monday.

Vinogradov and Williams also replaced a broken video camera that provides key views from the space station's railcar-like Mobile Base System, which is used to haul the outpost's robotic arm along its main truss segment.

The camera will provide a key backup to other views during STS-115, NASA's next shuttle flight to fly after the planned July launch of STS-121, when spacewalking astronauts will install new solar arrays outside the ISS, the space agency said.

Other tasks

In other tasks, Williams retrieved an exposure experiment and the last of three Russian Biorisk containers designed to study microorganisms that have been subjected to the weightlessness of space. Two other Biorisk canisters were recovered in previous spacewalks.

Vinogradov collected a metal plate dubbed Kromka, which ISS engineers will use to study the effect of thruster firings on the space station structure.

He also photographed a navigation antenna on the aft end of the station's Zvezda service module, which may be interfering with a nearby thruster, and repositioned a similar antenna to avoid signal disruption from an errant cable. The antennas will help a future European cargo ship make unmanned deliveries to the ISS.

The busy spacewalk is the first of two planned spacewalks for the Expedition 13 crew.

Williams is expected to don a U.S. spacesuit and work outside the ISS later this summer with European astronaut Thomas Reiter, who is slated to join the Expedition 13 crew when the space shuttle Discovery visits the station in July.

The spacewalk also marked the 65th spacewalk outside the ISS. It was the second career spacewalk for Williams and the sixth for Vinogradov, who still marveled at some of the excursion's simple tasks despite his experience.

"This is something I've never done before, I'm wiping my hands in space," Vinogradov said as he brushed his spacesuit clean after one task. "I always say wipe your hands."