CANYON
CANYON was the code name for an early series of COMINT (Communication Intelligence) satellites, managed by the NRO and operated by the U.S. Air Force. Its unclassified numerical designation was Program 827. The primary task of CANYON was to listen to Soviet microwave links and VHF communications. The satellites were launched by Atlas-Agena D launch vehicles, and placed in near-geosynchronous 24h orbits. In such orbits, satellites stay above a certain area on the ground, allowing continuous listening over the area in view, while at the same time drifting slowly over the Earth's surface so that pinpointing of sources via triangulation is possible. There is no confirmed information about the physical characteristics of the CANYON satellites, but they were reportedly equipped with a large receiver dish antenna of about 10 m diameter.
The first CANYON mission was launched on 6 August 1968, but early in the flight the satellite was lost because of an erroueous command from the ground control station. The second and third CANYON satellites delivered data, but didn't work very reliably, often cutting out transmissions to the receiving stations or not transmitting at all. After a launch failure on the 4th flight, the remaining three CANYON satellites finally lived up to expecations and worked as designed. In the late 1970s, CANYON was succeeded by the CHALET/VORTEX series of satellites.
CANYON Launch List
- No.: Sequential flight number for the CANYON program
- Name: Unclassified name of the satellite. The OPS number ("OPS" standing for "Operations") is a random number given to all military-related satellite launches between 1963 and May 1984 (when "OPS" was replaced by a sequential "USA" number).
- Mission: Each CANYON mission had a unique serial number in the 75xx range. The whole CANYON program was also labeled "Mission 7500".
- COSPAR ID: International designation of the satellite; not applicable, if orbit was not reached
| No. | Name | Mission | COSPAR ID | Launch | Launch Vehicle |
|---|---|---|---|---|---|
| 1 | OPS 2222 | 7501 | 1968-063A | 6 Aug 1968 | SLV-3A Atlas-Agena D |
| 2 | OPS 3148 | 7502 | 1969-036A | 13 Apr 1969 | SLV-3A Atlas-Agena D |
| 3 | OPS 7329 | 7503 | 1970-069A | 1 Sep 1970 | SLV-3A Atlas-Agena D |
| 4 | - | 7504 | Launch failure | 4 Dec 1971 | SLV-3A Atlas-Agena D |
| 5 | OPS 9390 | 7505 | 1972-101A | 20 Dec 1972 | SLV-3A Atlas-Agena D |
| 6 | OPS 4966 | 7506 | 1975-055A | 18 Jue 1975 | SLV-3A Atlas-Agena D |
| 7 | OPS 9751 | 7507 | 1977-038A | 23 May 1977 | SLV-3A Atlas-Agena D |
CANYON launches
Main Sources
[1] Jeffrey T. Richelson: Eavesdroppers
in Disguise, Air Force Magazine, August 2012
[2] Gunter Krebs: Gunter's Space Page (for launch lists)
Back to Directory of U.S. Military Rockets and Missiles, Appendix 3
Last Updated: 27 June 2025