Space photovoltaic reliability — Reasons why for solar power standards AIAA S-111-2005 AIAA S-112-2005 and AIAA S-122-2007

In order to mitigate on-orbit solar array issues due to the "best commercial practice" environment fostered by Act Reform in 1994, and based on lessons learned through on-orbit and ground test experience, Aerospace Corporation Technical Operating Reports TOR-2004(8583)-3554 [3] and TOR-2004(8583)-3557 were created by the author in 2004 to support acquisition of solar arrays for National Security Space satellites. To comply with federal law, community standards AIAA S-111-2005 and S-112-2005 were created for DoD procurements based on these TORs. When approved, the AIAA Committee on Standards (CoS) for Solar Cells and Solar Panels acknowledged that the reasons for each test should be made known to the users of the document. The documents are now the basis for the majority of government and commercial space solar array procurements worldwide. In 2007 the Air Force was directed to ensure that for new missions, all new technologies must be certified to (at least) technology readiness level 6 by key decision point "B" in the spacecraft acquisition process. In response to this, AIAA S-122-2007 implemented common TRL language to enable investment in research, development, productization, qualification, and implementation of new technologies. AIAA S-122-2007 also provides risk mitigation approaches that govern power margin for low-TRL power system approaches. From the new definitions, TRL status tables for solar cell technology are distributed annually to provide planners with state of practice and predictions of TRL readiness for forward mission planning. In this paper the original author and former chairman of the AIAA Committee on Solar Cells and Solar Panels supplies the previously unpublished rationale and reasons for requirements found in AIAA S-111-2005, AIAA S-112-2005, and AIAA S-122-2007.