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| Buran docks to Mir - As it was supposed to be - Buran docking with Mir space station. 29,143 bytes. 298 x 377 pixels. |
The Energia-Buran Reusable Space System (MKS) had its origins in NPO Energia studies of 1974 to 1975 for a 'Space Rocket Complex Program'. In 1974 the N1-L3 heavy lunar launch vehicle project was cancelled and Glushko was appointed chief designer of the new NPO Energia enterprise, replacing Mishin as the head of the former OKB-1. At the same time in the United States development work was underway on the space shuttle. The US Defence Department planned to use the shuttle for a range of military missions. The Soviet military, seeking strategic parity, wished development in the Soviet Union of a reusable manned spacecraft with analogous tactical-technical characteristics. The success of Apollo and the failure of the N1-L3 program pointed to serious deficiencies in the technology base of the Soviet Union. The time-honoured Soviet method of rectifying such situations was to copy the foreign technology.
To reduce development cost and risk, NASA and USAF shuttle trade studies had settled on a partially reusable design. While the solid propellant booster rockets were recovered, the cryogenic main propellant tank of the shuttle core was expendable. The main engines and guidance system were recovered with the orbiter.
The American shuttle design was studied intensively by Russian rocket scientists, but important aspects of it were rejected based on Soviet engineering analysis and technology:
The Soviet Union at this point had no experience in production of large solid rocket motors, especially segmented solid rocket motors of the type used on the shuttle. Glushko favoured a launch vehicle with parallel liquid propellant boosters. These would use a 700 tonne thrust four-chamber Lox/Kerosene engine already under development.
The high chamber pressure, closed-cycle, reusable 230 tonne thrust Lox/LH2 main engine being developed for the shuttle was well outside engineering experience in the Soviet Union. No engine using these cryogenic propellants had ever been used in Russian rockets, and the largest such engine under development was the 40 tonne thrust 11D57. Glushko believed that while a Soviet cryogenic engine of 200 tonnes thrust could be developed in the required time, to develop a reusable engine would be impossible due to limited experience with the propellants.
This conclusion led to other important design decisions. If only expendable engines were to be used, there was no need to house them in the re-entry vehicle for recovery. This meant that the orbiter itself could be moved from the lateral mounting of the space shuttle to an on-axis position at the top of the rocket core. The result was the Vulkan - a classic Soviet launch vehicle design: booster stages arranged around a core vehicle, with the payload mounted on top. The elimination of the lateral loads resulted in a lighter booster, and one that was much more flexible. The vehicle could be customised for a wide range of payloads by the use of from two to eight booster stages around a core equipped with from one to four modular main engines. Either a payload container for heavy payloads (Glushko's LEK lunar base) or the military's required spaceplane could be placed on the nose as the payload.
As far as the manned orbital vehicle itself, three different primary configurations were studied extensively, as well as a range of more radical proposals. The obvious choice was a straight aerodynamic copy of the US shuttle. The shuttle's form had been selected by NASA and the US Air Force only after painstaking iterative analysis of over 64 alternate configurations from 1968 to 1972. It would obviously benefit the Soviet engineers to take advantage of this tremendous amount of work.
However the NPO Energia specialists who had developed the Soyuz capsule disapproved of the winged US shuttle design. They knew from the extensive aerodynamic studies undertaken to develop Soyuz that there were large weight penalties and thermal control problems in any winged design. Their studies indicated that a lifting body shape capable of high angles of bank at hypersonic speed could nearly match winged designs in cross range. Therefore their preferred 1974 design was an unwinged spacecraft, consisting of a crew cabin in the forward conical section, a cylindrical payload section, and a final cylindrical section with the engines for manoeuvring in orbit. This unwinged MTKVA would glide to the landing zone at low subsonic speed. The final landing manoeuvre would use parachutes for initial braking, followed by a soft vertical landing on skid gear using retrorockets. After a great deal of detailed analysis the definitive MTKVA design proposed in May 1976 had a refined aerodynamic shape with a rounded triangular cross section. The 200 tonne vehicle had over twice the shuttle's mass and nearly three times the shuttle's payload.
 | Buran configurations - Configurations of Buran launch vehicle tested during development. Credit: © Mark Wade. 10,121 bytes. 288 x 137 pixels. |
The government decree 132-51 authorising development of the Energia-Buran system was issued on 12 February 1976 with the title 'On development of an MKS (reusable space system) consisting of rocket stages, orbiter aircraft, inter-orbital tug, guidance systems, launch and landing facilities, assembly and repair facilities, and other associated facilities, with the objective of placing in a 200 km Northeast orbit a payload of 30 tonnes and returning a payload of 20 tonnes'. The Ministry of Defence was named the Program Manager, with NPO Energia as the prime contractor. The official military specification (TTZ) was issued at the same time with the code name Buran. A declaration of the Presidium on 18 December 1976 directed co-operation between all concerned user, research, and factory organisations in realising the project. Chief Constructor within NPO Energia was I N Sadovskiy. Chief Designer for the launch vehicle was Y P Kolyako and for the orbiter P V Tsybin. NPO Yuzhnoye in the Ukraine would build the booster rockets. While NPO Energia would build the booster engines, the core Lox/LH2 engines would be built by Kosberg. Chelomei and MiG were to continue, at a modest level, design and test of their LKS and Spiral smaller spaceplanes as backups.
