Thursday, October 9, 2014

An Analysis of the Failure of the Soviet Lunar Program from a Systems Engineering Perspective

Note: This is a paper I wrote for a graduate system engineering class a while ago. It's a pretty big wall of text, so be warned.

Introduction

On October 4, 1957, the Soviet Union launched the first artificial satellite, Sputnik 1, into Earth orbit months before the Americans were able to perform a similar feat. Roughly four years later, on April 12, 1961, the Soviet cosmonaut Yuri Gagarin became the first man to orbit Earth. It would be nearly a month before an American astronaut was able to make even a suborbital spaceflight. Yet despite all these early achievements, it was the Americans, not the Soviets, who would ultimately put a man on the moon. For many years, the nature of the Soviet lunar program was shrouded in secrecy. However, after the fall of the iron curtain, a wealth of new information became available, showing the true reasons why no cosmonauts ever set foot on the moon.

The reasons behind the failure of the Soviet lunar program are complex and intertwined. Failures in both leadership and engineering combined to doom any Soviet manned landing effort. From a systems engineering standpoint, there are three primary factors that can be isolated; poor management early in the program, interpersonal conflicts between the managers and engineers at the top, and finally, an insufficient testing and integration program.

Poor Management in the Early Years

The first key factor in the failure of the Soviet Lunar Program was poor management early in the program. When examining this, it is useful to compare the early history of the Soviet program to the American program. Certainly, the Apollo program was not run flawlessly, and suffered numerous setbacks of its own. Especially notable are the Apollo 1 disaster, and the combustion instability problems which plagued the F-1 engine. Both of these issues resulted in significant delays. However, from an early date, the American Lunar Program had had a set of clear goals (as set forth by Kennedy in May 1961), and was under the management of a single agency, NASA. As a result, despite “losing” to the Soviets early in the space race, the American program was able to successfully put a man on the moon by 1969.

One would think that the Soviets should have had a better chance at success than the Americans. After all, they were the first to put an artificial satellite into orbit, as well as the first to send a man into space. However, from the beginning, their lunar program was beset by issues. Even before Kennedy’s announcement, the Soviet chief designer, Sergei Korolev, had attempted to gain support for a Soviet lunar landing effort. However, the government, under Khrushchev, was uninterested, instead preferring to invest in short term efforts to generate more space “firsts”. The result was the Voshkod program, which succeeded in putting multiple cosmonauts in orbit in 1964, whereas the comparable Gemini program did not fly until 1965. However, the Voshkod was mostly a technological dead end, as it was simply a slightly modified Vostok capsule with another one or two cosmonauts wedged inside. In contrast, the American Gemini program, in addition to putting two astronauts into space, also tested important concepts needed for a lunar program, such as orbital rendezvous and docking. The Soviets would not conduct similar tests until the rollout of the Soyuz program at the end of the decade. Had the Soviets not chosen to focus on gaining prestige over the Americans, and instead developed a coherent plan early in the decade, it is likely that a version of Soyuz could have flown in 1964 or 1965 that would have conducted important tests on concepts necessary for a lunar mission. In the end, Soyuz would not fly until 1967, and even then it was beset by significant problems.

Compounding the lack of a unified plan was the poor organization of the Soviet space program in general. While the whole program was nominally under the direction of Korolev, in reality in was in the hands of numerous design bureaus, all of which competed for funding. Moreover, the vast majority of these design bureaus were not focused on space technology, but other areas, such as weaponry development. On the surface, this would not be an insurmountable problem. The American situation was not entirely dissimilar; major defense contractors such as North American or McDonnell-Douglas were responsible for much of the design work of the components of the US Space Program. However, there was a critical difference between the American and Soviet setups. In most cases on the American side, the decision on which system to use was made before construction of hardware. In the Soviet case, the decision on which system to select was often made after several design bureaus had already started construction on their various systems. This, in many cases, represented a waste of money and resources that the cash-strapped Soviet space program could ill afford.

Had everything else gone well, the Soviet space program could have overcome these issues, and possibly completed a successful lunar program. However, the poor organization of the Soviets was compounded by other factors, which scuttled their efforts to put a man on the moon. Chief among these was severe interpersonal problems between the engineers and managers at the top levels of the Soviet lunar program.

Interpersonal Issues Prevent Success

Sergei Korolev, the head of the Soviet space program during the 1950s and early 1960s, was without a doubt an excellent engineer and supervisor (for further reading on Korolev, the author recommends the biography Korolev: How One Man Masterminded the Soviet Drive to Beat America to the Moon, by James Harford). However, he did not wield sole control, instead, he shared leadership with several others. One of these people was Valentin Glushko, a noted propulsive engineer, whom Korolev strongly disliked. This was primarily because Korolev held Glushko responsible for getting Korolev sent to the Kolyma gulag in the 1930s (during the height of Stalin’s purges), and experience which nearly resulted in his death (and, in fact, may have contributed to Korolev’s demise). Additionally, Korolev held a low opinion of Glushko’s engineering skills, due to the latter’s failure to solve combustion instability issues that had plagued previous rockets, such as the R-7 (the launch vehicle for Sputnik, Vostok, and ultimately Soyuz). For instance, the American Redstone used a single A-6 engine with one combustion chamber in the first stage, while the R-7 utilized an RD-108 engine with four combustion chambers, in addition to four liquid-fuelled boosters. Despite this, Glushko’s solutions were effective (derivatives of the R-7 are still in use today), and he was without a doubt one of the best propulsion engineers in the Soviet Union.

