Intelsat III F-8


Intelsat III F-8
Mission typeCommunications
COSPAR ID1970-055A
SATCAT no.04478
Mission duration5 years (planned)
Launch failure
Spacecraft properties
Launch mass293 kilograms (646 lb)
BOL mass151 kilograms (333 lb)
Power183 W
Start of mission
Launch dateJuly 23, 1970, 00:16:03 (1970-07-23UTC00:16:03Z) UTC[1]
RocketDelta M
Launch siteCape Canaveral LC-17A
Orbital parameters
Reference systemGeocentric[2]
Perigee altitude19,400 kilometers (12,100 mi)[2]
Apogee altitude36,030 kilometers (22,390 mi)[2]
Period1,043.0 minutes[2]
EpochJuly 23, 1970[2]
Intelsat III
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.


The last of eight Intelsat III satellites to be launched, Intelsat III F-8 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.[3] It had a design life of five years and carried an SVM-2 apogee motor for propulsion.[4]


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.[1]

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


  1. ^ a b McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved April 21, 2017.
  2. ^ a b c d e f g h NASA, Goddard Space Flight Center. "INTELSAT 3 F-8". NSSDC Master Catalog. Retrieved April 21, 2017.
  3. ^ Wade, Mark. "Intelsat 3". Encyclopedia Astronautica. Retrieved April 21, 2017.
  4. ^ Krebs, Gunter. "Intelsat-3". Gunter's Space Page. Retrieved April 21, 2017.