 | Buran configurations - Aerodynamic configurations of Buran tested during development. Credit: © Mark Wade. 20,255 bytes. 487 x 253 pixels. |
 | Buran artilce - Buran handling article deteriorates in safing area. Credit: © Mark Wade. 27,419 bytes. 458 x 369 pixels. |
The MKS draft project was completed on 12 December 1976. The military assigned the system the index number 1K11K25 and the launch vehicle the article number 11K25. The draft project was reviewed by the expert commission in July 1977, leading to a government decree 1006-323 of 21 November 1977 setting out the development plan. The technical project was completed in May 1978. The flight test plan at the beginning of the project foresaw first launch of the booster in 1983, with the payload being an unmanned OK-ML-1 mock-up of the orbiter. This would not have a heat shield and remain attached to the booster. A second mock-up, OK-ML-2, would be used on the second launch, but be separated from the vehicle after burnout. However it would also be without heat shield, and be expended. The first flight Buran was to fly unpiloted in 1984. Manned flights were to be routine by the 1987 seventieth anniversary of the Soviet Union.
The approved launch vehicle layout consisted of the core Block Ts stage, surrounded by 4 Block A liquid propellant boosters and the Buran orbiter or a payload canister. During assembly, transport, and on the pad these were attached to a Block Ya launch services module, which provided all pneumatic, electrical, hydraulic, and other services to the vehicle prior to launch.
 | Buran configurations - Configurations of Buran launch vehicle tested during development. Credit: © Mark Wade. 35,059 bytes. 570 x 274 pixels. |
Propellant selection was a big controversy. Use of solid propellants in the booster stages, as used in the space shuttle, was considered again. But Soviet production of solid fuel motors had been limited to small unitary motors for ICBM's and SLBM's. There was no technological base for production of segmented solid fuel motors, and transport of the motor sections also presented problems. The final decision was to use the familiar Lox/Kerosene liquid propellants for the boosters. In the 1960's Glushko had favoured use of toxic but storable chemical propellants in launch vehicles and had fought bitterly against Korolev over the issue. It is surprising that he now accepted use of Lox/Kerosene. But Korolev was dead, and the N1 a failure. Glushko's position had been vindicated, perhaps he now had to agree objectively that use of the expensive and toxic propellants in a launch vehicle of this size was not rational.
Another factor may have been that the propellants of the core were going to be cryogenic anyway. Lox/Kerosene propellants for the core were considered, but a primary objective of the project was to seek technological parity with the United States by exploiting technologies developed there. Chief among these in the field of liquid fuel rocketry was the use of Lox/LH2 propellants. Therefore the engines of the core were based on the Space Shuttle Main Engine (SSME) of the USA, with the same thrust rating and specific impulse specifications.
 | Buran payload car - Rail transport car for Buran payloads. Credit: © Mark Wade. 31,375 bytes. 548 x 275 pixels. |
Drawing on this blend of mature American technology and Soviet innovation, the RD-0120 had a relatively trouble-free development program. The final engine represented for the Soviet Union new technical solutions in engine reliability, control, throttleability, and performance. These were the first fully throttleable Soviet engines, and their first production Lox/LH2 engines.
By contrast the RD-170 engine for the booster stage was a purely Soviet design and experienced a slow and difficult development program. These were exactly the kind of closed-cycle liquid oxygen/kerosene engines that Glushko had opposed developing in the 1960's. In addition the TTZ required that they be reusable for ten missions. Glushko fell back on his old solution when being unable to handle combustion stability problems: an engine unit consisting of four chambers fed by common turbopumps. Providing adequate wall cooling for the high temperature / high pressure combustion chambers seemed at times insoluble. One problem followed another and finally the RD-170 became the pacing item, with rocket stages completed but lacking engines. As costs reached the project ceiling, Glushko and Minister Afanasyev had to escalate the fight to the highest levels of the Soviet leadership. But Glushko defended his people, retained his job, and the problems were eventually solved.
 | Anechoic chamber - The anechoic chamber where Buran was given antenna tests. It also shielded certain activities from US ELINT spacecraft. Credit: © Mark Wade. 33,806 bytes. 495 x 332 pixels. |
In 1979 the EUK13 dimensional model of the launch vehicle was delivered to Baikonur for handling demonstrations and production of tooling. Continued development problems with the booster rockets led to a management shake-up at Yuzhnoye in January 1982. By this time the project was several years behind schedule. The originally planned first flight in 1983 was obviously unattainable. Also in 1982 the 3M-T transport aircraft was completed and began delivery of central block propellant tanks and structural elements for construction of a realistic mock-up of the booster. The 3M-T was a heavily modified M-4 bomber, and was limited to 50 tonnes loads carried on the top of the fuselage. By December 1982 the 4M Energia mock-up was completed, leading to dynamic/vertical/load tests in May-October 1983. The 4M was then returned to the shop for fitting of complete functional propellant systems.
