The Weston satellite was part of a series of so called Program 11 or P-11 "Subsatellite Ferrets", low orbit ELINT/SIGINT satellites to pinpoint and characterize different Radar emitters in the Soviet Union and Warsaw pact states.
The first P-11s had essentially nondirectional antennas and were intended to collect specific emitters, primarily to obtain textual content of the intercept data. These were directed-coverage missions, which included Pundit and Savant for on-pad and launch telemetry and Weston for radio teletype and voice content of the Soviet VHF and UHF point-to-point communications system.
The Weston COMINT payload was sophisticated version of the Aftrack payload Opporknockity. Although tested before flight from aircraft, the communications signals it collected were still troubled by interference. Nevertheless Weston did produce useful data. Weston's mission was to intercept, recognize, and record Mercury Grass and Dawn Rose communications signals in the 60 to 70 MHz and the 360 to 420 MHz frequency bands. It measured the frequency and power of the intercepted signal, but would not geolocate the targets. It had two antennas, a UHF “oil derrick antenna” and a VHF “window shade” antenna, named for their appearance, and both stored in the same box on the side of the satellite. Two covers would be ejected off the box allowing the antennas to deploy. These antennas led to a UHF and two VHF superheterodyne receivers. The outputs of the receivers were recorded on tape recorders. When the tape recorders played back their information, the signals were analog-to-digital converted, enciphered, and transmitted to a tracking station in the United States.
The satellites were based on Lockheed's P-11 bus, which was designed to fit on the aft rack of the Agena-D upper stage. The bus contained each one or two focused payload black boxes and different antenna configurations according to payload, as well as deployable solar arrays. The satellite featured two solid rocket motors, which allowed them to rise and circularize their orbit after deployment from the host satellite. Both spin or gravity gradient stabilization was possible.
This subsatellite was deployed from the propulsion rack of an Agena-D stage, which launched a number of small satellites. It used two solid-fuel kick-motors to maneuver itself into its operational orbits after deployment.
|Type / Application:||SIGINT, COMINT|
|Operator:||US Air Force (USAF)|
|Contractors:||Lockheed (bus); Haller/Raymond/Brown Division of Singer (payload)|
|Power:||Solar cells, batteries|
|Lifetime:||9 months (design)|
|Orbit:||442 km × 477 km, 69.65°|
|Weston (P-11 4407, Mission 7313, OPS 1807)||1969-082A||30.09.1969||Va SLC-1W||Thorad-SLV2G Agena-D||with Poppy 8A, Poppy 8B, Poppy 8C, Poppy 8D, Timation 2, Tempsat 2, SOICAL Cone, SOICAL Cylinder, NRL-PL 176|