STP-SIV: Lessons learned through the first two Standard Interface Vehicles

Spacecraft standards can enable dramatic reduction in the cost, schedule, and risk of spaceflight. The Space Development & Test Directorate (SD) of the USAF Space and Missile Systems Center (SMC) developed standards for the Space Test Program-Standard Interface Vehicle (STP-SIV) program with prime contractor Ball Aerospace & Technologies Corp. STP-SIV is designed to provide affordable, repeatable, and reliable space access to the science and technology (S&T) community. STP-SIV provides the space community well-defined standard spacecraft (SC) to-payload (PL) interface on which to base PL designs for rapid mission formation. Rather than designing unique SC for each payload; the standards provide adaptable interfaces to accommodate a range of payloads. With the first STP-SIV spacecraft, STPSat-2, operating inorbit since November 2010 and the second vehicle, STPSat-3, bus integration completed in January 2011, two data sets are available to quantitatively examine: (1) Bus integration efficiency with commercially available components (2) Payload integration and test timelines achieved with standardization (3) Improvements in efficiency from vehicle #1 to #2 (4) Relative cost savings from vehicle #1 to #2 (4) Lessons learned, successes, and drawbacks of the standardization approach These topics will be explored using examples and data from both vehicle projects, offering the reader insight into the challenges and successes surrounding the topic. The paper will also describe how the lessons learned have contributed to program efficiencies for the second vehicle, recommendations for future improvements, and how the STP-SIV approach could be further evolved to meet the aggressive demands of rapid, low-cost, responsive space.