Moonshot: The Inside Story of Mankind's Greatest Adventure - Dan Parry (2009)
Chapter 2. CARRYING THE FIRE
Standing 363 feet tall, from a distance the Saturn V looked more like a peaceful monument than anything capable of reaching orbit. But as lightning lit up the night sky, technicians began to busily prepare the slumbering rocket for its improbable flight to the Moon. At 11pm the launch-pad team began cooling the booster's empty fuel tanks before filling them with six million pounds of propellants. The RP-1 kerosene was allowed to remain at room temperature but the pale blue liquid oxygen had to be kept extremely cold to prevent it returning to gas. It boiled at a temperature of minus 182.96°C; positively balmy compared to the liquid hydrogen that was held at minus 252.87°C. The propellants were pumped into insulated tanks resembling giant thermos flasks. As the tanks slowly began to fill, glistening chunks of ice formed on the outside of the rocket. Some of the liquid oxygen was allowed to boil off, and as the tank was replenished excess gas was released into the atmosphere to prevent a dangerous build-up of pressure. Streams of vapour rolled down towards the ground, and the rocket looked as if it were exhaling on a cold winter's morning.
The sections of the vehicle that would fly all the way to the Moon weighed more than 103,000lb (51 tons). To get them there meant first raising them off the ground, then pushing them up through the atmosphere so quickly that they reached orbit before they could fall back again. Orbit was just 100 miles from the ground; the Moon, however, was the best part of 239,000 miles away. To complete the journey the rocket would have to break free of Earth's gravity, which meant burning fuel for another five minutes and 53 seconds. All in all, to put the spacecraft on course for the Moon required such a heavy load of fuel that its weight compressed the relatively thin external skin of the booster. When fully laden, the rocket shrank by eight inches.
Once depleted, the Saturn's heavy fuel tanks had to be dropped over the Atlantic to reduce the burden on the engines. This required the rocket to be made of three separate sections. The first stage – fuel tanks, engines and all – would fall away at a height of 36 miles, at which point the second stage would take over, pushing the rocket up to an altitude of 101 miles before it too was dropped. To assist each separation process, small thrusters were placed at strategic points along the Saturn's length so that the entire vehicle carried a total of 41 rocket engines. Between them, the first two stages of the Saturn V produced enough energy to supply the city of New York for an hour and a quarter.1 After the second stage was jettisoned, the third-stage engine would then ignite, sending the spacecraft into orbit. Built by different contractors in separate locations, the three stages (together referred to as the 'launch vehicle') had been transported to Cape Kennedy and bolted together in the Vehicle Assembly Building (VAB), an enormous hangar with a floor plan covering an area of eight acres.
On top of the third stage sat an instrument unit carrying the rocket's guidance system, and above this came the three modules that would continue all the way to the Moon (together referred to as the 'spacecraft'). The lunar module was sealed inside a conical 'adapter' that rested on the instrument unit, and on this sat the cylindrical service module which carried oxygen, electrical power and other critical supplies for the command module that was attached above it. The conical command module, the principal section that would be occupied by the crew, was just 11 feet five inches high. At the very top of the stack (or 'space vehicle') was an abort rocket which was capable of pulling the command module clear of danger during the launch. The stack, consisting of nearly six million parts – a labyrinth of fuel lines, tanks, pumps, gauges, sensors, circuits and switches – was put together by more than 5,000 technicians using computer-assisted cranes and an assembly tower, which at 398 feet was taller than the Saturn itself. The entire vehicle was completed on 14 April.2
Connected by horizontal access arms, and together weighing 12 million pounds (6,000 tons), the vehicle and the tower rested on an enormous steel platform inside the VAB. The tricky thing about the VAB was that it was three and a half miles from the launch-pad. Fortunately the platform was mobile and could be collected by a vehicle and driven to where it was needed. The vehicle capable of collecting a Saturn V rocket and its accompanying tower and driving both to the launch-pad boasted a set of statistics that rivalled the booster itself. The six-million-pound 'crawler transporter' trundled along at 1mph on giant caterpillar tracks; each of its 'shoes' alone weighed a ton. More than 500 gallons of fuel were consumed during its six-hour journey along a road the width of an eight-lane motorway.3 Once the rocket was in position at Launch Complex 39A, the transporter retreated.
