by Dan Parry
( )
The decision to bring a second spacecraft along – with all the extra weight this implied – was one of the reasons why the Saturn V had needed to be so big. Controversial though it was, the LM was the vital component in the only viable plan to get to the Moon. When first raised, this plan was considered so risky it was barely taken seriously. It originated during the agency's first major discussions on the lunar landing and relied on concepts so ambitious they triggered one of the most emotionally charged rows in the history of NASA.
The debate arose a year before Shepard's Mercury flight, in 1960, when NASA's Space Task Group was looking for projects that could be pursued after the Mercury programme. Responsible for planning and developing manned missions, the group was led by Dr Robert Gilruth. Initially, his task was 'to put man in space and bring him back in good shape – and do it before the Soviets', but his brief later expanded. Based at the Langley Research Center in Virginia, Gilruth was a gifted aeronautical engineer who managed his team with the air of a Victorian gentleman, his reticent manner, old-fashioned values and paternal style of leadership masking his immense political acumen. Although Mercury remained the priority, Gilruth was looking towards the future. One idea involved a flight orbiting the Moon, a proposal which came to be called Apollo, after the Greek god of light. By October, staff at NASA HQ in Washington felt Apollo needed a clear objective and it was suggested the project should involve a series of manned lunar landings.5 Beginning on 5 January 1961, ideas on how one might land on the Moon were presented to the agency's senior managers, and during two days of briefings it became clear that there were a number of ways this could be done.
A popular plan, known as direct ascent, suggested launching a huge rocket and sending it directly to the Moon where it would fly all the way to the lunar surface. This idea was depicted in films such as Destination Moon (1950) and adopted by Tin Tin and other space-travelling heroes. Already NASA was working on designs for a massive booster, named Nova, that would carry enough fuel to support its payload through two launches, the first from Earth, the second from the Moon. But from the start it was clear that landing such a huge rocket tail first on the Moon contained many challenges, not least the notion of an elevator that would carry the crew down to the surface.6 Many believed it would be easier and safer to land a smaller spacecraft on the Moon, though this too brought problems. How, for example, could a small spacecraft travel all the way from the Earth to the Moon and back? During the January briefing sessions, it was suggested that a small vehicle should be launched into orbit where it should rendezvous with other rockets which would supply it with the fuel for the return trip to the Moon (no existing booster could carry the whole lot into space in one go). This idea, known as earth orbit rendezvous (or EOR), was supported by Dr Wernher von Braun, a rocket engineer from Germany, caricatured by Peter Sellers in the film Dr Strangelove.
Von Braun came to be fascinated by the prospect of space travel during his teenage years, and later pursued his interest in rocket engines by designing missiles for the German army during the 1930s. A shrewd political operator, von Braun found it expedient to join first the Nazi party and then the SS, while developing what became the V-2 rocket.7 He also permitted the use of slave labour. Twenty thousand people died at the Peenemünde and Mittelwerk plants while building the V-2, the world's first ballistic missile.8 After von Braun and his team surrendered to the American army in 1945, they were sent to the States together with examples of the V-2 and boxes of supporting documents. Continuing their work, they gave the army a leading edge in developing large liquid-fuel rocket engines, supersonic aerodynamics, and guidance and control systems. Their Redstone booster was used in America's first live nuclear missile tests (and later in the initial flights of Project Mercury). In 1958, a modified Redstone, the Jupiter-C, launched the West's first satellite, Explorer 1. Meanwhile von Braun was working on designs for a more powerful booster, named Saturn – 'the one after Jupiter'. This was intended to be able to send large payloads into Earth orbit, or smaller loads into lunar orbit. By 1959, plans for the Saturn rocket had become integral to the army's Project Horizon, a proposal for a military camp on the Moon, which was just as optimistic as the Lunex Project, the air force's dream of a lunar base staffed by airmen. In the spring of 1960, von Braun was told that he and his team were to be transferred from the army to NASA, and in July he became the director of the new Marshall Space Flight Center in Huntsville, Alabama. In this capacity he was invited to attend the landing discussions in January 1961.
