Space Cryocooler Contamination Lessons Learned and Recommended Control Procedures

One of the most important characteristics of a space cryocooler is its reliability over a lifetime, typically in excess of 7 years. While design improvements have reduced the probability of mechanical failure, performance degradation directly traceable to internal contamination has been observed across the industry in significant numbers, both in endurance test units and flight units. Therefore, the risk posed by excessive contamination is still a major concern and should be addressed in a consistent standard throughout industry.