Category Soviet and Russian Lunar Exploration

The cancellation of Luna 25 in 1977 marked the end of the Russian programme of lunar exploration. Nevertheless, the chief designer of the Soviet space programme was not ready to give up completely on a manned flight to the moon, for Valentin Glushko persisted with dreams for lunar exploration, presenting his last set of ideas in 1986, just three years before his death.

AFTER N-l: A NEW SOVIET MOON PROGRAMME?

Strangely enough, the suspension of the N-1 programme in 1974 did not mean the final end of the Soviet manned moon programme. The new chief designer, Valentin Glushko, announced that the whole space programme would be reappraised and a fresh start made in reconsidering strategic objectives. The only definite decision was that the N-1 would not fly for the time being, if at all. Glushko set up five task forces, one of which was headed by Ivan Prudnikov to develop the idea of a lunar base and another the idea of a new heavy-lift launcher. Glushko personally began to sketch a new series of heavy launchers called the RLAs, or Rocket Launch Apparatus, capable of putting 30, 100 and 200 tonnes into orbit respectively.

When the Politburo met in August 1974, it actually reaffirmed the general objective of Soviet manned missions to the moon. Ivan Prudnikov duly completed, by the end of that year, the plans for a lunar base. The base was called Zvezda, or ‘star’ and featured teams of cosmonauts working on the moon for a year at a time, supplied by the new, proposed heavy-lift rocket. Their proposals were formally tabled, along with the outcome of the four other task forces, in 1975. Design of a heavy-lift launcher appropriately called Vulkan, able to deliver 60 tonnes to lunar orbit, was sketched out. In an abrupt turnaround, Vulkan would be powered with hydrogen fuel, the one system Glushko refused to develop for Korolev. Glushko even designed new hydrogen-fuelled engines, the RD-130 and RD-135, the latter with a specific impulse

of no fewer than 450 sec. A lunar expeditionary craft or LEK was designed, not that different from the long-stay lander of Mishin’s N1-L3M plan.

Although Glushko put his full force behind Zvezda, it attracted little support overall and none from the military at all. Crucially, the president of the Academy of Sciences, Mstislav Keldysh, would not back it. He was never a close friend of Glushko and was wary of the extravagance of the project. The cost, estimated at 100bn roubles, was too much even for a Soviet government not normally shy of extravagant projects. Keldysh let the process of consideration of the project exhaust itself so that it would run out of steam [1]. Glushko tried to save some face with a scaled-down project, but this won little support either. The basic problem was that Glushko had replaced a real rocket (the N-1) and a real programme (N1-L3M), both with diminishing political support, with a theoretical rocket (Vulkan) and a programme (Zvezda) that had none. The Soviet leadership began to regard the Soviet manned moon programme as having been a failure, a waste, a folie de grandeur that the country could not afford. Leonid Brezhnev had a mild stroke in 1975 and decisions were taken ever more by a shifting group of ministers and generals. This was not a leadership that would take a big decision and see it through.

In the event, the most significant project to emerge from the strategic reconsidera­tion of 1974-6 was the Energiya-Buran heavy launcher and shuttle system, which was driven by military imperatives to match the American space shuttle. No one can point to a particular day or decision on which the Soviet manned moon programme died, but it withered in mid-1975 and was effectively gone by March the following year, 1976. Despite this, Valentin Glushko even once briefly returned to the moon base idea in the 1980s, outlining how a small base might be built using the Energiya rocket, but he won no support in a country entering ever more difficult economic conditions. Despite their declining political fortunes, the moon base projects reached a certain level of detail and are outlined here.

In the course of the mid-1960s, the Soviet Union built the equipment it required for manned lunar exploration. This comprised the Proton rocket, to fly spacecraft around the moon, and the N-1 rocket, designed to land cosmonauts on the moon. The Soviet Union built the spacecraft necessary to circle and land on the moon: the Zond to pass round the moon and return to Earth, the LK lunar lander and the LOK lunar orbiter. And, finally, the Soviet Union trained a squad of cosmonauts to fly there and land there. Each is described in turn.

THE ROCKET FOR CIRCLING THE MOON: THE UR-500K PROTON

The UR-500 Proton rocket dates to October 1961, when Russia detonated, over the northern Arctic island of Novaya Zemlya, its first 58-megatonne thermonuclear superbomb. This bomb was carried aloft and dropped by a Tu-95 bomber, but there was no way these ageing propellor planes were going to reach, never mind drop their cargoes on New York. For this purpose, a new, powerful rocket was required. Nikita Khrushchev turned to Vladimir Chelomei, the man who gave him his military rocket fleet who now promised to build him an ever bigger rocket called the Universal Rocket 500, so-called because it could be used for many other purposes (hence UR-500) [1]. Not long afterward, Khrushchev was bragging about the Soviet Union’s new ‘city – buster’ rocket.

In the event, the UR-500 was never taken into the armaments as a city-buster and was cancelled as a military project very early during the Brezhnev government. The UR-500 survived and was converted to civilian use. Vladimir Chelomei astutely persuaded the Kremlin that the UR-500, with suitable upper stages, could send a small manned spacecraft round the moon and that this was a much quicker, neater way of doing so than Sergei Korolev’s Soyuz complex, without any of the uncertain­ties of Earth orbit rendezvous. As a lunar rocket, it was called the UR-500K.

Chelomei’s moon rocket was a three-stage booster carrying nitrogen tetroxide and unsymmetrical dimethylmethylhydrazine (UDMH), the fuel abhorred by Korolev. The engine of the first stage was built by Valentin Glushko’s OKB-456 and became the famous RD-253 engine. The second – and third-stage engines were built by the Kosberg Design Bureau. The Proton had the most advanced rocket engines in the world for 20 years. Valentin Glushko’s RD-253 engines recycled their exhaust gases to create a closed-circuit turbine system. Pressures of hundreds of atmospheres were obtained on delivery. Each engine weighed a modest 1,280 kg. The turbines went round at a fantastic 13,800 revolutions a minute or 18.74 MW. Temperatures reached 3,127°C in the engine chambers and their walls were plated

with zirconium. OKB-456 developed the first three stages, but the fourth came from rival Korolev’s design bureau. Here, block D was developed by Mikhail Melinkov in OKB-1 [2]. This relied on the traditional liquid oxygen and kerosene that was the hallmark of Korolev’s approach.

The RD-253 was perhaps the greatest breakthrough represented by the Proton. Equally significant was the clustering of fuel tanks of the side of the bottom stage.

