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By © Charles P. Vick 2007 All Rights Reserved

06-27-28 ,-07

CHALET/VORTEX - SIGINT Spacecraft Series – ( NRO/USAF/NSA - Program AFP-366)

Code name CHALET/VORTEX the successor to the USAF/NSA-CANYON program was the next in a long series of earth orbit USAF/NSA, SIGINT (signals intelligence) spacecraft used by the USAF for its respective intelligence Communities for a variety of missions. They were launched by the Titan-3C Trans-Stage and later Titan-34D Trans-Stage boosters with a total of at least one CHALET and 5 VORTEX successful launches total identified. The spacecraft were actually nothing more than USAF mission specific sophisticated earth orbit space based earth receiving stations operating over the entire emitted electro magnetic radio spectrum frequency range. The CHALET/VORTEX spacecraft introduced the second larger unfurling “wrap-rib” dish structures large white gold mesh covered deployable receiving dish antenna design of about 72 feet in diameter with a total spacecraft mass of about 4,000 pounds. CHALET/VORTEX’s first and only known CHALET launch was June 10, 1978 and the subsequent launches of the Vortex were on October 1, 1979, October 31, 1981, January 31, 1984, September 2, 1988 and its last launch was apparently on May 10, 1989.

The last of the VORTEX launches May 10, 1989 might have in fact been the USAF/RAF/NSA, ZIRCON spacecraft but there is no certainty on this issue . This would have been under the CANZUKUSA agreement treaty of 1948 ( Canada , Australia , New Zealand , United Kingdom , United States ) cooperation in the intelligence gathering or analysis of the USSR . The ARGUS series was passed on to the subsequent MAGNUM program series to follow

The CHALET/VORTEX series were designed to monitor and pick up from the ground and in flight electronic signals intelligence (ELINT), radio, communications intelligence (COMINT) and radar emitters emissions intelligence (RADINT) in addition to the primary missile test telemetry intelligence (TELINT) acquisitions capabilities all coming under the general SIGINT heading. They were fully dedicated mission operations that were highly successful in acquiring SIGINT through the larger mission general SIGINT “wrap-rib” white gold mesh covered reflector dishes. Its primary mission was radio, communications intelligence (COMINT).

The technology for these SIGINT spacecraft finally addressed the crying need for larger more sophisticated systems able to do multiple missions at the same time. The technology for these SIGINT spacecraft were slow in coming on line development wise but later proved out highly successfully once the technology was perfected. Like any new technology program it had its issues that slowed its initial progress.

Each gravity gradient stabilized spacecraft was about 128-185 feet in diameter with the dish attached to gimbals for steering from the command, communication, control and intelligence, power bus. CHALET-VORTEX’s dish did not cover the entire visible surface of the earth but covered more than its JUMPSEAT predecessor and thus the dishes were presumable set on gimbals to monitor specific points or objects of interest such as ballistic missile flight test telemetry. This would thus require several spacecraft to accomplish this monitoring task over the full range of the ICBM’s flight test.

It is presumed that each spacecraft rear bus carried two solar arrays and perhaps one or two down link communications dish. The launch shroud was 10.0 feet in outside diameter with a total length of 40 feet. Under the fairing shroud nose cap was the part of the spacecraft which housed the forward bus mounted sophisticated receiving feed horns with log periodic antennas collecting the earth based signals reflected off the larger “Wrap-Ribbed” supported white gold mesh covered SIGINT dish.

Above the feed horn’s apparatus housing circumstantially there was a new adjunct ballistic missile early warning sensor payload the GEM sensor system deployed on the CHALET-VORTEX, SIGINT satellite new variation of which were later deployed on previous and subsequent USAF, SIGINT satellite. This was used by the satellite not merely to back up early warning capabilities but to help track ballistic missile flights in progress. This practice of using sophisticated infrared sensors on the USAF payload to help track foreign ballistic missile test flights continues to this day with dramatic success. Examples of this are the RADIANT AGATE / COBRA BRSSS system deployed on JUMPSEAT, SIGINT satellite successor TRUMPET, SIGINT satellites would seem to indicate the early heritage of such adjunct payloads but there is no confirming USAF Space and Missile System Division histories on an otherwise silent highly classified adjunct payload deployment program. These examples are all USAF/NRO programs deployments only. It remains uncertain whether this spacecraft carried any early warning or sophisticated infrared sensors tracking sensors like those carried on the USAF based SIGINT satellites.

This spacecraft utilized the ten foot diameter by 14.99 foot long Trans-Stage to place the spacecraft on a geosynchronous transfer orbit that then became a elliptical near geosynchronous orbit once the Trans-Stage made its second burn and later the spacecraft bus housed orbital maneuvering engine was fired to placed it in that kind of a figure eight drifting orbital position. They were operated at an inclination that was at approximately 7.5-12 degrees with a perigee of 29,900-30,500 kilometers and an apogee of 41,490-42,050 kilometers with a spacecraft life of five to seven years. The CIA primarily utilized it for monitoring Soviet missile telemetry emissions. The USAF/NSA primarily utilized it for monitoring Soviet missile test flights operations telemetry traffic emissions.

The Trans-Stage rocket stage portion of the SIGINT packages carried the usual assortment of earth, horizon and solar sensors to orient the spacecraft but it did not remain attached to the spacecraft. The constellation of spacecraft was able to receive and send the data to several global ground stations via radio signal operated by NSA/ USAF personnel. The data was then mined at NSA headquarters for further analysis distribution to the USAF intelligence community. The spacecraft series cost rose from 250,000,000.00 to 300,000,000.00 each with a launch cost initially at 125,000,000.00 each.


 1. McDowell, Jonathan , U. S. Reconnaissance Satellites Programs, Part 2: Beyond Imaging, Quest, Vol. 4, No. 4.

2. Pike, Christopher Anson, “CANYON, RHYOLITE and AQUACADE,” Spaceflight, Vol. 37, November 1995 pp. 381-383.

Spysat (Vortex??) Mischarging Suit Blocked, thomasona@netcom.com (Allen Thomson), 1996/02/29.

Conceptual USAF Chalet Vortex SIGINT Series Spacecraft

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