On-Demand Small Payload Return Solution from ISS: Low-Temperature Passive Thermal Control Design

The Small Payload Quick Return (SPQR) system would be the first vehicle to effectively parachute from space, permitting small payloads to be routinely delivered from the International Space Station (ISS). This innovative reentry system incorporates a passive thermal design simple enough to be low cost and light weight, making it one of the first feasible on-demand payload return capability solutions to be presented to the ISS program. The thermal analysis and control for the system can be broken down into 4 different regimes beginning with the drag-induced de-orbit system (Exo-brake) and ending with the recovery of the payload with a GPS-guided parafoil. The SPQR concept was created by researchers at NASA Ames Research Center, who are managing the incremental development flights. The first of these flights is scheduled for December 2011 with proposed follow-on tests to occur in 2012. The thermal control analysis for the SPQR vehicle was performed in part by Paragon Space Development Corporation, with the focus on the design and development of the Payload Containment and Thermal Control Unit (PCTCU). This system is capable of being maintained at 1 atm, and is shown to control internal payload temperature to less than 4° C throughout the described re-entry phases.