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GPS Block 1

Spacecraft · USA

Original archive entry. The text, images and links below are kept as they were written.

GPS Block 1
GPS Block 1
Credit: USAF

American navigation satellite. GPS Block 1 prototype satellites formed the GPS Demonstration system and were followed by the Block 2 operational system.

The spacecraft was 3-axis stabilized, nadir pointing using reaction wheels. Dual solar arrays supplied over 400 watts (EOL) and charged NiCd batteries. 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)

Block I satellites cost $ 20 million each. In 1974 Rockwell was awarded a contract to build 8 satellites. A 1978 contract amendment added 4 additional satellites. This was subsequently modified in 1981 for the twelfth satellite to be produced as the first GPS Block 2 qualification model.

Electric System: 0.40 average kW.

Related

Country
USA
Projects
Navstar
Stages
Star 27
Bibliography
2, 278, 5, 6

Photo Gallery

  • USA 10
    USA 10
    Credit: Manufacturer Image
  • USA 128
    USA 128
    Credit: Manufacturer Image

Chronology

11 events

1978 February 22

23:44 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3E. LV Family: Atlas. Launch Vehicle: Atlas F/SVS.
  • Navstar 1 - . Payload: GPS SVN 1 / OPS 5111. Mass: 759 kg (1,673 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 10684 . COSPAR: 1978-020A. Apogee: 20,560 km (12,770 mi). Perigee: 20,249 km (12,582 mi). Inclination: 64.50 deg. Period: 727.00 min.

    An Atlas booster was launched from Vandenberg AFB carrying the first NAVSTAR Satellite. The launch was successful, and the satellite functioned normally once in orbit. It was declared operational on 31 March. Also known as Navigational Development Satellite 1. Technology prototype of Navstar satellite.

1978 May 13

10:34 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3E. LV Family: Atlas. Launch Vehicle: Atlas F/SVS.
  • Navstar 2 - . Payload: GPS SVN 2 / OPS 5112. Mass: 759 kg (1,673 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 10893 . COSPAR: 1978-047A. Apogee: 20,653 km (12,833 mi). Perigee: 19,523 km (12,131 mi). Inclination: 63.60 deg. Period: 714.20 min.

    An Atlas booster was launched from Vandenberg AFB with the second NAVSTAR satellite. Launch was successful and the satellite functioned normally once in orbit. It began operating at its final station on 27 June. Also known as Navigational Development Satellite 2. Technology prototype of Navstar satellite.

1978 October 7

00:28 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3E. LV Family: Atlas. Launch Vehicle: Atlas F/SVS.
  • Navstar 3 - . Payload: GPS SVN 3 / OPS 5113. Mass: 759 kg (1,673 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 11054 . COSPAR: 1978-093A. Apogee: 20,941 km (13,012 mi). Perigee: 20,706 km (12,866 mi). Inclination: 63.30 deg. Period: 744.20 min.

    The third NAVSTAR satellite was launched from Vandenberg AFB on board an Atlas booster. Both the booster and the satellite itself functioned normally, and the satellite began operating at its final station on 31 October. Technology prototype of Navstar satellite.

1978 December 11

03:59 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3E. LV Family: Atlas. Launch Vehicle: Atlas F/SVS.
  • Navstar 4 - . Payload: GPS SVN 4 / OPS 5114. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 11141 . COSPAR: 1978-112A. Apogee: 21,012 km (13,056 mi). Perigee: 20,750 km (12,890 mi). Inclination: 64.60 deg. Period: 746.50 min. The fourth NAVSTAR satellite was successfully launched from Vandenberg AFB on board an Atlas booster. The satellite was due to begin operating at its final station in early January 1979. Global Positioning System. First pre-opertional Navstar satellite..

1980 February 9

23:08 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3E. LV Family: Atlas. Launch Vehicle: Atlas F/SVS.
  • Navstar 5 - . Payload: GPS SVN 5 / OPS 5117. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 11690 . COSPAR: 1980-011A. Apogee: 20,560 km (12,770 mi). Perigee: 19,805 km (12,306 mi). Inclination: 64.90 deg. Period: 718.00 min. Global Positioning System..

1980 April 26

22:00 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3E. LV Family: Atlas. Launch Vehicle: Atlas F/SVS.
  • Navstar 6 - . Payload: GPS SVN 6 / OPS 5118. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 11783 . COSPAR: 1980-032A. Apogee: 20,471 km (12,720 mi). Perigee: 19,387 km (12,046 mi). Inclination: 62.80 deg. Period: 707.80 min. Global Positioning System..

1981 December 19

01:10 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3E. LV Family: Atlas. Launch Vehicle: Atlas E/SVS. FAILURE: Failure.. Failed Stage: 1.
  • Navstar 7 - . Payload: GPS SVN 7. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. Decay Date: 1981-12-18 . Global Positioning System..

1983 July 14

10:21 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3W. LV Family: Atlas. Launch Vehicle: Atlas E/SGS-2.
  • Navstar 8 - . Payload: GPS SVN 8 / OPS 9794. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 14189 . COSPAR: 1983-072A. Apogee: 21,229 km (13,191 mi). Perigee: 20,757 km (12,897 mi). Inclination: 64.20 deg. Period: 751.10 min. Global Positioning System..

1984 June 13

11:37 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3W. LV Family: Atlas. Launch Vehicle: Atlas E/SGS-2.
  • USA 1 - . Payload: GPS SVN 9. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 15039 . COSPAR: 1984-059A. Apogee: 21,194 km (13,169 mi). Perigee: 20,681 km (12,850 mi). Inclination: 64.20 deg. Period: 748.80 min. Global Positioning System..

1984 September 8

21:41 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3W. LV Family: Atlas. Launch Vehicle: Atlas E/SGS-2.
  • USA 5 - . Payload: GPS SVN 10. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 15271 . COSPAR: 1984-097A. Apogee: 21,203 km (13,174 mi). Perigee: 20,612 km (12,807 mi). Inclination: 61.90 deg. Period: 747.60 min. Global Positioning System..

1985 October 9

02:53 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3W. LV Family: Atlas. Launch Vehicle: Atlas E/SGS-2.
  • USA 10 - . Payload: GPS SVN 11. Mass: 770 kg (1,690 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 1. USAF Sat Cat: 16129 . COSPAR: 1985-093A. Apogee: 21,673 km (13,466 mi). Perigee: 20,765 km (12,902 mi). Inclination: 65.00 deg. Period: 760.40 min. Global Positioning System..