BYEMAN codenamed GAMBIT, the KH-7 (Air Force Program 206) was a reconnaissance satellite used by the United States from July 1963 to June 1967. Like the older CORONA system, it acquired imagery intelligence by taking photographs and returning the undeveloped film to earth. It achieved a typical ground-resolution of to . In 2002, all KH-7 satellite imagery, with the exception of some facilities in Israel, was declassified. Other details of the satellite program and construction remained classified until 2011.Flashlights in the dark, The Space Review
In its summary report following the conclusion of the program, the National Reconnaissance Office concluded that the GAMBIT program was considered highly successful in that it produced the first high-resolution satellite photography, 69.4% of the images having a resolution under ; its record of successful launches, orbits, and recoveries far surpassed the records of earlier systems; and it advanced the state of the art to the point where follow-on larger systems could be developed and flown successfully. The report also stated that Gambit had provided the intelligence community with the first high-resolution satellite photography of denied areas, the intelligence value of which was considered "extremely high". In particular, its overall success stood in sharp contrast to the two first-generation photoreconnaissance programs, Corona, which suffered far too many malfunctions to achieve any consistent success, and SAMOS, which was essentially a complete failure with all satellites either being lost in launch mishaps or returning no usable imagery.
GAMBIT emerged in 1962 as an alternative to the less-than-successful CORONA and the completely failed SAMOS, although CORONA was not cancelled and in fact continued operating alongside the newer program into the early 1970s. While CORONA used the Thor-Agena launch vehicle family, GAMBIT would be launched on Atlas-Agena, the booster used for SAMOS. After the improved KH-8 GAMBIT-3 satellite was developed during 1965, operations shifted to the larger Titan IIIB launch vehicle.
System configuration
Each GAMBIT-1 satellite was about long, wide, weighed about , and carried about of film.
A feasibility study for the Geodetic Orbital Photographic Satellite System reveals three subsystems for U.S. optical reconnaissance satellites in the 1960s: the Orbital (or Orbiting) Control Vehicle (OCV), the Data Collection Module (DCM), and the Recovery Section (RS). For the KH-7, the DCM is also called the Camera Optics Module (COM), and is integrated in the OCV, which has a length of and a diameter of .
Camera Optics Module The Camera Optics Module of KH-7 consists of three cameras: a single strip camera, a stellar camera, and an index camera.
In the strip camera the ground image is reflected by a steerable flat mirror to a diameter stationary concave primary mirror. The primary mirror reflects the light through an opening in the flat mirror and through a Ross corrector. It took images of a 6.3° wide ground swath by exposing a wide moving portion of film through a small slit aperture. The initial ground resolution of the satellite was , but improved to by 1966. Each satellite weighed about , and returned a single film bucket per mission. The camera and film transport system were manufactured by Eastman Kodak Company.
The index camera is a copy of cameras systems previously used in the KH-4 and KH-6 satellites, and takes exposures of Earth in direction of the vehicle roll position for attitude determination. The stellar camera takes images of star fields with a reseau grid being superimposed on the image plane. The S/I camera was provided by Itek, and horizon sensors were provided by Barnes Engineering Co.
Orbital Control Vehicle and Recovery Vehicle
The primary contractor for the Orbital Control Vehicle and the Recovery Vehicle was General Electric. Films were to be retrieved mid-air by a C-130 Hercules specially outfitted for that purpose.
Mission All KH-7 satellites were launched from Point Arguello, which became part of Vandenberg Air Force Base in July 1964. KH-7 satellites flew 38 missions, numbered 4001-4038, of which 34 returned film, and of these, 30 returned usable imagery. Mission duration was 1 to 8 days. KH-7 satellites logged a total of almost 170 operational days in orbit.
Functionality
A high-resolution instrument, the KH-7 took detailed pictures of "hot spots" and most of its photographs are of Chinese and Soviet nuclear and missile installations, with smaller amounts of coverage of cities and harbors.NARA ARC database description of "Keyhole-7 (KH-7) Satellite Imagery, 07/01/1963 - 06/30/1967", accession number NN3-263-02-011 Most of the imagery from this camera, amounting to 19,000 images, was declassified in 2002 as a result of Executive order 12951, the same order which declassified CORONA, and copies of the films were transferred to the U.S. Geological Survey's Earth Resources Observation Systems office.edc.usgs.gov Approximately 100 frames covering the state of Israel remain classified.
