Category Energiya-Buran

Buran was a double-delta winged spacecraft capable of putting people and cargo into low Earth orbits and returning them to a controlled gliding landing. Aerodynamic­ally, it was a near-copy of the US Space Shuttle Orbiter. The Soviet orbiter was 36.37m long and had a maximum diameter of 5.50 m. Buran’s airframe consisted of the crew module shell, the forward fuselage, the mid fuselage, the aft fuselage, a body flap, delta wings with elevons, and a vertical tail. The airframe was largely made of aluminum alloys such as D16 (also widely used in aircraft) and 1201 (specifically developed for Buran), designed to withstand temperatures between about — 130°C and +150° C. Other materials used were various titanium alloys for areas experiencing higher stresses as well as a variety of high-temperature and tensile steels. Playing a key role in the development of these materials was the All-Union Institute of Aviation Materials (VIAM). All elements of the airframe were covered by reusable thermal insulation to protect the structure against the wide range of temperatures experienced during ascent, in orbit, and during re-entry.

The forward fuselage (Russian acronym NChF) was 9 m long, 5.5 m wide, and 6 m high. It housed the pressurized crew module and forward reaction control system thrusters. Structurally, it consisted of the nosecap, the forward thruster module, and an upper and lower section. The latter two were manufactured separately to allow the pressurized crew module to be inserted during final assembly.

The mid fuselage (SChF) was 18.5 m long, 6 m wide and 5.5 m high and contained the payload bay, the nose landing gear, the electricity-generating fuel cells, and their fuel tanks, wiring for the power system and flight control system, various tanks for the environmental control system and thermal control system, and also propellant lines connecting the forward and aft thruster sections. Twenty-six frame assemblies provided stabilization of the mid fuselage structure. Longerons on either side absorbed the bending loads of the vehicle and contained the hinges of the payload bay doors. Mounted in the side walls were several doors to vent the vehicle’s unpressurized compartments and to service the fuel cells. The front part of the mid fuselage housed the nose gear wheel well, nose landing gear, and nose gear

doors. The nose gear was situated farther to the back than the Orbiter’s, where it is part of the forward fuselage.

The payload bay doors consisted of port and starboard doors hinged at each side of the mid fuselage. They were 18.5m long and had a gross area of 144 m2. Each door was made up of four segments, each of them resting on 12 hinges. The doors were held closed by a total of 33 latches, consisting of 16 bulkhead latches (eight forward and eight aft) and 17 payload bay door centerline latches. The doors were composed of a lightweight graphite-epoxy composite material (KMU-4E) that was much lighter than the D-16 aluminum alloy used in most of Buran’s airframe. At a later stage it was supposed to have been replaced by an even lighter material called KMU-8. The total mass of Buran’s doors was 1,625 kg, which was 620 kg lighter than the mock-up aluminum doors built for the BTS-002 vehicle that flew the atmospheric approach and landing tests. The doors also served as a strongback for the radiator panels that allowed heat rejection in orbit.

The aft fuselage (KhChF) was 3.6 m long, 5.5 m wide, and 6 m high. It housed the Combined Engine Installation with its orbital maneuvering engines and steering

thrusters, the Auxiliary Power Units, the hydraulic system, and a pressurized equip­ment bay. On the outside were attach points for the tail, the body flap, the wings, and the brake chute.

Buran’s double-delta wings provided aerodynamic lift and control of the vehicle during atmospheric flight. The vehicle’s lift-to-drag ratio was 1.3 during the hyper­sonic phase of re-entry and 5.6 at subsonic speeds. Wingspan was 23.92 m and total area 250 m2 (virtually identical to the values for the Space Shuttle Orbiter). The wings had a 45° degree sweep on the inner leading edge and a 79° sweep on the outer (vs. 45° and 81° on the Shuttle Orbiter). The wings were positioned slightly more forward on the fuselage than those of the Space Shuttle, helping to adjust the vehicle’s center of gravity in the absence of heavy, aft-mounted main engines.

Elevons provided pitch and roll control during atmospheric flight. They were divided into two segments for each wing, with each segment being supported by three hinges. Pitch control was achieved by deflecting all elevons in the same direction (elevator function) and roll control by deflecting the left-wing and right-wing elevons in opposite directions (aileron function). Each elevon traveled 35 degrees up and 20 degrees down (compared with 40° and 25° for the Space Shuttle Orbiter).

The tail (or “vertical stabilizer’’) consisted of a structural fin surface and a two-part rudder/speed brake. Its total area was 39 m2 and that of the rudder/speed brake 10.5 m2. As on a conventional airplane, the rudder provided yaw control when both panels were deflected left or right, but by splitting each of its two panels into two halves it also acted as a speed brake, a feature unique to rapidly descending gliders such as Buran and the Shuttle. The segments could be deflected in the same direction for rudder control of plus or minus 23° (27° on the Orbiter) and the halves could be moved in opposite directions for speed brake control for a maximum of about 43.5° each (49.3° on the Orbiter).

An aerodynamic surface not seen on conventional airplanes is the body flap, attached to the bottom rear of the aft fuselage. With a maximum deflection angle of 30°, it provided pitch control trim to reduce elevon deflections [10].

Buran had 38 primary thrusters (“Control Engines’’ or UD) (exactly the same number as on the Space Shuttle Orbiter) and eight verniers (“Orientation Engines’’ or DO) (two more than on the Orbiter). Together the primary thrusters and verniers formed the Reaction Control System (RSU). The primary thrusters provided both attitude control and three-axis translation, and the verniers only attitude control. They were used for these functions during the launch, separation from the core stage, on-orbit, and re-entry phases of the flight (up to an altitude of 10 km). If needed, some of the UD thrusters could also act as a back-up for the DOM engines.

The UD thrusters (17D15), built in-house at NPO Energiya, had a thrust of 390 kg and a specific impulse between 275 and 295 s. Unlike the DOM engines, they used gaseous rather than liquid oxygen as an oxidizer. This was obtained with a small turbopump assembly mounted on the ODU LOX tank. First, liquid oxygen from the LOX tank passed through the pump, where its pressure was increased to 78.4 MPa. Then it entered a gas generator where it was ignited with a minute amount of sintin fuel (ratio of 100: 1) to form a mix of gaseous oxygen, carbon dioxide, water vapor, and droplets with a temperature of 60°C. After any residual liquids had been dumped

overboard, the gaseous oxygen was used to drive the turbine and was then stored in separate tanks at pressures ranging from 2.45 to 4.9 MPa. From there it was delivered to the combustion chamber to react with liquid sintin through electrical ignition. Each UD thruster could be fired for a duration of anywhere between 0.06 and 1,200 seconds and be ignited up to 2,000 times during a single mission. The thrusters were designed to sustain 26,000 starts and 3 hours of cumulative firing.

The DO verniers (17D16 or RDMT-200K) provided 20 kg of thrust and had a specific impulse of 265 s. They were developed by the Scientific Research Institute of

Machine Building (Nil Mashinostroyeniya) in Nizhnyaya Saida, which had been a branch of the Scientific Research institute of Thermal Processes (Nil TP) until 1981 and specialized in small thrusters for spacecraft. The RDMT-200K was probably a cryogenic version of the RDMT-200, a thruster with similar capabilities built for the Almaz space station but burning storable propellants. The verniers were similar in design and operation to the UD thrusters, but used liquid oxygen and a different cooling system. They were intended for short-duration burns with an impulse time between 0.06 and 0.12 seconds and could be ignited up to 5,000 times during a single mission. Thrusters based on the RDMT-200K were supposed to fly on the upper stage of the Yedinstvo/ULV-22 rocket, a launch vehicle studied by the Makeyev bureau in the late 1990s to fly from Australian territory.

Aside from the ODU engines and thrusters, Buran had four small solid-fuel motors (thrust 2.85 tons each) to instantly separate the vehicle from the Energiya core stage in case of a multiple engine or other catastrophic launch vehicle failure. Presumably developed by NPO iskra, they were situated in the nose section of the vehicle and should have given Buran enough speed to stay clear of the out-of-control rocket after separation. They were not supposed to be used in a standard separation from the core stage after main engine cutoff. The solid-fuel motors were apparently not installed on the first flight vehicle that made the one and only Buran mission in 1988.

