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GPS-2 (Navstar-2)


GPS-2 (Global Positioning System) or Navstar-2 (Navigation System using Timing And ranging) are improved satellites of the second generation of the GPS navigation system.

The Block II satellites were the first full scale operational GPS satellites. They were designed to provide 14 days of operation without contact from the control segment.

Rockwell was the prime contractor, building a single Block 2 SVN 12 qualification vehicle under a 1981amendment to the Block I contract. In 1983 Rockwell was awarded a contract to build 28 Block II/IIA satellites.

The spacecraft was 3-axis stabilized, nadir pointing using reaction wheels. Two solar arrays supplied 710 Watts (EOL). S-Band (SGLS) communications were used for control and telemetry. A UHF channel provided cross-links between spacecraft. A hydrazine propulsion system was used for orbital correction. The payload included two L-Band navigation signals at 1575.42 MHz (L1) and 1227.60 MHz (L2). Each spacecraft carried 2 rubidium and 2 cesium clocks. Also carried as a secondary payload were nuclear detonation detection sensors (NDS).

Nation: USA
Type / Application: Navigation
Operator: US Air Force (USAF)
Contractors: Rockwell
Equipment: ?
Configuration: 3-Axis stabilized
Propulsion: Star-37XFP
Power: 2 deployable solar arrays, batteries
Lifetime: 7.5 years
Mass: 1660 kg
Orbit: 20200 km × 20200 km, 55.0
Satellite COSPAR Date LS Launch Vehicle Remarks
GPS-2 (Navstar 12) - not launched
GPS-2 1 (Navstar 14, USA 35) 1989-013A 14.02.1989 CC LC-17A Delta-6925
GPS-2 2 (Navstar 13, USA 38) 1989-044A 10.06.1989 CC LC-17A Delta-6925
GPS-2 3 (Navstar 16, USA 42) 1989-064A 18.08.1989 CC LC-17A Delta-6925
GPS-2 4 (Navstar 19, USA 47) 1989-085A 21.10.1989 CC LC-17A Delta-6925
GPS-2 5 (Navstar 17, USA 49) 1989-097A 11.12.1989 CC LC-17B Delta-6925
GPS-2 6 (Navstar 18, USA 50) 1990-008A 24.01.1990 CC LC-17A Delta-6925
GPS-2 7 (Navstar 20, USA 54) 1990-025A 26.03.1990 CC LC-17A Delta-6925
GPS-2 8 (Navstar 21, USA 63) 1990-068A 02.08.1990 CC LC-17A Delta-6925
GPS-2 9 (Navstar 15, USA 64) 1990-088A 01.10.1990 CC LC-17A Delta-6925