The OK-KS Buran systems test stand was built at NPO Energia to conduct tests not possible on other stands. These included electrical layout, pneumo-hydraulic tests in abort conditions, EMI tests, failure mode response, telemetry, interface with the launch vehicle, software systems test. The test stand was completed in August 1983 and the test series was completed in March 1984. 77% of the tests of the OK were automated, compared with only 5% for the Soyuz-TM.
The 50 payload limitation of the 3M-T transport meant that the Buran orbiters had to be delivered in a severely incomplete and stripped-down condition to the cosmodrome. They were delivered without orbital systems, engine section, crew cabin, vertical stabiliser, landing gear, and with only 70% of the heat shield tiles. This meant that complex final assembly operations had to conducted at the MIK-OK at Baikonur. The OK-ML-1 orbiter mock-up arrived atop the 3M-T at Baikonur in December 1983 (This action seems to have been in the fine Soviet tradition of individual enterprises proving they have met the plan, even if the method of doing it is useless. OK-ML-1 was to have been used in the first launch of the Energia, by the end of 1983. By delivering it to Baikonur by December 31, the spacecraft builders could claim, "well, we met OUR part of the plan..."). OK-ML-1 was used for handling and pad compatibility tests. It was followed by the OK-MT in August 1984. This functional mock-up was used for systems integration tests, and was to be expended on the second test flight.
 | Buran prep area - Buran final preparation area before integration with Energia launch vehicle. Credit: © Mark Wade. 40,252 bytes. 504 x 332 pixels. |
The OK-GLI Buran analogue flight vehicle, for horizontal subsonic approach and landing tests, was delivered to Zhukovskiy test flight centre near Moscow, followed by its first flight with Cosmonaut Igor Volk at the controls on 10 November 1985. Two flying labs, based on Tu-154 transports, were used to prior to this to duplicate anticipated Buran handling and test systems software. They conducted 140 flights before Buran's first flight, including 69 automatic landings at Zhukovskiy and at the Jubilee airfield at Baikonur.
In December 1985 the wings of the first flight OK arrived at Baikonur. This was followed by what was to be the first 20 second Energia main engine firing test. This was terminated at 2.58 seconds when the automatic control system detected a slow spool up of an engine turbine. In a the first attempt at a full-duration test helium leaks contaminated electro-hydraulic systems, leading to a situation where the tanks could not be drained. An engineering brigade had to work on the fuelled booster for 55 minutes, attach another helium tank, which led to successful de-fuelling of the vehicle. The second engine test was a complete success, the engine running for 390 seconds. This test required the entire city of Leninsk to be without water for ten days in order to accumulate enough water for the UKSS cooling system.
By January 1986 it was clear that the project, now three years behind schedule, had no prospect of completion due to problems in obtaining deliveries of equipment for Buran, numerous problems in assembling the orbiters and lack of manpower at Baikonur, and a general loss of management focus. Minister O D Bakhnov called large group of industry leaders to the cosmodrome to review measures to concentrate and accelerate the remaining work. Three 'Tiger Teams' were set up. The first, led by Semenov, was to finish the flight Buran orbiter and associated facilities in time for a third quarter 1987 launch. The second, led by B I Gubanov, was to finish the Energia launch vehicle and fly it, without the Buran mock-ups if necessary, at the earliest possible date. The third group, led by S S Banin, was to complete the assembly and launch facilities.
 | 37KB - 37KB instrumentation payload carried aboard first Buran flight. This module is closely related to the Kvant module on Mir and a similar x-ray astronomy module that Buran would have flown to Mir if it had not been cancelled. Credit: © Mark Wade. 62,683 bytes. 574 x 394 pixels. |
The first Buran payload, 37KB module s/n 37070, arrived in Baikonur in February 1986. The 37KB modules, similar to the Kvant module of the Mir space station, were to be standard on the early Buran flights. 37KB-37070 itself primarily contained instrumentation to measure the performance of the orbiter and its structure on its first flight.
As with the American shuttle, tile installation was a big problem. However once adequate manpower was provided the work was completed in three months. Electrical tests of the Buran flight vehicle began in May 1986. Tests of the orbiter's ODU engine unit uncovered an apparent defect in gaseous oxygen valves of the reaction control system. Although it threatened to delay flight of the Buran, it was eventually discovered to be a software problem and remedied within days.
In August-September 1986 further UKSS tests of Energia were conducted in preparation of a test launch without Buran. These were conducted using a dummy payload and solid rocket motors to simulate loads from the booster rockets. Following this vehicle 6SL was selected for the first actual launch. The launch vehicle used by itself without Buran was named Energia by Glushko only just before the launch. Energia was to deliver the military Skif-DM Polyus battle station into orbit. This was to be followed by ten flights of Energia-Buran, only the first of which was to be unpiloted.
Due to delays in completion of the enormous static test facility at Baikonur, which could test the entire Energia vehicle stack, it was decided to launch the vehicle without the verification the tests would provide. The launch of 6SL was planned for 11 May 1987 at 21:30 Moscow time. It was delayed five hours when a leak was detected in the Block 3A electrical distribution section, then by another hour due to a fault LH2 thermostat. The launch vehicle performed successfully, but the payload failed to inject itself into orbit due to a guidance system failure.
 | Buran wind tunnel - Buran wind tunnel model for testing strapon separation. Credit: © Mark Wade. 10,768 bytes. 197 x 206 pixels. |
While this debate was underway a collective letter was sent to the Soviet government by workers on the project, including the cosmonauts Volk and Leonov. This letter argued that the first flight should be piloted, as was the American space shuttle. In order to resolve the issue, a special commission was appointed to study the alternatives. The commission decided in favour of the two orbit automated flight.
