CAPE CANAVERAL, Fla. - The launch of NASA's space shuttle Atlantis will take place no earlier than Saturday, Dec. 8, at 3:43 p.m. EST. Thursday's scheduled liftoff from NASA's Kennedy Space Center, Fla., was postponed because of a problem with a fuel cutoff sensor system inside the shuttle's external fuel tank.
The fuel cutoff sensor system is one of several that protect the shuttle's main engines by triggering their shut down if fuel runs unexpectedly low. Launch Commit Criteria require that three of the four sensor systems function properly before liftoff.
Space Shuttle Program managers will hold a Mission Management Team meeting Friday at 2 p.m. to discuss the issue and determine the steps necessary to start a new launch countdown. A news conference will be held at approximately 5 p.m. after the meeting's conclusion.
On Thursday morning, two of the four engine cutoff, or ECO, sensors inside the liquid hydrogen section of the tank failed a routine prelaunch check. Following the launch postponement, the tank's liquid oxygen and liquid hydrogen were drained. While the tank was being emptied, engineers monitored and collected data on the liquid hydrogen sensors that failed. During that process, another sensor gave a false reading, indicating that the tank was "wet," when it was dry. All ECO sensors are now indicating dry as they should be.
During Atlantis' 11-day mission to the International Space Station, the shuttle and station crews will work with ground teams to install and activate the European Space Agency's Columbus laboratory. The new lab will expand the station's scientific research capabilities.