Russian rockets are limited to a diameter of 4.1 m, the widest size that can be trans­ported by the rail system. This restriction would make any powerful rocket far too slim to be viable. What Chelomei did was develop the main core as the oxidizer only, within the 4.1m limit and later attach the fuel tanks to the side of the rocket. They were built separately, transported separately from Moscow to Baikonour and then attached in finishing hangars beside the pad in Baikonour. With the tanks attached, the diameter of the Proton on the pad is 7.4m.

Launching the Proton required the building of fresh pads to the northwest of the cosmodrome. Two sets of double pads were built, called Area 81 and Area 200. Each had a left pad and a right pad (81L, 81P, 200L, 200P). A Proton is brought down to the pad on a train trailer and then erected into the vertical position. Around the pad are 100 m tall lightning conductors and four 45 m tall floodlight stands. A shallow flame trench takes away the rushing roar of the engines firing at take-off from both sides.

Proton was and still is built in the Fili plant in Kaliningrad, now known as Korolev. This was an old automobile factory, taken over by the Bolsheviks to build German Junkers planes in the 1920s and then Tupolevs. It became effectively part of Vladimir Chelomei’s OKB-52 in 1960 but is now known as Khrunichev, an affiliate of Lockheed Martin.

The design history of the Proton is, compared with that of the N-1 which follows, not well known. It took Chelomei and his OKB-52 fewer than two years to design the UR-500 (1961-3) and fewer than two years to build it (1963-5), all the more remark­able granted its cancellation as a military weapon. The design was subject to rigorous ground testing and Chelomei refused to rush things. This paid off, for the UR-500’s first mission went like a dream, lofting the first of a series of four large cosmic ray satellites over 1965-8. They were called Proton and the first, Proton 1, was the largest scientific satellite ever launched up to that point, weighing in at no less than 12 tonnes (as a satellite, it was a failure, but that was not the launcher’s fault). Of the Proton’s first four launchings, only one failed, making it the most promising rocket of its day. The first launch was well publicized. The Western media quickly recognized a rival to the American Saturn IB moon rocket and came hastily but correctly to the immediate conclusion that an early task for the rocket was to send a Russian around the moon first. Possibly because of its military origins, the Russians kept back details of the Proton for well over 20 years and the first proper pictures of a Proton launch were not released until the 1980s.

Despite its promising start and despite Chelomei’s thoroughness, the Proton was to have an exasperating development history. The early promise was not maintained, and of its first 29 launches, no less than 14 failed, arguably costing the Soviet Union the round-the-moon race, as well as numerous lunar and Mars probes. At the time, nobody would have credited it that the Proton would go on to become one of the most reliable rockets in the world. Proton was launched for the 300th time in June 2003. Although there were occasional final-stage failures with block D, lower-stage failures became most unusual (there were two in the 1990s, when quality control in the manufacturing plant slipped during the period of greatest economic difficulty). A new version of the Proton was even introduced, the Proton M, in 2001.

Russia’s UR-500K Proton

Length 44.34 m

Diameter 4.1 m

When Neil Armstrong, Buzz Aldrin and Michael Collins returned from the moon, television viewers were amazed to see the returning heroes wrapped up in biological suits with masks and unceremoniously ushered into what looked like a camper caravan. The purpose was a serious one: to ensure that they were not contaminated with lunar soil that might in turn affect other Earthlings. The caravan was transferred to Houston where the astronauts spent the rest of their three-week quarantine.

The USSR developed a similar series of precautions and its own isolation unit. Lunar soil samples were to be received in the Vernadsky Institute of Geological and Analytical Chemistry, but a small lunar isolation unit was built in Star Town. In the Vernadsky institute, a two-floor room was set aside with two cylindrical glovebox units, each with four large viewing ports.

The opportunity to use the Soviet isolation unit came in 1970, following the mission of Soyuz 9. This was a two-man spaceflight designed to push back the then Soviet endurance record of five days and pave the way for the first Soviet space station, Salyut, due in 1970. The cosmonauts chosen, veteran Andrian Nikolayev and new­comer Vitally Sevastianov, spent 17 days in the small Soyuz cabin in June 1970.

Soon after landing, the cosmonauts were transferred to the isolation unit in Star Town by way of Vnukuvo Airport and not let out till 2 July, two weeks later: the same period of isolation as a moon journey would require. Flight debriefing was carried out behind glass partitions: telephones and microphones were used. The isolation complex had probably cost a lot to build and this was the only use it was to get. Soviet Weekly tried to explain:

The isolation isn’t because offears that Nikolayev and Sevastianov may have brought back strange diseases from outer space! Indeed the precautions are for the opposite reason. Doctors consider it possible that protracted space flight may lower normal immunities and they are therefore making sure that the spacemen are protected from earthbound infection until they have acclimatized.

Although Soviet spaceflights subsequently grew longer and longer, the facility was never used again. In reality, there was an element of farce about the whole episode. The Soviet Weekly explanation was the exact opposite of the truth, for the ultimate purpose of the unit was precisely to prevent infection from space-borne diseases. The real aim of the unit was never publicly revealed and we do not know what became of it subsequently. The theory behind the need for Soyuz 9 isolation had already been

completely undermined anyway at the point of landing. Nikolayev and Sevastianov were in weak condition when they touched down and had to be assisted from their cabin. Pictures released many years later showed them being helped and comforted, and if there had been any plans to rush them into biological protection suits, they must have been quickly abandoned. Had they indeed carried the cosmic plague with them, the entire recovery team would have been quickly infected.

Thus, by 1972 the N-1 was in redesign. The old N1-L3 plan had now been superseded by a more ambitious plan, using a redesigned launcher, equipped with the hydrogen – powered engines that had brought the Americans so much success. Once the N-1 was perfected, Mishin could look forward to eclipsing the Apollo landings with the beginnings of a Soviet base on the moon. The Americans might get there first, but Soviet cosmonauts would be the first to really live there and explore. Three more N-1s were under construction and one was now almost ready.

With the N1-L3M plan now over a year under way, it was time for the fourth full test of the N-1. Although there had been some pressure to cancel the programme after the third failure, there was a strong conviction that the rocket must now be near to success. Following the third failure, further modifications of the rocket took place: [7]

• Better thermal protection for tanks, cables and pipes.

• New control system.

• Improved performance monitoring, with 13,000 sensors sending back data.

This N-1 was the first Soviet launch to use a digital guidance and control system, one overseeeing the engines, gyroscopes and accelerometers. The S-530 computer was developed by the Pilyugin design bureau and was used not only for the N-1 but the LOK and LK. The rocket’s telemetry system relayed back high-density data, some analysts estimating at a rate of 9.6Gbyte/sec on up to 320,000 channels on 14 frequencies, so fast that eavesdropping American electronic intelligence satellites could not keep up. Commands could be sent up to the ascending N-1 at the same pace.