Buran was first moved to the launch pad on 23 October 1988. The launch commission met on 26 October 1988 and set 29 October 06:23 Moscow time for the first flight of the first Buran orbiter (Flight 1K1). 51 seconds before the launch, when control of the countdown switched to automated systems, a software problem led the computer program to abort the lift-off. The problem was found to be due to late separation of a gyro update umbilical. The software problem was rectified and the next attempt was set for 15 November at 06:00 (03:00 GMT). Came the morning, the weather was snow flurries with 20 m/s winds. Launch abort criteria were 15 m/s. The launch director decided to press ahead anyway. After 12 years of development everything went perfectly. Buran, with a mass of 79.4 tonnes, separated from the Block Ts core and entered a temporary orbit with a perigee of -11.2 km and apogee of 154.2 km. At apogee Burn executed a 66.6 m/s manoeuvre and entered a 251 km x 263 km orbit of the earth. In the payload bay was the 7150 kg module 37KB s/n 37071. 140 minutes into the flight retrofire was accomplished with a total delta-v of 175 m/s. 206 minutes after launch, accompanied by Igor Volk in a MiG-25 chase plane, Buran touched down at 260 km/hr in a 17 m/s crosswind at the Jubilee runway, with a 1620 m landing rollout. The completely automatic launch, orbital manoeuvre, deorbit, and precision landing of an airliner-sized spaceplane on its very first flight was an unprecedented accomplishment of which the Soviets were justifiably proud. It completely vindicated the years of exhaustive ground and flight test that had debugged the systems before they flew.
 | Buran static article - Converted Buran static article now a ride in Gorky Park Credit: © Mark Wade. 38,956 bytes. 497 x 403 pixels. |
Planned Buran Flight Program
What was Buran for? Various Russian engineers have stated that there were no payloads identified for it, that it was an insane copy of a system the Americans should not have developed either. But it should be recalled that the project was run by the Ministry of Defence. At the time of the project go-ahead, the Soviets knew of American work on x-ray lasers. These nuclear bomb-pumped devices would have been barely larger than a desk, but were to be capable of destroying dozens of ICBM�s simultaneously. Most remarkably, such was the power of these weapons, it was thought possible to fry the Soviet ICBM�s right in their silos before they were ever launched. A single shuttle payload bay could contain enough of these weapons to destroy the entire Soviet retaliatory force. The US shuttle design was driven primarily by a US Air Force requirement that the shuttle enter polar orbit from Vandenberg Air Force base, complete one orbit of the earth, and have enough cross-range to recover back at Vandenberg. Perhaps this was merely to meet Abort-Once-Around criteria. But the Soviet military could only interpret the entire shuttle system as a means for the United States to conduct a totally effective first strike against Soviet nuclear forces.
Later it was found that the x-ray laser was perhaps not feasible after all, and the effort to build this weapon drifted into Reagan�s bewildering Star Wars panoply of chemical lasers, particle beams, smart rocks and brilliant pebbles. But to match this program the Soviets would need a massive space infrastructure as well. Buran would be used to construct and maintain the Mir-2 and KS military space stations. These would be service centres for a range of combat spacecraft. Buran would deliver and service, within its cargo bay, Almaz-derived BKA spacecraft equipped with chemical lasers or rocket interceptors. A wingless version of the Buran would form the basis of BM military modules. These would be immense manoeuvring hangars, the cargo bay filled with rocket interceptors. Launched by Energia, they would automatically dock with the KS space station and normally remain there for servicing and maintenance. In times of crisis or attack, they would separate from the station, manoeuvre to varying orbits, and dispense their deadly anti-satellite/anti-missile payloads.
 | Buran subscale model - Buran subscale test article. Credit: © Mark Wade. 26,215 bytes. 417 x 276 pixels. |
For civilian applications there were a great number of proposed applications, although few of them had prospects for funding.. Energia high-level nuclear waste out of the biosphere into solar orbit. It would orbit, and Buran would maintain, constellations of satellites to fire lasers into the stratosphere to renew the Earth�s ozone layer; satellites equipped with mirror to illuminate northern cities in winter; heavy geosynchronous satellites linked to form an integrated global information system; orbital debris tenders that would collect dead satellites and spent stages and deorbit them; geosynchronous environmental and strategic treaty compliance platforms; radio telescopes to observe space and the earth.
More modestly, it was also planned to fly Buran on civilian space research missions similar to those conducted by the American shuttle. These would use equipment aboard the 37KB modules to conduct biological and materials experiments that required micro-gravity or high vacuum. For such experiments Buran�s fuel cells provided a generous 60 kW of power maximum, which could not be matched aboard solar-powered space stations. Buran�s orbital micro-gravity environment of 1/10,000 G - 1/100,000 G was adequate for many zero-G experiments. For biological research, the Rekomb-2, Ruchey-2, and Potok devices were built. Materials research would be conducted by the Krater-AG and Malakhit devices.