Specifically designed and built to accommodate the Saturn V, the pad was equipped with fuel lines encased in a protective vacuum (small leaks were stopped using tampons soaked in water that quickly froze in place). It also offered a concrete blast-room, designed to protect the crew from an exploding rocket. Built directly under the pad and capable of holding 20 people for up to three days, in an emergency the bunker could be entered via a 40-foot slide that ended in the 'rubber room'. The pad was managed by a team of technicians who reported to the Launch Control Center, an enormous blockhouse built beside the VAB, from where the overnight preparations were directed.4
At 4.15am, Neil Armstrong, Michael Collins and Buzz Aldrin were woken by the Director of Flight Crew Operations, Deke Slayton. Deke had originally been selected as one of the Mercury Seven, but after being unceremoniously grounded by a heart condition he had been moved to a management position and had never flown in space. He joined the crew for breakfast (steak), accompanied by Bill Anders from the backup crew and the artist Paul Calle, who sat sketching in a corner. Half an hour later, the astronauts began the arduous process of putting on their pressure-suits. All being well, the bulky suits could be removed a few hours into the mission, but an emergency during the early stages of the flight might mean they would have to be worn for days. The procedure began with each man rubbing a special salve on his buttocks before strapping on a condom-style device to collect urine, followed by a nappy for anything else. After attaching sensors to their chests, Armstrong, Aldrin and Collins put on 'constant wear' long-johns before being assisted into their airtight suits.
On Earth, when drawing in breath your lungs rely on the fact that their sucking action is readily met by a quantity of air heaped into the body by the weight of the atmosphere pressing down from above. Without external pressure, the lungs would struggle to function. Worse still, the natural forces within your body would no longer be held in check; blood, and other fluids, might try to burst free. Keen to avoid this, the astronauts would artificially maintain pressure within the command module, allowing them to remove their suits. These were only worn to protect the men in the event of a sudden loss of pressure during vulnerable moments, such as the initial journey into space. Each suit consisted of an inflatable bladder that allowed an artificial degree of pressure to be imposed on the body. To stop the bladder ballooning once inflated, its human shape was maintained by a web of stiff fabric, bellows, inflexible tubes and sliding cables, all of which were woven together to produce the familiar spacesuit. Two types were available: Armstrong and Aldrin wore a heavier 55lb variety capable of protecting them on the surface of the Moon, while Collins wore a lighter 35lb suit.
Once they had donned their 'Snoopy hats' (soft caps fitted with earphones and microphones), the astronauts completed the suiting-up process with the addition of a pressure helmet, a clear polycarbonate bubble. The suits were then filled with pure oxygen, which in space would allow them to replicate only a fraction of the pressure of Earth's atmosphere (3.7 psi as opposed to 15 psi). However, pressure as low as this allowed nitrogen within the body to break free of solution and collect in painful bubbles - a condition known to divers as 'the bends'. In its mildest form this effect is familiar to all of us: it's thought that 'cracking knuckles' can be attributed to bursting bubbles of nitrogen. In space, nitrogen collects in joints, particularly elbows and knees, and to prevent this the astronauts purged their body of the gas by breathing pure oxygen for more than three hours before launch. Dependent on portable supplies of pure oxygen, connected to the suit via a tube, the three men were sealed off from any physical contact with friends and colleagues waiting to bid them farewell. 'You peer at the world, but are not part of it,' wrote Michael Collins. He secretly found pressure-suits to be unsettling and even claustrophobic, so much so that he had once considered confessing all and leaving the programme.5
In the weeks before the flight, Collins had attracted almost as much press attention as Armstrong, for the fact that he would not be walking on the Moon. As the only member of the crew who would remain aboard the command module throughout the mission, he had been repeatedly asked about his fears of isolation. Despite the growing press attention he maintained a sang-froid that later earned him a reputation as Apollo 11's philosopher. Unencumbered by Neil's focus or Buzz's ambition, Michael occasionally managed to indulge a sense of detachment from his role as the command module pilot, not to mention the mission overall, and even NASA itself.