Much improved engines were also in preparation, to be installed on the fifth flight model. The fourth N-1 launch took place on 23rd November 1972, directed by Boris Chertok, Mishin’s deputy (the chief designer was in hospital at the time). This N-1 carried a dummy LK but, for the first time, a real LOK, which was intended to be put in lunar orbit and return to Earth. To reach the moon, the N-1 would have used a southbound course for translunar injection. A flight plan was approved by Vasili Mishin in July and subsequently published, highlights of which were:

• Burn-out of Earth orbit after one day on 24th November.

• Two course corrections en route to the moon.

• Lunar orbit insertion after 98 hours, orbiting at 175 km on 28th November.

• Change in lunar path on the 5th and 27th orbit.

• Descent to 40 km over the moon.

• Landing site photography on orbits 14, 17, 34 and 36.

• Jettison the dummy LK on orbit 37.

• Drop the LOK orbital module on orbit 39.

• LOK to blast back to Earth on orbit 42, on 1st December.

• Course corrections 24 hours after trans-Earth injection and 6 hours before reentry.

• Splashdown in the Indian Ocean on 4th December (Clark, 2002).

At 72 sec after take-off, the fourth N-1 was flying longer, higher and faster than any of its predecessors. Hopes rose that the first staging of an N-1 might now take place just short of the 2 min mark. At 90 sec another hurdle was passed when the six core engines were shut down on schedule (this was a procedure to reduce G forces and vibrations). Then all of a sudden it all went wrong again. Engine # 4 caught fire, for reasons that were never satisfactorily explained, right at the end of its burn. There was then the bright flame of an explosion at the tail. The rest of the rocket then quickly blew apart, mere seconds from second-stage ignition. The escape rocket engine fired the payload, the LOK, free. Again, a human crew would have survived.

Flights of the N-1

Date Outcome Payload [8] [9]

Lavochkin. A date was even set for the launch: 17th September 1975, with a landing on Mars on 22nd September 1976, liftoff from Mars on 27th July 1977 and a return to Earth on 14th May 1978 [19].

Mishin was close to bringing the fifth N-1 down to the pad in May 1974. It was scheduled to fly in August 1974, with the fully improved Kuznetsov engines. An all-up unmanned mission in lunar orbit was scheduled. Even as he did so, the plotters moved.

Mishin had come increasingly under fire not only for the failures of the N-1 programme but also for the difficulties experienced in other parts of the programme. The early 1970s were bad years for the Soviet space programme, for not only were there the problems with the moon programme, but three cosmonauts were lost on Soyuz 11, three space stations were lost over 1972-3 and a fleet of four probes sent to Mars in 1973 suffered a series of computer failures. In some senses, it is a surprise that he lasted as long as he did. Mishin was aware of the criticism, but not that his enemies were preparing to move against him, which they did when he was in hospital. In May 1974, they persuaded Leonid Brezhnev to remove Vasili Mishin from his post as chief designer. He was dismissed on 15th May and replaced at once by Chief Engine Designer Valentin Glushko, who was shortly elevated to membership of the Central Committee of the Communist Party, the apex of political power.

Within days, Glushko suspended the N-1 programme. The sudden suspension of the programme cause widespread shock throughout the Soviet space programme, most so in Kyubyshev where it was built. Alexei Leonov recalls what a devastating blow this was. He blamed Mishin for his failure to present his case properly to the political leadership [20]. Leonov believed that, had Korolev lived, the Soviet Union would certainly have sent a cosmonaut around the moon first. He was less sure that they could have landed on the moon first, but Korolev could have learned from the mistakes with the N-1. They would have got there in the end.

Even after Mishin had been removed, his engineers lobbied hard to be permitted even suborbital flights down the Tyuratam missile range, but to no avail [21]. Others argued, equally unsuccessfully, that even if the moon programme were to be aban­doned, the N-1 would still be needed to launch large space stations. Some took out the old N-1-for-Mars design, now called the N-1M, trying to reinvent the rocket for its original mission, intended as far back as 1956. This inevitably prompted a rival design from Chelomei, the UR-700M and then the UR-900, raising the tedious prospect of the battles to the moon being refought again, but this time all the way to Mars [22].

Over the next two years, the Soviet space programme was gradually reoriented, but in a much more fundamental way. The future of the space programme was fought out at a meeting of the Military Industrial Commission on 13th August 1974 [23]. The main imperative seems to have been Glushko’s desire for a clean sweep, replacing the N-1 with his own family of launch vehicles (ultimately this evolved into Energiya); a reaffirmation of the value of orbital stations, where the USSR had achieved some modest success; and the need for a space shuttle to match the Americans. The military were not interested in going to the moon, but they were interested to match the shuttle. Now that he had finally triumphed over his dead rival, Korolev and his still alive successor Mishin, Glushko very much wanted to remake the Soviet space programme in his own image [24]. Glushko was undoubtedly a brilliant engineer, but critics found

him petty, gossipy, vainglorious and someone who liked to settle old scores. The political leadership was anxious to reign back costs and even Brezhnev, a supposed lover of projets de grandeur, understood the enormous cost to the Soviet economy of moon programmes. Although large-scale lunar and Martian projects continued on the drawing board for another two years, enthusiasm for them diminished to the point that they could be finally buried. Again, the Soviet decision-making process moved slowly and, apart from suspending the N-l, nothing was decided immediately. A consensus emerged, driven by Glushko, who had now combined his old bureau, OKB – 456, with Korolev’s old OKB-l, not to mention the Kyubyshev plant as well, to form the greatest mega-bureau of all time, Energiya. Following his death in 1989, they were again separated, the former becoming RKK Energiya and the later Energomash.

The three great chief designers of the Soviet space programme

1946-66 Sergei Korolev

1966-74 Vasili Mishin

1974-89 Valentin Glushko

In March 1976, the N-l was finally cancelled and the order was given to destroy all the N-l hardware. Project 5M to Mars was cancelled, though the absence of the N-1 was not the only reason (it was eventually recognized as being over-ambitious). The only items to survive were: the NK-33 rocket engines, which were stored away in a shed in the Kuznetsov plant in Kyubyshev; four lunar landers, now to be found in various museums; and half an N-1 fuel tank, which was converted to a bandstand shelter in a park in Leninsk. The N-1 pads were converted to serve for Glushko’s new rocket, the Energiya launcher, and it was from one of them that his Buran space shuttle made its first and only mission in November 1988. As for the former chief designer, Mishin was sent to lecture at the Moscow Aviation Institute, and, when glasnost broke, emerged to break the story of the N-l.

