| Auto: | all |
| Intelsat III F-3 | |
| Mission Type: | Communications |
| Operator: | Intelsat |
| Cospar Id: | 1969-011A |
| Satcat: | 03674 |
| Mission Duration: | 5 years |
| Spacecraft Type: | Intelsat III |
| Manufacturer: | TRW |
| Launch Mass: | 293kg (646lb) |
| Bol Mass: | 151kg (333lb) |
| Power: | 183 watts |
| Launch Date: | UTC[1] |
| Launch Rocket: | Delta M |
| Launch Site: | Cape Canaveral LC-17A |
| Launch Contractor: | NASA[2] |
| Disposal Type: | Decommissioned |
| Deactivated: | c. |
| Orbit Epoch: | January 23, 2015, 15:01:00 UTC[3] |
| Orbit Reference: | Geocentric |
| Orbit Regime: | Geosynchronous Now Graveyard |
| Orbit Periapsis: | 39921km (24,806miles) |
| Orbit Apoapsis: | 41534km (25,808miles) |
| Orbit Inclination: | 18.33 degrees |
| Orbit Semimajor: | 47100km (29,300miles) |
| Orbit Period: | 1695.49 minutes |
| Orbit Longitude: | 174° east (1969) 63° east (1969-c.1975) |
| Apsis: | gee |
| Programme: | Intelsat III |
| Previous Mission: | Intelsat III F-2 |
| Next Mission: | Intelsat III F-4 |
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.[4]
The third of eight Intelsat III satellites to be launched, Intelsat III F-3 was built by TRW. It was a 293kg (646lb) spacecraft, with its mass reducing to 151kg (333lb) by entry into service as it burned propellant to reach its final orbit. The satellite carried an SVM-2 apogee motor for propulsion and was equipped with two transponders powered by body-mounted solar cells generating 183 watts of power.[5] It was designed for 5 years of service life.[6]
The launch of Intelsat III F-3 made use of a Delta M rocket flying from Launch Complex 17A at the Cape Canaveral Air Force Station. The launch, which was conducted by NASA, took place at 00:39:00 UTC on February 6, 1969, with the spacecraft entering a geosynchronous transfer orbit.[1] Shortly after launch, Intelsat III F-3 fired its apogee motor to achieve geostationary orbit.
Intended to be operated over the Pacific Ocean at a longitude of 174° east, Intelsat III F-3 was moved to the less important Indian Ocean slot at 63° east after only three months in orbit due to concerns regarding its reliability. The satellite was only regarded as partially operable; however, it remained in service until April 1979, before being decommissioned in December of that year.[7] [8]
At the end of its service life, Intelsat III F-3 was raised into a higher orbit to reduce the probability of it colliding with an operational spacecraft. As of February 3, 2014 it remains in orbit, with a perigee of 39935km (24,814miles), an apogee of 41521km (25,800miles), inclination of 18.63 degrees and an orbital period of 28.25 hours.[3]