The Energiya-Buran launch profile offered more rescue options for the crew than that of the Space Shuttle, mainly because of the use of liquid-fuel rather than solid – fuel boosters. Whereas a Solid Rocket Booster (SRB) failure will almost always result in the loss of vehicle and crew (as tragically demonstrated by the Challenger disaster), an engine failure on one of Energiya’s four strap-ons would not necessarily have had catastrophic results. Buran cosmonauts had the following escape options.

Pad emergency escape system

In case of an emergency on the launch pad the crew could egress Buran and flee to an underground bunker using the pad emergency escape system. Unlike the slidewire baskets used on the Space Shuttle launch pads, the cosmonauts were to glide down a giant chute and subsequently seek shelter in bunkers under the launch pad (see Chapter 4).

Ejection seats

For its manned test flights Buran was to be equipped with ejection seats, allowing the crew members to escape through two overhead hatches in case of an emergency on the pad, in the early stages of launch and the final phases of landing. Ejection seats were also flown on the four two-man test flights of the US Space Shuttle Columbia, but were disabled for Columbia’s first operational mission (STS-5, which carried two mission specialists on the flight deck) and eventually removed altogether. The Russians were planning both two-man and four-man test flights and the intention was to have ejection seats for all cosmonauts irrespective of crew size. With a crew of four, the two non-pilots would have been seated in the front part of the mid-deck and could have been ejected via two hatches mounted in between the forward reaction control system and the six forward cockpit windows. In that configuration the front equipment bay in the mid-deck would have been moved to the rear. The ejection seats would have been removed for flights carrying more than four cosmonauts.

Buran’s ejection seats (called K-36RB or K-36M11F35) belonged to the family of K-36 seats of the Zvezda organization that are standard equipment on Soviet high-performance combat aircraft. More than 10,000 K-36 seats had been produced by the early 1990s and several hundred real ejections had been made with very high survival rates.

The K-36 seats are based on a modular design to which systems are added or deleted depending on the specific aircraft on which they are installed. The modifica­tions for Buran were needed not so much for the landing phase, but mainly to pull the cosmonauts away to a safe distance from the rocket in case of a pad or launch accident. For that purpose they were equipped with a small solid-fuel rocket that would have been needed only for ejection during launch and on the pad (after retraction of the crew access arm). In the latter scenario the K-36RB would have been able to reach an altitude of 300 m in order to clear the 145 m high rotating service structure which would have been in its path. The pilot was supposed to come down 500 m from the pad in a matter of just 10 seconds.

Another feature unique to the K-36RB was an under-seat stabilization system with drag parachutes that would be used up to an altitude of about 1 km. The system’s two booms were separated along with the solid-fuel rocket at a point near the upper portion of the seat’s trajectory. This was installed in addition to a standard two-boom upper stabilization system with end-mounted parachutes.

The cut-off altitude and speed for the use of the K-36RB during launch would have been 30-35 km and Mach 3.0-3.5, respectively (compared with 24 km and Mach 2.7 for the Shuttle seats), which roughly equates to T + 100 seconds in a normal

launch profile. That limit was determined by the ability of the Strizh pressure suits to protect the pilot from the thermal stresses experienced in an ejection. The Strizh suits were covered with special heat-resistant material to protect the pilot against heating caused by the high aerodynamic loads during ejection. The K-36RB could also be used during landing, from the moment speed was reduced to Mach 3.0-2.5 all the way to wheels stop. The seats were also installed on the BTS-002 atmospheric test model (as they were on Enterprise for the Approach and Landing Tests). The ejection seats could be activated by the crew, by on-board automatic devices, or by a command from the ground.

Also unique to the K-36RB was a computer linked to Buran’s computers that ensured that the seat was configured for one of five ejection modes corresponding to

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the orbiter’s launch or landing phase. Mode 1 was for ejection on the launch pad, mode 2 for ejection during initial ascent, mode 3 for high-Mach/high-altitude ejections, mode 4 for the landing approach, and mode 5 for the final approach, touchdown, and roll-out.

The K-36RB was tested in at least three ways with mannequins clad in Strizh pressure suits. In one method the seat was installed in a ground-based mock-up of Buran’s cockpit and in another in the aft cockpit of a converted two-seater MiG – 25RU training aircraft (serial number 0101). A rather original way was found of testing the ejection seats and associated escape suits at much higher velocities and altitudes. An experimental version of the seats called K-36M-ESO was carried as a piggyback payload on five unmanned Soyuz rockets carrying Progress resupply ships between September 1988 and May 1990 (Progress 38, 39, 40,41, and 42). The ejection seats were fitted inside the rocket-powered tower atop the launch vehicle and ejected at altitudes between 35 and 40 km and speeds between Mach 3.2 and 4.1.

Emergency Separation

Emergency Separation (Russian acronym EO) would have been activated if a serious launch vehicle problem had forced shutdown of all engines above the altitude where the ejection seats could be used. In that scenario, Buran could have swiftly separated from the core stage using four small solid-fuel motors in its nose section and subse­quently attempted to stabilize itself to perform a manual emergency landing on a runway downrange after having dumped excess propellant from the ODU engine system. In case no emergency runway was available, the crew could still have used their ejection seats once Buran was stabilized and had reached a safe altitude.

NASA studied a similar escape option for the Shuttle called “Fast Separation” that would have allowed the Orbiter to separate from the External Tank in approxi­mately three seconds in case of an SRB failure. However, analysis showed that if this is attempted while the SRBs are thrusting, the Orbiter would “hang up” on its aft attach points and pitch violently, probably resulting in the destruction of the vehicle. Similarly, the Russians concluded that Emergency Separation would be hard to achieve without Buran hitting the core stage, especially when the stack experienced high aerodynamic pressures in the early stages of the launch, virtually all the way to separation of the strap-on boosters. Moreover, safely landing the vehicle in such a scenario would have required a very elaborate and costly network of emergency runways all the way downrange.

Since the main production facilities for Energiya-Buran were located at great dis­tances from Baykonur, a practical way had to be found of transporting the various elements to the cosmodrome. This was not so much of a problem for the 3.9 m wide strap-on boosters. The first stage of the 11K77/Zenit rocket, which served as the basis for the strap-ons, had already been tailored for rail transport to the launch site and the strap-ons could therefore use the same infrastructure. However, this was not the case for Buran itself and the core stage, which were too big to be transported by conventional means. There was also the problem of returning Buran to Baykonur in case it was forced to make an emergency landing on its back-up landing strips in the Crimea and the Soviet Far East.

One way of avoiding this problem would have been to concentrate the bulk of the assembly work at the cosmodrome itself. In other words, elements of Buran and the core stage would have been transported to the cosmodrome in many small pieces using conventional means of transport and then assembled together at the launch site. This had been done with the massive first stage of the N-1 rocket, the major parts of which were welded together at the cosmodrome. However, for Energiya-Buran this was not considered a viable solution. It would have required the construction of costly new facilities at the launch site and thousands of skilled engineers and workers would have had to be sent away from their home base on lengthy assignments to the cosmodrome.

Transportation by road and/or water was considered, but all proposals were deemed too costly because of the need to perform major construction work and make changes to existing infrastructure. One option studied for the core stage was to transport it by barge over the Volga river from Kuybyshev to the Volgograd/ Astrakhan region and from there to Baykonur over a specially constructed railway.

The only solution left was to transport the elements by air, either by helicopter or airplane. Serious consideration was given to using the Mi-26 helicopter of the Mil design bureau, which had become operational just as the Energiya-Buran program got underway in the second half of the 1970s. The Mi-26 is still the heaviest and most powerful helicopter in the world, capable of lifting about 20 tons. In this scenario, the

orbiter airframe or elements of the core stage would have been mounted on an external platform and then lifted by a combination of two to four Mi-26 helicopters (depending on the mass of the payload). Test flights with the mid fuselage of a defunct Il-18 aircraft were staged from the Flight Research Institute in Zhukovskiy, but showed that this transportation technique was cumbersome and even dangerous. During one test flight the pilots were forced to drop the payload after it had begun dangerously swaying from one side to the other due to air turbulence. Another problem was the helicopter’s limited range, which would have made it necessary to make several refueling stops on the way to Baykonur.

