Houston Community News >> NASA Set to launch Atlantis

9/9/2006 Houston — NASA makes its fifth attempt to get Atlantis off the launch pad at 11:15 a.m. EDT on Saturday. If the mission is scrubbed again, the space agency must abandon for a few weeks its efforts to send the shuttle off on a construction mission at the international space station.

NASA stopped Friday's launch try only 45 minutes before its scheduled launch. This time it was a faulty fuel tank sensor _ the same glitch that thwarted two previous missions. The launch delay cost NASA $616,000. The shuttle's external fuel tanks were filled as scheduled in about 3 hours Saturday morning, exhibiting no problems with any sensor. Weather continued to look favorable, with only a 20 percent chance of storms interfering.

"Hi Mom," astronaut Heidemarie Stefanyshyn-Piper said, waving to a television camera as she and her five crew mates finished dressing in their orange flightsuits. They were then driven to the launch pad in a specially equipped van. They strapped into the shuttle and the hatch was sealed. From the space station 220 miles above Earth, astronaut Jeff Williams inquired how launch preparations were going

"Hopefully, we'll have some visitors heading on their way to you before long," Mission Control in Houston told him. Atlantis, which was supposed to launch on its 11-day mission on Aug. 27, has been kept earthbound by a lightning strike to the launch pad, Tropical Storm Ernesto, a glitch with a 30-year-old motor in an electricity-generating fuel cell, and finally the fuel tank sensor error. Originally the mission was scheduled for May 2003 but was first postponed by the 2003 Columbia accident.

Saturday is the last time NASA has to launch Atlantis before it has to go to the back of the line, behind a Russian Soyuz capsule that is slated for liftoff Sept. 18 on a flight to the space station. Both Atlantis and the Soyuz cannot be at the space station at the same time. If Atlantis cannot lift off on Saturday, it will have to wait at least until late September and even then, NASA will have to waive a post-Sept. 11 rule that says launches must be conducted in daylight so that the spaceship can be photographed for signs of damage

Friday's launch was scrubbed because a sensor in the hydrogen fuel tank gave an abnormal reading during a test as the shuttle was being fueled. Atlantis had been fueled with more than 500,000 gallons of supercold liquid hydrogen and oxygen, the six astronauts had donned their orange flightsuits and strapped themselves in, and the hatch to the shuttle had been closed, when NASA decided to postpone the launch with just 45 minutes to go until liftoff. After problems in previous flights with the sensor, NASA created a new rule requiring a stand-down of 24 hours when one of the hydrogen tank's four engine cutoff sensors doesn't work properly; such a delay would allow engineers to gather more data on the problem.

Atlantis' crew members will make three spacewalks during the 11-day mission to install the $372 million addition.

(Contributed by NC Times)