United States orbital transfer vehicle programs

Abstract

Five U.S. orbital transfer vehicles carrying spacecraft to higher energy orbits than achievable by the Space Shuttle or various expandable launch vehicles are studied. These vehicles are the Payload Assist Module-Delta (PAM-D), an upgraded version designated PAM-DII, the Inertial Upper Stage (IUS), the U.S. Transfer Orbit Stage (TOS), and the Orbital Maneuvering Vehicle (OMV). Capabilities range from providing spacecraft with only a preprogrammed perigee velocity additions to man-in-the-loop remote controlled spacecraft rendezvous, docking, retrieval, and return to a space base. The PAM-D, PAM-DII, and IUS are mature vehicles currently available for mission support. Characteristics, flight records, and costs are defined. The TOS is being commercially developed while the OMV is government developed. The TOS and OMV capabilities, constraints, and costs are reviewed.