Recently, we have celebrated the 50^th Anniversary of “One Small Step”. History records that Neil Armstrong was the First Man and that the first manned landing on the Moon was made by Armstrong and Aldrin. History also records that, had things been only slightly different, the first landing could have been made by Grissom and White, or by Conrad and Bean, or Armstrong and Lovell, or by Stafford and Cernan. There was even a scenario in which it could have been made by Armstrong and Collins.

However, there was a real possibility that the First Man could have been just that: a lone astronaut on a single-handed mission and that “one small step” could have been “Один маленький шаг” (Odin malen’kiy shag). Just as NASA had intended, originally, for the first man on the Moon to be a legendary veteran astronaut, so had the Soviet Union picked a living legend to make their own first, manned landing.

As it was, things went even more seriously wrong for the Soviet lunar landing programme that they had for NASA. The first Soyuz killed its crew, just as the first Apollo capsule did. Vladimir Komarov died trying to land Soyuz 1[1]. While NASA had serious problems with the Saturn V rocket that they managed to resolve, the Soviet space programme never did solve the problems with their equivalent of the Saturn V: the N1 rocket. However, had the N1 flown successfully, it was intended that Cosmonaut Alexei Arkhipovich Leonov would land the LK-3 descent module on the lunar surface.

While the triumphs and failures of the American space programme were played-out in front of the world’s press, the Soviet Moon programme was carried out with a degree of secrecy that allowed the N1 rocket and its problems to be hidden to that point that, for many years, it could be denied plausibly that there was even a Soviet, manned Moon programme. Many details of the N1 rocket are still not widely known.

	Saturn V	N1
Height	110.6m	105.3m
Mass	2970000	2750000kg
Stages	3	4
Thrust	3520000kg	4550000kg
Maximum payload to low Earth orbit	140 tonnes	95 tonnes
First stage engines	5, F1	30, NK-15
Launches	13	4
First launch	Apollo 4 (AS-501), Nov. 9th 1967	February 21st 1969
Last launch	Skylab-1 (AS-513), May 14th 1973	November 23rd 1972

A comparison of the main characteristics of the Saturn V and the Soviet, N1 Moon rocket. The two rockets were a similar height and mass and, although the Saturn V had the greater payload to low-Earth orbit, the N1 actually had a far superior First Stage thrust. Even if the N1 had made its maiden flight in late 1968, as the Soviet engineers hoped, it would still have been more than a year behind the Saturn V.

 

A side-by-side comparison of the Saturn V (left) and the N1 (right), with a person to scale between them. Although the upper part of the two rockets is similar, the lower part shows the radically different solutions employed in the two Moon programmes. In particular, the N1 used spherical fuel tanks, which used space less efficiently and, not having a rocket engine as powerful as the Saturn V’s F-1, used a cluster of 30, NK-15 motors.

Although the N1 was almost the same height as the Saturn V, its payload capacity was much smaller due to its less efficient second and third stages and also, to the need to carry a separate, fourth stage, to boost the capsule out of Earth orbit, unlike the Third Stage of the Saturn V, which would re-light for this manoeuvre. It would carry two cosmonauts into lunar orbit, rather than the three of the Apollo capsule. Whereas two Apollo astronauts would pass through the tunnel into the Lunar Module, leaving the Command Module pilot aboard to carry out his own programme of work and to take care of the recovery manoeuvre after the Moon landing, the two cosmonauts in the Soyuz would have no such luxury. The profile of the Moon flight was not dissimilar to Apollo, although only one of the two cosmonauts would descent to the lunar surface. Despite the fact that the Soviet, LK-3 Lunar Module, was docked with the Soyuz, there was no tunnel between the two. In a hypothetical lunar mission, Cosmonaut Alexei Leonov was expected to open the Soyuz hatch, spacewalk to the LK-3, open its hatch, board and then fly it down to the lunar surface alone. After the landing, he would fly himself back into orbit, dock and make the reverse manoeuvre to board the Soyuz for the return to Earth. Given that his first spacewalk had come close to killing him and that he had had to depressurise his suit so much to allow him to fit back in the airlock that he was suffering from symptoms of depressurisation sickness (“the bends”) when he finally made it back in, to be willing to make two spacewalks in lunar orbit, far from any possible assistance, would seem to be heroic in the extreme.

