Spaceflight Now




NewsAlert



Sign up for our NewsAlert service and have the latest news in astronomy and space e-mailed direct to your desktop.

Enter your e-mail address:

Privacy note: your e-mail address will not be used for any other purpose.



Shuttle's fuel sensor problem remains elusive
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: July 16, 2005



 
Discovery remains on the pad. In the foreground is the liquid hydrogen storage tank. At right is the 290-foot-tall water tower that holds 300,000 gallons of water, part of the sound suppression system during a launch. Credit: NASA-KSC
 
Engineers working inside the shuttle Discovery's cramped engine compartment this weekend have not yet found any obvious signs of trouble that might explain what caused one of four fuel sensors to operate improperly during last Wednesday's aborted countdown.

NASA managers are holding open the possibility of launching Discovery late next week, but that assumes the problem is found in the next few days, that a quick fix is possible and that engineers can demonstrate the problem won't crop up again.

Initial inspections carried out late Friday and today show the wiring in Discovery's engine compartment that routes data from the external tank fuel sensors to an electronic "black box" in avionics bay No. 5 appears to be in good shape with no obvious defects. But additional tests are planned and troubleshooters remain hopeful they will eventually find the culprit.

The engine cutoff - ECO - sensors serve as a critical safeguard in the event of other problems that could cause a main engine to shut down early or run too long. All four must be operational for a countdown to proceed (ECO sensor background, graphics and a chronology of Discovery's sensor problems are available from CBS News and Spaceflight Now: http://www.spaceflightnow.com/shuttle/sts114/050716ecographic/.

Earlier today, NASA released a statement from Discovery commander Eileen Collins, who said the astronauts are "keeping in close touch with the troubleshooting plan."

"We have confidence that the best people are working it," she said. "While the launch delay is disappointing, we have strong confidence that the mission will launch safely and successfully."

Spaceflight Now Plus
Additional coverage for subscribers:
VIDEO: FRIDAY AFTERNOON NEWS BRIEFING DIAL-UP | BROADBAND
VIDEO: THURSDAY'S UPDATE NEWS CONFERENCE DIAL-UP | BROADBAND
AUDIO: LISTEN TO THE NEWS CONFERENCE MP3 FILE

VIDEO: POST-SCRUB NEWS CONFERENCE PLAY
VIDEO: WEDNESDAY'S LAUNCH IS SCRUBBED PLAY
VIDEO: ASTRONAUTS DEPART QUARTERS FOR LAUNCH PAD PLAY
VIDEO: CREW DONS LAUNCH SPACESUITS PART 1 | PART 2
VIDEO: ASTRONAUTS GATHER FOR PRE-LAUNCH SNACK PLAY
VIDEO: PAD'S ROTATING SERVICE STRUCTURE ROLLED BACK PLAY
MORE: SHUTTLE RETURN TO FLIGHT VIDEO LISTING
SUBSCRIBE NOW

MISSION INDEX