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National Aeronautics and Space Administration

EVA23Water Intrusion

ECFT- – Crew incorrectly attributed water in EV2's helmet after EVA 22 to the drink bag. (Intermediate Cause 1) Supporting Evidence: After EVA 22 ended, the audio logs and interview transcripts revealed that EV2 had indicated that he saw some water escape past his bite valve during repress and that maybe this had happened because his chin was resting on the bite valve while he was in a tucked position. This conclusion was consistent with their understanding of how the drink bag operated. See ECFT-1.1 ECFT- – Crew was not trained to recognize this failure mode. (Intermediate Cause 7) Supporting Evidence: See ECFT-3.1.2

Airflow contamination Procedure did not address the failure mode. ECFT-3.1.4

Flight Rule to address this FM did not exist. ECFT-

MOD did not understand the failure mode. ECFT-

Figure 3-55 Causes under ECFT 3.1.4 ECFT-3.1.4 – Airflow contamination procedure did not address the failure mode. (Intermediate Cause 10) Supporting Evidence: The “Air Flow Contamination” procedure that has been in the EMU cuff checklist since prior to 1989 lists steps to take in the event of LiOH dust or LiOH contaminated water in the EMU helmet--open the helmet purge valve and terminate the EVA. One section of the procedure that would have applied in this case, “If excessive water in the helmet” leads to a step that just states “√ MCC” with no further instructions. This means contact Mission Control and await further guidance. No mention is


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...