Apollo: The Race to the Moon (38 page)

At T–8.9 seconds, the people in the bleachers could see an eruption of orange smoke pushing down and bouncing off the flame deflector under the launcher, then bursting out at either side. Then, a few seconds later, the flame directly under the engines turned to an incandescent white as the orange smoke billowed outward and upward, beginning to envelop the rocket. Still 501 didn’t move. Astronaut Mike Collins, who was hoping to ride a Saturn V some day, wondered momentarily whether this one was just going to sit there and be consumed in the holocaust.

The noise of the preparatory burn that had created the orange cloud was inaudible across the four miles separating the viewers from the launch site. Even as the engines went to mainstage and they saw the incandescent white flame, the sound had yet to reach them. For the people sitting in the viewing stand, the first seconds of the pyrotechnic display on Pad 39A remained eerily silent.

The main fuel valves in the S-IC’s five engines opened at slightly staggered intervals, so that neither launcher nor vehicle would have to withstand the pressure of all five engines coming to full power at the same instant. Now, as the fuel-injection pressure on each engine passed 1,060 pounds per square inch, a pressure switch sent a signal to the Instrument Unit (I.U.) high in the S-IVB stage of the stack, announcing that the thrust for that engine had reached 1.5 million pounds. At 7:00:00, the I.U., having tallied five good signals, sent a command from the vehicle through the electrical cables still connecting it to the earth, asking to be released.

At the base of the Saturn V, four hold-down arms restrained the rocket as the engines came up to mainstage power. The arms were massive, not so much to restrain the Saturn V from lifting off (the loaded weight of the Saturn V, over 6 million pounds, helped considerably to hold down the vehicle’s 7.5 million pounds of thrust) as to lessen the rebound load on the launcher if the engines were to shut down after reaching full power. In dealing with a normal liftoff, finesse was at least as important as strength, for all of the forces restrained by the hold-down arms were transmitted back into the structure of the Saturn V. To avoid putting stress on the body of the Saturn, the arms had been placed with great precision—Glover Robinson, the perfectionist engineer in charge of that operation, had used optical equipment to sight them in—and they had been designed so that there was absolutely no doubt whether they would simultaneously and instantaneously release the Saturn V upon command. Now, receiving the signal from the I.U., a helium-gas pneumatic device actuated the release, which occurred in all four arms within fifty milliseconds. If the pneumatic actuator had failed, an explosive bolt in each hold-down arm would have triggered the release.

Still the Saturn V was not entirely free of the earth. When a vehicle producing 7.5 million pounds of thrust is suddenly and completely let go, the release itself produces an abrupt shock load. Rather than shockproof the vehicle to sustain this brief, onetime jolt, its designers tethered the Saturn V to the hold-down arms with soft steel bolts. Each bolt was an inch in diameter and protruded into a bell-shaped socket attached to the Saturn V. As the rocket began to lift, the soft steel was extruded through the sockets, giving the Saturn V a lingering release and attenuating the shock.

For the first milliseconds of its ascent, the Saturn V retained its umbilical plates. These plates, which held the fuel lines and electrical connections that would permit the Launch Control Team to regain control over the Saturn V if the engines were to shut down, remained connected until after liftoff—a lesson learned from M.R.-1 seven years before. After that instant of liftoff, however, the umbilicals could come out, for there was no possibility of the Saturn V rising an inch or two and then settling uneventfully back onto the pad as the Redstone had done. Once the Saturn V had moved even fractionally, the engines had to keep going or the Saturn would fall back, collapse, and explode. As the vehicle left the pad, it tripped two liftoff switches. Whereas until that moment it had been imperative that the umbilicals remain tightly connected to the rocket, it was now equally imperative that they disconnect.

Most of the connectors holding the umbilicals into the side of the Saturn V were of a ball-release type, meaning that when a pin within the umbilical was withdrawn, the balls which had been held in place by the pin collapsed, making the connection small enough to slip out.* When the liftoff switches were tripped, the rods were pulled, the balls collapsed, and the umbilicals came free.

[* All the ball-release devices used an even number of balls. No one was quite sure why. All Don Buchanan knew was that long ago, when building the Jupiter, he had built a three-ball device, watched it work twenty-seven times in a row, then called von Braun over to demonstrate it, whereupon, on the twenty-eighth try, it hung up. Subsequently, Buchanan and his engineers had determined to their satisfaction that an odd number of balls didn’t always work, for whatever reason, whereas an even number did.]

Now the swing arms, which carried the umbilicals and had given the Cape’s workers access to the Saturn V on the pad, had to get out of the way. For the Saturn V, there were nine arms on the umbilical tower, each weighing between ten and thirty tons and designed to be swung away—on a 73-degree arc for the bottom eight, a 135-degree arc in the opposite direction for the topmost arm containing the White Room. The arms had given the Cape more trouble than any other item in the ground support equipment except the crawler. At the moment of launch, four of them were safely out of the way, already retracted. The other five were called in-flight arms, meaning that they remained in place until after the hold-down arms had released and the vehicle was already in motion. First the outermost section of each arm retracted, and then the arms themselves began to swing, accelerating rapidly to get safely away from the vehicle. As the Saturn V slowly rose into the air beside them, the arms braked abruptly to avoid smashing into the umbilical tower.

For Don Buchanan, watching from the Launch Control Center, the hold-down period had seemed endless, until he had finally begun to think that his hold-down arms must somehow have failed after all. Now, as the Saturn lifted and all five in-flight swing arms moved smoothly away from the side of the vehicle, he began to breathe again.