The flight test program at the time the program was cancelled was quite conservative in comparison with some of the grand plans. Originally three flight orbiters were to be built, but this was increased to 5 in 1983. Structurally the first three orbiters were essentially completed, while the extra two remained unbuilt except for the engine units. The final Buran test flight plan at the beginning of 1989 was as follows:
 | Buran in storage - Buran in storage at Baikonur. Credit: © Mark Wade. 34,028 bytes. 497 x 323 pixels. |
Flight 2 (2K1) - fourth quarter 1991 - first flight of second orbiter, one to two days unmanned, with 37KB s/n 37071. The payload bay doors would be opened for the first time. The payload module would already include automated equipment for materials and biological science research.
Flight 3 (2K2) - first or second quarter 1992 - second orbiter, seven to eight day unmanned flight with payload 37KB s/n 37271. The orbiter would open the payload bay doors, operate the manipulator arm, dock with Mir, and return to earth.
Flight 4 (1K2) - 1993 - unmanned, second flight of first orbiter, 15-20 days with 37KB s/n 37270
Flight 5 (3K1) - 1994 or 1995 - first flight of third orbiter. First manned flight; the third orbiter was to be the first outfitted with life support systems and ejection seats. Two cosmonauts would deliver the 37KBI module to Mir, using the Buran manipulator arm to dock it to the station's Kristal module.
Development of the launch vehicle cost 1.3 billion roubles, with an estimated total economic effect of 6 billion roubles. Total cost of the Energia-Buran project was put at 14.5 billion roubles, although it was said at the time it was cancelled total cost was 20 billion roubles. Buran involved the work of 1206 subcontractors and 100 government ministries. The cost of Buran - a significant part of the effort to maintain strategic and technical parity with the United States - contributed to the collapse of the Soviet system and thus the demise of Buran itself. Today the flight orbiters sit in their assembly halls in Baikonur, covered in dust. The Energia core stages are still in their jigs in the MIK assembly hall, immense exhibits. The booster stages are in forlorn rows, their engines stripped for more lucrative use on Zenit and Atlas boosters launched by American companies. The orbiter mock-up stands in the safing area, quietly crumbling in the desert. The apartment buildings are vacant. The rest is silence.
 | Buran safing area - Buran safing area with LC 1 launch pad in the distance. Credit: © Mark Wade. 23,192 bytes. 540 x 201 pixels. |
Although of the same aerodynamic shape and size as the shuttle, Buran differs in detail. The following table compares the two spaceplanes:
| Shuttle | Buran | |||
| Mass Breakdown (kg): | ||||
| Total Structure / Landing Systems | 46,600 | 42,000 | ||
| Functional Systems and Propulsion | 37,200 | 33,000 | ||
| SSME | 14,200 | |||
| Maximum Payload | 25,000 | 30,000 | ||
| Total | 123,000 | 105,000 | ||
| Dimensions (m): | ||||
| Length | 37.25 | 36.37 | ||
| Wingspan | 23.80 | 23.92 | ||
| Height on Gear | 17.25 | 16.35 | ||
| Payload bay length | 18.29 | 18.55 | ||
| Payload bay diameter | 4.57 | 4.65 | ||
| Wing glove sweep | 81 deg | 78 deg | ||
| Wing sweep | 45 deg | 45 deg | ||
| ||||
| Propulsion | ||||
| Total orbital manoeuvring engine thrust | 5,440 kgf | 17,600 kgf | ||
| Orbital Manoeuvring Engine Specific Impulse | 313 sec | 362 sec | ||
| Total Manoeuvring Impulse | 5 kgf-sec | 5 kgf-sec | ||
| Total Reaction Control System Thrust | 15,078 kgf | 14,866 kgf | ||
| Average RCS Specific Impulse | 289 sec | 275-295 sec | ||
| Normal Maximum Propellant Load | 14,100 kg | 14,500 kg | ||
| Schedule: | ||||
| Go-ahead | Jul 26 1972 | Feb 12 1976 | ||
| Years after go-ahead: | ||||
| Delivery to launch complex | 6.6 | 9.3 | ||
| Flight Readiness Firing | 8.5 | 10.3 | ||
| First launch vehicle flight | 8.7 | 11.2 | ||
| First orbiter flight | 8.7 | 12.7 | ||
 | Buran subscale model - Buran subscale dynamic test article in test stand. Credit: © Mark Wade. 20,205 bytes. 212 x 394 pixels. |
The Buran orbiter was designed for 100 flights. Optimum crew was four, a pilot, co-pilot, and two cosmonauts specialising in EVA and payload operation. These four crew members were on the upper deck and all were provided with ejection seats. However up to ten crew could be carried by using additional seats on the lower deck. Four to six of these would be researchers, depending on the mission. Buran could achieve a 1,700 km cross range on re-entry, protected by 39,000 tiles of two types. Synthetic quartz fibre tiles were used in low temperature areas, and black high-temperature organic fibre tiles were used on high temperature areas. Carbon-carbon material was used for the nose and wing leading edges.
