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National Aeronautics and Space Administration

EVA23Water Intrusion

Figure 3-17. LCVG Tubing and Connector A sixth possibility is water leakage from the water storage tankage, out through the pressurizing bladders, and into the Item 120 Dual Mode Relief Valve circuit, through an orifice and eventually into the suit at port T11 (Figure 3-3 and Figure 3-6). A seventh possible source is the water separator circuit, which consists of the spinning drum-and-pitot components (Figure 3-18– showing the path of water leaking into the ventilation loop via the fan inlet), the Item 134 check valve and filter (Figure 3-19), the Item 125 pump priming valve (Figure 3-20), the Item 141 gas trap (Figure 3-12) and the water flow passages linking the various elements of the circuit. The possible leak sources discussed above, as well as any others identified, were used by the ISS Investigation Team (IIT) and the Flight Safety Office of JSC’s Safety and Mission Assurance Directorate to construct a detailed fault tree (Appendix G). A systematic investigative program was then developed to eliminate non-contributors to the leakage failure and ultimately identify the proximate cause.


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...