This personal distrust only heightened the differing ideas Korolev and Glushko had about the design of the lunar rockets. Korolev believed the best option was to use cryogenic fuels, such as liquid hydrogen and liquid oxygen or a kerosene and liquid oxygen mixture (ultimately used on the Saturn V first stage). On the other hand, Glushko favored the use of hypergolic fuels such as UDMH and nitric acid, which offered lower performance, but could be stored for long periods (at this stage of development, it was still planned that the lunar rockets would have military uses).

Further compounding the issue was the presence of a third major designer, Vladimir Chelomei, who had his own ideas about how the design the lunar rockets. Chelomei also held an important advantage; he employed Khrushchev’s son. As a result, he was able to gain a political advantage, and present his ideas more effective. Enlisting the support of Glushko, and utilizing his engine designs, Chelomei was able to get his proposal, the so-called “Universal Rocket” series, selected for development. Amongst these designs was the UR-500, initially conceived as an extra-large ICBM, which would eventually mature into the Proton launch vehicle. Chelomei’s plan for the lunar rocket was a derivative of the UR-500 with an upper stage, the UR-200, mounted on top. In 1962, Khrushchev selected this plan to be developed for a circumlunar flight. By this time, the American Saturn V had been in development for five years, with the final configuration, the Saturn C-5 being selected in 1961 (the Saturn C-5 was virtually identical to the production Saturn V, aside from some slight changes in propellant load and stage diameter). By contrast, while Chelomei’s Universal Rocket was given the go-ahead for development, Korolev continued with his own design, which would ultimately evolve into the N-1.

Korolev’s considerable engineering skill, as well as the resources of his design bureau, meant that work on the N-series rockets progressed smoothly. However, his unwillingness to work with Glushko meant that he was forced to turn to other sources for his rocket’s engines. Ultimately, Korolev chose to have Nikolai Kuznetsov, a designer of turbojet engines, develop the engines for the N-1. This would be Kuznetsov’s first time working with rockets, and he and his design bureau would be forced to work from scratch. As a result, Kuznetsov’s team was not able to develop an engine comparable to the F-1 which powered the Saturn V. Instead, the result was the NK-15, which was not a poorly designed engine (its derivative, the NK-33, had the highest thrust to weight ratio of any rocket engine for many years), but it lacked power. As a result, 30 of these engines were needed to power the N-1 first stage in its final configuration; even with this many engines, the N-1 possessed a lower payload capability than the Saturn V, which utilized only five engines in its first stage.

In 1964, Khrushchev was removed from power, and replaced by Leonid Brezhnev. This resulted in a significant change in the dynamics of the politics surrounding the Soviet Lunar Program. In 1965, Korolev’s N1 and associated Soyuz spacecraft were chosen for further development, while Chelomei’s Universal Rocket system was cut off from funding. Despite this sudden victory for Korolev, significant development work still remained. Had Korolev, Glushko, Chelomei, and other Soviet engineers worked together to solve these issues, it is likely that they would not have been insurmountable. Indeed, the American Apollo program encountered myriad problems during its development, from the tragedy of Apollo 1, to lesser known issues such as the combustion instability which plagued the F-1, and issues with pogo which nearly caused the loss of a Saturn V test flight (Apollo 6).

Work progressed slowly on the N-1 through 1965, even though it had been selected over rival designs. However, Korolev’s death on 14 January 1966 completely derailed development. Korolev’s successor, Vasiliy Mishin, inherited the conflicts with Glushko and Chelomei, but lacked Korolev’s relative finesse in dealing with them. Chelomei took this opportunity to revive his own design (now known as the UR-700), siphoning off more resources from the N1. By this time, the American Saturn V was entering final tests, and would soon be flight ready. The Soviets could ill-afford to devote energy to rivalries between design bureaus. But that is exactly what happened. Even though Mishin was nominally in charge of the lunar program, Chelomei continued work on the UR-700, as well as the UR-500. Ultimately, full resources would not be devoted to the N1 until 1969, by which time the Americans had opened an insurmountable lead, already completing a manned circumlunar flight (Apollo 8), and were preparing for final spaceflight tests of the lunar module and landing techniques (Apollo 9 & 10).