As foreseen by the government decree of 17 February 1976, the Ministry of the Aviation Industry began looking at a number of aircraft to solve the transportation problem. Two airplanes considered were the Tupolev Tu-95 and Ilyushin Il-76, but it soon turned out they would not be up to the task at hand. The most advanced Soviet cargo plane available at the time was the An-22 Antey of the Antonov design bureau in Kiev. In service since 1965, it was capable of lifting 60-80 tons. Engineers studied the possibility of mounting Energiya-Buran hardware on the back of the aircraft or inside by increasing the diameter of its aft fuselage to 8.3 m (the latter version was known as An-22Sh), but both configurations presented insurmountable aerodynamic and stability problems. A more capable Antonov cargo plane, the An-125 Ruslan, was under development in the late 1970s. However, its single vertical fin made it impossible to install long payloads and its relatively small undercarriage could not handle high-crosswind landings with a big payload installed on the back of the fuselage.

GKNII in Akhtubinsk began the selection process in 1978. The job was offered to all pilots working for GKNII and eight pilots displayed interest in the project [18]. They were:

• Ivan Ivanovich Bachurin;

• Aleksey Sergeyevich Boroday;

• Viktor Martynovich Chirkin;

• Vladimir Mikhaylovich Gorbunov;

• Vadim Oleynikov;

• Vladimir Yemelyanovich Mosolov;

• Nail Sharipovich Sattarov;

• Anatoliy Mikhaylovich Sokovykh.

On 1 December 1978 six of them (Bachurin, Boroday, Chirkin, Mosolov, Sattarov, and Sokovykh) were cleared by the GMVK to begin their OKP training in January

1979. Oleynikov had apparently been medically disqualified [19]. Gorbunov later claimed that he also began OKP, but left the program at his own initiative, having come to the conclusion that there was no future for him in Buran. In fact, he had told his commander in Akhtubinsk that he was signing up for Buran as long as he could combine that with his job in flight testing the MiG-29, a program he felt offered him much more perspective [20].

The six remaining pilots commuted between Akhtubinsk and TsPK in training cycles of between one and two months. While in Akhtubinsk, they continued their test flying for the Air Force. Not all of them would finish OKP. In April

1980, Nail Sattarov was flying a Tupolev Tu-134, a medium-size passenger plane, when he decided to have a little fun and perform a roll maneuver with the aircraft. Although colleagues of his have stressed that this was something everyone had done at least once, Sattarov had the bad luck of being caught. Besides a reprimand and temporary grounding, he was also removed from the Buran training group. Apparently, his commanders felt that such undisciplined behavior disqualified him from being a cosmonaut. Interestingly, although this is the reason that is usually given as the one that ended his cosmonaut career, Sattarov himself insists that the incident had nothing to do with him discontinuing OKP and leaving the group. Instead, he claims that in late March or early April 1980 he had indicated to his commanders at GKNII that he felt his flying career was going nowhere if he would continue to train as a cosmonaut, and that his request to return to test flying full time was granted [21].

The remaining five candidates completed OKP in November 1980 and were awarded their certificates of cosmonaut-testers on 12 February 1982. All five resumed their test pilot duties at GKNII, with their Buran-related work as a secondary task.

Shortly afterwards, Viktor Chirkin came to the conclusion that the Buran program was not going the way it should and he seriously doubted the vehicle would ever mature to the point that manned flights by Air Force test pilots would materialize. At his own request, he was relieved of his duties in the cosmonaut group in 1981. Chirkin went on to become a Major General, and in 1995 a Hero of the Russian Federation.

Anatoliy Sokovykh was less lucky. He too returned to test flying but in 1985 became involved in an incident that cost several people their lives. In one version, one of his crew members accidentally shot down another plane, but another version has it that his crew accidentally destroyed the wrong ground target, killing several soldiers. Sokovykh had not made the mistake himself, and it has even been said that the crew itself had only followed instructions from the ground. However, as commander of the aircraft he was held responsible and reportedly was demoted. In addition, with such a blot on his reputation, he could not maintain his position as cosmonaut [22].

By then, it had already been decided that the group needed fresh blood, and in August 1985 the GMVK added three new test pilots (from eight candidates that had originally been considered) to the group. They were:

• Viktor Mikhaylovich Afanasyev;

• Anatoliy Pavlovich Artsebarskiy;

• Gennadiy Mikhaylovich Manakov.

The three joined another group of cosmonaut candidates to undergo OKP in Star City. Most of the others had also been selected for the Buran program. They were, from LII, Magomed Tolboyev, Yuriy Sheffer, Ural Sultanov, Sergey Tresvyatskiy, and Viktor Zabolotskiy and, from NPO Energiya, Aleksandr Kaleri, Sergey Krikalyov, and Sergey Yemelyanov. The final candidate was Yuriy Stepanov, a physician who came from the Institute of Medical and Biological Problems (IMBP).

However, soon after Afanasyev, Artsebarskiy, and Manakov finished OKP in May 1987, they were approached by TsPK cosmonaut training chief Vladimir Shatalov with the request to transfer to the TsPK cosmonaut team. That same offer was extended to Ivan Bachurin, Aleksey Boroday, and Vladimir Mosolov [23]. Shatalov, who was in dire need of new crew commanders, considered the six pilots

readily available candidates who had all finished OKP and could easily move over to the TsPK ranks. In addition, the Buran program was suffering delays, which might make the choice easier for them.

Afanasyev, Artsebarskiy, and Manakov accepted the offer and were officially included in the TsPK team in January 1988. However, Bachurin, Boroday, and Mosolov declined. They were preparing for the approach and landing test program on BTS-002 and felt that was more of a challenge for test pilots. As Mosolov put it: “We didn’t want to be like dogs instead of crews. We wanted to fly with techniques that we could control and manage’’ [24]. In addition, Aleksey Boroday has said that the GKNII commander, wary of losing all his Buran cosmonauts to TsPK, had refused to consider a transfer of the three senior pilots [25].

Meanwhile, Mosolov was dismissed from the GKNII group in 1987 because of his divorce [26]. This left the GKNII team with only two members and it was decided that the group needed to be expanded yet again.

Ivan Bachurin was given the task to pre-select young test pilots and invite them to become members of the group. Seven pilots decided they wanted to join and took the initial medicals, which were held in TsPK’s medical department. Four of them didn’t pass, and this was a reason for two more to decline. They decided they didn’t want to go to TsNIAG, the central military hospital, and risk being grounded from test flying if they would be declared medically unfit for the Buran program. The only one left was Anatoliy Polonskiy [27].

In the end, Polonskiy passed the medical board in February 1988 along with two other candidates and on 25 January 1989 all three were confirmed by the GMVK:

• Anatoliy Borisovich Polonskiy;

• Valeriy Ivanovich Tokarev;

• Aleksandr Nikolayevich Yablontsev.

Two months later, three more pilots passed the medical commissions. They were:

• Valeriy Yevgenyevich Maksimenko;

• Aleksandr Sergeyevich Puchkov;

• Nikolay Alekseyevich Pushenko.

In May 1989, the six began the basic cosmonaut training course in Star City, even though the GMVK would only officially confirm the selection of Maksimenko, Puchkov, and Pushenko on 11 May 1990. The six graduated on 5 April 1991, all of them getting the qualification of cosmonaut-tester with the accompanying certificate.

It should be noted that after all the selections mentioned above the GKNII pilots initially had a status similar to that of the LII pilots until 1981—that is, something comparable with payload specialists in the United States. It was not until 7 August 1987 that the USSR Ministry of Defense officially set up a team of what could be considered GKNII “career cosmonauts”. They were based at a branch of GKNII in the Moscow suburb of Chkalovskiy, right next to Star City. The first to be included in the team by that same order were Bachurin and Boroday, with Bachurin named as commander.

Added to the team on 25 October 1988 was Leonid Kadenyuk, who had been a member of TsPK’s 1976 Buran selection, but had been dismissed after divorcing his wife. Since he had already undergone OKP, he could begin working with Bachurin and Boroday right away. In fact, all three were assigned two years later to a mission in which a Soyuz vehicle would link up with an unmanned Buran to test some of its systems in orbit.

On 8 April 1992 the Chkalovskiy team was expanded with Puchkov and Yablontsev and now consisted of five members, which was the originally planned number. As members of the team began leaving, the vacant slots were filled by pilots of the 1989-1990 pools, just to maintain the total number at five. With the Buran program in its death throes, this was apparently done more for bureaucratic reasons than anything else.

