Orbiting Vehicle or OV, originally designated SATAR, was a series of American satellites operated by the US Air Force, launched between 1965 and 1971. Forty seven satellites were built, of which forty three were launched and thirty seven reached orbit. With the exception of the OV3 series, and OV4-3, they were launched as secondary payloads, using excess space on other missions.
Five separate series of OV satellites were launched. The first satellites were OV1, which were carried on suborbital Atlas missile tests, and subsequently placed themselves into orbit by means of an Altair-2 kick motor. OV2 satellites were built using parts left over following the cancellation of the Advanced Research Environmental Test Satellite. Three OV2 spacecraft flew on Titan IIIC test flights. The OV3 satellites were the only ones in the series to be launched on dedicated rockets. Six were launched on Scout-B rockets between 1966 and 1967. OV4 satellites were launched as part of a test flight for the Manned Orbital Laboratory, with two satellites conducting a communications experiment whilst a third, OV4-3, was the primary payload, a Boilerplate mockup of the MOL space station. Two further OV4 satellites, duplicates of the first two, were built but not launched. OV5 satellites were launched as part of the ERS project, as secondary payloads on Titan IIIC rockets.
Typically, OV satellites carried scientific or technological experiments.