| Mission type | Communications |
|---|---|
| Operator | Intelsat |
| COSPAR ID | INT4F-6 |
| Mission duration | 7 years (planned) (Launch failure) |
| 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 | February 20, 1975, 23:35 UTC [1] |
| Rocket | Atlas SLV-3D Centaur-D1 AR |
| Launch site | Cape Canaveral LC-36A |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Geostationary |
| Epoch | Planned |
Intelsat IV | |
Intelsat IV F-6 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 7 years.
The Intelsat IV F-6 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 All seven satellites exceeded their projected life expectancies and were withdrawn from active duty, the last of which, the Intelsat IV F-1 was retired in October 1987.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.
The satellite was lost due to a launcher malfunction. [2]
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit 22,300 miles (35,900 km) above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently.
Syncom started as a 1961 NASA program for active geosynchronous communication satellites, all of which were developed and manufactured by the Space and Communications division of Hughes Aircraft Company. Syncom 2, launched in 1963, was the world's first geosynchronous communications satellite. Syncom 3, launched in 1964, was the world's first geostationary satellite.
Intelsat I was the first commercial communications satellite to be placed in geosynchronous orbit, on April 6, 1965. It was built by the Space and Communications Group of Hughes Aircraft Company for COMSAT, which activated it on June 28, 1965. It was based on the Syncom series of satellites that Hughes had previously built for NASA to demonstrate that communications via synchronous-orbit satellite were feasible. Its booster was a Thrust Augmented Delta. After a series of maneuvers, it reached its geosynchronous orbital position over the Atlantic Ocean at 28° West longitude, where it was put into service.
Marisat satellites were the first maritime telecommunications satellites and were designed to provide dependable telecommunications for commercial shipping and the U.S. Navy from stable geosynchronous orbital locations over the three major ocean regions. The three Marisat satellites, F1, F2, and F3, were built by Hughes Aircraft Corporation (HAC) for COMSAT Corporation starting in 1973. The satellites were designed to provide maritime telecommunications services in three large ocean areas, the Atlantic Ocean, the Pacific Ocean, and the Indian Ocean, and were located at 72.5° East longitude, 176.5° E, and 345° E in the geosynchronous orbital arc. The three-satellite Marisat system served as the initial INMARSAT constellation.
Intelsat 603 or IS-603, previously named Intelsat VI F-3, is a communications satellite operated by Intelsat. Launched in 1990, it was the second of five Intelsat VI satellites to be launched. The Intelsat VI series was constructed by Hughes Aircraft, based on the HS-389 satellite bus.
Orion 3 was an American spacecraft which was intended for use by Orion Network Systems, as a geostationary communications satellite. It was to have been positioned in geostationary orbit at a longitude of 139° East, from where it was to have provided communications services to Asia and Oceania. Due to a malfunction during launch, it was instead delivered to a useless low Earth orbit.
Intelsat II was a series of four communications satellites operated by Intelsat which were launched in 1966 and 1967. Built by the Hughes Aircraft Company, the Intelsat II series was a follow-up to the Intelsat I series, of which only one satellite was launched.
Intelsat II F-2, also known as Lani Bird, was a communications satellite operated by Intelsat. Launched in 1967, it was operated in geostationary orbit at a longitude of 174 degrees east until 1969.
Intelsat II F-3, also known as Canary Bird was a communications satellite operated by Intelsat. Launched in 1967 it was operated in geostationary orbit, spending most of its operational life at a longitude of 15 degrees west.
Intelsat III F-3 was a geostationary communications satellite operated by Intelsat. Launched in 1969 it was intended for operations over the Pacific Ocean; however, it spent most of its service life over the Indian Ocean at a longitude of 63 degrees east.
Intelsat IV F-1 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 7 years.
Intelsat IV F-2 was a geostationary communication satellite built by Hughes and owned by Intelsat. The satellite was based on the HS-312 platform and its estimated useful life was 7 years.
Intelsat IV F-3 was a geostationary communication satellite built by Hughes, it was owned by Intelsat. The satellite was based on the HS-353 platform and its estimated useful life was 7 years.
Intelsat IV F-4 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 7 years.
Intelsat IV F-5 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 7 years.
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.
Intelsat IV F-8 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 7 years.
Intelsat IVA F-2 was a geostationary communication satellite built by Hughes, it was owned by Intelsat. The satellite was based on the HS-353 platform and its estimated useful life was 7 years.
Intelsat IVA F-3 was a geostationary communication satellite built by Hughes, it was owned by Intelsat. The satellite was based on the HS-353 platform and its estimated useful life was 7 years.
Intelsat IVA F-6 was a geostationary communication satellite built by Hughes, it was owned by Intelsat. The satellite was based on the HS-353 platform and its estimated useful life was 7 years.
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