Modular universal equipment was developed for Buran that would be used on other spacecraft and space stations. These included the docking module, airlock, manipulator arm, and payload cradle. These items represented 12,000 kg of Buran's lift-off mass.
The Buran launch sequence was as follows:
 | Bottom of Buran - Bottom of Buran, showing how thermal tiles were placed. Credit: © Mark Wade. 17,673 bytes. 496 x 297 pixels. |
Payload Bay - The OPG payload section, 18.55 m x 4.65 m, also housed the guidance system electronics, the engine control systems, propellant piping and conduits, the electric fuel cell generators, and the fuel cell reactant tanks. According to mission, within the payload bay were also the SKPG payload cradle holding fixture and associated electrical/electronic/hydraulic/pneumatic interfaces; the SM docking module (spherical, 2.67 m diameter with a cylindrical tunnel); the APAS androgynous docking unit.
Base Block - The BB base block housed the modular ODU orbiter engine unit, three VSU auxiliary power units (split into left and right modules), the hydraulic system, and a hermetically sealed instrument compartment.
Wings - the wing profile was developed by TsAGI after many tests at all speed regimes. The basic double delta wing has a 45 degree sweep, with 78 degrees of sweep at the wing gloves. The wing form consists of symmetrical base file, with thickness 12% of cord, 40% of length. Fuselage is of cylindrical form, with a 14 degree transition section. The vertical stabiliser has a 60% sweep.
 | Space - Earth! - Space - Earth! First space tourism flight! Poster for Buran ride in Gorky Park. Credit: © Mark Wade. 29,565 bytes. 289 x 447 pixels. |
Major systems:
Guidance - Buran was equipped with an AIK redundant flight control system and gyro platform. Unlike Soyuz, this was a full-time system, which did not require platform alignment and spin-up for each manoeuvre. The automated flight system could detect system failures, and switch to backup equipment. Alternate programs were stored for emergency flight situations. All docking and manipulator arm operations were automated as well, the sole exception being the final stage of docking when using the manipulator arm. Radio navigation systems built by Vympel, developed by NIP Gromov, integrated several radio navigation aids to provide redundant means of precision automatic landing. Manual control was used only as a backup when all else failed.
 | Buran Back Side - Closeup of Buran tail area, as displayed at the Paria Air show shortly after its spaceflight. Credit: © Mark Wade. 59,500 bytes. 576 x 395 pixels. |
Buran Development
Over 232 experimental test stands were built during Energia development. Development of the Buran orbiter required a further 100 test stands, 7 complex modelling stands, 5 flying laboratories, 6 full-scale mock-ups, and 2 flight mock-ups (OK-ML-1 and OK-MT).
Functional system qualification tests were conducted before first flight on 780 individual equipment items and 135 systems. Rigorous qualification tests were conducted of all structural components. Structural elements were tested individually, and then in ever larger assemblies. 1000 experiments of various types were conducted on 600 structural subassemblies. The result was that the flight data very closely followed predictions, and both the launch vehicle and orbiter flew successfully on their very first flights. This was in sharp contrast to the numerous early failures of the Soyuz and N1 programmes in the 1960's.
Six full-scale functional mock-ups of Buran were built:
 | Drawing of Buran LV Credit: © Mark Wade. 4,158 bytes. 173 x 464 pixels. |
 | Buran control panel - Control panel of Aero-Buran jet-powered approach and landing test version of Buran. First Aero-Buran analogue rolled out in 1984. This Aero-Buran was worn out and would not be used again after 24 flights to April 1988. Credit: RKK Energia. 10,251 bytes. 187 x 284 pixels. |
In addition to the full-scale mock-ups, the following were instrumental in Buran development:
 | Buran at Baikonur 1 Credit: © Mark Wade. 26,255 bytes. 574 x 364 pixels. |
Buran Assembly / Processing / Launch / Landing Facilities
Using the N1 facilities at Baikonur as a starting point, major modifications had to be made and several new buildings erected to assemble and launch Buran at the remote Baikonur cosmodrome. The land-locked location of Baikonur meant that major assembly work on the orbiter and launch vehicle had to be conducted on site, instead of at the subcontractors factories. The liquid oxygen and liquid hydrogen tanks of the core, and the Buran orbiters, were flown to Baikonur on the back of the 3M-T transport. The booster stages and all other material and equipment were brought in by rail.
 | Buran LV Credit: © Mark Wade. 8,922 bytes. 379 x 464 pixels. |
 | Buran Credit: © Mark Wade. 1,104 bytes. 254 x 119 pixels. |
 | Buran Icon Credit: © Mark Wade. 494 bytes. 134 x 65 pixels. |
From 1976 to 1977 two Block R stages underwent thorough tests of all of their systems. The Block R could have operated up to 7 hours with 7 restarts. Not adopted for production for unknown reasons.
The MKS draft project was completed on 12 December 1976.The military assigned the system the index number 1K11K25 and the launch vehicle the article number 11K25.
A critical step in any Soviet project, this approved the design and paved the way for development to begin.
