SSF

Class: SIGINT. Destination: Medium Earth Orbit. Nation: USA. Agency: U.S. Air Force.

Subsatellite ferrets were a series of heavily classified small satellites, released in association with other military launches, that undertook radio and radar signals intelligence gathering. There seem to have been several types, but all details remain secret.

Typical orbit: 506 x 752 km, 92.5 deg inclinaton. Associated Launch Vehicle: Atlas LV-3A / Agena D, Shuttle, SLV-3 Atlas / Agena D, Thor Agena D SLV-2A, Thorad Agena D SLV-2G, Thorad Agena D SLV-2H, Titan 34D, Titan 3D.

SSF Chronology

1963 December 21 - Hitch Hiker 3 - Launch Site: Vandenberg. Launch Vehicle: Thor Agena D. Mass: 80 kg (176 lb). Perigee: 316 km (196 mi). Apogee: 394 km (244 mi). Inclination: 64.50 deg. Period: 91.70 min.
Radar monitoring.

1963 June 27 - Hitch Hiker 1 - Launch Site: Vandenberg. Launch Vehicle: Thor Agena D. Mass: 80 kg (176 lb). Perigee: 323 km (200 mi). Apogee: 2,506 km (1,557 mi). Inclination: 82.10 deg. Period: 114.10 min.
Radiation data. First successful flight of P-11 bus, mainly used for radar signals intelligence gathering.

1963 March 18 - P-11 No. 1 - Launch Site: Vandenberg. Launch Vehicle: Thor Agena D. FAILURE: Failure. Mass: 80 kg (176 lb).
Ferret subsatellite aboard first launch of KH-6. Mission failed.

1963 October 29 - Hitch Hiker 2 - Launch Site: Vandenberg. Launch Vehicle: Thor Agena D. Mass: 80 kg (176 lb). Perigee: 288 km (178 mi). Apogee: 581 km (361 mi). Inclination: 90.00 deg. Period: 93.30 min.
Radar monitoring.

1964 August 14 - OPS 3316 - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 79 kg (174 lb). Perigee: 272 km (169 mi). Apogee: 3,751 km (2,330 mi). Inclination: 95.70 deg. Period: 127.40 min.

1964 July 6 - OPS 4923 - Launch Site: Point Arguello. Launch Vehicle: Atlas LV-3A / Agena D. Mass: 80 kg (176 lb). Perigee: 156 km (96 mi). Apogee: 505 km (313 mi). Inclination: 92.90 deg. Period: 91.10 min.
Radar monitoring.

1964 October 23 - OPS 5063 - Launch Site: Vandenberg. Launch Vehicle: Atlas LV-3A / Agena D.

1965 April 28 - OPS 6717 - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 506 km (314 mi). Apogee: 547 km (339 mi). Inclination: 95.20 deg. Period: 95.10 min.
Radar monitoring.

1965 August 3 - OPS 6761 - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 501 km (311 mi). Apogee: 515 km (320 mi). Inclination: 107.40 deg. Period: 94.80 min.
Radar monitoring.

1965 June 25 - OPS 6749 - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 496 km (308 mi). Apogee: 510 km (310 mi). Inclination: 107.60 deg. Period: 94.70 min.
Radar monitoring.

1965 November 8 - OPS 6232/Agena D - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 155 km (96 mi). Apogee: 284 km (176 mi). Inclination: 93.90 deg. Period: 88.90 min.
Not identified as a subsatellite ferret by McDowell.

1966 August 16 - OPS 6810 - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 511 km (317 mi). Apogee: 522 km (324 mi). Inclination: 93.20 deg. Period: 94.90 min.
Radar monitoring.

1966 January 19 - OPS 3179/Agena D - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 120 km (70 mi). Apogee: 149 km (92 mi). Inclination: 93.80 deg. Period: 87.20 min.
Not identified as a subsatellite ferret by McDowell.

1966 June 3 - OPS 1856/Agena D - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 148 km (91 mi). Apogee: 230 km (140 mi). Inclination: 86.90 deg. Period: 88.20 min.
Not identified as a subsatellite ferret by McDowell.

