High efficiency cryocooler

The High Efficiency Cryocooler (HEC) is a highly reliable, >10 year life, space cryocooler. Design goals included very high capacity with low mass. The HEC achieved its 10 W at 95 K load while rejecting to 300 K with considerable margin and a flight configured mass of 4 Kg. This flight cooler design is being fabricated for a number of payloads. This paper describes the cooler, its measured performance, and its flight qualification.