OPS 5113

OPS 5113, also known as Navstar 3, GPS I-3 and GPS SVN-3, was an American navigation satellite launched in 1978 as part of the Global Positioning System development programme. It was the third of eleven Block I GPS satellites to be launched.

Launch
OPS 5113 was launched at 00:28 UTC on 7 October 1978, atop an Atlas E/F carrier rocket with an SGS-1 upper stage. The Atlas used had the serial number 47F, and was originally built as an Atlas F. The launch took place from Space Launch Complex 3E at Vandenberg Air Force Base, and placed OPS 5113 into a transfer orbit. The satellite raised itself into medium Earth orbit using a Star-27 apogee motor.

Orbit
By 8 November 1978, OPS 5113 was in an orbit with a perigee of 20181 km, an apogee of 20186 km, a period of 718.02 minutes, and 62.8 degrees of inclination to the equator. The satellite had a design life of 5 years and a mass of 758 kg. It broadcast the PRN 06 signal in the GPS demonstration constellation, and was retired from service on 18 May 1992.