1966 March 18 - OPS 0974/Agena D - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 2,000 kg (4,400 lb). Perigee: 149 km (92 mi). Apogee: 285 km (177 mi). Inclination: 101.00 deg. Period: 88.80 min.
Space craft engaged in investigation of spaceflight techniques and technology (US Cat A).

1966 May 14 - OPS 6785 - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 519 km (322 mi). Apogee: 555 km (344 mi). Inclination: 110.00 deg. Period: 95.40 min.
Radar monitoring.

1966 November 2 - OPS 5424/Agena D - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 208 km (129 mi). Apogee: 324 km (201 mi). Inclination: 91.00 deg. Period: 89.90 min.
Not identified as a subsatellite ferret by McDowell.

1966 October 12 - OPS 5345/Agena D - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 181 km (112 mi). Apogee: 258 km (160 mi). Inclination: 90.90 deg. Period: 89.00 min.
Not identified as a subsatellite ferret by McDowell.

1966 September 16 - OPS 6874 - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 60 kg (132 lb). Perigee: 461 km (286 mi). Apogee: 501 km (311 mi). Inclination: 94.10 deg. Period: 94.20 min.
Radar monitoring.

1967 June 16 - OPS 1873 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1967 May 22 - OPS 5557/Agena D - Launch Site: Vandenberg. Launch Vehicle: SLV-3 Atlas / Agena D. Mass: 700 kg (1,540 lb). Perigee: 148 km (91 mi). Apogee: 240 km (140 mi). Inclination: 91.50 deg. Period: 88.40 min.
Not identified as a subsatellite ferret by McDowell.

1967 May 9 - OPS 1967 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G. FAILURE: Failure of the booster cut-off switch.

1967 November 2 - OPS 1587 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1968 December 12 - OPS 7684 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1968 January 24 - OPS 6236 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1968 June 20 - OPS 5259 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1968 March 14 - OPS 7076 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1968 September 18 - OPS 8595 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1969 February 5 - OPS 2644 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1969 March 19 - OPS 2285 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1969 May 2 - OPS 1721 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1969 September 22 - OPS 4710 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G.

1969 September 30 - OPS 1807 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2G. Mass: 60 kg (132 lb). Perigee: 446 km (277 mi). Apogee: 484 km (300 mi). Inclination: 69.60 deg. Period: 93.90 min.

1970 March 4 - OPS 3402 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2H.

1970 May 20 - OPS 8520 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2H. Mass: 60 kg (132 lb). Perigee: 490 km (300 mi). Apogee: 499 km (310 mi). Inclination: 83.10 deg. Period: 94.50 min.
Radar monitoring; may or may not have existed!!!.

1970 November 18 - OPS 6829 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2H.

1971 September 10 - OPS 7681 - Launch Site: Vandenberg. Launch Vehicle: Thorad Agena D SLV-2H.

1972 January 20 - OPS 7719 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 474 km (294 mi). Apogee: 545 km (338 mi). Inclination: 96.00 deg. Period: 94.80 min.
Radar monitoring.

1972 July 7 - OPS 7803 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 498 km (309 mi). Apogee: 504 km (313 mi). Inclination: 96.20 deg. Period: 94.70 min.
Radar monitoring.

1972 October 10 - OPS 8314/2 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 1,420 km (880 mi). Apogee: 1,464 km (909 mi). Inclination: 95.60 deg. Period: 114.70 min.
ABM monitoring.

1973 November 10 - OPS 6630 P/L 2 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 1,414 km (878 mi). Apogee: 1,457 km (905 mi). Inclination: 97.00 deg. Period: 114.60 min.

1973 November 10 - OPS 7705 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 488 km (303 mi). Apogee: 505 km (313 mi). Inclination: 96.30 deg. Period: 94.50 min.
Radar monitoring.

1974 April 10 - OPS 4547 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 503 km (312 mi). Apogee: 531 km (329 mi). Inclination: 94.00 deg. Period: 95.00 min.
Radar monitoring.

