 | Yantar-2K Cutaway
Credit - Dmitry Pieson
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Article Number: 11F624. Code Name: Feniks. Class: Surveillance. Type: Military. Destination: Surveillance Orbit. Nation: Russia. Agency: MOM. Manufacturer: Kozlov. Yantar was the Soviet Union's second series of photo reconnaissance satellites, succeeding the Zenit series in the primary film reconnaissance role. Yantars were identified in the West as 'Fourth Generation Photo Reconnaissance Satellite'. In comparison with the Zenit series, the Yantar was equipped with maneuvering engines to change the spacecraft's orbit, thereby providing more flexibility and surprise in photographing targets of interest. In common with the Zenit it was equipped with a large re-entry capsule which returned the camera and primary electronics for reuse. However it also had two small capsules for return of film before return of the main capsule. The design lifetime of Yantar was 30 days, as opposed to the 12 days of the Zenit. The SpK capsules would typically make interim film deliveries on the tenth and eighteenth days of flight. The Yantar project was first assigned to Yangel's KB Yuzhnoye in the period 1964-1967. The DS satellites of Yuzhnoye (Chief Constructor V M Kovtunenko) solved problems related to the Yantar series. But Yuzhnoye was too busy building ICBM's for the Soviet Strategic Rocket Forces. So Kozlov's Filial 1 of OKB-1 took up the project after a delay in 1967 to 1969.
The approval for development of Yantar was contained in an omnibus Central Committee decree in July 1967. An entire family of Yantar spacecraft was proposed by Kozlov's design bureau during the initial development; information on two film return models has been declassified. Yantar was initially derived from the Soyuz spacecraft, including systems developed for the cancelled Soyuz VI military model. During design and development this changed until it had very little in common with Soyuz.
Yantar development was plagued with several delays. The satellite was initially designed for launch by the Soyuz 11A511M launch vehicle, and Yantar-2K test-construction work began in 1970 . First equipment tests occurred on Zenit flights (by 1978 65 experimental Yantar instruments had been tested on Zenit). However the decision to standardize Soyuz launch vehicles to a common 11A511U version led to redesign and a delay in the first launch of the new spacecraft until after 1973. Even so neither the Kondor control system or the SpK film return capsules were ready when the launch vehicle was.
In February 1973 flight tests began of Yantar systems. The first attempted launch in May 1974 resulted in the launch vehicle being destroyed at third stage ignition. The first two successful Yantar flights used the Sokol control system from Zenit, in place of the VNIIEM-3M computer originally developed for the 11N6110. The second test flight resulted in successful return of the film. However a string of problems and failures then ensued. Tests of the production version began in September 1975. Six were flown, of which four completed their programs. The first fully equipped spacecraft did not fly until February 1976. The first full-configuration, fully successful flight finally came in April 1977. An acceptance test flight in October 1977 led to the Yantar-2K being accepted into Red Army service in May 1978.
The Yantar 2K featured double the duration and film capacity of earlier systems. This was combined with improved operational dissemination and use of information. Kozlov was the prime contractor, with the following major subcontractors:
- Gyroscope package: NII Priborostroenniy
- Radio altimeter: TsKB Geofizika
- Astro-tracker: NPO ELAS
Many original technical solutions were required to achieve optimal results and high reliability without sacrificing payload, since the Yantar-2K was mass-limited to launch by a Soyuz launch vehicle. The following technical problems had to be solved:
- Vertical arrangement of components
- Incorporation of the photographic apparatus Zhemchug-4
- Specialized data processors for use by autonomous landing capsules
- Control system, capable of:
- Autonomous operations of long duration able to conduct planned work even in the presence of highly maneuverable, non-co-operative satellites
- Acquire and analyze data on condition of satellite equipment operations
- Salyut-3M computer to acquire burst transmission command instructions and translate them into complex commands to on-board systems
- Automatic control of on-board systems, including pre-programmed failure modes taking into account built-in performance reserves
- Solar panel development, including use of the panels and other external devices to compensate for aerodynamic moments
- Equipment for high altitude navigation data
- 3 axis stabilization of optical axis on the target, including low altitude (140 km) pointing
- Development of completely new control methods - including ballistic programs, co-ordinate-time methods of control, landing capsule sub-programs.
The Yantar consisted of three modules, which formed a truncated cone with a half-angle of 12 degrees. From bottom to top these modules were:
AO - Agregatniy Otsek - Equipment Section. This section provided propulsion and electrical power to the spacecraft. It was descended from the Soyuz instrument section but by the completion of development had little in common with Soyuz systems. It consisted of:
KDU maneuvering system. The primary 11D430 engine burned storable N2O4/UDMH propellants pressure-fed at a 1.86 O:F ratio. Nominal propellant load was 680 kg but it could be varied according to mission from 300 to 900 kg. 3.65 kg of helium was stored in spherical tanks at 3.5-5 Mpa for pressure feed of the propellants. Dry mass of the entire system was 375 kg, with an average thrust of 300 kgf. Nominal burn time was 700 seconds, with 50 restarts and a specific impulse of 307 sec. The chamber pressure was 0.9 MPa.