In early 1964, the CIA toyed with the idea of using GAMBIT to photograph military installations in Cuba, but this was dismissed as unworkable as the satellites were primarily designed with higher-latitude Soviet territory in mind and because it would mean wasting an entire satellite on the Latin America-Caribbean area which had little else of interest to U.S. intelligence services. It was decided that U-2 spyplane flights were adequate to provide coverage of Cuban activity.
ELINT subsatellite Mission 4009 included an ELINT P-11 subsatellite for radar monitoring, which was launched into a higher orbit.
List of launches
Name Mission No. Launch Date Alt. Name NSSDC ID No. Launch Vehicle Perigee (km) Apogee (km) Inclination (deg) KH7-1 4001 1963-07-12 OPS-1467 1963-028A Atlas-Agena D 164 164 95.4 KH7-2 4002 1963-09-06 OPS-1947 1963-036A Atlas Agena D 168 263 94.4 KH7-3 4003 1963-10-25 OPS-2196 1963-041A Atlas Agena D 144 332 99.1 KH7-4 4004 1963-12-18 OPS-2372 1963-051A Atlas Agena D 122 266 97.9 KH7-5 4005 1964-02-25 OPS-2423 1964-009A Atlas Agena D 173 190 95.7 KH7-6 4006 1964-03-11 OPS-3435 1964-012A Atlas Agena D 163 203 95.8 KH7-7 4007 1964-04-23 OPS-3743 1964-020A Atlas Agena D 150 366 103.6 KH7-8 4008 1964-05-19 OPS-3592 1964-024A Atlas Agena D 141 380 101.1 KH7-9 4009 1964-07-06 OPS-3684 1964-036A Atlas Agena D 121 346 92.9 KH7-10 4010 1964-08-14 OPS-3802 1964-045A SLV-3 Agena D 149 307 95.5 KH7-11 4011 1964-09-23 OPS-4262 1964-058A SLV-3 Agena D 145 303 92.9 KH7-12 4012 1964-10-08 OPS-4036 1964-F11 SLV-3 Agena D --- --- --- KH7-13 4013 1964-10-23 OPS-4384 1964-068A Atlas Agena D 139 271 88.6 KH7-14 4014 1964-12-04 OPS-4439 1964-079A SLV-3 Agena D 158 357 97 KH7-15 4015 1965-01-23 OPS-4703 1965-005A SLV-3 Agena D 146 291 102.5 KH7-16 4016 1965-03-12 OPS-4920 1965-019A SLV-3 Agena D 93 155 KH7-17 4017 1965-04-28 OPS-4983 1965-031A SLV-3 Agena D 180 259 95.7 KH7-18 4018 1965-05-27 OPS-5236 1965-041A SLV-3 Agena D 149 267 95.8 KH7-19 4019 1965-06-25 OPS-5501 1965-050B SLV-3 Agena D 151 283 107.6 KH7-20 4020 1965-07-12 OPS-5810 1965-F07 SLV-3 Agena D --- --- --- KH7-21 4021 1965-08-03 OPS-5698 1965-062A SLV-3 Agena D 149 307 107.5 KH7-22 4022 1965-09-30 OPS-7208 1965-076A SLV-3 Agena D 98 164 95.6 KH7-23 4023 1965-11-08 OPS-6232 1965-090B SLV-3 Agena D 145 277 93.9 KH7-24 4024 1966-01-19 OPS-7253 1966-002A SLV-3 Agena D 150 269 93.9 KH7-25 4025 1966-02-15 OPS-1184 1966-012A SLV-3 Agena D 148 293 96.5 KH7-26 4026 1966-03-18 OPS-0879 1966-022A SLV-3 Agena D 162 208 101 KH7-27 4027 1966-04-19 OPS-0910 1966-032A SLV-3 Agena D 139 312 116.9 KH7-28 4028 1966-05-14 OPS-1950 1966-039A SLV-3 Agena D 133 358 110.5 KH7-29 4029 1966-06-03 OPS-1577 1966-048A SLV-3 Agena D 143 288 86.9 KH7-30 4030 1966-07-12 OPS-1850 1966-062A SLV-3 Agena D 137 236 95.5 KH7-31 4031 1966-08-16 OPS-1832 1966-074A SLV-3 Agena D 146 358 93.3 KH7-32 4032 1966-09-16 OPS-1686 1966-083A SLV-3 Agena D 148 333 93.9 KH7-33 4033 1966-10-12 OPS-2055 1966-090A SLV-3 Agena D 155 287 91 KH7-34 4034 1966-11-02 OPS-2070 1966-098A SLV-3 Agena D 159 305 91 KH7-35 4035 1966-12-05 OPS-1890 1966-109A SLV-3 Agena D 137 388 104.6 KH7-36 4036 1967-02-02 OPS-4399 1967-007A SLV-3 Agena D 136 357 102.4 KH7-37 4037 1967-05-22 OPS-4321 1967-050A SLV-3 Agena D 135 293 91.5 KH7-38 4038 1967-06-04 OPS-4360 1967-055A SLV-3 Agena D 149 456 104.8 (NSSDC ID Numbers: See COSPAR)
