Intelsat III F-1


Intelsat III F-1
Mission typeCommunications
Mission duration5 years planned
Failed to orbit
Spacecraft properties
Spacecraft typeIntelsat III
Launch mass293 kilograms (646 lb)
Power183 watts
Start of mission
Launch dateSeptember 19, 1968, 00:09:00 (1968-09-19UTC00:09Z) UTC[1]
RocketDelta M
Launch siteCape Canaveral LC-17A
Orbital parameters
Reference systemGeocentric
Intelsat III

Intelsat III F-1 was a communications satellite intended to be operated by Intelsat. Launched towards geostationary orbit in 1968 it failed to achieve orbit.


Launch of Intelsat III F-1.

The first of eight Intelsat III satellites to be launched, Intelsat III F-1 was built by TRW. It was a 293-kilogram (646 lb) spacecraft equipped with two transponders to be powered by body-mounted solar cells generating 183 watts of power.[2] It had a design life of five years and carried an SVM-2 apogee motor for propulsion..[3]


Intelsat III F-1 was launched on the maiden flight of the Delta M rocket, flying from Launch Complex 17A at the Cape Canaveral Air Force Station. The launch took place at 00:09:00 UTC on September 19, 1968, with the spacecraft bound for a geosynchronous transfer orbit.[1]

It was to go in operation above the Atlantic Ocean in time to relay broadcasts of the next month's Olympics in Mexico City.[4][5][6]

Twenty seconds after liftoff a fault became apparent in the gyroscope used to monitor the rate at which the rocket pitched over. Control of the rocket was subsequently lost, with it beginning to disintegrate around 102 seconds into the flight.[7] At 108 seconds after launch the rocket was destroyed by range safety.[8]

See also


  1. ^ a b McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved February 9, 2014.
  2. ^ Wade, Mark. "Intelsat 3". Encyclopedia Astronautica. Retrieved February 9, 2014.
  3. ^ Krebs, Gunter. "Intelsat-3". Gunter's Space Page. Retrieved February 9, 2014.
  4. ^ "Rocket explodes after launch; new satellite lost". St. Petersburg Times. (Florida). UPI. September 19, 1968. p. 11A.
  5. ^ "Blast ends orbit try for satellite". Spokesman-Review. (Spokane, Washington). Associated Press. September 19, 1968. p. 1.
  6. ^ "Olympic relay satellite is blown up". Milwaukee Sentinel. UPI. September 19, 1968. p. 1, part 1.
  7. ^ Kyle, Ed. "Long Tank Thor-Delta". Space Launch Report. Retrieved February 9, 2014.
  8. ^ Kyle, Ed. "Thor-Based Space Launch History". Space Launch Report. Retrieved February 9, 2014.