OV1-1

In the early 1960s, the US Air Force initiated an effort to reduce the expense of space research. Satellite production was standardized to improve reliability and cost-efficiency. The research satellites would fly on test vehicles or be piggybacked with other satellites. In 1961, the Air Force Office of Aerospace Research (OAR) created the Aerospace Research Support Program (ARSP) to request satellite research proposals and choose mission experiments. The USAF Space and Missiles Organization created their own analog of the ARSP called the Space Experiments Support Program (SESP), which sponsored a greater proportion of technological experiments than the ARSP.[2]^:417

The OV1 series was originally designed as adaptations of the 2.7 m "Scientific Passenger Pods" (SPP), which, starting on 2 October 1961, rode piggyback on suborbital Atlas missile tests and conducted scientific experiments during their short time in space. General Dynamics received a $2 million contract on 13 September 1963 to build a new version of the SPP (called the Atlas Retained Structure (ARS)) that would carry a self-orbiting satellite. Once the Atlas missile and ARS reached apogee, the satellite inside would be deployed and thrust itself into orbit. In addition to the orbital SPP, General Dynamics would create six of these satellites, each to be 3.66 m (12.0 ft) long with a diameter of .762 m (2 ft 6.0 in), able to carry a 136 kg (300 lb) payload into a circular 805 km (500 mi) orbit.

Dubbed "Satellite for Aerospace Research" (SATAR), the series of satellites were originally to be launched from the Eastern Test Range on Atlas missions testing experimental Advanced Ballistic Re-Entry System (ABRES) nosecones. However, in 1964, the Air Force transferred ABRES launches to the Western Test Range, causing a year's delay for the program. Moreover, because WTR launches would be into polar orbit as opposed to the low-inclination orbits typical of ETR launches, less mass could be lofted into orbit using the same thrust, and the mass of the SATAR satellites had to be reduced.[2]^:417

OV1-1 with solid motor undergoing balance test at General Dynamics/Astronautics in San Diego

OV1-1, like the others in the OV1 series, was 1.387 m (4 ft 6.6 in) long and .69 m (2 ft 3 in) in diameter, and consisted of a cylindrical experiment housing capped with flattened cones on both ends[3] containing 5000 solar cells (2500 on each end)[4] producing 22 watts of power. Two .46 m (1 ft 6 in) antennas for transmitting telemetry and receiving commands extended from the sides of the spacecraft. 12 helium-pressurized hydrogen peroxide thrusters provided attitude control.[2]^:418 Spacecraft systems, including telemetry, command systems, and data recording and playback were located in the satellite's end-caps. An onboard timer would shut down the satellite after 180 days of operation.[4]

OV1-1 weighed 100 lb (45 kg),[5] 189.2 lb (85.8 kg) with its Altair booster.[6]

170,000 cubic centimetres (6.0 cu ft) of space in the cylindrical portion of the spacecraft[4] was allocated to a seven experiment package designed to measure micrometeoroid density, cosmic radio noise, electron density variations, magnetic fields, proton concentrations, and Earth-based infrared and ultraviolet emissions.[2]^:419

Launched from Vandenberg's 576-B-3 launch pad at 21 January 1965 21:34:54 UTC,[1] OV1-1 (then called Aerospace Research Vehicle (ARV)) was the first satellite launched into a western-facing orbit.[5] Five minutes after launch, the ARS was designed to open so that the OV satellite could propel itself out at Atlas apogee.[4] While the Atlas D carrying OV1-1 flew without incident, OV1-1's Altair booster did not fire at apogee, and the spacecraft remained stranded in its ARS, returning no data.[2]^:419

The OV1 program ultimately comprised 22 missions, the last flying on 19 September 1971.[2]^:421