CAPE CANAVERAL, Fla. - Spacewalking repairmen set out to tighten a loose blanket on an International Space Station solar wing Thursday after NASA took steps to eliminate any shock hazard from two new outpost arrays.

With the high-voltage wings moved into a position that inhibits their ability to generate electricity, astronauts Joe Tanner and Carlos Noriega floated outside the outpost around 11:15 a.m. Eastern Standard Time (16:15 GMT) - or about 35 minutes ahead of schedule.

The space station's new solar arrays await the arrival of Endeavour's spacewalking astronauts on Thursday in this image from NASA TV.

The job at hand: Pulling taut a glimmering blue and gold solar blanket that was left a bit slack after one of the station's two powerful new arrays was unfurled in orbit Sunday.

The tricky task calls for the spacewalking duo to scale a $600 million electric power tower that the Endeavour astronauts mounted to the outpost that same day. But Tanner told flight directors at NASA's Mission Control Center that he and Noriega are up to the job.

"We're looking forward to fixing the solar array," the veteran spacewalker said early Thursday.

Working nine stories above Endeavour's cargo bay, the astronauts will try to tighten the blanket with a hooked tool similar to a large crochet needle during a planned six-hour spacewalk being broadcast live on SPACE.com.

The so-called linchpin extractor will be used to pull a pair of loose blanket cables back up onto reel-and-pulley assemblies housed in the lengthy storage box that held the arrays before they were deployed.

Designed to stretch the blanket taut, the cables jumped off the reel portion of the assembly when the array was rolled out of the storage box during a less-than-perfect deployment.

The giant array - as well as its twin - both are fully functional, generating enough electricity to enable a closed station module to be opened up and outpost construction to continue with the planned delivery of a U.S. science lab in mid January.

A tight blanket, however, is crucial to making sure the fragile solar wing would not be damaged by forces imparted upon it whenever U.S. shuttles and Russian spacecraft dock at the station.

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What's more, the loose cables must be taut so the arrays can be retracted prior to a planned repositioning of the station's new electric power tower in late 2002 or early 2003.

As part of a makeshift repair plan, the power tower's massive starboard array was swung into a position that will enable Tanner and Noreiga can reach the loose cables.

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Both of the huge wings, meanwhile, are flying edge-on to the station's velocity vector - or direction of travel - to inhibit their ability to generate electricity during the repair work.

Two electrical grounding rods also were turned on to protect the astronauts. Yet to be proven in space, the suitcase-like devices are designed to neutralize any electrostatic discharge that could build up on metal station structure, creating a potential shock hazard.

Recent NASA analyses have raised questions about whether the grounding rods in fact work as advertised.

The uncertainty prompted NASA to put in place strict safety ground rules that call both grounding rods to be up and operating during spacewalking work outside the station.

In addition, flight controllers are required to either shunt the arrays or maneuver them into a position that inhibits the generation of electricity.

Stretching 240 feet (73 meters) from tip to tip, the two solar wings are capable of generating 64 kilowatts of high-voltage power - or enough electricity to adequately supply 30 average American homes (minus air conditioning).

In a bid to determine whether the grounding rods work, Tanner and Noreiga also plan to mount a new measuring device atop the five-story power tower.

The so-called Floating Potential Probe is designed to gauge electrical potential surrounding the station. Data from the device will help engineers determine whether a shock hazard in fact exists outside the outpost.

The spacewalking excursion is the last of three planned for Endeavour's mission.

Coming up Friday: The Endeavour astronauts plan to float inside the station to meet up with its first full-time tenants - U.S. astronaut Bill Shepherd and his two Russian colleagues, Yuri Gidzenko and Sergei Krikalev.

The Endeavour astronauts will deliver Christmas presents, fresh fruit and a small load of supplies to the station crew during a hatch-opening "welcome ceremony" scheduled for 9:30 a.m. EST (14:30 GMT) that day.

The two crews will bid adieu Saturday as Endeavour pulls away from the station and heads off on a two-day trip back to Earth. The winged spaceplane and its five astronauts remain scheduled to land at Kennedy Space Center at 6:19 p.m. EST (23:19 GMT) Dec. 11.