However, in other senses, the Soviet and American designers came up with similar solutions. The Soviet LK-3 lunar module looks remarkably similar to the American Lunar Module, although logically, smaller and even more similar to some of the early Lunar Module designs.

The Soviet LK-3 lunar lander. Although there are obvious differences with the Lunar Module, there are obvious signs of engineers in both programmes having come up with similar solutions to the problem of the lunar landing.

 

The one part of the Soviet lunar programme that is well known is its influence on the Apollo 8 mission. An American KH-8 spy satellite imaged the N1 on the launch pad at Baikonur on 19^th September 1968. Knowing that the N1 was being prepared for launch, presumably for a figure-of-eight free-return mission with a single astronaut, the original order of the Apollo 8 and Apollo 9 flights was changed. To avoid losing momentum in the Moon programme due to the delays in the Lunar Module, the test flight of the Lunar Module in Low-Earth orbit, that was to have been flown as Apollo 8, became Apollo 9 and Frank Borman, Jim Lovell and Bill Anders flew to lunar orbit in Apollo 8, with the launch advanced in an attempt to beat the Soviet mission to the Moon.

The spy satellite image that changed the Apollo programme. The N1 rocket is being prepared for a presumed launch before the end of 1968. Apollo 8 was re-assigned as a lunar orbital flight, instead of the intended Earth-orbit test of the Lunar Module.

Apollo 8 was an extraordinarily risky mission, with the prospects of a safe return being estimated as being as low as 50%. Had it failed, it was extremely improbable that a Moon landing could have been made in 1969. However, with the extraordinary success of Apollo 8, a Moon landing months earlier than expected became a reality as NASA followed an extremely aggressive flight schedule and led to the genuine possibility that Tom Stafford’s Apollo 10 mission could even have landed on the Moon itself.

In the end, the maiden N1 flight was delayed by multiple problems and, with the Apollo 8 astronauts safely back on Earth and the Apollo 9 flight less than two weeks away, was finally launched, unmanned, on 21^st February 1969, carrying a Zond satellite for a lunar flyby. Initially, the launch appeared to be a success. The N-1 roared into the Baikonur morning sky. The initial issue, just after the rocket cleared the tower, was the shutdown of one motor, followed rapidly by the automatic shutdown of the equivalent motor on the opposite side to keep the thrust symmetric; this, though, was a minor issue compared with what was to follow. At T+6 seconds, violent pogo – a problem that had plagued the Saturn V too – severely damaged one engine and caused a fuel leak. At T+25 seconds, further pogo ruptured a fuel line and started a fire, although, to the observers on the ground, the rocket seemed to be ascending normally still. The fire, however, damaged wiring and led to the automated control system on board sending a command, at T+68 seconds, to shut down the remaining thirty motors. A side-effect was that the shutdown caused a lock-down of systems that blocked possible manual commanding to separate the Second Stage from the stricken First Stage and fire its engines to pull it away. The rocket crashed, 52km downrange, at T+183 seconds. The one saving grace of the failure was that the launch escape system functioned perfectly and blasted the capsule to safety: had the flight been manned, the crew would have survived.

If the first flight was encouraging, if ultimately unsuccessful, the second N1 launch was an unmitigated disaster. A night launch, intended to put a Zond satellite in lunar orbit to photograph potential landing sites, no sooner had it cleared the tower than a small explosion occurred and debris started to fall from the First Stage. Twenty-nine of the thirty engines shut down at T+15 seconds. The off-axis thrust of the remaining engine tipping the rocket and causing it to fall back onto the launch pad. Investigators found that the cause of the failure was an explosion of a turbopump before launch that had, again, started a fire on board. Once again, the only small consolation was that the launch escape system functioned perfectly and that the cosmonauts would have survived the subsequent explosion of the rocket on impact. Fortunately, only 345 of the 2300 tonnes of fuel on board exploded when it crashed but, even so, the blast was equivalent to 1Kt and represented the ninth or tenth largest, non-nuclear, artificially provoked explosion in history.

This was the famous “launchpad explosion” explosion, alluded to in many histories, which ended supposedly the Soviet manned lunar programme. In reality, the Moon race had ended with the failure of the first N-1 launch, although the Soviet engineers did not give up hope finally of attaining a manned Moon landing until 1974.

