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National Aeronautics and Space Administration

EVA23Water Intrusion

Before a down-select and task definitions could occur, the EMU program was overtaken by events. The coolant loop pump package problem experienced by ISS during mid-December, 2013, emphasized the urgency of not only finding the root causes of the suit water intrusion incident, but also to determine means of achieving safe conduct of EVA before root cause identification and corrective action implementation. The coolant loop is one of several ISS systems which depend on EVA availability for risk mitigation. The replacement of the FPS and other components of SEMU 3011, and the ALCLR ion exchange bed analyses described above, along with the operational histories of SEMUs 3005 and 3010 were evaluated by a special team of JSC and UTAS experts, and their conclusions were that all three SEMUs were acceptable for at least three EVAs – the projected number required to change out a defective pump module package in the ISS coolant loop. SEMU 3011 was estimated to have slightly more margin than SEMU 3005, but either would be acceptable to be used in concert with SEMU 3010. The ISS Investigation Team will continue the hardware failure investigation to determine root causes and will identify corrective actions, along with a plan and schedule for implementation. The MIB Appointing Official will determine the requirements for closure of this investigation and will determine the continuing involvement of the Mishap Investigation Board.

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ISS EVA Suit Water Intrusion Mishap Investigation Report  

Report of the NASA Mishap Investigation Board examining the high visibility close call event of July 16, 2013 when ESA astronaut Luca Parmit...