This relaxed attitude to life developed during childhood when he learned to adapt to the succession of new homes and schools that were part and parcel of life in a military family. His distinguished father, Major General James Collins, had served in the Philippines in 1911, where he had flown aboard the wing of a Wright Brothers aircraft. During an appointment to Italy as a military attaché, Michael, his fourth child, was born, in Rome on 31 October 1930. After returning to the States, the family moved to Governor's Island in New York Bay, then to Baltimore, Ohio, and Texas before being sent to Puerto Rico where they lived in a 400-year-old house. To ten-year-old Michael it seemed that no other home could offer such an immense ballroom, gardens teeming with tropical animals, and a brothel at the end of the road. Later he remembered that the girls would 'toss me money if I would talk to them but I never would'. Through his father's connections and varied postings, Michael came to acquire a broader understanding of the world than some of his NASA contemporaries.6
At school he was capable and athletic, and while he developed a love of books he also became known as a prankster. 'I was just a normal, active, troublesome kid. I liked airplanes and kites, and climbing trees and falling out of them. I didn't like school much.' He also shared Armstrong's interest in model aircraft, but for Michael it was an occasional hobby that was never as important as football and girls.
Following the family tradition, Collins attended West Point Military Academy, principally for a free education rather than to pursue an interest in the army. He could have made much of the fact that his father was a general and his uncle, a corps commander on D-Day, was now the army's chief of staff. But Michael played down his connections, to the point that after graduating in 1952 he declined to join the army at all, choosing the air force instead. After training at Nellis Air Force Base in Nevada, in 1954 Collins was sent to an F-86 fighter squadron that was soon transferred to Chambley-Bussières, a NATO base in north-eastern France.
At Chambley in early 1956 Michael met 21-year-old Patricia Finnegan. Pretty, with a vivid smile, Pat was a graduate in English who was working for the air force as a civilian. To her, Michael looked 'just as dashing, just as white-scarfy, as the others', but she was impressed by his knowledge of fine wines and French cuisine, along with his love of books and interest in the theatre. She thought he was simply 'lots and lots of fun', and above all she admired his approach to life: 'It was, and is, that everything will be OK; that everything will work out.' They married on 28 April 1957, and returned to the States a few months later.
Initially Michael had intended to complete his required four years in military service before finding something he was more suited to (his mother had suggested the State Department), but in France he found that flying had become a passion. Rather than leaving, he looked at how he might channel a restless desire for fulfilment. Collins felt the best way to get on was to become a test pilot, and he sought to accumulate the hours required by the air force's test pilot school at Edwards. Flying a variety of aircraft, Michael moved from post to post until August 1960, when the school eventually accepted him.7 As a trainee test pilot, Collins learnt to 'observe, remember, and record every last movement of a bucking, heaving, spinning plane', doing so with such proficiency that on graduation he was the only member of his class assigned to test fighter jets.
During 1961 the number of available test-flights began to dwindle and Collins found himself casting his eye further afield. Rumours that NASA was about to hire a second group of astronauts were confirmed in April 1962, and Collins, in contrast to Armstrong's dawdling, applied 'before the ink was dry on the announcement'.8 Manned space-flight was still in its infancy, and with scant information on the long-term effects of orbital missions NASA felt obliged to inspect the health of its applicants in great detail. Candidates were strapped to a table and their cardio-vascular response measured after they were jerked upright. In other tests, cold water was poured into one ear, 'eyeball pressure' was assessed, and one foot of bowel was examined using a rectal 'steel eel'. After being poked, prodded and pierced, Collins felt that 'no orifice was inviolate', the medics only giving way in order to allow the psychiatrists to take over. When asked to describe a sheet of white paper, Collins wondered what he should say. 'Perhaps I see a great white moon in it, or a picture of Mother and Dad, with Dad a little larger than Mother. Second-guessing the shrinks is not easy.'9 He scored highly in the two-month selection process, but his lack of postgraduate study and his limited test-flight experience were deemed insufficient compared to the likes of Armstrong, and ultimately he was rejected.
Just nine men were successful, including Armstrong, despite his late application. This was thanks to the support of Dick Day, a friend who had already made the move from Edwards to Houston. An expert in flight simulators, Day had been appointed as assistant director of the Flight Crew Operations Division and in this capacity he acted as secretary to the selection panel. He admitted that he and a number of others valued Armstrong's experience and wanted him to apply, so when Neil finally got round to it Day quietly slipped the late application into the pile along with the rest.10
In October 1962, while the New Nine settled into the space programme, Collins went back to Edwards, where he set about building the experience he needed. Fortunately the air force had begun to teach the science of orbital flight to hand-picked graduates of its test pilot courses, and Michael was able to spend six months acquiring the knowledge he lacked. In June 1963 NASA again asked for astronaut applications, and after another session with the 'steel eel', Collins was successful.11 Accompanied by Pat and their three children Kate, Ann and Michael junior, in October 1963 Collins headed south to Texas.