After Bachurin left in November 1992, his place was taken by Tokarev on 30 January 1993. Following Boroday’s departure in December 1993 Pushenko was added to the team on 6 February 1995. All this resulted in the rather bizarre situation that in the late 1980s/early 1990s the GKNII pilots were essentially split into two groups, the “career cosmonauts” based in Chkalovskiy and the “temporary cosmonauts’’ based in Akhtubinsk. Two of the earlier selected pilots, Polonskiy and Maksimenko, were never included in the Chkalovskiy team.

Just like the LII team, the GKNII team was faced with the choice in 1995 of either ceasing its existence or reassigning its pilots to other space projects. Unlike the LII team, the GKNII team was officially disbanded by an Air Force order on 30 September 1996. Two of the GKNII pilots, Kadenyuk and Tokarev, would eventually go on to fly in space, albeit in other capacities. Kadenyuk flew as a Ukrainian payload specialist on Space Shuttle mission STS-87 in 1997. Tokarev became a TsPK cosmonaut, performing a short-duration Space Shuttle mission (STS-96) to the International Space Station in 1997, and a long-duration mission aboard the ISS in 2005-2006 (for more details on the further careers of the GKNII pilots see Appendix B).

By the middle of 1980 preparations had been completed for the long-awaited inaugural test firing of a complete RD-170. Mounted on Energomash’s test-firing stand nr. 2, the engine was ignited on 25 August 1980, but shut down just 4.4 seconds later. It was only the first in a long string of setbacks for the RD-170/171. The next 15 test firings were also less than satisfactory, leading to a decision to perform the 17th test firing at a lower thrust of 600 tons. This resulted in a first successful, full-duration 150-second test firing of the RD-170 on 9 June 1981.

Subsequent test firings at the same thrust rate also produced satisfactory results, giving Energomash engineers enough confidence to move on to ground tests of the nearly identical RD-171 integrated with a Zenit first stage. These tests were carried out at the IS-102 test stand of NIIkhimmash, originally used in the 1950s for testing the first stage of the R-7 missile and later the scene of test firings of the Proton first stage and the second, third, and fourth stages of the N-1. The engine earmarked for the test (serial nr. 18) had already undergone a successful test firing at Energomash’s facilities in September 1981. Later analysis did show that a turbopump rotorblade had been damaged by particles that had somehow entered the turbopump assembly, but this was considered benign enough to press on with the test firing of the Zenit first stage on 26 June 1982. To the amazement of onlookers, the test ended in disaster near the end of its scheduled 6-second duration, when the turbopump assembly burnt through and caused a massive explosion that completely destroyed the stage and the entire test stand.

The disaster raised serious questions about the fundamental design of the RD-170/171, the more so because the test had been performed at only 600 tons of thrust rather than the nominal 740 tons. It led to the creation of an interdepartmental commission to look into the status of the RD-170 development program and consider

possible alternatives for powering the Zenit first stage and Energiya’s strap-on boosters. Headed by Valentin Likhushin, the head of Nil TP, the commission included such luminaries of the Soviet rocket industry as Arkhip Lyulka, Nikolay Kuznetsov, and also Valentin Glushko himself.

One idea, proposed by I. A. Klepikov at Energomash, was to equip each combus­tion chamber with its own, smaller turbopump assembly, transforming the RD-170 into four engines with 185 tons thrust each (hence their designation MD-185, with the “M” standing for “modular’’, because the idea was to use the engine on a variety of rockets). Actually, an order to study such an engine had already come from the Minister of General Machine Building Sergey Afanasyev as early as 11 October 1980. Wary of witnessing a repeat of the N-1 fiasco, Afanasyev had ordered to set up a complete department within Energomash to design such an engine in order to safe­guard against any major development problems with the RD-170/171. It was felt that the 2UKS experimental engine, successfully tested in 1977-1978, could serve as a prototype for the MD-185.

Another option was to use the NK-33 engines developed by the Kuznetsov design bureau (under the Ministry of the Aviation Industry) for a modified version of the N-1 rocket. Although the N-1 had been canceled before the NK-33 engines ever had a chance to fly, forty of these reusable engines had undergone an extensive series of test firings up to 1977, proving their reliability. By making small modifications to the turbopumps, Kuznetsov’s engineers had managed to uprate the NK-33’s thrust from about 170 tons to just over 200 tons, meaning that four would be sufficient to replace the RD-170. Energiya’s chief designer Boris Gubanov flew to Kuznetsov’s plant in Kuybyshev, where he was shown more than 90 such engines lying in storage.

The most radical alternative studied was to replace the Blok-A strap-ons with solid-fuel boosters. That task was assigned to NPO Iskra in Perm (chief designer Lev N. Lavrov), an organization specialized in solid-fuel motors that had already built several small solid-fuel systems for Energiya-Buran. NPO Iskra devised a plan for a 44.92 m high booster consisting of seven segments. Weighing 520 tons (460 tons of which was propellant), the booster would produce an average thrust of 1,050 tons (specific impulse 263 s) and operate for 138 seconds before separating from the core stage.

In the end, none of the three proposals was accepted. Although the MD-185 was probably the least radical alternative, research showed that it would not solve the turbopump burn-through problems as the temperature of the generator gas would be virtually the same as in the RD-170/171. A major problem with both the MD-185 and NK-33 was that they increased the total number of engines on Energiya from eight to twenty, leaving more room for failure.

One can also safely assume that Glushko had second thoughts about using the NK-33 engines. After all his efforts to erase the N-1 from history, it is hard to imagine he would have accepted using engines that had originally been built for this rocket. What’s more, in 1977 Glushko had secured a decision from the Council of Ministers to ban all work on powerful liquid-fuel rocket engines not only at Kuznetsov’s design bureau, but at any organization under the Ministry of the Aviation Industry. Understandably, Kuznetsov was not about to come to Glushko’s rescue just like that.

One of the conditions he laid down for participating in the Energiya program was that his team be officially rehabilitated after the abrupt and humiliating cancellation of its efforts several years earlier.

It was even easier to find arguments against NPO Iskra’s solid rocket motors. Aside from the safety and ecological concerns inherent in solid-fuel rockets, the Soviet Union had no experience in building solid rocket boosters of this size. More­over, they would not have been reusable and it would have been difficult to operate them in the temperature extremes of Baykonur. It would have taken an estimated 8 years to get them ready for flight.

In fact, any of the three alternative proposals would probably have delayed the first flight of Energiya by many years and would only have added to the already soaring costs of the program. In September 1982 the interdepartmental commission decided to continue test firings of improved versions of the RD-170/171 and at the same time continue research work on the MD-185. The official investigation into the June 1982 accident had concluded that it was probably the direct result of the engine being tested in a vertical position (as opposed to the near-horizontal position for the

Energomash tests). However, Energomash engineers disagreed and believed it had been caused either by aluminum particles entering the turbopump assembly from the propellant tanks or by high vibrations of the turbopump assembly.

Among the measures taken to prevent a repeat of the accident were the instal­lation of filters to prevent particles from entering the turbopump assembly and the strengthening of certain components of the turbopump. Those efforts paid off with the first successful full-duration 142-second test firing of the RD-170 at nominal thrust (740 tons) on 31 May 1983, which by many was considered a make-or-break test for the engine. In the following months, the engine performed better and better, clearing the path for another test of the RD-171 as part of a Zenit first stage. Bearing in mind the disastrous outcome of the first such test, a commission was set up to decide if it could proceed. In October 1984 the commission gave a negative recom­mendation (even KB Yuzhnoye chief Vladimir Utkin), but that was overruled by the new Minister of General Machine Building Oleg Baklanov, who had replaced Afanasyev in the spring of 1983 and proved to be a more avid supporter of the RD-170 than his predecessor. In the end, the Zenit first stage operated flawlessly in a test firing at the refurbished IS-102 test stand of NIIkhimmash on 1 December 1984, repeating that performance at the end of the same month.

Like NASA in 1977, Buran program managers considered it necessary to conduct an approach and landing test program to investigate the performance of the orbiter during the final atmospheric portion of the mission. Key objectives were to check the ability of the cosmonauts to fly Buran to a controlled landing and to demonstrate the possibility of conducting automatic landings. The Soviets referred to these tests as “Horizontal Flight Tests’’ (Gorizontalnye Lyotnye Ispytaniya or GLI).

