Category Energiya-Buran

According to original flight plans drawn up in the 1970s, Energiya was to begin its test flights in 1983 with two suborbital missions carrying full-scale Buran mock-ups, followed in 1984 by the first launch of an unmanned flightworthy orbiter [10]. By the early 1980s those timelines had changed significantly, as had the flight plans them­selves. The idea was now to launch an unmanned Buran into orbit on the first mission of Energiya (rocket 1L) following the completion of fueling tests with the 4M core stage and pad test firings of the 5S and 6S vehicles.

The original plan for 17 pad test firings lasting a total of 3,700 seconds was quickly laid to rest. Satisfied with the results of the 5S test firing on 25 April 1986, the MVKS decided on 5 May to significantly curtail the test-firing program and conduct just one more test firing with the 6S vehicle to reach an accumulated pad burn time of 423 seconds prior to the maiden launch of Energiya. The plan was to turn the remaining 30-second test into a combined test firing of the four RD-0120 core stage engines and the four RD-170 strap-on booster engines, something which would also have been the culmination of the original test-firing program. Consideration was also given to strapping the OK-ML1 Buran mock-up to the core stage for that test.

However, as these events unfolded, an alternative proposal from Energiya chief designer Boris Gubanov had been steadily gaining ground. That was to skip test firings of the 6S vehicle altogether and turn it into a flightworthy rocket for a test mission that would precede the flight of Energiya 1L with the Buran orbiter. In a way, it was a return to the “test-as-you-fly” philosophy so common in other Soviet space projects. Gubanov’s main argument was that if one of the test firings ended in a cataclysmic explosion, it would take two to three years to rebuild the unique test stand. Not only was the UKSS later supposed to become a launch pad, it would also continue to serve as a test stand for core stages and strap-on boosters to be flown on operational Energiya missions.

The risk of an accident would be even higher if the strap-on boosters were going to be involved in the tests as well. Rather than test-fire the rocket on the ground, Gubanov argued, it would simply be test-fired in flight. The minimum mission objective would be to fly safely for at least 30 seconds, allowing the rocket to reach a safe distance from the test stand. This would achieve the same goal as a combined 30-second ground-based test firing of the core stage and strap-ons, without running the risk of wiping out the UKSS.

The idea originated in early 1984, but it would take Gubanov almost two years to get it accepted. Gubanov made his first overture to the highest authorities in early 1985, putting forward the idea to Grigoriy V. Romanov, who as the Central Com­mittee Secretary for Defense Matters was the highest political figure in charge of the space program. However, Romanov was not convinced, electing instead to divert more resources and personnel to the space station program with the goal oflaunching the Mir core module by the next Party Congress in February 1986. The proposal initially also met with stiff opposition from NPO Energiya general designer Valentin Glushko, who at one point even said that “one wouldn’t come up with such an idea even when drunk.’’ Also opposed to the plan was launch pad chief designer Vladimir Barmin, whose organization (KBOM) would now have to turn the UKSS into a launch pad much earlier than expected. Also favoring a full-scale ground-based test firing of both the core stage and the strap-on boosters was the military community.

However, as the months progressed, events gradually turned to Gubanov’s favor. In July 1985 Romanov, once considered a leading candidate to become the next General Secretary of the Communist Party, was removed from the Politburo and from his post as Secretary for Defense Matters as part of a Party management shake-up following the election of Mikhail Gorbachov as General Secretary in March of that year. By the end of the year Gubanov had garnered support from Minister of General Machine Building Oleg Baklanov (also the head of the MVKS), who in turn convinced his ally Glushko. On 2 January 1986 Baklanov flew to the cosmodrome with a large number of leading space officials, giving them the order not to return home until an Energiya had been launched.

Long before getting the needed political support, Gubanov had secretly been making arrangements to convert the 6S core stage into a flight vehicle called 6SL (“L” standing for “flight”). He had already asked the people of the NPO Energiya Volga Branch to study this possibility during a visit to Kuybyshev in November 1984. An official industry order followed on 16 August 1985 and allowed engineers to “cannibalize” parts of the first flight-rated rocket (1L) to speed up launch prepara­tions. As a result, all elements of the core stage were in place at Baykonur by the beginning of 1986.