Four URD orientation engine modules as follows:
Two URD-I modules with:
Two 11D431 engines with 0.6 kgf rated for 150,000 firings and 10,000 seconds of operation
One 11D446 engine with 5.3 kgf rated for 40,000 firings and 4,000 seconds of operation
One 11D428 engine of 11.2 kgf rated for 40,000 firings and 2,000 seconds of operation
Two URD-II modules with:
One 11D446 engine
One 11D428 engine
BR-91Ts-1 telemetry system
11M243 solar array actuators controlling two four-panel movable solar panels
Batteries
AO-Ya antenna
Grafit-Ya radio control system
Thermal radiators.
PO - Pribornniy Otsek - Instrument Section. This housed expendable electronics (the primary spacecraft computer was recovered with the Descent Section). Systems in the PO included:
Kondor attitude control system.
Data encryption and transmission system
Thermal control system
Commutator module
Electric supply system
BR-91Ts-1 telemetry system
Data processing system
Kvadrat orientation gyroscope system
Thermal radiators
OSA - Otsek Spetsialnoi Apparaturi - Special Equipment Section. This section was returned to Earth at the completion of the mission, returning the Zhemchug-4 camera and Salyut-3M primary computer for reuse. External to the conical re-entry capsule were two smaller spherical re-entry capsules for interim return of film during the mission, a toroidal instrument unit containing sensors that documented the altitude and position of each photo, and a movable cover to shield the camera from the sun when not in use. The systems included:
Zhemchug-4 photographic system with the primary film cassettes. This product of PO Krasnogorskiy Zavod of the Ministry of Defense Industry had been used in earlier models of the Zenit reconnaissance satellite but was repackaged for use in Yantar.
Photo system electronics
Film transport system for moving film into landing capsules
Kondor control system
Kalina synchronization unit
Program-timing unit
Salyut-3M spacecraft primary computer built by BTsVM
Thermal control system
Descent and landing system with:
8 x 11D445 orientation engines in 4 groups. Each engine had an average thrust of 9.4 kgf and was rated for 10,000 burns and 900 seconds of operation. Propellants were N2O4/UDMH, pressure fed by nitrogen stored at 35.0 MPa.
Gyroscopic guidance system
Radio altimeter
Parachute system
11D863 soft landing engine suspended in the parachute as had been developed for Voskhod. The 35 kg solid-fuel engine had four-nozzles, and delivered 10,000 kgf for 0.25 seconds, providing 8 m/sec of deceleration to provide a zero-velocity landing. Engine chamber pressure was 17 Mpa. The 0.28 m diameter engine had a length of 0.64m.
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Half-spherical heat shield
Camera system cover
Grafit-Ya system antenna
Infrared horizon sensors
Toroidal instrument module, containing systems that documented the height and location of the photograph:
Granit-Ya radio system
RVV vertical radio altimeter to document altitude of camera
AVU astro-photography system that photographed star fields at the time of exposure, allowing the precise position of the camera to be fixed
Mayak system VHF communications antenna
SpK - Spuskayemaya Kapsula - Descent Capsules. Two spherical SpK capsules were mounted on opposite sides of the OSA and provided interim return of film during the spacecraft's mission. Development of the SpK capsules began in 1968 at Kuibyshev, in parallel with the Block-K 11F76 film return capsules for the Almaz space station's Agat camera system. The capsules included:
Thermal control system
Telemetry systems
VHF beacon
Film containers
Parachute systems
Program timer
Pyrotechnic system for separation from the OSA
11D864 solid fuel deorbit engine. This 52 kg engine was 0.45 m long and had a diameter of 0.38 m. It had a chamber pressure of 8 Mpa and provided 600 kgf for 13 seconds.
Cold gas capsule spin-up system using the 8005D-0 gas reaction system. This stabilized the spacecraft after braking.
Western description: Fourth generation. Typical orbital profile: inclination 64.9, 67.1, or 70 degrees with an altitude of 170-340 km. Designed duration: 30 to 60 days. First flight: Cosmos 697. Last flight: Cosmos 1471. Transmission frequencies observed in West: 240.5 PCM-FM. Design Life: 30 days. Typical orbit: 166 x 350 km, 66.9 deg inclinaton. Length: 6.30 m (20.60 ft). Maximum Diameter: 2.70 m (8.80 ft). Mass: 6,600 kg (14,500 lb). Main Engine: 11D430. Associated Launch Vehicle: Soyuz 11A511U.
Yantar-2K Chronology - 1967 July 21 - US Project reassigned; R-36-O booster development approved; Yantar-2K and Zvevda 7K-VI approved. - Launch Vehicle: R-36-O, Tsyklon 2, Soyuz 11A511M.
