CAPE CANAVERAL, Florida Repairing an electrical connection in a U.S. space shuttle's fuel tank will push the already delayed launch of Europe's first permanent space laboratory beyond the current target date of January 10, NASA said on Thursday.
Two attempts this month to launch the shuttle Atlantis carrying the European lab to the International Space Station were canceled due to malfunctioning fuel sensors that are part of an emergency engine cutoff system.
NASA had rescheduled the flight for no earlier than January 10, but the repair plan under consideration will bump the launch by a few days to a few weeks, shuttle program manager Wayne Hale told reporters in a conference call.
"We need to get the problem resolved. Then we'll look at schedules," Hale said.
Engineers believe the problem resides in a two-sided, plug-like connector that relays electrical signals from the sensors in the fuel tank through wiring leading to the shuttle's engine compartment. The suspect part of the connector is scheduled to be removed on Saturday and taken for analysis at the Marshall Space Flight Center in Huntsville, Alabama.
SIMILAR PROBLEM FIXED
NASA hopes to pinpoint the problem by disassembling and testing the connector, but even if the faulty component cannot be traced, engineers have proposed to solder pins in place, bypassing the plug-like design.
A similar problem with fuel sensors in the Atlas-Centaur rockets, used for several decades to launch deep space exploration spacecraft and satellites, was fixed by this method, Hale said.
NASA may decide to test the repaired connector by filling the shuttle's fuel tank with supercold propellants in a practice run before getting ready to launch Europe's long-awaited Columbus module.
The sensor system is designed to cut off the shuttle's hydrogen-burning main engines if a leak or other problem causes the fuel to run out before the shuttle reaches its intended orbit. The fuel sensor system is a backup to the shuttle's flight computers which normally handle engine cutoffs.
Running the engines without fuel could trigger a catastrophic explosion.
Though NASA is on deadline to complete 12 construction and resupply flights to the space station by September 30, 2010, when the shuttle fleet is to be retired, Hale has repeatedly said the program will not compromise safety.
"I have a high degree of confidence that we'll be able to complete the space station by the time we have been mandated to retire the shuttle by," Hale said.