A key argument in getting approval for the 6SL launch was that Buran was suffering more and more delays, further pushing back the launch of Energiya 1L. An early demonstration launch of the 6SL vehicle would not only be a boost to the team, but could also help convince the country’s political leadership of the program’s feasibility. With a new wind beginning to blow through Soviet politics in the mid – 1980s, the Energiya-Buran program was finding itself on increasingly shaky ground and was in dire need of a major success. Somehow, Gubanov’s original argument for the launch—namely, to reduce the risk of a catastrophic explosion on the UKSS— had moved to the background and a 30-second combined static test firing of the 6SL core stage and strap-ons remained on the agenda even after the successful test firing of 5S in April 1986. The Military Industrial Commission set up an independent commission headed by Konstantin V. Frolov, the Vice-President of the Academy of Sciences, to look into the need for additional test firings, but this failed to give a clear-cut recommendation. However, a continuing string of successful Zenit launches and test firings of Blok-A and Zenit first stages at Nllkhimmash gradually made the test firing redundant. Energiya was ready to fly [11].

The decision to fly a two-orbit rather than a three-day mission allowed the Russians to significantly reduce the number of on-board systems and thereby move up the launch date. Apart from requiring less sophisticated software, the shorter flight obviated the need for installing such systems as fuel cells, a payload bay door opening mechanism, payload bay door radiators, etc. The only objective of the flight was to see if Buran could safely reach orbit and return back to Earth. With no crew on board, few of the life support systems needed to support humans were carried. For instance, Buran had a 90 percent nitrogen/10 percent oxygen atmosphere to minimize the risk of fire.

Original plans called for the space-rated orbiters to be equipped with two Lyulka AL-31 turbojet engines to provide flight path modification capability during the return to Earth. For this purpose Buran had two niches on either side of the vertical stabilizer to house the engine pods. However, in late 1987/early 1988 a decision was made not to install the engines, fill the niches with panels, and cover them with ATM-19PKP flexible thermal insulation.

There is conflicting information on the reasons for this decision. One source claims the atmospheric landing tests performed with the full-scale BTS-002 vehicle had shown that control was sufficient without these engines [32]. Another says the engines were not ready for the first flight. Although they had been flown on the BTS – 002, they had never been ignited in flight, nor had the thermal protection covers for the engine inlet and outlet been tested. On top of that, there were mass-related issues that needed to be addressed before the engines were flown. Not only did the engines weigh about 400 kg each, they also required support systems such as a kerosene tank (probably to be placed in the mid fuselage under the payload bay), fire suppression systems, etc. However, once those issues had been resolved, the engines might well have flown on future missions [33]. One may also speculate that the presence of the engines would have unnecessarily complicated the automatic flight program for the maiden mission. Interestingly, the throttle lever for the AL-31 engines was not removed from Buran’s cockpit for the first flight. The removal of the AL-31 engines slightly changed the vehicle’s center of gravity and placed higher aerodynamic loads

on the vertical stabilizer. Therefore, additional wind tunnel tests were run to make sure that the absence of the engines posed no unexpected problems.

Buran’s cargo bay was not empty during the first flight. Sitting in the middle of the cargo bay was a pressurized module known as Unit for Additional Instruments (BDP for Blok Dopolnitelnykh Priborov) or 37KB. BDP performed a role similar to

the Development Flight Instrumentation (DFI) on the orbital test flights of the US Space Shuttle. It was stowed full with instrumentation to record about 6,000 param­eters during the flight and also carried support equipment such as batteries to compensate for the absence of fuel cells on Buran’s maiden mission.

Its design was based on a series of modules (37K) originally planned for the Mir space station, only one of which (Kvant or 37KE) was eventually flown. On 19 April 1982 the KB Salyut design bureau (then a branch of NPO Energiya) received an order to develop a series of such modules for Buran that would carry out a variety of functions. Built at the Khrunichev factory, the first such module (serial nr. 37070) was shipped to Baykonur in February 1986 to be flown on the maiden mission of Buran. After having been tested in the Proton area of the cosmodrome, it was transported to the MIK OK orbiter-processing facility for installation into Buran. Weighing 7,150kg, it was 4.1m wide, 5.1m long, and had an internal volume of 37m3. The ultimate plan was to turn these modules into small scientific laboratories that could either remain in the cargo bay of Buran (like Spacelab) or be temporarily attached to space stations (see Chapter 8) [34].