Decree 715-240 'On the Creation of Space Systems for Naval Reconnaissance Comprising the US sat and the R-36-based booster -further work on the US naval reconnaissance satellite, approval of work on the Yantar-2K, and course of work on 7K-VI Zvezda'. An entire family of Yantar spacecraft was proposed by Kozlov’s design bureau during the initial development; information on two film return models has been declassified. Yantar was initially derived from the Soyuz spacecraft, including systems developed for the Soyuz VI military model. During design and development this changed until it had very little in common with Soyuz. Following numerous problems in the first flight tests of the Soyuz 7K-OK, Kozlov ordered a complete redesign of the 7K-VI manned military spacecraft. The new spacecraft, with a crew of two, would have a total mass of 6.6 tonnes and could operate for a month in orbit. The new design switched the positions of the Soyuz descent module and the orbital modules and was 300 kg too heavy for the standard 11A511 launch vehicle. Therefore Kozlov designed a new variant of the Soyuz launch vehicle, the 11A511M. The project was approved by the Central Committee of the Communist Party, with first flight to be in 1968 and operations to begin in 1969. The booster design, with unknown changes to the basic Soyuz, did not go into full production.
- 1974 December 13 - Cosmos 697 - Launch Site: Plesetsk. Launch Vehicle: Soyuz 11A511U. Mass: 6,600 kg (14,500 lb). Perigee: 174 km (108 mi). Apogee: 392 km (243 mi). Inclination: 62.80 deg. Period: 90.20 min. Duration: 12.00 days.
Yantar second generation reconnaissance spacecraft. After failure of the first Yantar-2K launch, a review board recommended modifications to the Soyuz U launch vehicle. This second Yantar still used the Sokol control system from the Zenit and lacked the SpK small film recovery capsules. As planned, after 12 days, the main descent capsule was successfully recovered with its film.
- 1975 September 5 - Cosmos 758 - Launch Site: Plesetsk. Launch Vehicle: Soyuz 11A511U. Mass: 6,600 kg (14,500 lb). Perigee: 174 km (108 mi). Apogee: 326 km (202 mi). Inclination: 67.10 deg. Period: 89.50 min. Duration: 1.00 days.
Third Yantar-2K second generation reconnaissance flight, the first with the new Kondor attitude control system. This system experienced problems and failed on the second day of flight. The spacecraft's destruct package was activated by ground command and the spacecraft was destroyed on 6 September 1975 in its second day of flight.
- 1976 February 20 - Cosmos 805 - Launch Site: Plesetsk. Launch Vehicle: Soyuz 11A511U. Mass: 6,600 kg (14,500 lb). Perigee: 171 km (106 mi). Apogee: 351 km (218 mi). Inclination: 67.10 deg. Period: 89.70 min. Duration: 20.00 days.
Fourth Yantar-2K second generation reconnaissance flight and the first with two SpK small film recovery capsules. First flight of the completely equipped satellite. The main reentry capsule and its film cargo were returned successfully. Both SpK capsules successfully separated from the Yantar in the course of the flight, but neither was recovered. The parachutes of the first did not deploy and the capsule crashed into the ground. The solid motor of the second capsule did not fire as programmed and the capsule did not deorbit at the expected time.
- 1977 April 26 - Cosmos 905 - Launch Site: Plesetsk. Launch Vehicle: Soyuz 11A511U. Mass: 6,600 kg (14,500 lb). Perigee: 170 km (100 mi). Apogee: 413 km (256 mi). Inclination: 67.10 deg. Period: 90.30 min. Duration: 30.00 days.
Sixth Yantar second generation reconnaissance test flight and first completely successful flight. Both small SpK film capsules successfully recovered during course of flight, as was the main OSA cabin with its camera, computer, and main film cannisters. First full duration Yantar flight.
- 1977 May 1 - Council of Chief Designers reconsiders Yantar Soviet reconnsat designs -
Flight trials of the Yantar-2K indicated the satellite was not capable of providing strategic warning of attack. The planned Yantar-6K series, in development since 1969, were overweight and behind schedule. A meeting of the Council of Chief Designers at TsSKB reviewed alternative approaches. It was decided that three variants of the Yantar-2K were to be developed, one of them the high resolution Yantar-4K.
Bibliography and Further Reading
- Isakowitz, Steven J,, International Reference to Space Launch Systems Second Edition, AIAA, Washington DC, 1991 (succeeded by 2000 edition). ISBN: 1563473534. Superseded by the later editions. More at amazon.com...
- 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.
- Siddiqi, Asif A, The Soviet Space Race With Apollo, University Press of Florida, 2003. ISBN: 0813026288. The definitive history of the Soviet manned space program in the 1960's to the early 1970's. Originally published as the the latter part of 'Challenge to Apollo' by NASA in 2000 as NASA SP-2000-4408. More at amazon.com...
- Melnik, T G, Voenno-Kosmicheskiy Siliy, Nauka, Moscow, 1997.. Two-volume official history of the (now defunct) Russin space forces.
- Grahn, Sven, Sven Grahn's Space History Pages, . Sven Grahn's occasional essays on specific topics of the Russian and Chinese space programs are outstanding. Accessed at: http://www.svengrahn.pp.se/.
- Sorokin, Vladislav, Novosti Kosmonavtiki, "'Yantarnaya istoriya'", 1997, Issue 17, page 57.
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