Although the objectives of the program closely matched those of NASA’s Approach and Landing Tests (ALT) with Space Shuttle Enterprise, the Russians faced one huge obstacle. They lacked an airplane that was big enough to carry an orbiter piggyback for drop tests. NASA had used a Boeing-747 carrier plane to bring the Enterprise to the desired altitude, after which it was released so it could glide to a landing at Edwards Air Force Base in California. However, at the time the Russians didn’t have the Antonov An-225 Mriya available yet and were still relying on the VM-T Atlant. Atlant’s limited capability posed a serious problem for program managers. It was not able to lift a complete Buran orbiter and, in order to get off the ground, the orbiter had to be stripped of many of its systems, including the tail. It was clear that conducting an approach and landing test program the way NASA had done was virtually out of the question, although the possibility was considered, among other things by using the An-22 Antey aircraft.

Instead, it was decided that an orbiter would have to be built that could take off from a runway by itself. That was an immense challenge for designers since Buran, like the Space Shuttle Orbiter, was never designed to take off like a conventional airplane. Nevertheless, a modified vehicle was constructed that would meet the requirements. Officially named OK-GLI, it was described as an “analog” of Buran and would become commonly known as BTS-002 (or BTS-02), with BTS standing for “Big Transport Airplane’’ (Bolshoy Transportnyy Samolyot). It got the registration number CCCP-3501002.

First of all, nacelles were added to the aft fuselage that would house afterburner – equipped Lyulka AL-31F turbojet engines like those that were standard on Sukhoy Su-27 jet fighters [20]. This was in addition to two Lyulka AL-31 engines without afterburners on either side of the tail section which at the time were scheduled to be installed on spaceworthy orbiters as well. But, while BTS-002 had those two engines, in the end plans to install them on the “real” orbiters were dropped (see Chapter 7). The presence of engines on the BTS also afforded longer flight times (more than 30 minutes) and consequently more time to test flying characteristics than was the case with Enterprise’s Approach and Landing Tests, which lasted no longer than 5.5 minutes.

Wind tunnel tests had to be conducted to see whether or not the addition of these engines would have any influence on the vehicle’s aerodynamics, which was deter­mined as minimal. Since BTS-002 would not be subjected to the high temperatures of re-entry, no thermal protection system was needed. Instead, foam plastic tiles were used to cover the craft. The fuel tank for the turbojet engines was placed in the otherwise empty payload bay. Maximum take-off weight was 92 tons.

Another modification needed on BTS-002 was a system to retract the landing gear shortly after take-off. Also, the nose gear strut was slightly lengthened to increase its ground angle to 4°, which was required to facilitate take-off. As a result, BTS-002’s nose was considerably higher from the ground than Buran’s.

Just like Enterprise, BTS-002 had an air data system mounted on a boom extending from the nose of the vehicle (on spaceworthy vehicles this was embedded in the heat shield for protection during re-entry). The cockpit contained work stations for a commander (RM-1), co-pilot (RM-2), and flight engineer (RM-3), although the latter was never used. The pilots wore standard flight overalls and helmets and were strapped in ejection seats designated K-36L. BTS-002 had four on-board com­puters.

The presence of the jet engines and the landing gear retraction system were the main external differences between BTS-002 and the “real” Buran. The airframe configuration was similar to that of the orbiters that were destined for space. Center of gravity and other flight dynamics criteria were deemed within acceptable limits.

The BTS-002 pilots trained extensively for the missions on a wide variety of “flying laboratories” and also in the PRSO-1 and PDST simulators at NPO Molniya. All in all, during training sessions, the crews spent about 3,200 hours in the flight simulators, which given the eventual success of the flights clearly paid off [21].

In 1983 BTS-002 was transported by barge from the Tushino Machine Building Factory to Zhukovskiy, where it underwent further testing in a newly built facility at the premises of EMZ [22]. The approach and landing tests took place at the neighbor­ing Flight Research Institute. Before the flights started, the infrastructure consisting of beacons, radars, and transponders was modified to make it similar in set-up to that of the Yubileynyy field at the Baykonur cosmodrome. In late 1984, all was set for the first tests. Whereas NASA had conducted a relatively short program consisting of only five flights between August and October 1977, the Ministry of the Aviation Industry took one small step at a time [23].

As was common practice when new airplanes were tested in the Soviet Union, the flights were preceded by a number of taxi tests and take-off runs with increasing speeds. During most or all of the flights the crew flew two approach trajectories. First, they would descend to an altitude of some 15 to 20 m and then take the vehicle back to an altitude of 4,000 m for a second approach. On each flight BTS-002 was escorted by one or two airplanes. In all, four different chase planes were used during the tests: the L-39, Tu-134, Su-17, and MiG-25-SOTN.

This is an overview of all the ground runs and landing tests:

Ground run Date: 29 December 1984

Crew: Volk-Stankyavichus Duration: 5 minutes (14: 30-14: 35) (Moscow time)

During this first short taxi test, a maximum speed of between 40 and 45 km/h was reached, after which BTS-002 was subjected to a series of full-scale equipment tests.

Ground run Date: 2 August 1985

Crew: Volk-Stankyavichus Duration: 14 minutes (18: 56-19: 10)

During this second ground run the crew conducted two take-off runs down the runway. During the first one they tested the nose gear steering system at speeds of 30-40 km/h and performed braking at a speed of 100 km/h. Then they turned BTS-002 around and took it to a maximum speed of 205 km/h before deploying the drag chutes.

Ground run Date: 5 October 1985

Crew: Volk-Stankyavichus Duration: 12 minutes (15: 31-15:43)

Maximum speed 270 km/h. One of the left main gear tires blew out due to skidding during braking.

Ground run Date: 15 October 1985

Crew: Volk-Stankyavichus Duration: 31 minutes (14: 44-15: 15)

With a speed of 300 km/h, Volk and Stankyavichus almost reached the minimum take-off speed and briefly lifted the nose gear into the air.

Ground run Date: 5 November 1985

Crew: Volk-Stankyavichus Duration: 12 minutes (13: 40-13: 52)

Maximum speed during this run was 170 km/h.

GLI-1 Date: 10 November 1985

Crew: Volk-Stankyavichus Duration: 12 minutes (14: 06-14: 18)

On 10 November 1985, after taking an 1,800 m run and reaching a speed of 320 km/h, BTS-002 took off from Zhukovskiy’s runway for its first flight, during which an altitude of 1,500 m and a

speed of 480 km/h were reached [24]. The flight, primarily intended to determine the craft’s stability and handling, was a complete success, and upon their return Volk and Stankyavichus were greeted by their colleagues and ground crews in the traditional Soviet test-pilot way: by being tossed in a blanket. After that it was back to business with a debriefing by a commission of the Ministry of the Aviation Industry, headed by LII chief A. D. Mironov. Such debriefings would take place after each of the subsequent flights.

GLI-2 Date: 3 January 1986

Crew: Volk-Stankyavichus Duration: 36 minutes (14: 19-14:55)

Second “general” test flight. A speed of 520 km/h was reached while the analog climbed to an altitude of 3,000 m. As had been done on the first flight, a conventional 3 degree glideslope was used and BTS-002 was manually brought back to the runway.

Ground run Date: 26 April 1986

Crew: Levchenko-Shchukin Duration: 14 minutes (15: 17-15: 31)

The second projected Buran crew conducted a ground run in preparation for its own flights on the analog. One of the right main gear tires blew out due to skidding during braking.

GLI-3 Date: 27 May 1986

Crew: Volk-Stankyavichus Duration: 23 minutes (13: 34-13: 57)

Third “general” test flight. Altitude 4,000 m, speed 540 km/h.

GLI-4 Date: 11 June 1986

Crew: Volk-Stankyavichus Duration: 22 minutes (07: 42-08: 04)

During the fourth and final “general” test flight an altitude of 4,000 m and speed of 530 km/h were reached. It was also the first flight during which the standard landing mode with a steep glideslope of about 20 degrees was worked out. All three channels needed to fly the orbiter towards landing in an automatic mode were tested sequentially. Leveling out began at approximately 500m, so the final angle of approach was only two to three degrees.

GLI-5 Date: 20 June 1986

Crew: Levchenko-Shchukin Duration: 25 minutes (07: 40-08: 05)

On the fifth flight, the crew took things one step further by simultaneously switching on all three channels needed for an automatic landing.