1974 October 29 - OPS 6239 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 521 km (323 mi). Apogee: 531 km (329 mi). Inclination: 96.00 deg. Period: 95.10 min.
Radar monitoring; may or may not have existed!!!.

1975 December 4 - KH 9-11 Subsatellite - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 236 km (146 mi). Apogee: 1,558 km (968 mi). Inclination: 96.30 deg. Period: 103.00 min.
Not identified as a subsatellite ferret by McDowell.

1976 July 8 - OPS 5366 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 628 km (390 mi). Apogee: 632 km (392 mi). Inclination: 96.40 deg. Period: 97.30 min.
Radar monitoring.

1978 March 16 - OPS 7858 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 639 km (397 mi). Apogee: 645 km (400 mi). Inclination: 95.80 deg. Period: 97.60 min.
Radar monitoring.

1979 March 16 - OPS 6675 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 621 km (385 mi). Apogee: 628 km (390 mi). Inclination: 95.80 deg. Period: 97.20 min.

1980 June 18 - OPS 1292 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 1,331 km (827 mi). Apogee: 1,333 km (828 mi). Inclination: 96.60 deg. Period: 112.30 min.
ABM monitoring; may or may not have existed!!!.

1982 May 11 - OPS 6553 - Launch Site: Vandenberg. Launch Vehicle: Titan 3D. Mass: 60 kg (132 lb). Perigee: 701 km (435 mi). Apogee: 707 km (439 mi). Inclination: 96.00 deg. Period: 98.90 min.
Radar monitoring; may or may not have existed!!!.

1983 June 20 - OPS 3899 - Launch Site: Vandenberg. Launch Vehicle: Titan 34D. Mass: 60 kg (132 lb). Perigee: 1,278 km (794 mi). Apogee: 1,296 km (805 mi). Inclination: 96.60 deg. Period: 111.31 min.
ABM monitoring; may or may not have existed!!!.

1984 June 25 - USA 3 - Launch Site: Vandenberg. Launch Vehicle: Titan 34D. Mass: 60 kg (132 lb). Perigee: 690 km (420 mi). Apogee: 710 km (440 mi). Inclination: 96.10 deg. Period: 98.80 min.
Radar monitoring.

1986 April 18 - SSF-D No. 6 - Launch Site: Vandenberg. Launch Vehicle: Titan 34D. FAILURE: Failure. Mass: 60 kg (132 lb).

1989 August 8 - USA 41 - Launch Site: Cape Canaveral. Launch Vehicle: Shuttle. Perigee: 296 km (183 mi). Apogee: 307 km (190 mi). Inclination: 57.00 deg. Period: 90.50 min.
Deployed from STS-28 8/8/89. Believed to be one-off ferret satellite under COBRA BRASS measurement and signature intelligence experiment.

Bibliography and Further Reading

JPL Mission and Spacecraft Library, Jet Propulsion Laboratory, 1997. Accessed at: http://msl.jpl.nasa.gov/home.html.

McDowell, Jonathan, Launch Log, October 1998. Jonathan McDowell's complete on-line listing of all objects orbited since Sputnik. Accessed at: http://hea-www.harvard.edu/~jcm/space/log/launch.html.

McDowell, Jonathon, Quest, "US Reconnaissance Satellite Programs Part 2", 1995, Volume 4, Issue 4, page 49.

Krebs, Gunter, Gunter's Space Page, University of Frankfurt, 1996. Accessed at: http://www.skyrocket.de/space.

McDowell, Jonathan, Jonathan's Space Home Page, Harvard University, 1997-present. Jonathan McDowell's complete on-line listing of all objects orbited and over 20,000 rocket launches Accessed at: http://www.planet4589.org/jsr.html.

USAF Satellite Database, USAF Institute of Technology, 1995. Accessed at: ftp://archive.afit.af.mil/pub/space/.

Lockheed Martin Coporation, Atlas Family Fact Sheets, September 1998.. Accessed at: http://www.lmco.com/ILS/txtmain/ils_lsysinfo.htm.

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