The government decree 1006-323 set out the development plan. The flight test plan was for first launch of the booster in 1983, with the payload being an unmanned OK-ML-1 mock-up of the orbiter. This would not have a heat shield and remain attached to the booster. A second mock-up, OK-ML-2, would be used on the second launch, but be separated from the vehicle after burnout. However it would also be without heat shield, and be expended. The first flight Buran was to fly unpiloted in 1984. Manned flights were to be routine by the 1987 seventieth anniversary of the Soviet Union.
 | Buran LV - Buran LV on Launch Pad Credit: RKK Energia. 37,631 bytes. 303 x 480 pixels. |
3M bomber was selected to carry piggy-back Energia core stage components and Buran orbiters.
Buran engineering details were definitised and drawing release began to the production shops.
In 1979 the EUK13 dimensional model of the Energia launch vehicle was delivered to Baikonur for handling demonstrations and production of tooling.
First test of the modified 3M bomber, converted to carry piggy-back Energia core stage components and Buran orbiters.
Continued development problems with the Energia booster rockets led to a management shake-up at the Yuzhnoye design bureau.
 | Buran launch Credit: RKK Energia. 8,266 bytes. 313 x 181 pixels. |
Subscale Spiral spaceplane. After 1.25 revolutions of the earth, deorbited and recovered by Soviet naval forces in the Indian Ocean at 17 degrees South, 98 degrees East, 560 km south of Cocos Islands. Made a 600 km cross-range maneuver during reentry. The recovery was filmed by an Australian Orion reconnaissance aircraft, revealing the configuration to the West for the first time.
The 3M-T transport aircraft was completed and began delivery of central block propellant tanks and structural elements for construction of a realistic mock-up of the Energia booster. The 3M-T was a heavily modified M-4 bomber, and was limited to 50 tonnes loads carried on the top of the fuselage.
The 4M Energia launch vehicle high fidelity mock-up was completed at Baikonur.
 | Buran LV Credit: RKK Energia. 15,583 bytes. 281 x 287 pixels. |
The 4M Energia mock-up was used for dynamic/vertical/load tests in May-October 1983. The 4M was then returned to the shop for fitting of complete functional propellant systems.
Suborbital test of 1/8 scale model of Buran. Typical trajectory: ascent to 120 km; pitch down to drive model in atmosphere at 45 degree at Mach 18.5. None were reflown but at least 4 were recovered.
The OK-KS Buran systems test stand was built at NPO Energia to conduct tests not possible on other stands. These included electrical layout, pneumo-hydraulic tests in abort conditions, EMI tests, failure mode response, telemetry, interface with the launch vehicle, software systems test. The test series was completed in March 1984. 77% of the tests of the OK were automated, compared with only 5% for the Soyuz-TM.
 | Buran at Baikonur 3 - View of tail section of Buran at the MIK in Baikonur. Credit: © Mark Wade. 32,294 bytes. 389 x 576 pixels. |
Subscale Spiral spaceplane. In a new mission profile, braked out of orbit over the South Atlantic and was recovered in the Black Sea after one orbit of the Earth.
The OK-ML-1 mock-up arrived atop the 3M-T transport aircraft. OK-ML-1 was originally to have been used in the first launch of the Energia, by the end of 1983. But the program was years behind schedule, and in the end the OK-ML-1 was used for handling and pad compatibility tests.
Suborbital test of 1/8 scale model of Buran. Typical trajectory: ascent to 120 km; pitch down to drive model in atmosphere at 45 degree at Mach 18.5. None were reflown but at least 4 were recovered.
 | Buran at Baikonur 2 - View of underside of Buran spaceplane stored in the Energia MIK at Baikonur. Credit: © Mark Wade. 23,611 bytes. 575 x 330 pixels. |
Last flight of the subscale Spiral spaceplane. Recovered December 19, 1984 5:26 GMT, in the Black Sea after one orbit of the Earth.
Maximum speed 45 kph. Time 5 minutes. Thereafter to PRSO test stand for full-scale equipment tests; then to PDST pilot-dynamics test stand for further tests.
System specification issued for An-225 heavy transport, which will replace 3M-T for transport of Energia core stage components and the Buran spaceplane. The aircraft will also be the launcher for the MAKS spaceplane.
From March-October 1985 the Ts core stage was back on the UKSS test/launch stand for cold flow tests. A total of nine cryogenic fuelling cycle were completed with the 4M Energia mock-up, representing the first operational use in the world of super-chilled hydrogen.
Suborbital test of 1/8 scale model of Buran. Typical trajectory: ascent to 120 km; pitch down to drive model in atmosphere at 45 degree at Mach 18.5. None were reflown but at least 4 were recovered.
Maximum speed 200 kph. Time 14 minutes.
Maximum speed 270 kph. Time 12 minutes.
Maximum speed 300 kph.
Maximum speed 480 kph. Maximum altitude 1500 m. Time 12 minutes.
Maximum speed 170 kph. Time 12 minutes.
Maximum speed 520 kph. Maximum altitude 3000 m. Time 36 minutes.
By January 1986 it was clear that the project, now three years behind schedule, had no prospect of completion due to problems in obtaining deliveries of equipment for Buran, numerous problems in assembling the orbiters and lack of manpower at Baikonur, and a general loss of management focus. Minister O D Bakhnov called a large group of industry leaders to the cosmodrome to review measures to concentrate and accelerate the remaining work. Three 'Tiger Teams' were set up. The first, led by Semenov, was to finish the flight Buran orbiter and associated facilities in time for a third quarter 1987 launch. The second, led by B I Gubanov, was to finish the Energia launch vehicle and fly it, without the Buran mock-ups if necessary, at the earliest possible date. The third group, led by S S Banin, was to complete the assembly and launch facilities.