The briefings led to the creation of a planning group which was set up in mid-January, more than two months before Gagarin's flight. Based at HQ and chaired by the Assistant Director of Manned Space Flight, George Low, the group looked at the various ways of landing on the Moon, particularly direct ascent and EOR. Direct ascent was favoured by influential members of the team including Max Faget, the designer of the Mercury capsule. Faget was asked to examine a third idea, involving a rendezvous not in Earth orbit but in lunar orbit, but he wholeheartedly dismissed it and the group barely returned to the subject again. Low's preliminary report9 suggested manned flights to the Moon using EOR could be possible as early as 1968, while direct ascent could become a reality between 1970 and 1971. In addition to their work on a lunar landing, the group also agreed to support a second generation of spacecraft intended to maintain a presence in space after Mercury. This programme, which evolved into Project Gemini, laid the groundwork for future missions to the Moon, as did simultaneous development of the Saturn booster, the F-1 engine and hydrogen technology.10
On 22 March 1961, NASA's senior managers discussed some of these plans with John F. Kennedy, the country's dynamic new president. A written summary, sent to the White House the next day, included references to 'manned circumlunar flight in 1967', Saturn rockets, and a landing that could be 'achieved in 1970' using Nova.11 A month later, on 11 April, George Low briefed a Congress committee on plans for a lunar landing, even though nobody had yet flown in space. To demonstrate that manned missions were possible he intended to a show a film of the successful sub-orbital flight made on 31 January by Ham the chimpanzee, but he ran out of time before the committee adjourned. That night Gagarin orbited the Earth, and by the time Low returned to Congress the country was smarting from Russia's success. Low later admitted that 'we thought it would not be in our best interests to show how we had flown a monkey on a sub-orbital flight when the Soviets had orbited Gagarin'. Under pressure, NASA managers told the Congress committee that Russia might even be aiming to land a man on the Moon in 1967, the fiftieth anniversary of the Bolshevik revolution.12 Then, just as Gagarin was getting used to his new status as an international hero, American pride was further dented by the Bay of Pigs debacle, which began just days after his triumphant flight.
Kennedy had to quickly find a way of restoring national prestige. Focused on domestic priorities, he was less than dazzled by the idea of orbital flight. But with the Cold War at its chilliest Kennedy recognised that a public show of affection towards space was necessary to score major political points. With the Russians chasing a claim for technical superiority, Kennedy was advised to beat them to it. 'This is, whether we like it or not, in a sense a race,' he told James Webb, NASA's newly appointed administrator.13 Even if Mercury succeeded in putting a man into orbit, a race towards something more ambitious in space was only just beginning. The question was, what should the prize be?
On 20 April, Kennedy sent a memo to Vice-President Johnson asking whether 'we have a chance of beating the Soviets by putting a laboratory in space, or by a trip around the moon, or by a rocket to land on the moon ... ?' Johnson replied that a manned Moon landing was far enough in the future to allow the United States the possibility of achieving it first. It was an argument supported by Gilruth, who saw the project as being so technically difficult the US and Russia would each have an equal chance of success regardless of their current position. For the moment, however, Gilruth remained preoccup
ied with the more modest objectives of the current missions. For him great relief came with the first successful Mercury flight on 5 May. Millions of TV viewers were enthralled by the first US manned rocket launch, but behind the scenes America's ambitions were already being propelled towards bigger ideas.
In deciding to back a manned landing, Kennedy gave NASA the relevant parts of a forthcoming speech proposing a flight to the lunar surface in 1967. Since they still did not know how such a mission could practically be accomplished, NASA's managers urged him to put back the date. On 25 May, Kennedy told a joint session of Congress, 'I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to Earth. No single space project ... will be more impressive to mankind or more important ... and none will be so difficult or expensive.' The question of how far Kennedy was prepared to stomach the costs involved remains a subject of debate, but publicly he needed to send the right signal. The president recognised that such an effort in such a short timeframe would require a monumental commitment on a wartime scale. 'It will not be one man going to the Moon,' he added, 'it will be an entire nation. For all of us must work to put him there.'14 Gilruth doubted it could be done in the time available.
