NASA Assesses Trouble With ISS 'Wings'

S P A C E   C E N T E R, Houston, Dec. 4, 2001 -- NASA officials were assessing theiroptions early today about when to finish unfurling theinternational space station’s newly attached set of powerful solarpanels.

The debut of the $600 million solar wings was incomplete as onlythe right panel was deployed Sunday. Although the right wing hasstarted generating electricity, some of its tension cables appearedto be slack.

Engineers are trying to figure out if this will be a problem inunfurling the left wing and if that can be done today or should bedelayed until Tuesday, when astronauts on the space shuttleEndeavour conduct their second of three spacewalks during thismission.

No Big Hurry

“Since we are in a good, safe posture, there’s no reason to bein a big hurry and deploy the other blanket until we absolutelyunderstand what we saw, or what we’re looking at right now,” leadflight director Bill Reeves said.

The crew of Endeavour was to have a light schedule of activitiesMonday after a busy day of construction work.

During a 7½-hour spacewalk, astronauts Carlos Noriega and JoeTanner helped attach the truss containing the solar wings to the spacestation. It went smoothly until the right wing’s unfurlingdidn’t proceed after commander Brent Jett Jr. entered computercommands to do so.

A computer software problem prevented the latches and retentionpins on the wings to open so the panels could be deployed.

New software was sent up, and Jett was able to open all thelatches and pins, except one on the left wing. He continued to sendcommands and eventually freed the stuck pin.

The right wing’s deployment delighted Noriega and Tanner.

“Ah, it looks beautiful,” Noriega exclaimed.

“More power to the station,” Tanner said.

It took less than 14 minutes for the first folded wing to spreadto its full 115 feet.

Noriega and Tanner were the first spacewalkers to have theirhelmets equipped with small cameras that provided live views ofwhat they saw as they drove in bolts and released latches whileattaching the solar wings.

“We promise to make all of our movements nice and slow andsteady so nobody gets sick looking at the pictures,” Tanner saidbefore the flight.

Station Complete in 2006

The future of space station construction hinges on theastronauts’ ability to install the solar panels, which will providemuch-needed power to the newly inhabited outpost.

Two more spacewalks are planned this week by Tanner and Noriega,on Tuesday and Thursday, to finish wiring the solar wings and toinstall other equipment on the space station.

The solar wings, which will measure 240 feet from tip to tiponce completely unfurled, have a wingspan longer than that of aBoeing 777 jetliner. The solar panels, which are 38 feet across,will make the space station one of the brightest objects in thenight sky.

NASA expects the solar panels to generate 65 kilowatts at peakpower — four times what currently is produced by the smallRussian-built solar wings already on the space station. Withoutthis extra electricity, the space agency could not launch itsDestiny science lab in January — or any other power-hungry pieces.

By the time the space station is completed in 2006, NASA willhave installed three more sets of these solar wings. Each isdesigned to last 15 years and will keep operating even ifindividual solar cells are pierced by bits of space junk.

Space station commander Bill Shepherd and his two Russian crewmates havebeen on board since Nov. 2.

The two crews are unable to meet until Friday. The hatchesbetween the two craft remained sealed because of the difference incabin air pressure.