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GPS Block 2 and 2A

Spacecraft · USA

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

GPS IIA in assembly
GPS IIA in assembly
Credit: Hughes

American navigation satellite. The Navstar GPS constellation worked in concert with ground receivers to give precise location information to military and civilian users anywhere in the world.

Use of GPS receivers revolutionized civilian and military operations of every kind by providing precise location information. GPS Block 2 was the Operational system, following the Demonstration system comprised of Block 1 spacecraft. The Block 2A were "Advanced" versions of this spacecraft (mass 1816 kg). The complete basic constellation had 24 spacecraft in 6 high-altitude orbit planes. (4 slots per plane). In addition, on-orbit spares were placed in some planes in a fifth slot.

The spacecraft was 3-axis stabilized, nadir pointing using reaction wheels. Dual 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 were nuclear detonation detection sensors.

Launches were originally scheduled for Proton, Atlas, and Delta. Satellite costs $ 50 million for Block 2 and $ 40 million for Block 2A. Rockwell was the prime contractor, building a single Block 2 SVN 12 qualification vehicle under a 1981amendment to the Block I contract. This was followed in 1983 with a contract for 28 Block 2 and 2A satellites.

Electric System: 0.71 average kW.

Related

Country
USA
Projects
Navstar
Stages
Star 27
Bibliography
2, 4, 6, 12512, 12513

Photo Gallery

  • GPS Block 2R
    GPS Block 2R
    Credit: USAF
  • USA 128
    USA 128
    Credit: Manufacturer Image

Chronology

28 events

1989 February 14

18:30 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 35 - . Payload: GPS 2-1 / GPS SVN 14. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 19802 . COSPAR: 1989-013A. Apogee: 21,758 km (13,519 mi). Perigee: 21,480 km (13,340 mi). Inclination: 56.60 deg. Period: 777.00 min. First launch of second generation / operational Global Positioning System. Placed in Plane E Slot 1 of the constellation. Suffered a shutdown of its onboard reaction wheels on March 26, 2000. Decommissioned on April 14, 2000 and replaced by GPS 2R-4..

1989 June 10

22:19 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 38 - . Payload: GPS 2-2 / GPS SVN 13. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20061 . COSPAR: 1989-044A. Apogee: 20,514 km (12,746 mi). Perigee: 19,849 km (12,333 mi). Inclination: 54.80 deg. Period: 718.00 min. Global Positioning System. Placed in Plane B Slot 3..

1989 August 18

05:58 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 42 - . Payload: GPS 2-3 / GPS SVN 16. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20185 . COSPAR: 1989-064A. Apogee: 21,576 km (13,406 mi). Perigee: 21,509 km (13,365 mi). Inclination: 56.40 deg. Period: 773.80 min. Global Positioning System. Retired..

1989 October 21

09:31 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 47 - . Payload: GPS 2-4 / GPS SVN 19. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20302 . COSPAR: 1989-085A. Apogee: 21,236 km (13,195 mi). Perigee: 21,190 km (13,160 mi). Inclination: 53.30 deg. Period: 760.20 min. Global Positioning System. Placed in Plane A Slot 5..

1989 December 11

18:10 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 49 - . Payload: GPS 2-5 / GPS SVN 17. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20361 . COSPAR: 1989-097A. Apogee: 20,371 km (12,657 mi). Perigee: 19,992 km (12,422 mi). Inclination: 55.40 deg. Period: 718.00 min. Global Positioning System. Placed in Plane D Slot 3..

1990 January 24

22:55 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 50 - . Payload: GPS 2-6 / GPS SVN 18. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20452 . COSPAR: 1990-008A. Apogee: 21,226 km (13,189 mi). Perigee: 21,168 km (13,153 mi). Inclination: 55.00 deg. Period: 759.50 min. Global Positioning System. Retired..

1990 March 26

02:45 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 54 - . Payload: GPS 2-7 / GPS SVN 20. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20533 . COSPAR: 1990-025A. Apogee: 21,156 km (13,145 mi). Perigee: 20,960 km (13,020 mi). Inclination: 53.70 deg. Period: 753.80 min. Global Positioning System. Declared unusable on 21 May 1996 at 22:42 following two uncommanded changes in frequency standards..

