Intelsat IV F-7

Mission type	Communications
Operator	Intelsat
COSPAR ID	1973-058A
SATCAT no.	06796
Mission duration	7 years (planned)
Spacecraft properties
Bus	HS-312
Manufacturer	Hughes Aircraft
Launch mass	1,414 kilograms (3,117 lb)
BOL mass	730 kilograms (1,610 lb)
Start of mission
Launch date	August 23, 1973, 22:57:02 (1973-08-23UTC22:57:02Z) UTC[1]
Rocket	Atlas SLV-3D Centaur-D1AR
Launch site	Cape Canaveral LC-36A
Orbital parameters
Reference system	Geocentric[2]
Regime	Geostationary[2]
Eccentricity	0.72066[2]
Perigee altitude	597 kilometers (371 mi)[2]
Apogee altitude	36,612 kilometers (22,750 mi)[2]
Inclination	27.5°[2]
Period	655.2 minutes[2]
Epoch	August 23, 1973[2]
Transponders
Band	12 IEEE C-band
Bandwidth	40 MHz
Intelsat IV ← Intelsat IV F-6 Intelsat IV F-8 →

Intelsat IV F-7 was a geostationary communication satellite built by Hughes, it was owned by Intelsat. The satellite was based on the HS-312 platform and its estimated useful life was seven years.

History

The Intelsat IV F-7 was part of the Intelsat IV series which consisted of eight communications satellites, launched from Cape Canaveral during the early 1970s, marked the fifth generation of geostationary communications satellites developed by the Hughes Aircraft Company since 1963 with the launch of Syncom II, the world's first synchronous satellite. The Syncom II was 15 cm high and 28 inches in diameter, weighing 78 pounds in orbit. In contrast, the Intelsat IVs weighed more than £ 1,300 (595 kg) into orbit and were more than 17 feet (5.2 meters) in diameter. All seven satellites exceeded their projected life expectancies and were withdrawn from active duty, the last of which, the Intelsat IV F-1 was retired in October 1987.

The satellite was equipped with 12 C-band transponders. It had 6,000 two-way relay phone calls or broadcast 12 concurrent color television programs or mixed combinations of communications traffic including data and fax.

The satellite had 12 channels of broadband communication. Each channel had a bandwidth of 40 MHz and provided about 500 communication circuits.

Launch

The satellite was successfully launched into space on August 23, 1973, at 23:57:02 UTC, by means of an Atlas-Centaur vehicle from the Cape Canaveral Air Force Station, United States. It had a launch mass of 1,414 kg.^[3]