Heartbreaking though these decisions were for the designers, the cosmonauts who had hoped to fly to to the moon also felt an acute sense of disappointment. What happened to the cosmonaut squad? Once Apollo 8 had flown around the moon, the prospects of an L-l manned mission around the moon receded, although briefly rekindled when consideration was given to a mission to mark Lenin’s centenary in 1970. With the failure of the second N-l rocket in July 1969 and the American landing on the moon later that month, the prospects of a Soviet manned flight to the moon depended on the taming of the N-l rocket, which was nowhere in sight. The squad’s members had so little to do that they were permitted to make overseas trips, though some were recalled when they told too much of Soviet intentions. Autumn l969 saw the troika flight of three Soyuz spacecraft, mainly taking cosmonauts from the main Soyuz training groups but also some less prominent members of the lunar group (e. g., Vladislav Volkov). Plans were put forward for 1970-1 for at least one set of Kontakt missions to test out the lunar orbit docking system, with members drawn from the moon teams and farther afield. These missions were eventually cancelled in late 1970. When the head of the cosmonaut squad, General Kamanin, came to assemble his crews for the first manned space station missions in spring 1971, he chose cosmonauts from the round-the-moon and lunar-landing teams, like Nikolai Rukhavishnikov (research engineer, Soyuz 10) and Alexei Leonov (original commander, Soyuz 11). No specific training was ever done for the N1-L3M missions and no simulators were ever built. The moon team was formally disbanded in May 1974, matching the suspension of the N-1 programme, although there cannot have been many left at this stage, most having been reassigned to the manned space station programme. Last to go was navigator scientist Valentin Yershov, who alleged he was put out either for not joining the party or else to make way for nominees of new Chief Designer Valentin Glushko.

Winding down the moon race: cutbacks and redirection

1 Jan 1969 Party and government resolution to continue the moon programme, develop

an unmanned alternative programme and develop space stations.

Sept. 1969 First plans drawn for the N1-L3M.

Spring 1971 N1-L3M presented to expert commission.

August 1971 Cancellation of N1-L3 programme, replaced by the N1-L3M programme. 15 May 1972 Technical proposals for the creation of the N1-L3M complex approved.

May 1974 Mishin deposed; Glushko becomes chief designer; N-1 suspended. Cos­

monaut members disbanded March 1976 N-1 finally cancelled.

Moon bases had been part of Soviet thinking for some time. For Glushko, a moon base had a number of attractions. With Apollo over and the shuttle in development, there was no prospect now of the Americans establishing a moon base. By contrast, the world might be impressed by a permanent Soviet settlement on the moon. What would it have looked like?

A considerable amount of homework had already been done on moon bases. Design for a Soviet lunar base dated to the Galaktika project, approved by the government in November 1967. This mandated the study of the issues associated with lunar and planetary settlements [2]. The work was done not by one of the normal space design bodies but instead by the bureau associated with the construction of the cosmodromes, Vladimir Barmin’s KBOM. Work began in March 1968. Within the broader Galaktika programme, whose broad remit was the solar system as a whole, KBOM designed a full lunar base called Kolumb, or Columbus, constructed a full – scale habitation model and built a number of scale models, making its report as

Principles of the construction of long-term functioning lunar settlements in late 1969. KBOM designed a moon base for between four and twelve cosmonauts, working on the lunar surface for up to a year at a time. Up to nine modules might be delivered, telescoping out in length after their arrival. The study calculated that establishment of a moon base required the delivery, to the lunar surface, of about 52 tonnes of modules and equipment. Its key elements were:

• Pressurized habitation modules, buried under the regolith for protection from radiation, including a control centre.

• Construction equipment.

• Power supply centre, which could be solar, chemical or nuclear.

• Greenhouse to enrich oxygen, provide food and offer recreation.

• Logistics facilities for oxygen, water, waste disposal.

• Astronomy laboratory.

• Lunar rover, able to carry three cosmonauts across the lunar surface for up to three days to a distance of 250 km.

• Equipment for lunar exploration, such as drills and laboratory devices to examine rocks.

The western edge of the Ocean of Storms, already selected as the prime Soviet manned landing site, was nominated as the best possible location. Barmin was thanked for his work, for which he was paid 50m roubles, but cautioned that it was unlikely to be accomplished until the next century. The existence of this project was not eventually revealed until November 1987, when details were given on the Serbo-Croat and standard Chinese service of Radio Moscow’s overseas service.

In contrast to Proton, the N-1’s design history has been chronicled in some detail. The N-1 programme began on 14th September 1956, when the first sketches appeared in the archive of OKB-1. Korolev gave it the relatively bland name of N-1, ‘N’ standing for Nositel or carrier, with the industry code of 11A51. The concept was brought to the Council of Chief Designers on 15th July 1957, but it did notwin endorsement. The N-1 at this stage was a large rocket able to put 50 tonnes into orbit.

This was in dramatic contrast with the United States, where the Saturn V was constructed around a single mission: a manned moon landing. The N rocket, by contrast, was a universal rocket with broad applications. Korolev kept these purposes deliberately vague and, in order to keep military support for the project, hinting at how the N-1 could launch military reconnaissance satellites. The sending of large payloads to 24 hr orbit was also envisaged.

The N-1 languished for several years. Unlike the R-7, then in development, it did not have any precise military application and as a result the military would not back it. The situation changed on 23rd June 1960 when the N-1 was approved by Resolution #715-296 of the government and party called On the creation of powerful carrier rockets, satellites, space ships and the mastery of cosmic space 1960-7. Encouraged by the success of early Soviet space exploration, aware of reports of the developments by the United States of the Saturn launch vehicle, the Soviet government issued a party and government decree which authorized the development of large rocket systems, such as the N-1, able to lift 50 tonnes. The decree also authorized the development of liquid hydrogen, ion, plasma and atomic rockets. The 1960 resolution included approval for an N-2 rocket (industry code 11A52), able to lift 75 tonnes, but it was dependent on the development of these liquid hydrogen, ion, plasma and nuclear engines, suggesting it was a more distant prospect. The 1960 resolution also proposed circumlunar and circumplanetary missions. The implicit objective of the N-1 was to make possible a manned mission to fly to and return from Mars.