1990 August 2

05:39 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 63 - . Payload: GPS 2-8 / GPS SVN 21. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20724 . COSPAR: 1990-068A. Apogee: 20,468 km (12,718 mi). Perigee: 19,896 km (12,362 mi). Inclination: 54.70 deg. Period: 718.00 min. Global Positioning System. Placed in Plane E Slot 2..

1990 October 1

21:56 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 6925.
  • USA 64 - . Payload: GPS 2-9 / GPS SVN 15. Mass: 1,665 kg (3,670 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20830 . COSPAR: 1990-088A. Apogee: 20,363 km (12,652 mi). Perigee: 20,002 km (12,428 mi). Inclination: 55.40 deg. Period: 718.00 min. Global Positioning System. Placed in Plane D Slot 5..

1990 November 26

21:39 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 66 - . Payload: GPS 2A-10 / GPS SVN 23. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 20959 . COSPAR: 1990-103A. Apogee: 20,384 km (12,666 mi). Perigee: 19,978 km (12,413 mi). Inclination: 54.90 deg. Period: 717.90 min. Global Positioning System. Placed in Plane E Slot 5..

1991 July 4

02:32 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 71 - . Payload: GPS 2A-11 / GPS SVN 24. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 21552 . COSPAR: 1991-047A. Apogee: 20,319 km (12,625 mi). Perigee: 20,043 km (12,454 mi). Inclination: 55.60 deg. Period: 717.90 min. Global Positioning System. Placed in Plane D Slot 1..

1992 February 23

22:29 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 79 - . Payload: GPS 2A-12 / GPS SVN 25. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 21890 . COSPAR: 1992-009A. Apogee: 20,332 km (12,633 mi). Perigee: 20,032 km (12,447 mi). Inclination: 54.20 deg. Period: 718.00 min. Global Positioning System. Placed in Plane A Slot 2..

1992 April 10

03:20 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 80 - . Payload: GPS 2A-13 / GPS SVN 28. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 21930 . COSPAR: 1992-019A. Apogee: 20,277 km (12,599 mi). Perigee: 20,082 km (12,478 mi). Inclination: 54.50 deg. Period: 717.90 min. Global Positioning System. Retired 15 August 1997..

1992 July 7

09:20 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 83 - . Payload: GPS 2A-14 / GPS SVN 26. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22014 . COSPAR: 1992-039A. Apogee: 20,400 km (12,600 mi). Perigee: 19,962 km (12,403 mi). Inclination: 54.90 deg. Period: 718.00 min. Global Positioning System. Placed in Plane F Slot 2..

1992 September 9

08:57 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 84 - . Payload: GPS 2A-15 / GPS SVN 27. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22108 . COSPAR: 1992-058A. Apogee: 20,453 km (12,708 mi). Perigee: 19,909 km (12,370 mi). Inclination: 54.50 deg. Period: 718.00 min. Global Positioning System. Placed in Plane A Slot 4..

1992 November 22

23:54 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 85 - . Payload: GPS 2A-16 / GPS SVN 32. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22231 . COSPAR: 1992-079A. Apogee: 20,325 km (12,629 mi). Perigee: 20,038 km (12,451 mi). Inclination: 55.50 deg. Period: 718.00 min. Global Positioning System. Placed in Plane F Slot 4..

1992 December 18

22:16 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 87 - . Payload: GPS 2A-17 / GPS SVN 29. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22275 . COSPAR: 1992-089A. Apogee: 20,324 km (12,628 mi). Perigee: 20,038 km (12,451 mi). Inclination: 54.70 deg. Period: 718.00 min. Global Positioning System. Placed in Plane F Slot 5..

1993 February 3

02:55 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 88 - . Payload: GPS 2A-18 / GPS SVN 22. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22446 . COSPAR: 1993-007A. Apogee: 20,359 km (12,650 mi). Perigee: 20,006 km (12,431 mi). Inclination: 54.80 deg. Period: 718.00 min. Global Positioning System. Placed in Plane Plane B Slot 1..

