International Space Station (ISS) Carbon Dioxide Removal Assembly (CDRA) On-Orbit Performance

The Carbon Dioxide Removal Assembly (CDRA) is an essential part of the International Space Station (ISS) Environmental Control and Life Support (ECLS) system. The CDRA provides carbon dioxide (C02) removal from the ISS on-orbit modules. Currently, the CDRA is the secondary removal system on the ISS, with the primary system being the Russian Vozdukh, The CDRA encountered some operational problems since being launched to orbit on Flight 5A in February 2001. While on-orbit, several hardware modifications and maintenance activities have been necessary to restore the CDRA to nominal capability. This paper describes the troubleshooting activities and briefly explains the failures, the operational work-arounds, and the on-orbit hardware repairs performed to return the CDRA to operational status.