Such a mission was mapped out by a group of engineers led by Gleb Yuri Maksimov in Department # 9, overseen by Mikhail Tikhonravov. This would not be a landing, but a year-long circumplanetary mission. Maksimov’s 1959-61 studies postulated a heavy interplanetary ship, or TMK, like a daisy stem (nuclear power plant at one end, crew quarters at the opposite), which would fly past Mars and return within a year. In 1967-8, three volunteers – G. Manovtsev, Y. Ulybyshev and A. Bozhko – spent a year in a TMK-type cabin testing a closed-loop life support system. A related project, also developed in Department #9 but this time by designer Konstantin Feoktistov, envisaged a landing on Mars using two TMKs. The N-1 design, although it proved problematical for a man-on-the-moon project, was actually perfect for the assembly of a Mars expedition in Earth orbit.

Siddiqi points out that the N-1 Mars project and the development of related technologies took up a considerable amount of time, resources and energy at OKB-1 over 1959-63 [3]. Were it not for the Apollo programme, the Russians might well have by-passed the moon and sent cosmonauts to Mars by the end of the decade. Ambitious though the Apollo project was, Korolev had all along planned to go much farther.

The slogan of the GIRD group, written by Friedrich Tsander, never referred to the moon at all. Instead, its motto was ‘Onward to Mars!’

The fact that the original payload was 50 tonnes, far too little for a manned moon mission, demonstrates how little a part a moon landing played in Korolev’s plans at this time. Indeed, unaware of its origins, several people later questioned the suitability of the N-1 for the moon mission. Sergei Khrushchev said it was neither fish nor fowl, too large for a space station module, too small for a lunar expedition [4]. The head of the cosmonaut squad, General Kamanin, took the view in the mid-1960s that the design, going back to 1957, was already dated. The rival and ambitious Vladimir Chelomei felt he could do better with a more modern design.

Despite approval in 1960, the N-1 made very slow progress, and early the following year Korolev was already complaining that he was not getting the resources he needed. At one stage, in 1962, the government halted progress, limiting the N-1 project only to plans. An early problem, one that was to engulf the project, was the choice of engine. Korolev needed a much more powerful engine for such a large rocket. Korolev proposed kerosene-based engines for the lower stages and hydrogen – powered engines for the upper ones. He turned, as might be expected, to Valentin Glushko of OKB-456, asking him to design and build such engines. Valentin Glushko proposed a series of engines for the different stages of the N-1: the RD-114, RD-115, RD-200, RD-221, RD-222, RD-223. None of these was acceptable to Korolev, for all were nitric-based, anathema to him [5].

The ever-resourceful Korolev then turned to Kyubyshev plane-maker Nikolai Kuznetsov, asking him to make the engines using the traditional fuels of kerosene and liquid oxygen. Although Kuznetsov had no experience of rocket engines, he and his OKB-276 design bureau were prepared to give it a try. However, he knew he had no ability to develop high-powered engines, so a large number of modest-power kerosene-fuelled engines would have to do. In fact, despite his inexperience, the en­gines came out exceptionally powerful and lightweight, achieving the best thrust-to – weight ratios of the period. The engines were called NK, NK standing for Nikolai Kuznetsov. The first stage used NK-33s, the second NK-43s. There was little differ­ence between them except that NK-43 was designed for higher altitudes and had a larger nozzle [6]. Roll was controlled by a series of roll engines. For example, on the first stage, there were four roll engines of 7 tonne thrust each, assisted by four aerodynamic stabilizers.

First-stage separation would take place at 118 sec, at 41.7-km altitude, by which time the rocket would be travelling at 2,317 m/sec. The second stage would burn for over a further two minutes, reaching 110.6 km, with speed now at 4,970 m/sec. The third stage would then burn until 583 sec, by which time the stack had reached orbital altitude of 300 km and a velocity of 7,790 m/sec. Translunar orbit injection would be done by block G. This would use a single NK-31 engine, burning for 480 sec, to fire the stack moonward. Block D would then be used three times: [3]

The N-1 was originally designed to have hydrogen-powered upper stages. Research on hydrogen engines dated to 1959 in Arkhip Lyulka’s OKB-165 and I960 in Alexei Isayev’s OKB-2. The main engine design bureau was that of Valentin Glushko, but he had no time for hydrogen-fuelled stages. In May 1961, Korolev contracted Lyulka to build a 25 tonne thrust engine and Isayev a small one of 7 tonne thrust. Within two years, they were able to come back to him with the specifications of their motors, called respectively the 11D54 and 11D56. However, their progress was slow. A critical factor was the lack of testing facilities. Although both tried to get the use of the main testing facility at Zagorsk, priority was given to the testing of military rockets. In the event, they were not able to conduct the necessary tests until 1966-7. By 1964, Korolev had abandoned hope of getting hydrogen-powered engines available on time for the N-1 and went for more conventional solutions.

By summer 1962, the N-1 approached a critical design review. The N-1 design was studied by a commission presided over by Mstislav Keldysh for two weeks in July 1962. The Keldysh Commission gave the go-ahead for the N-1, with Korolev’s choice of liquid oxygen and kerosene engines. Siddiqi [7] points to the significance of this decision, for it forever fractured the Soviet space programme into rival camps: Korolev’s OKB-1 on one side; and on the other, Glushko’s OKB-456 and Chelomei’s OKB-52. The payload was set at 75 tonnes, merging the N-1 and N-2 design concepts (another interpretation is that the N-2 was in effect renamed and superseded the N-1). Either way, 75 tonnes was now the base line.

Two months later, on 24th September 1962, a government decree called for a first test flight in 1965. The N-1 was once again given the green light. Despite these changes, the N-1 and its engines continued to make very slow progress. Promised funding never arrived and despite seven years of design and redesign, no hardware had yet been cut. When the Soviet Union began to respond to the challenge of Apollo, Korolev saw the moon landing as an opportunity to give the N-1 the prominence he believed it deserved. On 27th July 1963, Korolev wrote a memo confirming that the N-1 would now be directed toward a manned landing on the moon. Now that the nature of American lunar ambitions had became more apparent, the N-1 was directed away from Mars and toward the moon. His first ideas for a lunar mission for the N-1 were to use two N-1s for his manned lunar expedition, employing the technique of Earth orbit rendezvous. The precise point at which Korolev moved from the Earth orbit rendez­vous profile to the lunar orbit rendezvous profile is unclear. Granted the difficulties they had experienced with getting funding for the N-1, the prospect of having to build only one, rather than two, for each moon mission must have been appealing. The favourable trajectory and payload economics of the American lunar orbit rendezvous method persuaded him that a single N-1 could do the job, but it would have to be upgraded again, this time from a payload of 75 tonnes to one of 92 to 95 tonnes, almost double its original intended payload.