By the time the fourteen new recruits arrived in Houston, NASA was preparing to take the next step towards one day reaching the Moon. In the end there had been six Mercury flights, the longest lasting a little over 34 hours. This mission had provided valuable data, but a trip to the Moon might last anything up to two weeks and many questions had yet to be answered. Just how dangerous were the belts of radiation surrounding the Earth, which threatened to harm anyone venturing near them for too long? How long was too long? At least their location could be identified; solar flares, on the other hand, which also posed a radiation risk, were in 1963 largely unpredictable. After arriving on the Moon, would the crew and their 'lunar lander' spacecraft vanish into a thick blanket of dust, as suggested by Professor Thomas Gold of Cornell University? Other eminent scientists feared that if the lander did successfully settle on the surface, a charge of static electricity would attract so much dust that nobody would be able to see out of the windows. No-one was going to fly all the way there and back without actually stepping out of the spacecraft, but how could an astronaut be protected from the vacuum of space or the extreme temperatures of light and shade? The Moon was pockmarked by countless meteoroid craters, but just how often did meteoroids hit the surface? Continuously? Did lunar soil contain pure metallic elements that would spontaneously combust when carried by dirty boots into the pure oxygen that filled the lander's cabin?12 What should the lander even look like?
The years 1963 and 1964 were dominated by the search for answers to questions such as these, early results being drip-fed into training sessions. Since everything was geared towards a lunar landing, the training included a series of geology lectures. The Mercury veterans grumbled about learning to describe grey, lumpy stones as 'hypidiomorphic granular, porphyritic, with medium-grained grey phenochrists', but to the new recruits the lectures brought the Moon a little closer. Nevertheless, Collins sometimes found the lessons a little dull, particularly when he found himself trudging along on the back of a mule after one of the field trips. 'From supersonic jets at Edwards,' he later wrote, 'I had progressed all the way to kicking a burro up out of the Grand Canyon.'13 Between lessons, the Mercury Seven, the New Nine and the Fourteen, as the press referred to them, toured launch facilities at the Cape and inspected the new Mission Control Center in Houston. They also underwent survival training, learning to live off the land in deserts and jungles in case they came down somewhere beyond immediate reach of help. During environment training they were exposed to the noise, vibration and weightlessness of space-flight, enduring trips in what was then referred to as the 'zero-g airplane', better known today as the 'vomit comet'. As well as attending the training sessions, each astronaut also had to take on a particular area of research, representing the Astronaut Office in design meetings and test sessions. Armstrong worked on flight simulators;14 Collins was asked to help develop pressure-suits and other equipment that would be used during space walks (properly referred to as extra-vehicular activity, or EVA).
Many of the difficulties accompanying a flight to the Moon were to be explored during a series of orbital research flights, and accomplishing a successful EVA was close to the top of the list. The Mercury capsule was too small for most of this work (it was said you didn't board it so much as put it on), and by 1965 its replacement was ready to fly. Capable of accommodating two people for days at a time, the bigger Gemini spacecraft replaced Mercury's small hatch with wide hinged doors. It was intended that during the first Gemini EVA an astronaut would open the doors, stand up and simply look around. But, as before, Russian advances forced NASA to quicken its pace. On 18 March 1965, Soviet cosmonaut Alexei Leonov became the first person to leave his spacecraft during a flight. Pictures released to the international press showed him waving to the camera as he floated comfortably above the Earth. But with the Soviet secrecy that was typical of the time, the Russians did not reveal the difficulty Leonov experienced in returning to his spacecraft, Voskhod 2. While floating in space, his pressure-suit ballooned and despite an anxious struggle during which he suffered the first symptoms of heatstroke, he was unable to climb back through the airlock. After losing 12lb in body weight, Leonov was forced to partially deflate his suit – a dangerous move under any conditions. The Russians found through hard experience that returning to a spacecraft after an EVA was far from easy. Collins independently came to the same conclusion while taking part in tests aboard the zero-g aircraft. In a memo, he warned that an 'extravehicular astro requires all his strength and agility to get back inside the spacecraft'.15 It was a lesson NASA was slow to learn.