1993 March 30

03:09 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 90 - . Payload: GPS 2A-19 / GPS SVN 31. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22581 . COSPAR: 1993-017A. Apogee: 20,293 km (12,609 mi). Perigee: 20,072 km (12,472 mi). Inclination: 55.00 deg. Period: 718.00 min. Global Positioning System. Placed in Plane C Slot 3..

1993 May 13

00:07 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 91 - . Payload: GPS 2A-20 / GPS SVN 37. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22657 . COSPAR: 1993-032A. Apogee: 20,345 km (12,641 mi). Perigee: 20,017 km (12,437 mi). Inclination: 55.10 deg. Period: 718.00 min. Global Positioning System. Placed in Plane C Slot 4..

1993 June 26

13:27 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 92 - . Payload: GPS 2A-21 / GPS SVN 39. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22700 . COSPAR: 1993-042A. Apogee: 20,250 km (12,580 mi). Perigee: 20,112 km (12,496 mi). Inclination: 54.60 deg. Period: 717.90 min. Global Positioning System. Placed in Plane A Slot 1..

1993 August 30

12:38 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 94 - . Payload: GPS 2A-22 / GPS SVN 35. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22779 . COSPAR: 1993-054A. Apogee: 20,255 km (12,585 mi). Perigee: 20,110 km (12,490 mi). Inclination: 54.90 deg. Period: 718.00 min. Global Positioning System. Placed in Plane B Slot 4..

1993 October 26

17:04 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 96 - . Payload: GPS 2A-23 / GPS SVN 34. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 22877 . COSPAR: 1993-068A. Apogee: 20,260 km (12,580 mi). Perigee: 20,104 km (12,492 mi). Inclination: 55.10 deg. Period: 718.00 min. Global Positioning System. Placed in Plane D Slot 4..

1994 March 10

03:40 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 100 - . Payload: GPS 2A-24 / GPS SVN 36. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 23027 . COSPAR: 1994-016A. Apogee: 20,366 km (12,654 mi). Perigee: 20,000 km (12,000 mi). Inclination: 53.90 deg. Period: 718.00 min. Final element of initial GPS constellation. Placed in Plane C Slot 1..

1996 March 28

00:21 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 117 - . Payload: GPS 2A-25 / GPS SVN 33. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 23833 . COSPAR: 1996-019A. Apogee: 20,257 km (12,587 mi). Perigee: 20,106 km (12,493 mi). Inclination: 54.60 deg. Period: 718.00 min. Placed in Plane C Slot 2 of the constellation..

1996 July 16

00:50 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 126 - . Payload: GPS 2A-26 / GPS SVN 40. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 23953 . COSPAR: 1996-041A. Apogee: 20,237 km (12,574 mi). Perigee: 20,127 km (12,506 mi). Inclination: 55.10 deg. Period: 717.90 min. Placed in Plane E Slot 3 of the constellation..

1996 September 12

08:49 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 128 - . Payload: GPS 2A-27 / GPS SVN 30. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 24320 . COSPAR: 1996-056A. Apogee: 20,320 km (12,620 mi). Perigee: 20,042 km (12,453 mi). Inclination: 54.70 deg. Period: 718.00 min. Placed in Plane B Slot 2 of the constellation..

1997 November 6

00:30 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Delta 7925.
  • USA 134 - . Payload: GPS 2A-28 / GPS SVN 38. Mass: 1,816 kg (4,003 lb). Nation: USA. Agency: USAF. Manufacturer: Seal Beach. Program: Navstar. Class: Navigation. Type: Navigation satellite. Spacecraft Bus: Navstar. Spacecraft: GPS Block 2 and 2A. USAF Sat Cat: 25030 . COSPAR: 1997-067A. Apogee: 20,394 km (12,672 mi). Perigee: 19,970 km (12,400 mi). Inclination: 55.00 deg. Period: 718.00 min. Final GPS Block 2A satellite. Placed in Plane A Slot 3..