In a meeting held today at Kennedy Space Center, STS-122 mission managers underwent what was called a passionate discussion regarding the malfunctioning sensors in the liquid hydrogen fuel tank of space shuttle Atlantis. The ultimate outcome of this meeting was the unanimous decision to go ahead with a launch of the shuttle on Sunday, Dec. 9, at 3:20 p.m.
The mission management team meeting, which included representatives of the European Space Agency as well as the shuttle’s flight crew, yielded a new criteria for the launch. This new plan will require the functionality of all four sensors as well as a launch window tightened to only one minute. At the first sign of a violation to any of these rules, the launch will be scrubbed and the managers will go ahead with tanking tests to further troubleshoot the issue.
“This is what we consider to be an unexplained anomaly,” said LeRoy Cain, chair, mission management team. “We don’t understand it’s root cause.”
The mission managers brought in outside engineering experts to consider other explanations and troubleshooting tactics. The team also advocated the addition of a new voltage measurement system to see if the sensor’s readings are legitimate or the result of an electrical malfunction resulting from open circuit. If the shuttle makes it’s launch tomorrow this will preserve the possibility of the mission’s fourth spacewalk.
During the original Dec. 6 launch day two of the four LH2 fuel sensors failed simulated tests. After the launch was scrubbed, further testing showed the trouble to occur again at random. If these failures were to occur during an actual flight, it could mean extreme damage to the shuttle’s engines.
“If everything works perfectly, as we expect form past history, we will fly,” said Wayne Hale, space shuttle program manager.