The design, fabrication and testing of a prototype spacecraft helium dewar

The objective of the Prototype Spacecraft Helium Dewar (PSHD) was to demonstrate a conversion of supercritical liquid helium (LHe) to superfluid LHe during a sounding rocket launch of 15 minute duration, by using the vacuum of space as a pump. The design was completed and the flight unit fabricated. Structural qualification tests were conducted on fiberglass/aluminum epoxy joints. Component tests of the Joule Thomson Expander and the counterflow heat exchanger were started, but terminated because of inconsistent results. The design and analysis of the Superfluid liquid helium conversion tank with its associated heat exchanger was completed. (jhd).