Canyon 4 (AFP-827), a U.S. Air Force SIGINT reconnaissance satellite intended for geosynchronous orbit. Atlas SLV-3A Agena-D from Cape Canaveral LC-13 failed on 4 December 1971 when a sustainer gas-generator fault forced range-safety destruct about 62 seconds after liftoff.
- Outcome
- Failure
- Orbit
- Direct-GEO
- Geostationary orbit
- Payload to orbit
- Did not reach orbit
- Flight
- 6th
- of 12 Atlas SLV-3A Agena D flights
- Date and time
- 4 December 1971, 22:33 UTC
- Rocket
- Atlas SLV-3A Agena D
- Builder
- Convair
- Launch site
- Space Launch Complex 13, Cape Canaveral SFS, FL, USA
- Payload
- Government/Top Secret
- Launches in 1971
- 118th of 133