Engineers have trouble with two fuel line heaters
CAPE CANAVERAL, Fla. – A last-minute technical issue forced NASA officials to delay the launch of space shuttle Endeavour at about noon on Friday, a move certain to disappoint President Barack Obama, U.S. Rep. Gabrielle Giffords and hundreds of thousands of spectators who flooded to the Space Coast.
The next launch opportunity will be 2:34 p.m. EDT on Monday.
The issue involves two of three heating units aboard Endeavour designed to keep fuel lines from freezing in space. While these fuel lines are not particularly critical for launch, they are vital in ensuring that the airplane-like machinery of Endeavour work on re-entry – such as landing gear and its rudder speed brake.
“You don’t want frozen fuel lines, obviously,” said NASA spokesman Allard Beutel.
A short circuit – either in a switch box controlling the heaters or one of the electrical lines in or out of the box – has emerged as a primary suspect, but NASA engineers are not 100 percent certain. Hints of a problem started appearing earlier Friday morning. It may take until this morning, however, until technicians are able to access the broken piece.
“We’re an absolute minimum three days for turnaround right now,” said Launch Director Mike Leinbach, who made the call to scrub the launch at about 12:15 p.m., 3 1/2 hours before launch time. “We fly no orbiter before its time and today she just wasn’t ready to go.”
A van carrying astronauts to the launch pad was turned around en route when Leinbach decided to scrub the launch.
Obama and his family arrived shortly after the mission was scrubbed and decided to go on with the Kennedy Space Center tour that had been arranged for them.
Meanwhile, mission management team chairman Mike Moses and the engineering team were meeting to make a clearer assessment of what can be done and how long it would take.
Leinbach said the first heater was found to not be working and engineers tried a variety of tests to try to get it working again, but failed.
“Our troubleshooting proved it was a hard failure. We were not able to get it to come to life,” he said. “There was another heater upstream that was also exhibiting some erratic behavior.”
While an orbiter still can land with one broken unit, launch requirements force NASA to fly with all three working.