Given a shot in the arm by the commitment from Kennedy, NASA managers commissioned studies on the various landing options. Once it was realised that a huge rocket such as Nova could never be developed within the president's deadline, and the whole idea of direct ascent was left to sink into a fug of equations. With Nova stranded on the drawing board, interest veered towards von Braun's work on EOR. Although his rockets were smaller and more feasible than the Nova, his vision of two spacecraft successfully finding each other for a safe rendezvous in space remained a daunting prospect. At least if the rendezvous failed, the astronauts could be quickly brought home.
This was a comforting thought compared to the nightmare inherent in a proposal put forward by NASA's Langley Research Center. Supported by John Houbolt, a tenacious engineer with a passion for his work, the Langley plan also involved a rendezvous in space but suggested this take place not above the Earth but three days away, above the Moon – an idea that 'horrified' Low.15 Direct, to the point of being blunt, Houbolt refused to let the idea drop. He suggested that lunar orbit rendezvous (LOR) required only a very small capsule to be sent to the surface of the Moon. Unencumbered by the resources necessary for a six-day round trip to and from Earth, the capsule would only have to fly from lunar orbit down to the surface and back again. It would then rendezvous with a bigger vehicle for the journey home. Small and lightweight, it would be far easier to land than the large spaceship envisaged in EOR, never mind the mammoth Nova. In fact, Houbolt argued, LOR was 50 per cent lighter than direct ascent. Nevertheless, the plan meant that men returning from the lunar surface would have no way of getting home if they failed to find the vehicle waiting for them. The Moon was more than 2,000 miles wide. Yet if it were difficult to find a moving target as big as this, how was anyone going to be expected to find a small orbiting spacecraft? If things went wrong, there would be no hope of rescue. Forced to contemplate the prospect of dead astronauts perpetually trapped in orbit around the Moon, in June staff at headquarters rejected the idea.16
Difficult as they were for some to accept, Houbolt's proposals were inspired by a logic that could not be dismissed. Nova was too impractical and EOR raised too many technical questions. Houbolt knew there wasn't time to pursue anything other than LOR, but for months he found there was 'virtually universal opposition – no one would accept it – they would not even study it'.17 'The critics in the early debate murdered Houbolt,'18 von Braun later remembered. Bypassing several layers of management, six days before Kennedy's announcement Houbolt had put his arguments in a letter to the second most powerful man in NASA, Robert Seamans. Kennedy's deadline only served to harden Houbolt's opinions, and in November – still facing opposition to his ideas – he wrote to Seamans again. 'Do we want to go to the moon or not?' he demanded, asking, 'why is a ... scheme involving rendezvous ostracized or put on the defensive?'19
Over time, senior figures slowly came round to Houbolt's point of view including, in January 1962, Gilruth. He had been instructed to take his Space Task Group from Virginia down to Houston and there set up a site under the new name of the Manned Spacecraft Center. Once in Houston, Gilruth's group began to look seriously at LOR, while von Braun's team at the Marshall Space Flight Center continued to study EOR. Each side sought the commitment of headquarters, and with tensions running high an argument on the subject broke out within earshot of the press while Kennedy was visiting Marshall.20 Without a decision, it was impossible to move forward. Aware of the difficulties of EOR – and of the president's deadline – in June von Braun came to accept that the only viable option was lunar rendezvous. It was the final move in the game: on 11 July 1962, NASA decided in favour of LOR. 'It is my opinion to this day,' Low wrote twenty years later, 'that had the Lunar Orbit Rendezvous mode not been chosen, Apollo would not have succeeded.'21
With Apollo free to move forward, Gilruth was now able to devote his attention to the fledgling Gemini programme, believing this would provide the experience in space-flight needed to fly to the Moon. Beyond spacesuits and extra-vehicular activities (EVAs), a pressing priority was to begin work on rendezvous techniques. Any lunar landing relying on a rendezvous in space would be impossible if Gemini failed to prove it could be done. On 3 June 1965, shortly before Ed White began the first US space walk, the commander of Gemini 4, Jim McDivitt, tried to fly alongside the abandoned upper section of their two-stage rocket. Although such a manoeuvre had never been performed before, McDivitt assumed it would be relatively straightforward. But each time he attempted to approach the rocket stage he found that it mysteriously moved further away, and amid concerns over using up fuel he was ordered to abandon the experiment. By the time Gemini 5 reached orbit two months later, new training techniques had been developed and the spacecraft was fitted with a radar system. The crew successfully flew from one point in space to another, demonstrating for the first time an ability to reach a pre-determined position in orbit.