When the decision to go to the moon was taken on 3rd August 1964, the N-1 was designated as the rocket for the lunar landing programme. The 95 tonne requirement had two immediate implications. First, the number of engines must be increased from 24 to 30, giving it a much wider base than had originally been intended. The 24 were in a ring and the additional six were added in the middle. Second, the fuel and oxidizer tanks would necessarily be very large. Korolev decided that spherical fuel tanks were to be used, eschewing the strapping of large fuel tanks to the side of the rocket. The diameters in each stage would be of different dimensions, making the system more complex and meaning that the rocket would be carrying a certain amount of empty space. The largest tank was no less than 12.8 m across! Korolev’s fuel tanks were so huge that they could not be transported by rail and had to be built on site at the cosmodrome. The first stage had 1,683 tonnes of propellant, of which no fewer than 20 tonnes were consumed before take-off!

Trying to get a 95-tonne payload out of a 75-tonne payload rocket design was quite a challenge. Other economies were sought and changes made:

• Setting a parking orbit of 220 km, lower than the 300 km originally planned.

• Additional cooling of fuels prior to launch.

• Thrust improvements of 2% in each engine.

• Use of plastic in place of steel in key components.

• Parking orbit inclination from 65° to 51.6° (later 50.7°).

• Reducing the crew of the lunar expedition from three to two.

Many different – and sometimes rival – branches and bureaux of the Soviet space industry were involved in the N-1 and the programme to put a Soviet cosmonaut on the moon. The N-1 was a huge industrial scientific undertaking, employing thousands

of people in Kyubyshev, Moscow, Dnepropetrovsk, Baikonour and many other locations. These were some of the main ones:

The overall designer was Sergei Kryukov, a graduate of the Moscow Higher Technical School, one of the experts sent to Germany in 1945 and a collaborator with Korolev on the R-7.

The moon race between the Soviet Union and the United States climaxed in summer 1969 when the first men landed on the moon – but there was an earlier, dramatic climax six months earlier at Christmas 1968. That time the battle was to see which country would be the first to send people around the moon and return. Although, in retrospect, there was less and less chance that the Russians would beat the Americans to a moon landing, the chances of the Russians sending cosmonauts around the moon first were very real.

By late August 1968, the Russians were still trying to achieve a successful mission of the L-1 Zond around the moon. The continued troubles with the Proton rocket must have been deeply disappointing. It was then going through its most difficult phase of development and none could have imagined that it would become, much later on, one of the world’s most reliable rockets. Although L-1 Zond missions had started as far back as March 1967 with Cosmos 146, none since then had been entirely successful. In August 1968, the Russians began to realize that time was no longer on their side. The first manned Apollo, redesigned after the Apollo fire, was due to make its first flight in October. Word came out of Washington that NASA was considering sending the second Apollo around the moon before the end of the year. It would be only the second Apollo flight and the first crew on the huge Saturn V rocket. The Russians had considered four unmanned lunar flights as essential before a manned flight: now the Americans were planning a manned flight on only the second Apollo mission, without any unmanned flights around the moon first.

As luck would have it, the same launch window that might take Apollo 8 to the moon opened for America on 21st December but much earlier in the USSR – from 7th to 9th December. This was entirely due to the celestial mechanics of the optimum launching and landing opportunities.

The government decision of 8th January 1969 to reorientate the space programme around unmanned lunar exploration and space stations did lead to a successful

programme of unmanned lunar exploration (Chapter 7: Samplers, rovers and orbiters). More important in the long term, it propelled the Soviet Union into becoming the leading country in the development of space stations. In January 1969, at the reception for the Soyuz 4-5 cosmonauts, Mstislav Keldysh had announced that space stations would be the main line of development of the programme. In October 1969, advocates of the programme cunningly slipped into a speech by Leonid Brezhnev the declaration that they were now the main line of development.

Space stations had always featured in Soviet space thinking, back to the time of Tsiolkovsky. Korolev had brought forward outline designs of a manned space station in the early 1950s, to be launched by his N-1 rocket. The first space station programme to win approval for development was a proposal put forward by Vladimir Chelomei’s OKB-52 and approved as the Almaz military space station programme (1964). This complex design made slow progress and by 1969 was still some two or three years distant. Accordingly, the decision was taken in early 1970 to combine the Almaz design of OKB-52 with Soyuz hardware developed by OKB-1 so as to construct a space station as soon as possible. Despite these hasty and makeshift origins, not to mention Chelomei’s opposition, the space station was actually built quite quickly, in only a year. It was launched in 1971 as Salyut and duly became the first manned orbiting space station, a full two years before America’s Skylab. As the moon programme encountered ever more difficulties, the Russians gave their space station programme ever more retrospective justification.

The Soviet Union’s space station programme in the early to mid-1970s was cursed with difficulties, and these certainly contributed to Mishin’s downfall as much as the moon race. The first crew to reach Salyut was able to link to the station, but not dock properly or enter the station and had to make an emergency return. In the worst-ever disaster to affect the manned programme, the three cosmonauts who flew to Salyut in June 1971 perished on their return, when a depressurization valve opened at high altitude. The next Salyut crashed on launch in July 1972.

The racing days of the moon programme echoed again in spring 1973 as the Americans at last prepared to launch their space station, Skylab. To match Skylab, the Russians prepared two space stations for launch, planning to have both of them operational and occupied at the same time. The first, which was also the first Almaz station, suffered an on-orbit engine explosion and had to be abandoned before it was manned. The second accidentally exhausted all its fuel on its first orbit and also had to be abandoned. It must have galled the Russians that America’s Skylab then went on to become such a stunning success.

The first successful space station occupation did not take place until July 1974, when Pavel Popovich and Yuri Artyukin occupied the second Almaz station. This was the first flight after the dismissal of Mishin and the first to take place on Glushko’s watch. Even then, the space station programme was to suffer many setbacks and disappointments. Soyuz 15, 23 and 25 had to come down early when their docking manoeuvres failed. The space station programme did not reach maturity until Salyut 6 (occupied 1977-82) and 7 (occupied 1982-6). Here, Soviet cosmonauts learned to live in space, pushing back the frontiers of long-distance flight to 96,139,175,185,211 and 237 days. Salyuts received regular visitors: unmanned refuelling craft and visiting missions from the socialist countries. With Mir (occupied 1986-2000), the Soviet Union built a permanent orbital station. Mir became to the Soviet programme what Apollo had been to the Americans. Only by returning to its roots in the writings of Tsiolkovsky and the other early visionaries did the programme at last find its true vocation.