Despite all the criticism, preparations continued at Baykonur for future Buran missions. In the summer of 1990 the OK-MT full-scale test orbiter spent a month on pad 37 (6 July-7 August) for crew boarding and evacuation exercises and also for tests in which the fuel cells were loaded with liquid oxygen and liquid hydrogen.

By the first half of 1991 more than two years had elapsed since the first flight, making many wonder if a second flight was going to take place at all. Space officials kept stressing that the 2K1 mission to Mir was still on and would be flown sometime in 1992. One glimmer of hope was a test roll-out of the 2K orbiter to the launch pad in May 1991.

However, it wasn’t long before Buran’s future was further thrown into doubt by events that shook the very foundations of the Soviet Union. On 19 August 1991 tanks rolled into Moscow as a group of Communist Party hardliners calling themselves the State Emergency Committee attempted to take control of the country while Gorbachov was vacationing in the Crimea. The coup was timed to prevent the signing of a new Union Treaty which would have fundamentally recast the relationship between the center and the republics in favor of the latter. Although the putsch collapsed in only three days, it accelerated the events that would lead to the dis­integration of the USSR at the end of the year. Adding to the growing unpopularity of the space program was the fact that one of the coup plotters had been Oleg Baklanov, who had been a strong supporter of the Energiya-Buran program in particular.

In the wake of the failed coup the Russian government took over the union government, ministry by ministry. In the autumn of 1991 the Ministry of General Machine Building was dissolved. The rocket and space enterprises located on Russian territory were transferred to the Russian Ministry of the Industry. Many of the enterprises were expected to merge into specialized conglomerates that would be

subordinate to an organization called Rosobshchemash. Established in October 1991 on the vestiges of the Ministry of General Machine Building, it would act as a middleman between the Russian government and other nations for space and defense project orders. It was headed by outgoing MOM minister Oleg Shishkin, with Yuriy Koptev acting as his deputy for space matters. However, several leading companies, including NPO Energiya, refused to join Rosobshchemash. As Koptev later recalled, the organization was ineffective in bringing together the Russian space industry. In December 1991 leading space officials requested the government to set up a Russian Space Agency, in response to which a special commission was created led by Yegor Gaydar, the Minister of Economy and Finance [14].

The committee’s findings were presented to President Boris Yeltsin during a key meeting at the Kremlin on 18 February 1992. It was attended among others by Yuriy Semyonov, Gleb Lozino-Lozinskiy, TsNIIMash director Vladimir Utkin, Vice-President of the Academy of Sciences Yevgeniy Velikhov and Koptev, who had been Gaydar’s deputy in the committee and was the leading candidate to head the new agency. While the formation of the agency topped the agenda, the meeting also addressed the future of specific programs. Opening the meeting, Yeltsin spoke out against the continuation of the Energiya-Buran program. Semyonov countered the President by saying that its cancellation would be a repeat of the flawed decision to terminate the N-l program in the 1970s and would deal an irreparable blow to the country’s scientific, technical, military, and industrial potential. Semyonov was sup­ported by Koptev and Utkin, while Velikhov echoed Yeltsin’s sentiments, calling for an immediate shutdown of the program. The official minutes of the meeting said the future of the Energiya-Buran program would require further analysis, but according to the official history of NPO Energiya “all present at the meeting felt that the fate of the program had been sealed.’’ On 25 February 1992 Yeltsin issued an edict approv­ing the establishment of the Russian Space Agency (RKA) [15].