Only through practical experience of orbital mechanics was NASA able to get to grips with the difficulties of rendezvous. McDivitt had expected to catch up with his target by firing his engine, with the intention of going faster. Actually the burn simply pushed him into a higher orbit, which left him travelling more slowly relative to anything at a lower altitude – like a spent rocket stage. With the target in sight, McDivitt ought to have slowed down. In doing so he would have become more vulnerable to the pull of the Earth's gravity, which would have taken him down to a lower – and faster – orbit. When he was in the right position he could have fired his thrusters and climbed back up to meet his target. Such logic wasn't for the faint-hearted. Once digested it was supplemented with side orders of apogee adjusts, phase adjusts, plane changes and coelliptic manoeuvres, spiced up by the differences between near-circular and elliptical orbits. In short, a successful rendezvous requires an understanding of the relationship between a spacecraft's speed and its height above the Earth (or the Moon).
While Gemini 5 proved the theory, it did not approach any target but simply completed a rendezvous with an empty point in space, following a plan designed by Buzz Aldrin. It was left to the next two missions to show that NASA could indeed perform a rendezvous as required by LOR. Relying on his basic flying skills and supported by a computer, on 15 December 1965 Mercury veteran Wally Schirra flew Gemini 6 to within one foot of Gemini 7. The two spacecraft orbited the Earth three times while flying in formation, at one point maintaining their positions so accurately that neither crew had to fire their thrusters for 20 minutes. The Russians had not yet managed to do the same thing with a similar degree of accuracy, and for the first time in the space race NASA was edging ahead.
The next stage was docking. Rendezvous involved two spacecraft finding and approaching
each other, but only by demonstrating an ability to dock could NASA show that LOR was feasible. The first test was given to Gemini 8, to be commanded by Armstrong. Neil had been part of the backup crew on Gemini 5 before becoming one of the few astronauts to be given a command position on his first flight. Approaching from behind and below, Armstrong rendezvoused with an Agena target vehicle (a converted rocket stage). After gently approaching it at three inches per second, on 16 March 1966 he completed the first successful docking. 'Outside in airless space,' Armstrong later recalled, 'there was only silence, but in the cockpit we heard a slight thud. We relaxed for the first time.'22 The final moments took place during darkness; Armstrong remembered that 'you saw stars up above, and down below you might see lights from a city or lightning embedded in thunderstorms'.23
Neil, and his pilot Dave Scott, had been warned that the Agena may have been experiencing guidance problems, and soon after docking they found they were being rolled over. They stopped the problem by using the Gemini spacecraft's own thrusters, but only when they turned the Agena off did they feel that they had the problem under control. Then it started again. Armstrong noticed that the fuel used by their thrusters had dropped to 30 per cent and it dawned on him and Scott that the problem was not with the Agena but with the Gemini. The roll reached the point where Armstrong felt that the 'stresses might be getting dangerously high', and the two spacecraft might break apart.24 He wanted to pull away from the Agena, but with dangerous levels of 'rotation in all directions' he knew he risked a collision. Eventually he was able to pull away, but the problem returned, and with the spacecraft now revolving faster than one revolution per second it was quickly becoming one of the most dangerous moments in space-flight history.
'The sun flashed through the window about once a second,' Armstrong noted. Out of radio contact with the ground, the vehicle was spinning round and round so fast that the crew, now suffering from tunnel vision, were close to losing consciousness.25 'I could tell,' Armstrong later said, 'when I looked up above me to the controls for the rocket engine that things were getting blurry.'26 He had no choice but to shut down the thrusters. Investigating the problem in the analytical style he developed as a test pilot, Neil successively fired each of the small boosters and found that one had become stuck in the 'open' position. By activating the re-entry control system he was able to fly the spacecraft safely, but according to the mission rules this action obliged him to return to Earth as soon as possible. Less than eight hours after launch, a decision was made to end the flight early. Armstrong felt frustrated and depressed at being unable to complete the mission, but his cool handling of the emergency won him much praise within NASA's higher echelons.27