Intelsat III F-8
{{Short description|Failed communications satellite}}
{{Use American English|date=April 2017}}
{{Infobox spaceflight
| name = Intelsat III F-8
| image =
| image_alt =
| image_caption =
| mission_type = Communications
| operator = Intelsat
| website =
| COSPAR_ID = 1970-055A
| SATCAT = 04478
| mission_duration = 5 years (planned)
Launch failure
| spacecraft_bus =
| spacecraft_type =
| manufacturer = TRW
| BOL_mass = {{convert|151|kg|lb}}
| launch_mass = {{convert|293|kg|lb}}
| dimensions =
| power = 183 W
| launch_date = {{start-date|July 23, 1970, 00:16:03|timezone=yes}} UTC{{cite web|url=http://planet4589.org/space/log/launchlog.txt|title=Launch Log|first=Jonathan|last=McDowell|work=Jonathan's Space Page|access-date=April 21, 2017}}
| launch_rocket = Delta M
| launch_site = Cape Canaveral LC-17A
| launch_contractor =
| disposal_type =
| deactivated =
| orbit_epoch = July 23, 1970{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1970-055A|title=INTELSAT 3 F-8|first=Goddard Space Flight Center|last=NASA|work=NSSDC Master Catalog|access-date=April 21, 2017}}
| orbit_reference = Geocentric
| orbit_regime = Geostationary
| orbit_periapsis = {{convert|19,400|km|mi|sp=us}}
| orbit_apoapsis = {{convert|36,030|km|mi|sp=us}}
| orbit_eccentricity = 0.24386
| orbit_period = 1,043.0 minutes
| orbit_longitude =
| apsis = gee
| trans_band =
| trans_frequency =
| trans_bandwidth =
| trans_capacity =
| trans_coverage =
| trans_TWTA =
| trans_EIRP =
| trans_HPBW =
| programme = Intelsat III
| previous_mission = Intelsat III F-7
| next_mission = Intelsat IV F-1 (Intelsat IV)
}}
Intelsat III F-8 was a communications satellite owned by Intelsat. The satellite had an estimated useful life of 5 years.
Design
The last of eight Intelsat III satellites to be launched, Intelsat III F-8 was built by TRW. It was a {{convert|293|kg|lb|adj=on}} spacecraft equipped with two transponders to be powered by body-mounted solar cells generating 183 watts of power.{{cite encyclopedia|url=http://www.astronautix.com/craft/intlsat3.htm|archive-url=https://web.archive.org/web/20020223094128/http://www.astronautix.com/craft/intlsat3.htm|url-status=dead|archive-date=February 23, 2002|title=Intelsat 3|first=Mark|last=Wade|encyclopedia=Encyclopedia Astronautica|access-date=April 21, 2017}} It had a design life of five years and carried an SVM-2 apogee motor for propulsion.{{cite web|url=http://space.skyrocket.de/doc_sdat/intelsat-3.htm|title=Intelsat-3|first=Gunter|last=Krebs|work=Gunter's Space Page|access-date=April 21, 2017}}
Launch
Intelsat III F-8 was launched on a Delta M rocket, flying from Launch Complex 17A at the Cape Canaveral Air Force Station. The launch took place on July 23, 1970, with the spacecraft bound for a geosynchronous transfer orbit.
The Intelsat III F-8 was lost due to a malfunction during the apogee motor firing. Communications stopped 14.5 seconds into the planned 27 second apogee motor burn.
See also
{{Portal|Spaceflight}}