After the failed launch of the Skif-DM/Polyus payload by Energiya 6SL on 15 May 1987 (see Chapter 6), KB Salyut continued work on the Skif project, albeit at a slow pace. Original plans to launch Skif-D1 (without a laser payload) and Skif-D2 (with a laser payload) in 1987 and 1988 soon turned out to be unattainable. Several major components of Skif-D1 (both for the FSB and the Payload Module) were finished at the Khrunichev factory by early 1987, but serious problems with the development of the vehicle’s acquisition, tracking, and pointing system delayed the final assembly of the spacecraft. That, combined with the declining support from the Gorbachov administration for Star Wars programs, led to the suspension of all Skif-related work at KB Salyut and the Khrunichev factory in September 1987.

While Skif was supposed to use laser-type weapons to destroy low-orbiting satellites, KB Salyut concurrently also developed the Kaskad system, armed with conventional missiles to destroy satellites in medium and geostationary orbits. Vir­

tually nothing has been revealed about this project, but it was almost certainly also supposed to be launched by Energiya [59].

The Universal Test Stand and Launch Pad, used for Energiya fueling tests, test firings, and also for the first launch of Energiya in May 1987, is in relatively good condition. Also run by NIIkhimmash, it is being maintained by a 110-man strong team. Key systems such as the sound suppression water system are still intact. The huge “tank farm’’ situated at some distance from the pad is now used to store liquid oxygen, liquid hydrogen, nitrogen, and helium for other programs [83].

There have been several proposals to revive the UKSS for new rocket programs. One suggestion around the turn of the century was to use it for test launches of the Avrora rocket, a much upgraded version of the Soyuz rocket that would be launched on commercial missions from Christmas Island in the Indian Ocean under a contract between the Asia Pacific Space Center, RKK Energiya, and several other Russian organizations. Unfortunately, the deal to build the rocket and the island launch pad fell through [84]. The UKSS has also been eyed to serve as a launch pad operated and financed jointly by CIS countries for launches of Angara rockets. In the late 1990s there was RKK Energiya’s short-lived Sodruzhestvo proposal and more recently the UKSS was also considered for the Russian/Kazakh Bayterek complex. However, it was later decided that Bayterek will be built on an old Proton site. In late 2004 a group of US experts visited the UKSS and supporting facilities to study its possible use as “an international spaceport’’, but nothing has been heard of such plans since [85].

At any rate, UKSS’ designers say the pad can be quite easily modified to accommodate launch vehicles other than Energiya. Against Soviet/Russian tradition, it would even be possible to assemble rockets on the UKSS vertically. That may eventually become a necessity, because at least part of the railroad track that used to connect the UKSS with the MIK RN has reportedly been removed and reused to connect that assembly building with Site 31 for Starsem missions. The two crawler transporters remain parked outside the MIK RN [86].

Quite possibly, the next Russian winged spacecraft to make its appearance will not be a state-sponsored vehicle, but one financed by the private sector for suborbital tourist missions. Suborbital space tourism got a major boost in the 1990s with the initiation of the X-Prize (later renamed Ansari X-Prize), a $10 million prize designed to jumpstart the space tourism industry through competition between entrepreneurs and rocket experts around the world. The cash prize would be awarded to the first team that privately built and launched a spaceship capable of carrying three people to 100 km altitude and repeat that launch with the same ship within two weeks.

One of the 26 contenders for the X-Prize was a consortium consisting of the Experimental Machine Building Factory (EMZ) in Zhukovskiy, the Russian Sub­orbital Corporation, and the Virginia-based company Space Adventures, which also brokers deals for millionaires wishing to fly to the International Space Station. On 14 March 2002 the consortium unveiled plans for a system called Constellation XXI, consisting of the M-55X carrier aircraft and the C-XXI suborbital vehicle, both designed by EMZ, which played a leading role in the Buran program as part of NPO Molniya. The M-55X is a modified version of the M-55 “Geofizika”, a high – altitude research aircraft that made its debut in 1988. Journalists invited to EMZ’s facilities were shown one of the M-55 aircraft with a wooden mock-up of the rocket plane suspended above it. The C-XXI was described as a 7.7 m long and 2.02 m high vehicle capable of carrying one pilot and two passengers. It was made up of a crew module and a jettisonable engine unit.