The failures in communication, organization, and teamwork at the top levels of the Soviet space program were by far the most important factor in that nation’s failure to deliver cosmonauts to the moon. Had this issue been absent, or at least mitigated, it is highly possible that they could have leveraged their early lead following Sputnik and Vostok into a successful landing before the Americans. However, it was not the only factor in their failure. Ultimately, insufficient testing would prove to be the last factor in Soviet failure.

Insufficient Testing: The Final Nail in the Coffin

As the end of the 1960s approached, delays caused by political maneuvering and personal rivalries promoted an atmosphere of desperation among the Soviets. Desperate to make up time, the Soviets chose to skip tests and accelerate deployment of systems. However, this had disastrous consequences, and ultimately led to worse delays.

By far the most tragic example of this is the story of Soyuz 1 and Vladimir Komarov. As a key component of the Soviet lunar landing program, getting the Soyuz into service was a top priority. However, there were serious issues with its development. Multiple unmanned test flights in 1966 and early 1967 failed. Had the Soviets been less pressed for time, they may have opted to stop and fix the Soyuz. Instead, they decided to go ahead with a manned flight in April 1967. Soyuz’s issues were widely known among the Soviet space community; “An atmosphere of pessimism prevailed at the cosmodrome since a record 203 faults in Soyuz had been detected during the final tests.” (Lindroos 7) In fact, there are rumors that Yuri Gagarin himself lobbied to become commander of the first flight, knowing that the Soviet Union would not be willing to risk the life of a state hero such as himself. Despite this, Soyuz 1, with Komarov in command, launched on April 15. The mission suffered severe issues almost immediately, forcing the mission to be cut short to a duration of one day. After all this, disaster struck on landing; the landing parachutes failed to deploy, and Komarov was killed as the capsule impacted at high speed. He was the first in-flight casualty of spaceflight (the deaths of the Apollo 1 astronauts a few months earlier occurred during a pad test). This evidence was too strong to ignore, and manned flights of Soyuz were halted until October 1968. The orbital docking test that had been planned for the Soyuz 1 flight would not take place until January 1969. For comparison, the American Gemini 8 mission successfully docked two spacecraft in March 1966 (although that mission also suffered from issues forcing an early abort).

Just as severe were the problems associated with the N1. The design of the first stage was horribly complex due to the low power of the engines, with 30 NK-15s being used. This required a similarly complex engine control system; not a simple task using 1960s era Soviet computers. Despite this, early in development, it was decided not to build a test stand for the N1 first stage, most likely for cost and time reasons. This would have catastrophic consequences, as the first test of the stage as a unit would be an actual launch. The results of this choice would soon become apparent; during the first N1 launch, a computer fault caused the shutdown of all first stage engines less than 70 seconds into the flight, resulting the in the loss of the (fortunately unmanned) rocket.

A second failure in the Soviet test program was an insufficient vibrational test program. Unlike Cape Canaveral, where rocket components could be shipped via barge, the inland location of the Baikonur site meant that components had to be shipped by rail, subjecting them to additional vibration. Despite this, no N1 was ever assembled and subjected to static vibrational tests after shipping, as a result, the complex resonances and vibrational modes of the full rocket were never revealed. The error of this decision would be shown in the second N1 test flight, when vibrations dislodged metal fragments, causing them to be ingested into an engine oxidizer pump shortly after liftoff. The rocket fell back to the pad and exploded, causing possibly the largest non-nuclear man-made explosion in history, and the destruction of the launch pad. This failure, less than a month before Apollo 11, completely ended any faint hope of Soviet success. Two more launches of the N1 would take place before the program was cancelled in 1974. Both failed before separation of the first stage.

Conclusion

In the end, the Soviet Lunar Program failed for a variety of reasons. Chief among these was the failure of leaders in the program to work effectively as a team, although other factors, such as lack of clearly defined goals and hierarchy early in the program, and insufficient testing, also played important roles. Clearly, the Soviets had great technical skill, as shown by the successes of Sputnik and Vostok. However, their systems engineering failures denied them the ultimate prize; the hammer and sickle on the moon.

Bibliography
Harford, James . Korolev : how one man masterminded the Soviet drive to beat America to the moon. Wiley, print.
Lindroos, Marcus. "The Soviet Manned Lunar Program." n. page. Print. <http://ocw.mit.edu/courses/science-technology-and-society/sts-471j-engineering-apollo-the-moon-project-as-a-complex-system-spring-2007/readings/soviet_mand_lunr.pdf>.
"Glushko." Encyclopedia Astronautica. N.p.. Web. 24 Nov 2013. <http://www.astronautix.com/astros/glushko.htm>.
"N1." Encyclopedia Astronautica. N.p.. Web. 24 Nov 2013. <http://www.astronautix.com/fam/n1.htm>.
"Redstone." Encyclopedia Astronautica. N.p.. Web. 24 Nov 2013. <http://www.astronautix.com/lvs/redstone.htm>.
"Saturn V." Encyclopedia Astronautica. N.p.. Web. 24 Nov 2013. <http://www.astronautix.com/fam/saturnv.htm>.

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