GLI-6 Date: 28 June 1986

Crew: Levchenko-Shchukin Duration: 23 minutes (09: 30-09: 53)

All three channels were used to make BTS-002 glide automatically to an altitude of 100 m. At that altitude, Levchenko took over the controls for final approach and landing.

GLI-7 Date: 10 December 1986

Crew: Volk-Stankyavichus Duration: 24 minutes (13: 07-13: 31)

The automatic landing system controlled BTS-002 until the final second before touchdown. At that point, Volk switched the system off and performed a manual landing.

GLI-8 Date: 23 December 1986

Crew: Volk-Stankyavichus Duration: 17 minutes (12:43-13: 00)

GLI-8 saw the first landing considered to have been automatic, although the system was switched off once the main gear had touched down. Roll-out was controlled by the pilots.

GLI-9 Date: 29 December 1986

Crew: Levchenko-Shchukin Duration: 17 minutes (12:57-13: 14)

BTS-002’s complete approach and landing took place in automatic mode from an altitude of 4,000 m until coming to a complete stop. The only thing that was still done manually was lowering the nose gear to the runway.

GLI-10 Date: 16 February 1987

Crew: Volk-Stankyavichus Duration: 28 minutes (13: 30-13: 58)

First fully automatic landing, in which the pilots didn’t undertake any action from the initiation of the approach from 4,000 m until coming to a full stop on the runway.

GLI-12 Date: 25 June 1987

Crew: Stankyavichus-Volk Duration: 19 minutes (14: 34-14: 53)

Approach and landing took place in automatic mode.

GLI-13 Date: 5 October 1987

Crew: Shchukin-Volk Duration: 21 minutes (13: 50-14: 11)

Approach and landing took place in automatic mode.

Air Force test pilots Ivan Bachurin and Aleksey Boroday were scheduled to take BTS-002 to the skies for GLI-14. But, after starting up the turbojet engines, warning lights indicated that a problem had been detected. After consultation with the test director, they decided to taxi to the runway and start a take-off run. If the engines indeed weren’t functioning the way they should after they had been throttled up, the flight would be aborted. When it turned out that the warning lights were still on, the test director scrubbed the flight and ordered Bachurin and Boroday to return to the platform. This was the only scrub in the program after the vehicle’s engines had been started up.

After the problem had been solved, the flight got a new designation and the crew got another opportunity.

GLI-14B Date: 15 October 1987

Crew: Bachurin-Boroday Duration: 19 minutes (08: 12-08: 31)

Approach and landing took place in automatic mode.

After the unmanned spaceflight of Buran, Ivan Bachurin wrote the following report on GLI-14B as part of a paper on the GLI program:

“We were informed about the upcoming flight a week in advance. We prepared for the tasks we were to perform by flying the mission profile on the simulator. After that, we made the plotting charts, divided the various tasks between the two crew members, etc.

On the eve of the flight, we attended a session of the commission that determined the readiness of the aircraft, the ground facilities and infrastructure, and the crew. The reports were all fairly straightforward and only a few ques­tions were asked. The ground facilities and the aircraft were ready, and the crew was fully prepared to perform their duties. The chairman of the commission then asked: ‘Is there a need for the commander to rehearse the flight on the Tu – 154LL?’ ‘Yes, there is.’ ‘Is the plane ready?’ ‘Yes, it is.’ ‘Then you will perform that flight after the meeting.’

We performed the rehearsal flight on the flying laboratory without any problems, completed the training in the cockpit of the analog and performed a start-up of the engines for training purposes.

We spent the night at the airfield since the flight was scheduled to take place early in the morning. We didn’t talk about the upcoming flight: we had had good discussions about that subject for a week.

In the morning, we looked out the window to check the conditions. They had forecast that the wind would pick up in strength. We washed and shaved, had breakfast and underwent a medical check-up. After that, we sat and waited for the order to go. In my mind, I went through the whole upcoming flight again. Then, after a few minutes, came the signal: ‘Everything is ready. The bus is on its way to pick you up.’ ‘OK, we’re on schedule.’ We then took our gear and left for the bus, and I felt that usual pleasant feeling of being ready to perform the flight.

On our way over to the operations building, we passed ‘Number Two’ as we called the analog amongst ourselves. Inside the building, everybody was busy with his tasks. We walked into one of the dressing rooms, and weren’t disturbed by anybody for the next 15 minutes. Then the order came: ‘The crew is to take its positions.’

We went to the steps leading up to the vehicle, where a single cameraman was recording all our activities. In the small room at the end of the steps experts helped us don our personal parachute harnesses, after which we crawled through the side hatch into the cockpit and took our seats.

By then two planes, one to escort us and the other to shoot video, reported that they were ready. We could begin.

While constantly consulting the mechanic and the Flight Experiment Control Post (FECP) we prepared and started the engines, and turned on all the ship’s systems. The engineers at the FECP supervised the commands we gave to the on­board systems and could step in at any time to assist us. In the meantime [the two] planes took off.

We disconnected the external power sources and started to taxi out to the runway. The aircraft handled well, braking was very effective. I tried to remem­ber what our altitude from the ground would be, which was unusually high.

On the runway we warmed up the engines. By then, the [two] planes took their positions in the air so that at take-off they would be flying beside us. Then, at the command of the escort plane’s pilot, we put our engines in the take-off mode, did a final check of the parameters for the engines and other systems, and began taking off. The run along the runway was steady and easily controllable. Exactly at the right speed and almost immediately after I deflected the stick, the nose wheel lifted from the ground. Then we were airborne. I reduced the deflec­tion of the stick and the plane maintained its planned climb angle.

The co-pilot in the right seat, Aleksey Boroday, reported: ‘I’m pulling up the landing gear. The temperatures of engines two and three are gradually reaching their pre-set limits.’ The commander says: ‘Do not exceed.’ The co-pilot replies: ‘The temperature is now constant.’ It is good that the pilot has the capability to

take part in the control of the ship, and is constantly ready to assist the com­mander. ‘Wheels up.’

I found that as far as stability and controllability were concerned the real ship differed little from the simulator. The aircraft ‘was tightly in our hands’.

‘You’re right on schedule,’ we were told by the pilot of the escort plane. I looked around and saw the fighter not far from us, together with a Tu-134 that was shooting video. I warned the pilot of the escort plane that I was about to carry out the standard maneuvers used in these test flights for defining flying characteristics. Also, I checked the air brake.

The altitude was the predetermined one and I turned to get to our entry point. The FECP navigation officer gave us our exact position. We reached the entry point. I switched the engines to idle and activated the automatic control unit. Very eagerly, perhaps too eagerly, ‘Number Two’ executed the desired maneuver to begin the planned descent trajectory. We kept an eye on the steep descent trajectory, the performance of the on-board systems, and the air brake. The speed was what had been calculated and the plane quickly descended to the ground. Then, the plane began to level off and ‘Number Two’ smoothly decreased its speed. The landing gear was lowered and my hand was near the plane’s control stick. The fact that we were flying in automatic mode didn’t mean that we were sitting idle. The Tu-154LL would have been ‘scattered all over the ground’ had it not been for the intervention of Aleksandr Shchukin when during one of the automatic flights the plane dived right to the ground!

The altitude decreased to 200 meters, then 100, then 50. At that point, the plane was on glideslope. ‘Thirty meters… twenty meters’, read the co-pilot. ‘Let’s go up again’. I turned off the automatic control unit and increased the engine thrust. The co-pilot closed the air brake and turned off the landing mode.

The second pass was carried out in the same sequence: in automatic mode up to full stop on the runway. ‘Altitude ten… five… three, two, one meter… contact!’, reported the pilot of the escort plane. ‘Drag chute deployed’, the co­pilot confirmed.

Roll-out was steady and we had no more than a two-meter deviation from the runway’s centerline. The fighter that had served as the escort plane finished its activities with a beautiful zoom climb.

Lowering the nose wheel was smooth and the braking on the wheels was effective. Jettisoning of the parachute occurred at the right speed. ‘Number Two’ rolled to a stop. We taxied in for parking and after turning off the engines we left our seats and disembarked via the steps to the platform. Technicians and en­gineers came to the plane, and I looked with gratitude to those who had spent many hours the previous night preparing ‘Number Two’ for flight.

