![]() ![]() Despite two safety officials being contacted, safety personnel took no actions to obtain imagery.Īfter discussion with other MMT members, the Shuttle Program Manager cancelled the DoD imagery request. The AA for S&MA stated that he would defer to Shuttle management in handling such a request. The JSC manager for Shuttle Safety program said he was told this was an “in-family” event – meaning it was normal and nothing to worry about. Seven days into the mission, a NASA Headquarters Safety and Mission Assurance (S&MA) manager called a JSC S&MA manager for the Shuttle Safety Program and the Associate Administrator (AA) for S&MA, to discuss a potential DoD imaging request. The imaging request was viewed by Shuttle Program Managers as a non-critical engineering desire rather than a critical operational need. The DAT assigned the NASA Co-Chair to pursue a request for imagery of the vehicle on-orbit – constituting the third request for imagery – by going through the Engineering department rather than through Shuttle Program Managers. The assumptions and uncertainty incorporated in this analysis were never fully presented to the Mission Management Team (MMT). Because foam is less dense than ice, the DAT used a qualitative extrapolation of the test data and engineering judgment that a foam impact angle of up to 21° would not penetrate the RCC. Crater was classified as a “conservative” tool based on its projections of ice projectile damage to RCC turning out to be more severe than that achieved experimentally. Crater was suitable for small debris impacts, on the order of 49cm3 – versus 19,665cm3, the estimated size of the bipod ramp foam. Without additional on-orbit pictures, the DAT was restricted to using a mathematical modeling tool called Crater, that predicts the depth to which debris will penetrate a Thermal Protection System (TPS) tile. The first formal DAT meeting was held on January 21st, five days into the mission.Ī trajectory analysis that used a computational fluid dynamics approach to determine the likely position and velocity histories of the foam (Credits: NASA Ref p61). The Department of Defense (DoD) Manned Space Flight Support Office began implementing the request, albeit with the assurance from MCC that this was merely information gathering, not a formal request for action. DAT contractor engineers prompted a NASA Shuttle manager to make a second imagery request. The Program Manager agreed to explore the possibility – this was the first imagery request of the mission.Ī Debris Assessment Team (DAT) was formed with NASA and contractor engineers. On the second day of the mission, the Intercenter Photo Working Group Chair contacted the Shuttle Program Manager for Launch Integration at KSC to request imagery of Columbia’s left wing on-orbit. – In the video below, the apparently trouble-free launch of Columbia STS-107. Columbia continued its 16 day mission without further incident – until Entry Interface. MCC also emailed a short video clip of the foam strike. MCC stated there was “ absolutely no concern for entry” because the phenomenon had been seen before. On flight day eight, MCC emailed the crew that post-launch photo analysis showed External Tank foam had struck the orbiter’s left wing during ascent. Neither the crew nor MCC were aware that on flight day two an Air Force Command review of radar tracking data detected an object drifting away from the orbiter, that subsequent analysis suggested may have been related to the foam strike. The analysis revealed that the debris was approximately 53-68cm long and 30-45cm wide, tumbling and moving at a relative velocity of 670-922km/h at the time of impact. The impact was detected the next day during the detailed review of all launch camera photography that is conducted after every Shuttle launch. This incident was not seen by anyone on the ground or in the Kennedy Space Center (KSC) Firing Room or Johnson Space Center (JSC) Mission Control Center (MCC) there was no onboard indication to the crew. The foam impacted under the leading edge of the left wing at 81.9 seconds. At 81.7 seconds after launch, when the Shuttle was at about 20,000m and traveling at Mach 2.46 (2,655km/h), a large piece of insulating foam came off the External Tank (ET) left bipod ramp area, close to where the orbiter attaches to the ET. ![]() The Space Shuttle Columbia STS-107 was launched on Januat 10:39 a.m. This article presents a technical overview of the accident, its cause, and the post-flight consequences. The Space Shuttle Columbia disaster is one of the most tragic chapters of spaceflight history. ![]() A color enhanced, de-blurred still frame of the foam strike, derived from video recording (Credits: NASA). ![]()
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