Lessons Learned Operating and Maintaining the Extravehicular Mobility Unit (EMU)

The Extra-vehicular Mobility Unit (EMU) is currently in its 24^th year of service; with plans to support Extra-vehicular Activity (EVA) needs through the year 2020 if so required. The tremendously successful history of this space suit is a credit to the original designers and manufacturers who built an extremely robust system. The design, largely unchanged since it's inception in the early 80's, has stood the test of time in supporting multiple missions and operating out of multiple vehicles. Currently the EMU is being used in an unprecedented number of EVAs to assemble and maintain the International Space Station. The EMU has provided NASA a wealth of information with regards to designing, sustaining, maintaining, and operating a low earth orbit (LEO) space suit. Over the years the EVA program has faced numerous design challenges and requirement changes associated with operation of the EMU which have resulted in several improvements and a few known issues. The background behind the issues, the rationale for the improvements and the overall compendium of lessons learned via operation of this miniature human space craft should be documented and used as one of the building blocks for the next generation suit (LEO and/or planetary). This paper provides a summary of the significant lessons learned that should be considered in the development of the next generation suit.