Tucson News NowNASA scrubs Endeavour launch over heater issue

NASA scrubs Endeavour launch over heater issue

KENNEDY SPACE CENTER, FL (RNN) - NASA has scrubbed the scheduled launch of the Space Shuttle Endeavour due to a technical problem and has tentatively been rescheduled for Monday.

Friday's STS-134 launch has been delayed for a minimum of two days, according to NASA.

"Today, the orbiter is not ready to fly," said Shuttle Launch Director Mike Leinbach in a post-scrub appearance on NASA TV.

Leinbach blamed the scrub on an issue with a heater on auxiliary power unit (APU), which produces pressure for the orbiter's hydraulic system.

A thermostat on APU 1 failed and couldn't be brought back to life. There are two thermostats on each of the shuttle's three AUPs, which help monitor the operational heat for launch.

A spokeswoman at Kennedy Space Center in Florida confirmed to Raycom News Network that the launch was scrubbed but declined to elaborate on what caused the problem with the heaters.

Leinbach said the cause was likely a short in the shuttle's load control assembly box or in one of the electrical lines coming to or from it. A second heater may also be affected.

He said he did not feel comfortable committing to a launch that could have resulted in a frozen fuel line and potentially damaging effects on the shuttle's re-reentry into the earth's atmosphere.

Before they can attempt to fix the issue, all fuel has to be drained from the shuttle itself, in addition to its external fuel tanks, which is expected to finish sometime Saturday evening.

If the problem is indeed a thermostat, and not something more serious, the launch will be attempted on Monday, Leinbach said.

If it turns out to be a problem with a box in the lower control assembly, he said it would take longer because the retest takes at least 48 hours.

He also said that they have until Wednesday to launch Endeavour before they have to stand down for the launch of the Atlas-V 401 satellite.

Friday's 3:47 p.m. ET launch time would have been the final lift-off into space for Endeavour, which will be retired after its mission and housed at the Intrepid Sea, Air and Space Museum in Manhattan, NY.

The shuttle mission to the International Space Station has received extra media attention, because of its commander, Capt. Mark Kelly, who is the husband of Rep. Gabrielle Giffords, D-AZ. Giffords is one of 19 people who were shot at a "Congress on Your Corner" event in Tucson, AZ, on Jan. 8. Six died in the mass shooting.

Giffords arrived in Florida on Wednesday for her first trip away from a rehab stint at TIRR Hermann Memorial hospital in Houston.

Giffords' medical team on Monday deemed her "medically able" to attend the launch, viewing the trip as a key part of the congresswoman's therapy progression.

"Her attending the launch is a goal that we were working toward, and we have achieved that end," said Dr. Gerard Francisco, chief medical officer at TIRR, in a news release issued Monday. "She has made remarkable progress in her rehabilitation, and we saw no reason why she could not travel safely to Florida."

President Barack Obama and his family were scheduled to attend the launch with Giffords Friday.

NASA immediately began draining the shuttle's external fuel tank, which is loaded with 528,000 gallons of fuel. The process is lasted about an hour and was followed by an assessment meeting of the shuttle's launch team.

Leinbach said it was an unfortunate setback, but the crew was prepared.

"Disappointing day for team Endeavour and the astronauts but as we say in this business, we will not fly until we're ready."

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