The second moonbase proposal was the Zvezda one developed for Valentin Glushko by Ivan Prudnikov in 1974. The crew for the moon base would be brought there by a 31 tonne lunar expeditionary craft, or LEK in Russian. This would use direct ascent, not lunar orbit rendezvous. Once their lunar visit was complete, the three cosmonauts would blast home in their 9.2 tonne upper stage. The reentry vehicle was small, weighing 3.2 tonnes. The initial crew of the base would be three, but this would be doubled as more equipment was ferried up from Earth by Vulkan rockets. The total weight to be transported to the moon would, in the end, be around 130 tonnes, involving up to six Vulkans.

The moon base itself would have three elements: a habitation module, laboratory module and lunar rover. First, there would be a lunar habitation module, or LZhM in Russian. This was a non-returnable 21.5 tonne living and scientific area, 9 m tall, 8 m wide and with a volume of 160 m3. It would deploy solar panels able to generate 8 kW of electricity. Next was a laboratory production module, the LZM in Russian. Weighing 15.5 tonnes, this would stand 4.5m tall and have a volume of 100m3 for oxygen generation, biotechnology and physics experiments, operated by a single
cosmonaut at a time. As was the case with the Galaktika proposal, a lunar rover was an essential element. The Lunokhod would measure 4.5m wide, 8 m long and 3.5 m high, weigh 8.2 tonnes and could transport two cosmonauts up to 200 km distant at a speed of up to 5 km/hr. The rover would be able to drive on expeditions for up to twelve days at a time (a full lunar day), carrying drilling and other scientific equipment.

Valentin Glushko did not give up easily and attempted to resurrect it as Zvezda II in the 1980s. It was a scaled-down proposal, using two Energiya rockets rather than the much larger Vulkan [3]. Designed along lines similar to the N1-L3M plan of his deposed rival Vasili Mishin, two Energiyas would place a 74-tonne complex with five cosmonauts on board into lunar orbit. Three would descend to the surface for a twelve-day surface stay. Preliminary designs of the Zvezda II mothership and lander were done, both being significantly larger than the LOK and the LK. However, even Glushko must have realized that there was no prospect, at this time, that they would receive serious consideration.

The revised 95-tonne N-1 design was frozen and signed off by Korolev on 25th December 1964. There was far from unanimity on the design and several knowledge­able engineers insisted that the original 75 tonne N-1 design had been pushed beyond its natural limits, with a consequent risk of failure. The piping was a plumber’s nightmare. The launch mass was an enormous 2,700 tonnes. Although the N-1 was to be the same size as America’s Saturn V, its less efficient fuels produced a smaller payload. Even though the N-1 would follow a profile identical to Saturn V and Apollo, N-1 had the capacity to send only two cosmonauts into lunar orbit and only one down to the surface.

Although the project had first been mooted in 1956 and approved in 1960, sig­nificant resources did not begin to flow into the project until late 1964. Now the N-1 had to catch up for time lost. In his effort to do so, Korolev took two important decisions: [4]

Korolev’s philosophy was to fly rockets at the first available opportunity, so that whatever flaws might be there revealed themselves early on during a rocket’s devel­opment (most rockets were happy to oblige). Under the intense pressure to get the N-1 programme under way, Sergei Korolev and his successor Vasili Mishin minimized the ground-testing segment, a mistake the Americans did not make with the Saturn V (nor the Chinese in their programme). Korolev sometimes said in his defence that the government would not pay for proper ground-testing facilities and they would have held him up too much. Khrushchev does not agree and says that the government would never have denied Korolev proper ground-testing facilities had he asked for them – ‘especially a chief designer of Korolev’s calibre’ [8]. Chelomei’s Proton, though, presents a counter-argument. It was extensively ground-tested, but its flight record until 1972 was no better than some of Korolev’s rockets.

In an effort to compensate for possible first-stage problems, a special control system was introduced by Vasili Mishin. There was a real danger that the failure of an individual engine could jeopardize the whole mission. Accordingly, Mishin designed an engine operation control system, called KORD (Kontrol Roboti Dvigvateli) in Russian, which would shut down any badly performing engine automatically and a good engine immediately opposite, so as to preserve the symmetry of the vehicle’s thrust. KORD would also re-programme the burn so as to make up for the lost thrust. The system could tolerate the loss of four first-stage and two second-stage engines and still achieve orbit.

Compared with the Gas Dynamics Laboratory, Kuznetsov’s OKB-276 was poorly resourced and lacked any rocket engine testing facilities when it was awarded the contract for the moon rocket. Korolev was adamant about all-up testing and would never launch dummy upper stages, which he regarded as wasteful (the

Americans took a different view). Korolev argued that there was a high degree of commonality between all the NK engines and if they were tested properly individually, they should work in stages. The KORD system should be able to cope with any problems arising and the redundancy built in should protect against catastrophic failure. Against that, all engine designers will argue that exhaustive ground-testing will reveal old flaws, new flaws and be worth the investment. The preparation of the N-1 was such a huge event that the programme could not survive repeated catastrophic failures (indeed, it didn’t).

There were no ground tests of all the first-stage engines together, with or without the KORD system. But it is wrong to say that there were no ground tests at all. To the contrary, the main rocket-testing centre in the Soviet Union, at Zagorsk (now Sergeev Posad) was used for otherwise exhaustive engine tests over 1967-8. The first engine tests began in September 1967. The NK engines were erected on stands and tested for long periods. The second, third, fourth and fifth stages were tested as stages there, but not, of course, the full first stage. Granted the commonality between the engines, they may reasonably have hoped that mastering the first stage should not present serious difficulties. By the time of the first flight of the N-1, the engines had been tested for 100,000 sec on the ground.

At last, with the government resolution of August 1964, there was a sudden surge of momentum. Construction of the first N-1 pad began the next month in September. After blueprints were agreed on 30th December 1964, the government issued a decree for the construction of 16 N-1 rockets on 26th January 1965. Construction of a second, adjacent pad began in February 1966. The first N-1 hardware appeared in Baikonour in November 1966. The first pad was completed in August 1967. A mockup of the N-1 was rolled out there on 25th November 1967. This was a wise precaution, for there were many problems in trying to integrate the model with the launch pad and its fuelling systems. These took a year to sort out. Two weeks later, on 11th December, it was spotted by an American Corona photoreconnaissance satellite. The model threw a shadow across a quarter of a mile that late afternoon and set alarm bells ringing in Washington DC [9].

