DSCS III
Defense Satellite Communications System III
Part of the DSCS (Defense Satellite Communications System) program

DSCS provides secure voice and data communications for the US military. The contract is managed by the DCA (Defense Communications Agency) for the USAF. Recurring cost is quoted as $160 million in Aviation Week (8/7/95).

Spacecraft
3-axis stabilization (0.1 deg control in pitch, roll) using reaction wheels, earth and sun sensors. Two articulated solar arrays produce 1240 W (BOL), NiCd batteries with 105 AHr, 28V bus. S-Band (SGLS) and X-Band command and telemetry links. Blowdown hydrazine propulsion system with 16 x 1-lbf thrusters.

Payload
Six SHF channels. Ch1: 50 MHz, 40 W; Ch2: 75 MHz, 40 W; Ch3: 85 MHz, 10 W; Ch4: 85 MHz, 10 W; Ch5: 60 MHz, 10 W; Ch6: 50 MHz, 10 W. Full Earth and narrow coverage capabilities. Receive antennas: two Earth coverage horns, one steerable 61-beam nulling lens. Transmit antennas: two Earth coverage horns, two steerable 19-beam wave guide lens, one high gain parabolic gimballed dish.

Country of Origin	United States
Customer/User	USAF
Manufacturer(s)	GE Astro Space
Size	2.1 x 1.9 x 2.0 m bus, 11.5 m solar array span
Orbit	Geosynchronous
Design Life	10 years

Launch Facts

Name	Int'l Desig.	Date	Site	Vehicle	Orbit	Mass(kg)
Notes
DSCS 3 F1	1982-106B	10/30/82	ESMC	Titan 34D IUS	GEO
Defense Satellite Communications System
DSCS 3 F2 (USA 11)	1985-092C ?	10/3/85	ESMC	STS 51J	GEO
Defense Satellite Communications System; released from STS 51J 10/4/85; boosted into orbit with DSCS 3 F3 on single IUS booster
DSCS 3 F3 (USA 12)	1985-092D ?	10/3/85	ESMC	STS 51J	GEO
Defense Satellite Communications System; released from STS 51J 10/4/85; boosted into orbit with DSCS 3 F2 on single IUS booster
DSCS 3 F4 (USA 44)	1989-069B	9/4/89	ESMC	Titan 34D	GEO
Defense Satellite Communications System
DSCS 3 F7 (USA 93)	1993-046A	7/19/93	ESMC	Atlas 2	GEO	2615
Defense Satellite Communications System
DSCS 3 F8 (USA 97)	1993-074A	11/28/93	ESMC	Atlas 2	GEO	2615
Defense Satellite Communications System
DSCS 3 F9 (USA 113)	1995-038A	7/31/95	ESMC	Atlas 2A	GEO	2610
Defense Satellite Communications System