Discoverer 27 (Corona/Argon Mission 9020A / KH-5 4), a CIA/NRO film-return mapping/reconnaissance satellite, launched on a Thor DM-21 Agena-B from Vandenberg on 21 July 1961. Range safety destroyed the vehicle during ascent; the payload never reached orbit.
- Outcome
- Failure
- Orbit
- LEO
- Low Earth orbit
- Payload to orbit
- Did not reach orbit
- Flight
- 12th
- of 40 Thor DM-21 Agena-B flights
- Date and time
- 21 July 1961, 22:35 UTC
- Rocket
- Thor DM-21 Agena-B
- Builder
- McDonnell Douglas
- Launch site
- Space Launch Complex 1W, Vandenberg SFB, CA, USA
- Payload
- Government/Top Secret
- Launches in 1961
- 25th of 50