These pads were the largest project ever made at Baikonour. Concrete pads were built, with flame trenches gouged out of the ground underneath. Two pads were built, 500 m apart. Each had a 145 m tall rotating servicing tower and 42 m deep flame trenches. Propellants were supplied to the towers by a fuel area in between the two. To get the N-1 rocket to the pad, two railway lines were constructed from the hangar. Two diesel engines moved the empty N-1 down to the pad in parallel. Once it reached the pad, a giant crane erector moved the rocket to the vertical. The N-1 was assembled in what must have been the largest structure built at Baikonour to that point, the final assembly building. This was a huge hangar 240 m long and 190 m wide, its height ranging from 30 m to 60 m, with two high bays and three low bays [10].

The promised Lunar Exploration Council or LEK now set about its business and the N-1 passed a further design review under Keldysh on 16th November 1966. The government resolution on the moon programme of 4th February 1967 laid down a schedule for the first twelve flights of the N-1. The schedule was ambitious, to the point

of being wholly unrealistic. The plan specified an unmanned test in September 1967 (about the same time as the American Saturn V), leading to a manned lunar landing in September 1968.

The first complete N-1 rocket began construction in Samara in February 1967. Two flight models reached an advanced stage by September 1967. The first N-1 was rolled out to the pad on 7th May 1968. By then, the first N-1 launch was scheduled for later that year. Cracks were then spotted in the first-stage tanks and the whole rocket was removed over 10th-12th June. This was quite a setback to the schedule and meant that the N-1 would not fly in 1968. To continue the momentum of the programme, a mockup N-1 was at the pad from August to October for launchpad tests. To the snooping American satellites, this provided a prolonged opportunity to photograph the target during a period of good sunlight and enable the Americans to model the launcher. But even with their advanced photography, from their altitude of 150 km, the difference between a mockup and the real thing may not have been obvious.

Fifth stage (block D)

Engine

Fuel

Few people have made direct comparisons between the Saturn V and the N-1. One who has is Berry Sanders [11]. His findings were that:

• The Saturn V had a steeper trajectory than the N-1, which rolled on its side sooner.

• The Saturn V was bigger and more powerful. The first stage of the Saturn V had a fuelled weight of 2,244 tonnes, compared with the 1,875 of the N-1. On the Saturn V, the main effort at lifting was done by the hydrogen-powered second stage, while on N-1 the burden was spread evenly between the three stages. Hydrogen gave the Americans a definite advantage.

• Saturn V could put 117 tonnes into orbit, compared with 95 tonnes for the N-1. However, the N-1 paid a considerable penalty for launching into a 51° orbit from a launch site as far north as Baikonour. Had the N-1 been launched from Cape Canaveral, the N-1 could have put 104 tonnes into orbit.

Evaluating the N-1 is a difficult undertaking. At first sight, it was a disastrous rocket, for it exploded four times out of four. By comparison, the Saturn V was an engineer’s dream, for it flew 13 times and succeeded 13 times (not that all launches were incident – free, but they all made it into orbit). After the programme was over, Kuznetsov continued work on his NK-33 engine at his own expense. He decided on a duration test of 20,360 sec on a test stand. It ran perfectly. Fourteen engines logged up to 14,000 sec in other tests. Chief designer Mishin considered it the best rocket engine ever made.

Kuznetsov’s engineers received the orders from Valentin Glushko to destroy the engines in 1974, but they could not bring themselves to do it. Instead, they hid them in a shed and put a big nuclear skull-and-crossbones warning sign over them, believing that would keep prying eyes away, which it did. There the engines gathered dust for 20 years and were rediscovered, almost by accident. Visiting American engineers saw
them on a visit to Samara and could not believe their eyes: hundreds of moon rocket engines in mint order! The American Aerojet company at once bought 90 of them for $450 million and in 1995 sent them off to its Sacramento, CA plant for testing and evaluation. They worried if there would be any problems in relighting motors that had been in storage since 1974. They ran two tests – of 40 sec and 200 sec – and there were not. Aerojet’s evaluation of the engine found that it could deliver over 10% more performance than any other American engine and enthused over its simplicity, light­ness and low production costs. The hydrogen upper stage, originally planned for a later version of the N-1, became the upper stage of the Indian GSLV launch vehicle more than 25 years later.

The basic problem with the N-1 was the lack of thorough ground-testing. It was here that the much smaller resources of the Soviet Union and poor organization told against its moon programme. Rocket designers continued to underestimate the prob­lems associated with the integration of engines on stages and the resulting problems of vibration, sound, fuel flow and control. Testing engines individually, however good they are, can be a poor guide as to how they behave collectively. Even where this is done, there is no guarantee of success, as the thoroughly prepared Proton proved. The world’s space programmes are full of histories of rockets that proved extraor­dinarily difficult to tame: the American Atlas and Centaur, the Chinese Feng Bao, Europe’s Europa and India’s SLV. Even programmes that have built on the experi­ence of all that has gone before can suffer nasty surprises, like Europe’s Ariane. Having said all that, it is hard to believe that thorough ground-testing would not have stacked the odds much more in favour of the N-1. The four flight failures all had their roots in problems that could have been identified in thorough ground-testing. The real issue is not that the N-1 was a bad rocket, but that the Saturn V was so exceptionally good.

Were the rival UR-700 and R-56 proposals better? The UR-700 scheme developed by Chelomei might well have worked. In promising exhaustive ground-testing first, Chelomei rightly hit on one of the great weaknesses of Korolev’s approach. Chelomei was a superb designer but he was also slow: his Almaz space station was approved in 1964 but he did not get it ready for its first flight until 1973 and there is no reason to believe he could have built his moon rocket any sooner.

In retrospect, the Russian moon programme might have been better to go for the large RD-270 engines which Glushko began to develop. Korolev probably correctly judged that the development of the RD-270s would have required an extensive range of ground facilities and taken too long. With time against him, he calculated that it was better to go with a tried-and-tested system, even if it meant 30 engines. Korolev was always battling time to get his N-1 airborne, struggling with government depart­ments for budgets and travelling endlessly to Samara, Leningrad and Baikonour to keep things moving. Korolev may have reckoned that he had to be lucky with only one successful N-1 launch and he would then get, from the political bosses, the resources he needed to bring the project to fruition.

If the N-1 had eventually worked, then a Russian moon landing would definitely have been possible at some stage. Alternatively, if the Russians had decided not to pursue a moon landing, then they would have had available to them a large rocket able

to launch a very big space station. Several such designs were even sketched during this period. Instead of the smaller, Mir-class space station of 1986-2001, the Russians would have been able to put in orbit a large space station block long before 1980, something as large as the International Space Station. The cancellation of the N-1 not only marked the effective end of the Soviet man-on-the-moon programme but had a profound effect on the subsequent development of cosmonautics.