Astronaut Ed White, Collins's close friend from West Point, strenuously objected to the warnings, going on to make the whole process look easy while performing America's first EVA three months after Leonov.16 With nothing to do but enjoy himself, White found he could easily move through space using blasts of oxygen from his 'zip gun'. For more than 20 minutes he freely floated above the Earth until ordered back into his spacecraft by Mission Control. The public fell in love with Ed's boyish enthusiasm, and his triumphant accomplishment encouraged NASA to race ahead with ambitious plans for future EVAs.
Next to leave his spacecraft was Gene Cernan. Secured to the outside of the rear of Cernan's capsule was a backpack equipped with small thrusters, which he was intending to fly as if he himself were a mini spacecraft. On 5 June 1966, Cernan huffed and puffed his way back towards the backpack, known as the 'astronaut manoeuvring unit'. Lacking sufficient handrails and footholds, and breathing heavily, he suffered sunburn on his lower back after tearing the outer layers of his pressure-suit while trying to drag himself along the spacecraft's hull. Once in position, he found it so difficult to complete his task that he was forced to take frequent rests. With his visor fogging and his body beginning to overheat it was clear he was in serious trouble. As his pulse soared to around 195 beats per minute, the flight surgeon in Mission Control feared Cernan would lose consciousness. The experiment was abandoned, and after Cernan returned to the hatch Tom Stafford struggled to pull him back into his seat. Once they had repressurised the capsule Stafford felt compelled to break procedure by firing a jet of water into Cernan's face to help him recover. Had Cernan not made it back aboard the capsule, rather than cut his tether and leave him in orbit it is likely that Stafford would have strapped him to the side of the spacecraft where his body would have been cremated on re-entry.
Despite Ed White's success, NASA knew 'diddly-squat' about EVA, Cernan later wrote. His experience showed that the agency had not yet developed the training, procedures or equipment required to complete a successful EVA. There was much to learn before anyone could contemplate walking on the Moon. At least on the lunar surface it would be easier to move about. But those responsible for the development of the spacesuit, including Collins, would have to come up with a more robust design incorporating an improved cooling system.
In the meantime there were just three Gemini flights left, all would involve EVAs, and next to go was Michael.
With just three hours remaining before the launch of Apollo 11, Collins moved through the corridors of the Manned Spacecraft Operations Building, smiling at old friends and colleagues from inside his pressure helmet. By prior arrangement, one of them handed him a brown paper bag containing a gift for Guenter Wendt, the technician in charge of the launch-pad. Collins and Wendt frequently fished together, and Michael enjoyed poking fun at Guenter's claims to have caught a spectacularly large trout. In celebration of Wendt's stories, Collins decided to present him with a tiny trout that had been frozen and secured to a wooden plaque above the words 'Guenter Wendt Trophy Trout'.
Clutching his bag, Michael stepped out into the early-morning sunlight, and with the press looking on he, Neil and Buzz clambered aboard the van that would take them on the eight-mile journey to the pad. On the way, the crew crossed the Banana River where, five miles downstream, Janet Armstrong was waiting aboard a boat.17 The only one of the three wives to attend the launch (Pat Collins and Joan Aldrin had chosen to stay at home to avoid the press), along with her children Janet was accompanied by astronaut Dave Scott and Life magazine reporter Dora Jane Hamblin. Meanwhile, ashore, more than 5,000 people were taking their places in an enclosure three and a half miles from the launch-pad – deemed to be the closest point where spectators would probably escape serious injury from an exploding Saturn V. The clouds had cleared, and although it was still early the humidity was climbing and the temperature was already in the high eighties.
In the VIP stands, former president Lyndon Johnson was joined by senior NASA managers, led by Tom Paine. Beyond the Cape, millions of Americans were watching the live television coverage, among them President Nixon in Washington and hundreds of soldiers, sailors and airmen in Vietnam. Many astronauts had friends stationed in Asia, where already nearly 34,000 Americans had been killed, and some felt guilty that rather than serving alongside them they were being treated as celebrities. Gene Cernan, along with Tom Stafford, had made headlines just two months earlier following their part in Apollo 10. Cernan felt that Vietnam was his war, yet he was safely in America where he was regarded as a hero. The commander of US troops in Vietnam, General Westmoreland, had however managed to overcome any similar worries about where he ought to be and was also watching the launch from the stands. He was joined by cabinet ministers, foreign dignitaries, businessmen and half the members of Congress, together with a scattering of stars including aviation pioneer Charles Lindbergh, comedian Jack Benny, and Johnny Carson, host of NBC's Tonight Show.