Could it all have ended differently? Despite the fact that NASA had caught and then passed the Soviet programme’s successes by the end of the Gemini programme and that the N-1 development was significantly behind the Saturn V, there is a strong suspicion that, even given the incredible complexity of the N-1’s engine cluster, Sergei Korolev would have tamed the rocket and made it function. Sadly, though, the Soviet space programme’s brilliant “Chief Designer”, Korolev, had died on January 14^th 1966. Korolev’s health suffered severely after a heart attack in 1960 and he suffered several hospitalisations before his ultimate death. There are multiple versions of how he died, although the common thread is that he suffered complications – possibly uncontrolled bleeding – after (apparently, minor) surgery.

It seems no coincidence that the disasters in the Soviet space programme – the Soyuz 1 crash, the N-1 failures, … – started a year after Sergei Korolev’s death, after what had been a string of uninterrupted successes up to 1965.

The Soyuz programme resumed in October 1968 and did test, successfully, many of the elements required for a successful Moon mission, such a rendezvous, docking and crew transfer, showing how the Soviet space programme retained an interest in the Moon, even after Apollo 11 and the skills to accomplish it, were an appropriate launcher available. The triple launch of Soyuz 6, 7 and 8 in October 1969 put eight cosmonauts in orbit simultaneously, possibly to rehearse a potential multi-ship Moon flight: the aim being, apparently, to upstage Apollo success by landing multiple cosmonauts in a single, combined mission. One of the cosmonauts in the triple launch was Vladislav Volkov, who later died in the Soyuz 11 tragedy, while another was Aleksei Yeliseyev, who flew on Soyuz 5, 8 and 10[2].

A further N-1 launch, with yet another First Stage failure, occurred in June 1971, the rocket disintegrating at T+48 seconds. By this stage, though, with the launch of Salut-1, the Soviet space programme was turning its interest towards space stations in Earth orbit. A final launch, on November 23^rd 1972, just as the Apollo programme was ending, came close to success. A fire and an engine explosion led to the break-up of the N-1 just 13 seconds before staging.  Had controllers recognised the issue and commanded an early staging, it is possible that the mission could have been saved. A final launch with elements of manned, Moon-landing capability, planned for August 1974, fell victim to the cancellation of the N1 lunar programme in May of that year.

Alexei Leonov never did get a chance to leave Earth orbit. He did, though, obtain the lesser prize, of commanding Soyuz 19: better known as the Apollo-Soyuz Test Project and forerunner of the collaboration in the International Space Station. The handshake in space between Tom Stafford and Alexei Leonov was one of the happier moments of the Cold War.

The mission was a consolation prize, not only for the two astronauts either of whom could have been the first man on the Moon had things worked out differently, but also for Deke Slayton, Head of the Astronaut Office through Gemini and Apollo, who had been grounded due to a minor heart murmur shortly before his scheduled Mercury flight and for the even unluckier Vance Brand, who was rostered to fly on Apollo 18, Skylab 4 and Skylab 5, all of which were cancelled!

The Apollo-Soyuz crew.

Twenty-nine years later, Tom Stafford and Alexei Leonov met up at the Sochii Winter Olympic Games and spoke warmly of the brotherhood that they felt.

Alexei Leonov and Tom Stafford meet at the Sochii Winter Olympic Games in 2014.

Perhaps even more poignant was the meeting of the man who beat Alexei Leonov to the Moon, Neil Armstrong, and Leonov, in Tenerife in 2011, just over a year before Armstrong’s untimely death. Although not their first appearance together, it was their very last meeting, sharing reflections and reminiscences about space exploration. What stories they must have shared when talking together! Although Leonov must surely have felt perhaps a pang of regret that he never did make it to the Moon himself.

With the death of Alexei Leonov, yet another hero of the dwindling band from the race to the Moon has been lost.

[1] Komarov’s main parachute failed to deploy. The reserve parachute was deployed by him, but failed to open properly. The cosmonaut was killed by the multiple injuries sustained in the high-speed impact with the ground. Any remote chance of Komarov’s survival was extinguished when the retro-rockets ignited and the capsule was engulfed in flames that burned until the cosmonaut’s body inside was reduced to charred remains.

Vladimir Komarov’s reserve crew for the flight, who would have flown in the case of his own indisposition, was Yuri Gagarin.

[2] As Soyuz 4 and 5 flew together – Yeliseyev launched in Soyuz 5, but landed in Soyuz 4 after a crew transfer – and Soyuz 6, 7 and 8 flew together, Yeliseyev effectively flew three times in a sequence of four missions, a feat unparalleled in manned spaceflight history.