GPS Block 2 and 2A

Part of the Global Positioning System (GPS) program

GPS Block 2 is the Operational system, following the Demonstration system comprised of Block 1 spacecraft. The Block 2A are "Advanced" versions of this spacecraft. The complete constellation has 24 spacecraft in 6 high-altitude orbit planes.

Spacecraft
3-Axis stabilized, nadir pointing using reaction wheels. Dual solar arrays supply 710 watts (EOL). S-Band (SGLS) communications for control and telemetry. UHF cross-link between spacecraft. Hydrazine propulsion system.

Payload
Two L-Band navigation signals at 1575.42 MHz (L1) and 1227.60 MHz (L2). Each spacecraft carries 2 rubidium and 2 cesium clocks. Also carry nuclear detonation detection sensors.

Country of Origin	United States
Customer/User	U.S. Air Force
Manufacturer(s)	Rockwell Space Systems
Size	5.3 m across with solar panels deployed
Orbit	20,200 km circular (12 hour period) 55 deg inclination, 6 orbit planes
Design Life	7.5 years

Launch Facts

Name	Int'l Desig.	Date	Site	Vehicle	Orbit	Mass(kg)
Notes
GPS 2-1 (USA 35)	1989-013A	2/14/89	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-2 (USA 38)	1989-044A	6/10/89	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-3 (USA 42)	1989-064A	8/18/89	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-4 (USA 47)	1989-085A	10/21/89	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-5 (USA 49)	1989-097A	12/11/89	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-6 (USA 50)	1990-008A	1/24/90	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-7 (USA 54)	1990-025A	3/26/90	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-8 (USA 63)	1990-068A	8/2/90	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-9 (USA 64)	1990-088A	10/1/90	ESMC	Delta 6925	MEO	1665
2nd generation Global Positioning System
GPS 2-10 (USA 66)	1990-103A	11/26/90	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-11 (USA 71)	1991-047A	7/4/91	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-12 (USA 79)	1992-009A	2/23/92	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-13 (USA 80)	1992-019A	4/10/92	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-14 (USA 83)	1992-039A	7/7/92	ESMC	Delta 7925	MEO	1165
2nd generation Global Positioning System
GPS 2-15 (USA 84)	1992-058A	9/9/92	ESMC	Delta 7925	MEO	1165
2nd generation Global Positioning System
GPS 2-16 (USA 85)	1992-079A	11/22/92	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-17 (USA 87)	1992-089A	12/18/92	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-18 (USA 88)	1993-007A	2/3/93	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-19 (USA 90)	1993-017A	3/30/93	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-20 (USA 91)	1993-032A	5/13/93	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-21 (USA 92)	1993-042A	6/26/93	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-22 (USA 94)	1993-054A	8/30/93	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-23 (USA 96)	1993-068A	10/26/93	ESMC	Delta 7925	MEO	1665
2nd generation Global Positioning System
GPS 2-24 (USA 100)	1994-016A	3/10/94	ESMC	Delta 2	MEO	1665
2nd generation Global Positioning System; final element of initial GPS constellation
GPS 2-25 (USA 117)	1996-019A	3/28/96	ESMC	Delta 2	MEO	1665
2nd generation Global Positioning System
GPS 2-26 (USA 126)	1996-041A	7/16/96	ESMC	Delta 2	MEO	1665
2nd generation Global Positioning System
GPS 2-27 (USA 128)	1996-056A	9/12/96	ESMC	Delta 2	MEO	1665
2nd generation Global Positioning System