The launch of space shuttle Atlantis has been rescheduled for no earlier than Jan. 2, 2008. The postponement will give engineers time to evaluate false readings from the engine cutoff sensor system that measures liquid hydrogen in the external tank.

Of the four engine cutoff sensors, ECO sensor number three gave false readings during Sunday’s launch attempt. The sensor system is one of several that protect the shuttle’s main engines by triggering their shut down if fuel runs unexpectedly low.

Atlantis’ scheduled launch on Thursday was delayed after two of the four engine cutoff, or ECO, sensors in the shuttle’s external fuel tank gave false readings. A third sensor failed after the tank was drained of fuel.

… decision was made this afternoon. Launch time set for 3:21 p.m., EST. 

CAPE CANAVERAL, Fla. - NASA is targeting the launch of space shuttle Atlantis no earlier than Sunday, Dec. 9, at 3:21 p.m. EST from the Kennedy Space Center, Fla. Shuttle program managers made the decision after a meeting Friday to review data on a problem with a fuel cutoff sensor system inside the shuttle and its external fuel tank.

Because of the length of the meeting, the managers agreed that targeting Sunday would allow the launch and management teams appropriate time to rest and prepare. The Mission Management Team will meet Saturday at 1 p.m. to decide whether to make a Sunday attempt. A news conference will be held after the meeting’s conclusion.

Atlantis’ scheduled launch Thursday was delayed after two ECO sensors gave false readings. A third sensor failed after the tank was drained of fuel. The fuel cutoff sensor system is one of several that protects the shuttle’s main engines by triggering their shut down if fuel runs unexpectedly low.

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.

Sensor problems persist.

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.

At Thursday evening’s press conference, NASA mission managers announced that the launch of space shuttle Atlantis would be delayed for 48 hours.

Liftoff of mission STS-122 from NASA’s Kennedy Space Center is now scheduled for Saturday, Dec. 8 at 3:43 p.m. EST according to LeRoy Cain, Mission Management Team chairman.

Weather officer Captain Chris Lovett said the weather conditions are slightly less favorable for Saturday’s launch with a 40 percent chance of weather prohibiting launch.

Thursday’s launch was scrubbed when two of four LH2 Engine Cutoff (ECO) sensors failed to respond appropriately during tanking, which is a Launch Commit Violation.

Within the last 15 minutes, NASA has scrubbed today’s scheduled launch.

The launch team at NASA’s Kennedy Space Center is continuing its steady march toward a lift off Thursday afternoon for space shuttle Atlantis. The countdown is proceeding smoothly, NASA Test Director Jeff Spaulding said Wednesday.

Mission STS-122 is scheduled to launch at 4:31 p.m. EST from NASA’s Florida launch base. Atlantis will carry the European-developed Columbus laboratory and attach it to the International Space Station. Seven astronauts, including two from the European Space Agency, will fly aboard Atlantis.

The weather forecast calls for a 90 percent chance of acceptable conditions at launch time.