Finally, we gave our report and the flight was analysed. At the end of that debriefing the test director announced the date for the next flight’’ [25].

Subsequent flights simulated situations where a returning orbiter would not be at the ideal point when the final approach maneuvers were initiated. For this, the crew

would bring BTS-002 to different altitudes, or fly at speeds or in directions that differed from the calculated flight paths. In all cases, the control system corrected the deviations and brought the vehicle safely back to the runway.

GLI-19 Date: 12 March 1988

Crew: Boroday-Bachurin Duration: 21 minutes

Approach and landing took place in automatic mode.

GLI-20 Date: 23 March 1988

Crew: Boroday-Bachurin Duration: 21 minutes

Approach and landing took place in automatic mode.

GLI-21 Date: 28 March 1988

Crew: Boroday-Bachurin Duration: 22 minutes

Approach and landing took place in automatic mode.

GLI-22 Date: 2 April 1988

Crew: Stankyavichus-Shchukin Duration: 20 minutes

Approach and landing took place in automatic mode.

GLI-23 Date: 8 April 1988

Crew: Shchukin-Stankyavichus Duration: 21 minutes

Approach and landing took place in automatic mode.

GLI-24 Date: 15 April 1988

Crew: Volk-Stankyavichus Duration: 19 minutes

Final flight in the GLI program. Approach and landing took place in automatic mode.

With this, the first phase of the approach and landing tests was completed, but plans were drawn up for follow-on test flights. In March 1988 the Council of Chief Designers ordered the possibility of including NPO Energiya engineers in future BTS-002 crews to be studied, but it appears this option was not seriously considered. A later plan called for 13 more flights with pilots from both LII and GKNII. After the deaths of Levchenko and Shchukin in August 1988, LII proposed two crews consisting of Volk-Tolboyev and Stankyavichus-Zabolotskiy. Those two teams would fly the bulk of the missions, while the GKNII pilots would get just three or four flights [26].

In late 1989 Volk declared that he was still expecting to participate in the new series of BTS flights [27]. A first ground run to kick off the new phase was conducted by Rimantas Stankyavichus and Viktor Zabolotskiy, who had already been training for a possible Soyuz “warm-up flight”. During the test BTS-002 blew both tires of its right main landing gear.

Ground run Date: 28 December 1989

Crew: Stankyavichus-Zabolotskiy Duration: Unknown

Many years later Igor Volk would explain that this had been “an attempt [by Lozino-Lozinskiy] to renew the program. But, unfortunately, after the program had been stopped for a year and a half, it appeared they needed to correct many things and they stopped again” [28]. One source claims there were two more take-off runs on 23 November and 6 December 1990 just to keep BTS-002 in working order [29]. However, BTS-002 would never fly again. Still, all 24 flights had taken place without encountering any significant problems and played an important role in paving the way for Buran’s first orbital missions [30].

Fueling of Energiya was completed three hours before launch and that of the LOX tanks of Buran’s ODU propulsion system at T — 2h45m. A critical point came at T — 10 minutes, when the countdown switched to automatic control. Controllers breathed a sigh of relief when the balky azimuthal alignment plate responsible for the 29 October scrub retracted as planned at T — 51 seconds. With sound suppression water gushing onto the pad, the four RD-0120 engines of the Energiya 1L rocket roared to life at T — 9.9 seconds and smoothly built up thrust, clearing the way for ignition of the four strap-on boosters at T — 3.7 seconds. With all engines at full thrust and no problems detected, Energiya-Buran slowly lifted off the pad exactly as planned at 6: 00.00 Moscow time. It was a highly emotional moment for the thousands of people who had dedicated many years of their lives to this program ever since its approval in February 1976, although the atmosphere in the nearby control bunker was said to be business-like as all eyes were focused on the perform­ance of the rocket and orbiter.

As it cleared the tower, the stack performed a 28.7° roll maneuver to place it in the proper position for ascent. For onlookers the launch proved to be rather anticli­mactic. Just seconds after clearing the launch tower, Energiya-Buran disappeared into the low cloud deck. “What a pity for the photographers,” Pravda wrote the following day. “Standing out there freezing in the steppes all night and then every­thing is over in the blink of an eye” [51].

The only persons to maintain visual contact with the vehicle after that were the crews of an An-26 weather reconnaissance plane and the MiG-25 SOTN chase plane. The task of the chase plane during launch was not only to shoot video of the stack, but also to accompany Buran to the runway in the event of a return-to-launch-site abort. Behind the controls of the chase plane, which had taken off ten minutes before launch, was LII pilot Magomed Tolboyev, accompanied by cameraman Sergey Zhadovskiy. “It’s on its way! It’s going!” Tolboyev enthusiastically radioed to the ground as the stack broke through the clouds. Somewhat later he called out: “Engine operating mode changing.’’ He was referring to a reduction in thrust of both the core stage’s RD-0120 engines (between T + 30s and T + 1m11s) and the strap-on boosters’ RD-170 engines (between T + 39s and T + 1m15s) as the rocket and orbiter passed through the phase of maximum aerodynamic pressure.

At T + 2m23.95s the four strap-ons shut down their RD-170 engines and at T + 2m25.85s separated in pairs from the core stage. The separation was clearly visible from the MiG-25, with Tolboyev reporting:

“The strap-ons have separated! They’re on their way back to the ground…

Great. We can see them falling together, in parallel.’’

Not long after separation from the rocket each pair of boosters split in two, with all four now headed back to Earth individually. The boosters were not equipped with parachute systems for this mission and crashed into the steppes some 420 km from the launch pad about 7 minutes after separation.

Not long after booster separation the MiG-25 lost sight of the stack as it moved further downrange and eventually disappeared behind the horizon. All eyes were now focused on the telemetry being received from Soviet tracking stations and relayed to TsUP near Moscow. About 3 minutes into the launch, Buran reached the point where it could no longer return to the Baykonur cosmodrome for an emergency landing. As the stack sped further towards orbit, a camera installed behind one of Buran’s cockpit windows began sending back images of the Earth. At T + 6m53s the core stage’s RD-0120 engines began slowly throttling down and eventually shut down at T + 7m47.8s. Energiya’s job done, members of the rocket team quietly shook hands beneath the table, celebrating the second successful flight of the launch vehicle in as many attempts. Now it was up to the orbiter team to finish the job. Buran was now in a theoretical —11.2 x 154.2 km orbit and, if nothing were done, would re-enter shortly afterwards.

Separation of the orbiter from the core stage took place at T + 8m02.8s at an altitude of roughly 150 km. The core stage was scheduled to re-enter the atmosphere, with fragments coming down in the Pacific some 19,500 km from the launch point. After firing its thrusters to move to a safe distance from the core stage, Buran now positioned itself for a critical burn of one of its two DOM orbital maneuvering engines to impart the 66.7 m/s of additional velocity needed to reach orbit. The burn, monitored by the easternmost Soviet ground stations as Buran headed for the Soviet – Chinese border, got underway at T + 11m28s and lasted 67 seconds.

About thirty-five minutes later, at T + 46m07s, as Buran came within range of the tracking ships Dobrovolskiy and Nedelin in the South Pacific, one of the DOM engines burned for another 40 seconds (delta-V of 41.7m/s) to place the orbiter into its final 247 x 255 km orbit. Inclination was 51.6°, the same as that of the Mir space station, but the two were in different orbital planes. Since this was a conservative two – orbit test flight, there was no need for Buran to further increase its orbital altitude.

Although Soviet media did not carry the launch live, both Radio Moscow World Service and the Soviet domestic Mayak radio station reported the launch at the very beginning of their 3: 00 gmt newscasts. The World Service even optimistically said Buran had been placed into orbit, although orbital insertion was still at least ten minutes away. At 4: 10 gmt Mayak broadcast a recorded live report of the launch from its reporters both at Baykonur and in Mission Control in Kaliningrad. Moscow television showed the first footage of the launch 1.5 hours after blast-off. The TASS news agency issued the following official statement on the launch:

“On 15 November 1988 at 6.00 Moscow Time the Soviet Union launched the

universal rocket space transportation system Energiya with the reusable ship

Buran. At 6.47 the orbital ship went into the planned orbit. The test program envisages a two-orbit flight of the orbital ship around the Earth and a landing in automatic mode at the Baykonur cosmodrome at 9.25 Moscow time.”