The first Buran payload, 37KB module s/n 37070, is delivered by freight car. The 37KB modules, similar to the Kvant module of the Mir space station, were to be standard on the early Buran flights. 37KB-37070 itself primarily contained instrumentation to measure the performance of the orbiter and its structure on its first flight.
This was to be the first 20 second Energia main engine firing test. It was terminated at 2.58 seconds when the automatic control system detected a slow spool up of an engine turbine. In a the first attempt at a full-duration test helium leaks contaminated electro-hydraulic systems, leading to a situation where the tanks could not be drained. An engineering brigade had to work on the fuelled booster for 55 minutes, attach another helium tank, which led to successful de-fuelling of the vehicle.
Time 14 minutes.
Maximum speed 540 kph. Maximum altitude 4000 m. Time 23 minutes.
Maximum speed 530 kph. Maximum altitude 4000 m. Time 22 minutes.
Time 25 minutes.
Time 23 minutes.
Following the decision to make the first flight of Energia without a Buran orbiter, in August-September 1986 further UKSS tests of Energia were conducted. These used a dummy payload and solid rocket motors to simulate loads from the booster rockets.
The second engine test was a complete success, the engine running for 390 seconds. This test required the entire city of Leninsk to be without water for ten days in order to accumulate enough water for the UKSS cooling system.
First automatic landing from 4000 m altitude. Time 24 minutes.
Time 17 minutes.
Suborbital test of 1/8 scale model of Buran. Typical trajectory: ascent to 120 km; pitch down to drive model in atmosphere at 45 degree at Mach 18.5. None were reflown but at least 4 were recovered.
Time 17 minutes.
Time 28 minutes.
Time 19 minutes.
Time 2 minutes.
Time 25 minutes.
Due to delays in completion of the enormous static test facility at Baikonur, which could test the entire Energia vehicle stack, it was decided to launch the vehicle without the verification the tests would provide. The launch of 6SL was planned for 11 May 1987 at 21:30 Moscow time. It was delayed five days when a leak was detected in the Block 3A electrical distribution section, then by another hour due to a fault LH2 thermostat. The launch vehicle performed successfully, but the Polyus payload failed to inject itself into orbit due to a guidance system failure.
Time 20 minutes.
Time 19 minutes.
Suborbital test of 1/8 scale model of Buran. Typical trajectory: ascent to 120 km; pitch down to drive model in atmosphere at 45 degree at Mach 18.5. None were reflown but at least 4 were recovered.
Automatic landing. Time 21 minutes.
Time 19 minutes.
Time 22 minutes.
Time 32 minutes.
Time 20 minutes.
Time 19 minutes. Final Buran Analog flight test. At the same time development of the auto-land system aboard the Tu-154 test bed is completed as well.
All flight and development tests having been completed, Buran is certified as ready for spaceflight.
Suborbital test of 1/8 scale model of Buran. Typical trajectory: ascent to 120 km; pitch down to drive model in atmosphere at 45 degree at Mach 18.5. None were reflown but at least 4 were recovered.
Unmanned test of Soviet shuttle. Landed November 15, 1988 06:25 GMT. Buran was first moved to the launch pad on 23 October 1988. The launch commission met on 26 October 1988 and set 29 October 06:23 Moscow time for the first flight of the first Buran orbiter (Flight 1K1). 51 seconds before the launch, when control of the countdown switched to automated systems, a software problem led the computer program to abort the lift-off. The problem was found to be due to late separation of a gyro update umbilical. The software problem was rectified and the next attempt was set for 15 November at 06:00 (03:00 GMT). Came the morning, the weather was snow flurries with 20 m/s winds. Launch abort criteria were 15 m/s. The launch director decided to press ahead anyway. After 12 years of development everything went perfectly. Buran, with a mass of 79.4 tonnes, separated from the Block Ts core and entered a temporary orbit with a perigee of -11.2 km and apogee of 154.2 km. At apogee Burn executed a 66.6 m/s manoeuvre and entered a 251 km x 263 km orbit of the earth. In the payload bay was the 7150 kg module 37KB s/n 37071. 140 minutes into the flight retrofire was accomplished with a total delta-v of 175 m/s. 206 minutes after launch, accompanied by Igor Volk in a MiG-25 chase plane, Buran touched down at 260 km/hr in a 17 m/s crosswind at the Jubilee runway, with a 1620 m landing rollout. The completely automatic launch, orbital manoeuvre, deorbit, and precision landing of an airliner-sized spaceplane on its very first flight was an unprecedented accomplishment of which the Soviets were justifiably proud. It completely vindicated the years of exhaustive ground and flight test that had debugged the systems before they flew.
First flight of the An-225 super-heavy transport with the Buran spaceplane mounted atop it.
No known mission (with the end of SDI and the cold war) - plus the project manager was one of the 1991 coup plotters. Total cost 20 billion rubles at time of cancellation.
