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National Aeronautics and Space Administration

O-14

EVA23Water Intrusion

There is no backup EVA capability in the event the need for a contingency EVA arises.

Supporting Evidence: The event on EVA 23 created a crisis within the ISS Program as it meant that there was no US contingency EVA capability in the event that a critical EVA had to be performed to ensure the safety of the crew or vehicle. Flight Rule B1-3 C. dictates that when a function normally provided by one partner’s segment is unavailable, the function shall be performed by another partner’s segment when possible. Given the inherently uncertain environmental and usage conditions faced by this legacy system and the risks of relying upon it solely and indefinitely, one or more dissimilar backup options should exist as with other essential vehicle systems. In the past such a capability existed. Russian EVA training suits (known as Orlan) were available and used in the JSC NBL and cross training of basic US task skills was performed by crew in Orlan suits. The Joint Airlock was designed with the intent that either suit could be used in that airlock. The Joint Airlock is in service on the ISS today, however, its use by Orlans has never been validated. Recommendation R-26: For critical external tasks, the ISS Program should provide at least one viable and proven dissimilar backup EVA capability (known candidates include dexterous robotics or Russian EVA) O-15 Lessons learned databases and corporate knowledge information exist, but are not always easily accessible, often incomplete and are not being fully utilized. Supporting Evidence: From interviews and review of existing EVA historical databases, the MIB learned that the loss of suit expertise that started in the early to mid-1990s continues and is uniform across multiple EVA organizations. Some of the loss is traceable to routine personnel retirements, but other losses were driven by decisions that declared the suit design to be sufficiently mature for ISS purposes. Upgrades and improvements have been relatively few compared to the efforts of the 1980s and early 90s. The depth and breadth of the work force has diminished as development and significant improvements gave way to sustaining engineering for obsolescence and failure support. Space Shuttle retirement, ISS completion and cancellation of the Constellation program further eroded EVA support since a number of key personnel were sustained by directly or indirectly supporting multiple programs. Just within MOD’s EVA ranks, civil servant and contractor head counts dropped from 54 to 38 after the completion of the Shuttle program and ISS assembly. Those remaining are stretched thin to cover routine training and multiple mission control shifts with little margin for contingency affairs without burnout. Such attrition over the years has depleted those that remember or have direct experience with this suit’s legacy, its hard earned lessons, inherent limitations or subtle messages suggesting renewed attention. These adverse labor conditions are not unique to EVA and exist across other areas of human spaceflight. Attempts to counteract this loss of expertise via knowledge capture and lessons learned exist, but are limited by lack of resources and time. It is admirable that EVA mission control skills are bolstered by innovative tactics such as staff mentoring and participation in non-EVA handovers (for currency with the latest flight control processes and personnel) and on-the-job training (OJT) roles during this era’s more limited spacewalks. Unfortunately, departure of contractor and civil servant experts occurs faster than information is collected and passed on. Those that remain have less time to explore history in meaningful ways because their labor is almost fully dedicated with preparation for present and future EVAs. Compared to the Shuttle and ISS assembly eras, hands-on hardware experience opportunities are much reduced with fewer crewmembers flying, fewer ground training/test events and even fewer on-orbit sorties. There is a trend toward very few vacuum chamber runs (8 ft., 11 ft., ETA, SSATA), no thermal

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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...

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