The plan was for the M-55X to carry the C-XXI to an altitude of 17 km, where the pair would separate at a speed of 750 km/h. Shortly afterwards, the C-XXI would ignite a solid-fuel rocket engine that would accelerate it to a speed of 1,600 km/h and take it to an altitude of 50 km. After engine burnout, the engine unit would be separated, while the rocket plane continued to an altitude of over 100 km, allowing the passengers to experience 3 to 5 minutes of weightlessness. The C-XXI would then make a 360° turn to glide to a landing on an ordinary runway at a speed of 220 km/h. All three crew members were supposed to wear pressure suits and could be ejected from the vehicle during the entire piggyback ride on the M-55X as well as during the early and final stages of the ship’s autonomous flight [33].

The Ansari X-Prize was eventually won by Mojave Aerospace Ventures/Scaled Composites, the team led by the famed US aerospace designer Burt Rutan and sponsored by financier Paul Allen. After several powered test flights earlier in the year, the team’s SpaceShipOne, dropped from the White Knight One carrier aircraft, made two successful suborbital flights in September-October 2004 less than two weeks apart. Building upon the success of SpaceShipOne, Rutan teamed up in July 2005 with the British business tycoon Richard Branson to form a new aerospace production company (the “Spaceship Company”) that will build a fleet of commer­cial suborbital spaceships (SpaceShipTwo) and launch aircraft (White Knight Two). Owned and operated by a company called Virgin Galactic, at least five ships will be carrying two pilots and up to six paying passengers on suborbital flights reaching an altitude of 140 km.

Although Constellation XXI lost out in the X-Prize competition, its design now serves as the basis for a new suborbital tourist project that may eventually compete with Virgin Galactic. Space Adventures has again joined forces with EMZ to build an advanced version of the C-XXI that will use the same M-55X as its parent aircraft. Dubbed Explorer, the rocket plane will be able to haul five people to the edge of space and have emergency rescue systems similar to those of its predecessor. Also part of the partnership is Texas-based Prodea, a firm founded by the Ansari family, which put up the $10 million prize money for the X-Prize competition. Space Adventures intends to sell Explorer vehicles to operator companies to conduct the actual missions. It has deals in place to fly the Explorer vehicles from spaceports near major airports in the United Arab Emirates and Singapore [34].

Whatever the motives, by the middle of 1975 a number of joint meetings between officials of the Ministry of General Machine Building and the Ministry of Defense resulted in a Soviet shuttle taking center stage in future plans for the country’s piloted space program. There seems to have been particular pressure from GUKOS, headed at the time by Andrey Karas. The consensus by now was also that the vehicle should be similar in size to the Space Shuttle in order to respond to whatever threat the

American vehicle would eventually pose. It was also felt that the time needed to develop a big or small shuttle wouldn’t be too different anyway.

From an economic and operational viewpoint, there was clearly no immediate need for the Soviet Union to build a shuttle, but in times of almost limitless budgets for defense-related programs any such considerations were easily outweighed by military arguments. Still, there was much division in the industry, mainly within NPO Energiya, on the need to press ahead. Therefore, GUKOS ordered the TsNII-50 research institute to perform a study of the military potential of such a system. Strangely enough, TsNII-50 head Gennadiy Melnikov, wishing to satisfy both camps, ordered preparation of two reports, one confirming the need to build a Shuttle equivalent, and the other demonstrating there was no need for such a system. The negative report was sent to the opponents of the reusable spacecraft and the positive report to the proponents. Eventually, however, both reports landed on the desk of Dmitriy Ustinov, who was dismayed to learn that two contradictory reports had been prepared by one and the same institute. Ustinov subsequently summoned Glushko to his office to clarify the situation, but Glushko, still not enthusiastic about a shuttle program, instead decided to send Valeriy Burdakov.

Burdakov, an avid shuttle supporter, had headed the shuttle team under Mishin, but after Glushko’s arrival had been demoted to a position under shuttle chief designer Sadovskiy. Glushko’s decision not to go himself and not even send Sadovskiy was his way of showing his lack of interest in the program, but it apparently had a boomerang effect. Burdakov and Ustinov talked at length about reusable spacecraft, with Ustinov showing particular interest in the military applica­tions of such systems. Asked about the goals of the US Space Shuttle, Burdakov told Ustinov among other things about its capability to place giant laser complexes into orbit. The two agreed that much of the N-l infrastructure at Baykonur (mainly the giant N-l assembly building and the two launch pads) could be modified for use by a reusable spacecraft. The conversation ended with Ustinov ordering Sadovskiy’s department to draw up a detailed report outlining the possible designs, missions, and operational aspects of a Soviet reusable space system [21].

