Responsive access to space: Space Test Program Mission S26

Space Test Program Mission S26 (STP-S26) is the twenty sixth dedicated small launch vehicle mission of the Department of Defense Space Test Program. STP-S26 extends previous standard interface development efforts, implementing a number of capabilities aimed at enabling responsive access to space for small experimental satellites and payloads. The STP-S26 Minotaur-IV launch vehicle is configured in a Multi-Payload Adaptor configuration which includes the following features: (1) The Multi-Payload Adaptor (MPA), which was developed by Orbital Sciences Corporation for STP to launch up to four ESPA-class satellites on the Minotaur-IV. (2) Provisions for the inclusion of up to four Poly-Picosat Orbital Deployers (P/PODs) to be mounted on the Stage 4 avionics cylinder. (3) A dual orbit capability provided by the Hydrazine Auxiliary Propulsion System (HAPS). The design provides volume and mass for four additional payloads attached to the HAPS avionics cylinder. The actual payload manifest of STP-S26 includes four ESPA-class satellites manifested on the MPA and three cubesats. One of the four ESPA-class satellites is STPSat-2, the first Standard Interface Vehicle. STP implemented a flexible, responsive ¿dual path¿ process for a late satellite manifest change. The goal was to delay the final manifest decision as late as possible while minimizing risk. STP-S26 is a complex multi-payload mission and incorporates many innovative capabilities enabling responsive access to space.