After returning from its mission on 15 November 1988, the 1K orbiter was sent back to the MIK OK orbiter-processing facility for post-flight inspections. Those were interrupted in early May 1989 for test flights with the An-225 Mriya carrier aircraft, staged from the Yubileynyy runway. This was in preparation for the long flight to the Paris Air Show the following month (see Chapter 4). In late June 1989 Mriya returned Buran back to Baykonur. The pair made one last demonstration flight over

Baykonur on 12 April 1991 as part of an air parade to mark the 30th anniversary of the flight of Yuriy Gagarin. Later that year Soviet space officials discussed the possibility of bringing Mriya and Buran to the International Aerospace Convention in Huntsville, Alabama in July 1992, but those plans were never realized [45].

As it turned out, the demonstration flight in April 1991 had been the last time that 1K ever took to the skies. In early 1990 Western reports claimed vehicle 1K had been retired from flight status. As it had been built without a life support system, full avionics systems, and a fuel cell electrical system, it was considered too costly and difficult to modify the vehicle for a future useful unmanned or manned flight [46]. Another reason given for the grounding of vehicle 1K was that design changes had been introduced in the newer airframes under construction at the Tushino Machine Building Factory that would be too expensive to incorporate into the older vehicle. Moreover, the Soviet policy apparently was that each airframe had a lifetime of 10 years, no matter how many flights it made. With construction of 1K having started in 1983, the ship was nearing the end of its warranty [47]. However, given the astro­nomical cost of building an orbiter, it is hard to imagine that the Russians would have strictly adhered to this policy. In fact, vehicle 1K still figured prominently in the Mir – 2 assembly plans outlined in late 1991. The reported retirement of the first flight vehicle may have had more to do with the increasingly bleak prospects for the program than anything else.

For years, Buran languished in the thermal protection system bay of the MIK OK, only to be shown to occasional visitors. In 1994 the idea arose to save it from oblivion by mating it with an Energiya rocket for permanent display at the MIK RN Energiya assembly building. Since it was considered that the stack should resemble the real thing as much as possible, the intention was to attach Buran to flightworthy Energiya hardware mothballed at the MIK RN—namely, the core stage of vehicle 2L and the strap-on boosters originally earmarked for vehicle 3L. However, in the mid – 1990s a decision was made to remove the RD-170 engines from the strap-on boosters for vehicles 3L to 6L and ship them back to Energomash to be modified for use on Zenit-3SL rockets being built under the Sea Launch program. Finally, Buran was moved to high bay 4 of the MIK RN in July 1998 and assembled the following month with a non-flight rated Energiya consisting of the core stage of vehicle 5S1 and the strap-ons of vehicle 4M-KS [48].

As if its fate wasn’t sad enough, Russia’s only flown shuttle was reduced to scrap when the roof covering the three high bays of the MIK RN collapsed on 12 May 2002. The accident claimed the lives of seven men conducting repairs on the leaky roof. It was blamed on a combination of factors that had made the roof 1.5 times heavier than specified. First, the roof insulation material used during the construction of the MIK back in the 1960s was heavier than it should have been. Second, the roof had absorbed several days’ worth of heavy rains, and, third, more than 10 tons of new roofing material had accumulated on the building in preparation for the repairs. The collapse destroyed not only orbiter 1K, but also the other Energiya hardware remain-

ing in the MIK: three core stages and two Blok-Ya launch pad adapters in high bay 3, eight strap-on boosters in high bay 4, and another eight strap-ons in high bay 5 [49].

Orbiter 2K (“Buran-2”)

The second spaceworthy orbiter 2K (sometimes called “Buran-2”, airframe nr. 1.02) arrived at Baykonur atop a VM-T carrier aircraft on 23 March 1988. Because of the relatively limited lifting capability of the VM-T, vehicle 2K arrived at the cosmo­drome underweight and in a relatively “raw” state, with a lot of work still remaining to be done before its first flight. The Mir/Soyuz docking mission planned for 2K was

much more challenging than the conservative two-orbit test flight of vehicle IK. Because of that the ship needed to be outfitted with systems that had not been on the original orbiter, such as a partially operational life support system, fuel cells, a fully operational payload bay door actuation system, a docking mechanism, and a remote manipulator arm. The vehicle was also equipped with a single ejection seat and several non-ejection seats.

On 16 May 1991 vehicle 2K, attached to the 4M core stage and strap-ons, was rolled out to Energiya-Buran pad 37 for two weeks of tests. The roll-out was witnessed by the crew of Soyuz TM-12 (Artsebarskiy, Krikalyov, Sharman), who were making final preparations for their mission. One obvious external sign that the ship wasn’t quite ready for flight yet was that many of its heat-resistant tiles were still missing. Among the work done at the pad were load tests of the fuel cells and orbiter evacuation exercises. On 30 May the stack trundled back to the MIK RN to be prepared for three days of tests at the Dynamic Test Stand (7 June-10 June 1991). After that it once again returned to the MIK RN, where vehicle 2K was detached from the core stage and returned to the MIK OK [50].

Speaking at the International Astronautical Federation Congress in Montreal in October 1991, Yuriy Semyonov told reporters that the Energiya rocket for the Buran – 2 mission had been placed on the launch pad in preparation for a 10-15 second static test firing of its main engines, and there is some evidence that Energiya 3L did undergo such a test that year [51].

By the time the Energiya-Buran program was canceled, the 2K orbiter was said to be 95-97 percent ready. The vehicle was later moved from the MIK OK to the defunct Assembly and Fueling Facility (MZK), where it still resides today.

The 11K55 was a lighter version of Zenit conceived jointly by KB Yuzhnoye and the Omsk-based PO Polyot in 1976. In its original design it had a modified Zenit first stage with a smaller propellant load and a two-chamber version of the RD-170. The newly developed second stage would be powered by a cluster of three LOX/kerosene 11D58M engines of NPO Energiya’s Blok-DM upper stage. With a launch mass of 210 tons, the rocket had a payload capacity of roughly 5 tons. The 11K55 was seen as an environmentally clean replacement for the Kosmos-3M and Tsiklon launch vehicles, rockets with storable propellants built at Polyot and Yuzhnoye, respectively. Launches were to take place from Plesetsk and Kapustin Yar. Other engines con­sidered for use on the 11K55 in the late 1980s/early 1990s were a cluster of three or four RD-120K engines on the first stage and two different re-ignitable LOX/kerosene engines for the second stage, the RD-133 and RD-134, both with a vacuum thrust of 35 tons. The 11K55 is known to have been the subject of a government decree in 1986 [69].

11K37

In 1976 KB Yuzhnoye also began looking at heavier versions of Zenit. One idea was to build a 5.4m diameter first stage with two RD-171 engines, but this was deemed unrealistic because it required new manufacturing techniques and untested transpor­tation methods by road, water, or air. Instead, planners concentrated on rockets with

two, three, or four Zenit first stages clustered together, capable of putting between about 30 and 60 tons into low orbit. The common designator for these boosters was 11K37.

The most thoroughly studied version was the one with three Zenit first stages. Mounted above that would have been a second stage with a 214-ton thrust single­chamber version of the RD-170 engine known as RD-141 as well as an RD-8 vernier engine. A later idea was to equip the stage with three 90-ton thrust RD-142 engines and several verniers. The RD-142 was apparently an improved version of the RD-120 engine used in the second stage of the 11K77. With the latter second stage, the 11K37 would have been capable of putting 40 tons into low orbit, 35 tons into polar orbit, and about 5 tons into geostationary orbit. Upper stages studied by Yuzhnoye for the 11K37 were an interorbital space tug originally developed for deployment from Buran as well as the Vikhr cryogenic upper stage.

As mentioned earlier, the 11K37 was proposed by KB Yuzhnoye in a com­petition started in 1984 to develop boosters in the 30-60 ton range, with the other candidates being Groza and an upgraded Proton rocket. A major disadvantage of the 11K37 was that it required the construction of a new launch facility. Therefore, the Ministry of General Machine Building recommended in the late 1980s to make the rocket compatible with Energiya’s UKSS launch pad at Baykonur. When a new competition was launched in the early 1990s to develop rockets in the 20-40 ton payload range, the 11K37 was still in the running, but eventually lost out to Energiya – M in 1991 [70].