Given Ustinov’s influence, this order was more than a trivial matter and a considerable step on the road to final approval of a Soviet shuttle system. In

September 1975 Ustinov convened a meeting at NPO Energiya, where it was agreed to speed up the release of a government and party decree on such a system, seen as the official endorsement of the program and the go-ahead to actually design and build the hardware [22]. In a letter dated 21 December 1975, KGB chief Yuriy Andropov once again reminded Ustinov of the Space Shuttle’s military capabilities, emphasizing that its 30-ton payload capacity allowed it to orbit big spy satellites and space-to – ground weapons [23]. Roald Sagdeyev confirms Ustinov’s role in the final decision to build a Space Shuttle equivalent:

“I heard that [Buran] was adopted mainly due to insistence from Ustinov, who had made the following argument: if our scientists and engineers do not see any specific use of this technology now, we should not forget that the Americans are very pragmatic and very smart. Since they have invested a tremendous amount of money in such a project, they can obviously see some useful scenarios that are still unseen from Soviet eyes. The Soviet Union should develop such a technol­ogy, so that it won’t be taken by surprise in the future’’ [24].

The unavoidable impression one gets when comparing drawings and pictures of the Space Shuttle and Energiya-Buran is that the Soviet vehicle is in many ways a copy of the American one. There were of course basic differences with the Space Shuttle, the most notable ones being the use of liquid vs. solid-fuel boosters, the placement of the cryogenic engines on the external tank rather than the orbiter, the use of cryogenic rather than hypergolic propellants for the orbiter’s orbital maneuvering and reaction control systems and Buran’s higher degree of automation.

However, there is no denying the fact that other differences between the two systems were in details rather than in fundamental design. The similarities far out­numbered the differences. The tank section of the core stage was a virtual carbon copy of the Shuttle’s External Tank and the orbiter was almost identical in layout, dimensions, and shape to its US counterpart. The similar dimensions were a logical result of the requirement to match the payload capacity of the Space Shuttle. As for the strikingly similar shape, when asked about this, Soviet officials usually responded along the lines that the laws of aerodynamics left little room for other designs. However, the dozens of orbiter outlines studied by NASA in the late 1960s and early 1970s and by the Russians themselves disprove this claim. In the end, Buran’s shape was largely determined by the very same Defense Department requirements that

had forced NASA into the design for its Space Shuttle Orbiter (high cross-range capability and ability to transport large payloads). As one veteran admits:

“The deciding factor was not aerodynamics. We were in a position of having to play catch-up [with the Americans] … This is where the, unfortunately, classical opinion in our defense industry surfaced: the Americans aren’t dumber, do it the way they do!’’ [72].

Indeed, Buran was not the only example of following Western designs. Similar examples can be found in other branches of the Soviet industry as well, particularly in aviation. Among the more striking ones were the Tu-4 bomber, a clone of the B-29, and the Tu-144 “Konkordski”, the Soviet equivalent of Concorde. In some instances this was simply the fastest and most practical way of achieving parity, with the Russians apparently being not all too concerned about losing face in the process.

It should be pointed out though that Buran was the only obvious case of copying in the Soviet space program. While several Soviet manned and unmanned space projects were a response to American programs and intended to match their cap­abilities, the Russians usually came up with their own design solutions (e. g., Spiral vs. Dyna Soar and Almaz vs. the Manned Orbiting Laboratory). In the N-1/L-3 manned lunar-landing project, a program comparable in scale with Energiya-Buran, the Russians adopted the same Lunar Orbit Rendezvous technique as the Americans, but built a rocket that was fundamentally different from the Saturn V. Perhaps the negative experience with that project was one of the reasons that led them to more closely mimic the US design when the next program of comparable proportions came along. If things went wrong again, managers and designers would at least not be held accountable for “having done it differently than the Americans”.