Nearby around 3,500 reporters from 55 countries were gathered in the press enclosure, their numbers swollen by the throng that had witnessed the astronauts depart aboard the van. It was a moment some felt to be shaped by the hand of history, and venerable reporters like Eric Sevareid found themselves ascending into lofty rhetoric. 'You get a feeling,' Sevareid told the equally venerable Walter Cronkite, the CBS anchorman, 'that people think of these men as not just superior men but different creatures. They are like people who have gone into the other world and have returned, and you sense they bear secrets that we will never entirely know.'18
Wearing nappies and carrying a dead fish, the astronauts meanwhile were lumbering across the deserted launch-pad, still breathing through a tube. Previously they had seen it only as a hive of activity. 'Did everyone know something we didn't know?' Michael Collins later asked in jest. The only thing that exuded life was the rocket itself. Absorbing electrical power, exhaling oxygen and loaded with a million gallons of propellants, the vehicle hissed and groaned as it adjusted to its fully laden weight.
A high-speed wire lift whisked the crew up the tower to the highest swing arm, at the end of which the tiny White Room adjoined the command module. There wasn't room for all three men to board the spacecraft at once, so while Aldrin waited on the tower, Armstrong led Collins across the access arm, accompanied by Guenter Wendt. A technician with thick glasses and a caricature accent, Wendt had served as a flight engineer aboard German night fighters during the war. Nicknamed the Pad Führer by the astronauts, the term was not always used in admiration of his good-humoured though committed style of leadership. In the sterile atmosphere of the White Room, a smiling Guenter gave Neil a farewell gift in the form of a 'key to the Moon', a four-foot-long Styrofoam key wrapped in foil. In return Neil presented him with a card that had been pushed under his watchstrap by suit technician Joe Schmitt. It read: 'Space Taxi. Good Between Any Two Planets'. Clasping a rail inside the spacecraft, Neil swung his legs through the hatch and pulled himself over to the commander's couch on the left-hand side of the cabin. Behind him, Collins presented the trophy trout to Guenter19 before he too swung himself into the command module, sliding over to the couch on the right with the assistance of Fred Haise, a member of the backup crew who had spent 90 minutes preparing the cabin for launch, working his way down a 417-switch checklist.20After Buzz had taken his position in the centre couch, Schmitt connected the astronauts to the spacecraft's oxygen supply and communications system and then climbed out of the hatch, followed by Haise, who shook each man's hand as he bid them farewell.
The suggestion that 'beneath the bravado, astronauts naturally felt fear' is something of a cliché. 'What was there to be afraid of?' Buzz later asked. 'When something goes wrong, that's when you should be afraid.' For the first time man was going to the Moon, where wonderful sights were waiting to be described, but rather than give the job to a coterie of wilting poets NASA had recruited test pilot types for a reason. Through a combination of personality and training, Armstrong, Aldrin and Collins, once strapped into a cockpit, were just not the kind of people predisposed to fear. 'What would be the point?' was the way it seemed to them. Apollo 7 astronaut Walter Cunningham described how he had silently besought those around him to 'please launch and get us away from all that hand-wringing'.21 Nevertheless, there was no getting away from the fact that here was a machine designed to generate an enormous prolonged explosion. But just how controlled was it exactly? When looking for a title for his 1974 autobiography, Collins was asked to sum up space-flight in a single phrase. For him it was like 'carrying fire to the Moon and back', and in wondering how this might be done his editor received the suggestion 'carefully, that's how, with lots of planning and at considerable risk ... the carrier must constantly be on his toes lest it spill'.22
At launch, the point when a 'spill' was most likely to occur, the whole vehicle weighed more than 3,300 tons, 90 per cent of which was fuel; the command module together with the crew took up just 0.2 per cent of the overall weight. The amount of fuel, the size of the engines and the extensive safety precautions left no-one in any doubt that the crew would have to tread a fine line in terms of retaining control of the whole assembly. The prospect of watching the rocket ascending upon a stream of fire while three men sat at the mercy of its explosive force sparked a shared sense of awe among the thousands of spectators. The Saturn V was the only manned machine ever built that was powerful enough to leave not just the ground but the Earth's entire sphere of influence, the edge of which lay 186,437 miles away. As the minutes ticked by, the test of the crew's ability to control such power drew closer.
At 7.52am, technician John Grissinger closed and locked the hatch, then he, Wendt, Haise and the rest of the small 'close-out' team descended the tower, leaving the astronauts alone in the cabin.