Westar

Part of the Westar program

The Westar series of geostationary spacecraft provide commercial communications services for Western Union. Westar 6 failed to achieve geosynchronous orbit after being deployed from the Space Shuttle. It was later retrieved by another Shuttle mission (November 14, 1984) and returned for refurbishment and relaunch. All Westars have been launched by NASA on a reimbursable basis.

Spacecraft
Westar uses the Hughes HS-376 spacecraft design. Spin stabilized with a despun antenna section. Body mounted solar cells. Once on orbit, an outer cylinder deploys downward in "dixie-cup" fashion to increase the solar panel area.

Payload
Westar spacecraft typically carried 12 to 24 transponders in the 4-6 GHz range. A single antenna reflector (72 inch diameter) is used with an array of offset feed horns. The reflector uses two polarization-selective surfaces for horizontal and vertical polarized signals.

Country of Origin	United States
Customer/User	Western Union
Size	F1-3: 75 inch diameter x 135 inch high F4-6 (HS-376): 85 inch diameter x 108 inch high (260 inch deployed)
Orbit	Geosynchronous
Design Life	10 years

Launch Facts

Name	Int'l Desig.	Date	Site	Vehicle	Orbit	Mass(kg)
Notes
Westar 1	1974-022A	4/13/74	ESMC	Delta 2914	GEO	500
Westar 2	1974-075A	10/10/74	ESMC	Delta 2914	GEO	500
Westar 3	1979-072A	8/10/79	ESMC	Delta 2914	GEO	572
Westar 4	1982-014A	2/26/82	ESMC	Delta 3910	GEO	1072
TV, telephone
Westar 5	1982-058A	6/9/82	ESMC	Delta 3910	GEO	1072
Voice, TV coverage for Alaska, Hawaii, Puerto Rico, Virgin Islands
Westar 6	1984-011B	2/3/84	ESMC	STS 41B	LEO	1200
Deployed from STS 41B 2/4/84; failed to reach proper orbit; recovered by STS-51A