More fundamentally though, this time around the Russians were not sure what the ultimate objectives of the American program where. Whereas the goal of Apollo unequivocally had been to put a man on the Moon, the motives behind the devel­opment of the Space Shuttle were much more nebulous from the Russian perspective. Fearing the military capabilities of the Shuttle, they felt it necessary to build an equivalent system, but, unsure of what exactly the threat was, they had little choice but to stick closely to the American design to make sure they would be able to respond to whatever strategic missions the Shuttle would eventually perform. Buran was built not out of some fundamental need in the Soviet space program, but as an answer to potential military and other applications of the Space Shuttle. This would eventually become the root cause of its downfall in the early 1990s.

By copying many aspects of the Space Shuttle design, the Russians could take advantage of the American experience, saving them a lot of research and develop­ment time. Although there is little evidence to support this, there can be little doubt that in designing their vehicle the Russians made use of the literature openly available on the Space Shuttle Orbiter. By the time the Energiya-Buran project got underway in 1976, the Shuttle’s design had been frozen for nearly two years and the first Orbiters were under construction. On the other hand, there is probably nothing fundamental that the Russians changed in their design based on actual US flight experience, because by the time Columbia flew STS-1 in April 1981 Buran’s own design had been finalized.

Still, the copying that irrefutably took place should not be used as an argument to belittle the Soviet accomplishment. No matter how much the Russians relied on Shuttle literature and blueprints, they still needed to develop the technology, the materials, and the infrastructure and do the testing all by themselves. Considering their overall less mature state of technology and the country’s smaller economic

potential, this was a remarkable feat, irrespective of whether the expenditures were justified or not.

For ascent and return the mid-deck could have seats installed for up to six crew members. In orbit it served as the living and sleeping quarters for the crew, containing (among other things) lockers for stowage, sleeping bags, a galley with a small reclining table, washing facilities, and a toilet. In the aft of the mid-deck there was room for an internal airlock to conduct spacewalks during non-docking missions. For docking missions Buran would have carried a combined docking system/airlock installed in the cargo bay just behind the crew compartment.

The mid-deck also housed three small equipment bays with radio equipment and thermal control systems that could be accessed by the crew via panels. There was a

hatch on the port side of the mid-deck for normal crew ingress and egress, which could be opened very quickly by the crew in emergency situations. As on the Orbiter, there was a small porthole in the middle of the side hatch. Access to the flight deck was via two interdeck openings (left and right), although only the left one was supposed to be used in flight. The mid-deck had its own instrument panel (17M212) with among other things an on-board clock and an emergency warning system. There were also separate instrument panels for the airlock (17M213) and the docking adapter (17M214).

This was the prime navigation aid for final approach and landing, providing azimuth and elevation data from an altitude of about 7 km. The RMS was a standard all­weather scanning-beam microwave landing system (MLS) similar to those adopted for civil aircraft in the early 1980s by the International Civil Aviation Organization. In microwave landing systems antennas located on the ground transmit a reciprocat­ing beam to an aircraft, while the aircraft measures the interval between a pair of received beams and thereby determines the azimuth and elevation angle. Buran was equipped with three RMS sets (17M901) each containing a transmitter/receiver and a decoder (34.5 kg). The ground-based component incorporated an azimuth and elevation antenna on either side of the runway, providing azimuth coverage of about 30 degrees from the runway centerline and vertical guidance up to 30 degrees. The antennas had a much greater range (at least 25 km) than traditional aviation micro­wave landing systems.

The RMS was very similar to the Space Shuttle’s Microwave Scan Beam Landing System (MSBLS). VNIIRA (the All-Union Scientific Research Institute of Radio Equipment), the Leningrad institute that built the system, was criticized by some for not using an advanced aviation microwave landing system called Platsdarm. This was under development at the institute by the end of the 1970s and featured phased-array

antennas with electronic scanning rather than dish antennas with mechanical scanning as in the RMS. Some felt that the simultaneous work on the Buran system and Platsdarm was a wasteful duplication of effort.