History
Section source: Space Review
GAMBIT marked the first use of next-generation launch vehicle systems as Convair and Lockheed, the builders of the Atlas-Agena booster, began introducing improved, standardized launchers to replace the multitude of customized variants used up to 1963, which caused endless mix ups, poor reliability, and mission failures. This followed a recommendation by the Lewis Spaceflight Center in Cleveland, Ohio that Atlas and Agena switch to one standard configuration for both NASA and Air Force launches, with uniform testing and checkout procedures, as well as improved materials and fabrication processes for the various hardware components in the boosters. The Agena D, a standardized Agena B, arrived first, with the uprated Atlas SLV-3 taking another year to fly. The first eight GAMBIT flown still used custom-modified Atlas D ICBM cores, with GAMBIT 4010 in August 1964 being the first use of the SLV-3. Afterwards, all GAMBIT used SLV-3s aside from 4013, which used the last old-style Atlas remaining in the inventory.
In early 1963, the GAMBIT program began with failures. On 11 May 1963, the first GAMBIT satellite sat atop Atlas-Agena 190D on SLC-4W at Vandenberg Air Force Base awaiting launch. An air bubble formed while loading LOX into the booster and as soon as propellant filling was stopped, the bubble damaged the fill/drain valve. This quickly caused both the LOX and helium pressure gas to escape from the tank, depressurizing the Atlas's balloon skin and causing the entire launch vehicle to crumple to the ground. The RP-1 tank ruptured and spilled its contents onto the pad. There was no fire or explosion, but the Agena sustained minor damage and the satellite a considerable amount as the cameras were crushed in by impact with the ground and had their lenses destroyed. The pad itself was undamaged except for a steel beam cracked by exposure to the super-chilled LOX, which was repaired in two days. Fortunately, the satellite on the booster was not the same one planned for the actual launch and the payload shroud had also remained in one piece, preventing any unauthorized parties from seeing the GAMBIT. Secrecy surrounding the program was strict and knowledge of GAMBIT limited only to those directly involved in the program. While the early CORONA and SAMOS flights had been merely billed to the public as scientific missions, it became increasingly difficult to explain why they failed to return any scientific data. In late 1961, President John F. Kennedy ordered a veil of secrecy placed around the photoreconnaissance program and by GAMBIT's debut in 1963, DoD announcements described no details other than the launching of a "classified payload".
The Agena was sent back to Lockheed for repairs and a different Atlas (vehicle 201D) was used, and the first successful GAMBIT mission was launched on 12 July 1963. The launch vehicle performed perfectly and inserted GAMBIT into polar orbit with a altitude. The Air Force designated this mission number 4001.