OPS 5112

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OPS 5112
Mission typeNavigation
OperatorUS Air Force
COSPAR ID1978-047A[1]
SATCAT no.10893[1]
Mission duration5 years (planned)
9 12 years (achieved)
Spacecraft properties
Spacecraft typeGPS Block I
Launch mass759 kilograms (1,673 lb)[2]
Start of mission
Launch date13 May 1978, 10:34 (1978-05-13UTC10:34Z) UTC
RocketAtlas E/F SGS-1, 49F[3]
Launch siteVandenberg SLC-3E[3]
End of mission
DeactivatedFebruary 1988 (1988-03)
Orbital parameters
Reference systemGeocentric
RegimeMedium Earth
Perigee altitude20,056 kilometres (12,462 mi)[4]
Apogee altitude20,195 kilometres (12,549 mi)[4]
Inclination63.1 degrees[4]
Period715.67 minutes[4]

OPS 5112, also known as Navstar 2, NDS-2, GPS I-2 and GPS SVN-2, was an American navigation satellite launched in 1978 as part of the Global Positioning System development programme. It was the second of eleven Block I GPS satellites to be launched.[2]

OPS 5112 was launched at 10:34 UTC on 13 May 1978, atop an Atlas E/F carrier rocket with an SGS-1 upper stage. The Atlas used had the serial number 49F, and was originally built as an Atlas F.[3] The launch took place from Space Launch Complex 3E at Vandenberg Air Force Base,[5] and placed OPS 5112 into a transfer orbit. The satellite raised itself into medium Earth orbit using a Star-27 apogee motor.[2]

By 20 June 1978, OPS 5112 was in an orbit with a perigee of 20,056 kilometres (12,462 mi), an apogee of 20,195 kilometres (12,549 mi), a period of 715.67 minutes, and 63.1 degrees of inclination to the equator.[4] The satellite had a design life of 5 years and a mass of 758 kilograms (1,671 lb).[2] It broadcast the PRN 07 signal in the GPS demonstration constellation, and was retired from service in early-mid February 1988.


  1. ^ a b "Navstar 2". US National Space Science Data Center. Retrieved 25 June 2012.
  2. ^ a b c d e Krebs, Gunter. "GPS (Navstar)". Gunter's Space Page. Retrieved 12 July 2012.
  3. ^ a b c McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 12 July 2012.
  4. ^ a b c d e McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 12 July 2012.
  5. ^ McDowell, Jonathan. "Launch List". Launch Vehicle Database. Jonathan's Space Page. Retrieved 12 July 2012.