As the Saturn V moved off the pad, the sound finally reached across the marsh and slammed into the viewing area. It came first through the ground, tremors that shook the viewing stand and rattled its corrugated iron roof. Then came the noise, 120 decibels of it, in staccato bursts. People who were there would recall it not as a sound, but as a physical force. In the C.B.S. broadcast booth, the plate-glass window began to shake so violently that Walter Cronkite had to hold it in place with his hands as he tried to continue his commentary.

One second after lifting off, only a few feet above the launch platform, 501 began to maneuver, yawing away from the umbilical tower. For the many viewers who didn’t know this was supposed to happen, the Saturn seemed to be tilting as ominously as the Vanguards and Atlases of only a few years earlier. Even for more knowledgeable viewers, it was a nervous moment. If everything was going nicely, why interfere by trying to steer the behemoth so soon? And yet that was what the I.U. was doing, sending a preprogrammed command to the engines of the F-l, which in response were gimbaling and guiding the Saturn V away from the umbilical tower.

At the beginning, it seemed more a levitation than a liftoff—the Saturn rose so ponderously that it took more than ten seconds for it to clear the top of the umbilical tower. Then, as the Saturn got farther from the ground, the scale of the F-ls’ inferno became more fully apparent: The rocket climbed, but the trail of flames continued to billow all the way down to the base of the launcher. Not until A.S.-50l was several hundred feet off the ground did its plume of flame lift from the launch platform.

Grady Corn, sitting on the lower level of the Firing Room in Propellant Row, was down too far to see the Saturn on the pad or the actual liftoff. All he knew was that the big windows in the Firing Room were vibrating violently and plaster dust was falling loose from the ceiling of the Launch Control Center onto his console. Now, as Corn looked back up at the window, the Saturn V came into view, rising majestically against a blue sky, and Grady Corn was cheering along with the rest of the team, jubilant that he had been so wrong.

Up in the V.I.P. viewing area, von Braun yelled, “Go, baby, go!” Arthur Rudolph decided he had gotten the finest birthday present of his life. George Mueller looked pleased.

Now the I.U.’s guidance system was controlling the rocket. Massive as the Saturn V seemed to an onlooker, it would not naturally go in a straight line. On the contrary, lacking a guidance system it would have been as unpredictable as a child’s skittering balloon. The job of the guidance system was to ensure that the line of thrust of the launch vehicle was aligned with the center of mass. To that end, the guidance system checked the vehicle’s position, attitude, velocity, propellant levels, and a few dozen other variables every two seconds, and then sent messages to the four outboard F-ls (the center engine was fixed). If an onlooker could have gotten close enough to see, and if he could have ignored the scale of the machine, the behavior of the F-ls would have seemed almost delicate, as each of the four engines swiveled briefly in small, tightly controlled arcs, a few seconds here, a few seconds there, not just maintaining the Saturn V in a steady climb, but guiding it through a complex trajectory that involved programmed changes in attitude as well as continual, ad hoc adjustments to compensate for wind.

At 135 seconds into the flight, as planned, the center engine of the S-IC shut down. Fifteen seconds later, the outboard engines did the same. Then a signal from the I. U. exploded a cord of explosive primer attached around the base of the S-II, cutting away the S-IC. As the final act of its two-and-a-half-minute lifetime, the S-IC fired eight small solid-fuel retro-rockets, slowing the S-IC so that the S-II would be safely separated when its engines ignited. The great S-IC quickly lost the rest of its upward momentum and, still carrying its exquisitely crafted pumps and piping and engines, fell back to crash into the Atlantic Ocean.

High above, eight small “ullage” motors on the S-II fired for four seconds to give the S-II a burst of acceleration and settle the propellants in their tanks. Then the five hydrogen-powered J-2 engines of the second stage came to life, developing a total of a million pounds of thrust. As the S-II accelerated, a second length of primer exploded, separating the “interstage”—the sixteen-foot part of the wall of the rocket that had covered the J-2 engines and connected with the top of the first stage.

The first Saturn V continued to perform perfectly. The five J-2 engines fired for six minutes, constantly gimbaling in their delicate minuet. They too shut down precisely at the planned moment, the primer cord exploded, the retro-rockets pushed the S-II back and away, and the single J-2 engine on the S-IVB stage fired.

And still everything worked. The S-IVB fired for two minutes and twenty-five seconds, putting itself and the C.S.M. into a perfect orbit 118 miles high, with a speed of 17,400 m.p.h.

Eleven and a half minutes after it had lifted off the pad, A.S.-501 was over for the people at the Cape. It wasn’t over for the flight controllers at Houston—they would relight the S-IVB a few hours later, bringing the spacecraft back into the earth’s atmosphere at an entry speed of 25,000 m.p.h. But it was over at Cape Kennedy, where the 450 men crowded into the Firing Room had cheered again with each new report of success and were now a little groggy.

A.S.-501, which the newspapers called Apollo 4, made the headlines the next day. But there was no way that the papers could convey what men like Von Braun, Petrone, Rigell, and Corn understood. Only a few years earlier, they had been hesitantly trying, often failing, to launch rockets with a single, small engine in each stage. Today, in its first trial, they had launched a rocket the size and weight of a Navy destroyer, carrying eleven new engines, new fuels, new pumps, new technology of all kinds, and had done it perfectly. There was simply no way to explain it. They could recite how heavy it was and how powerful and how many parts it contained, but that didn’t capture it. “We fought that thing for seventeen days,” Ike Rigell said, remembering the tortuous C.D.D.T. “And then on launch day it worked. It worked beautiful.” Thinking back on it, Rigell, a matter-of-fact man not given to exaggeration, could only shake his head and say, “It was fantastic. Unbelievable.” It was that, and more. A.S.-501 had opened the way to the moon.

BOOK III. FLYING

HERE MEN FROM THE PLANET EARTH

FIRST SET FOOT UPON THE MOON

JULY 1969, A.D.

WE CAME IN PEACE FOR ALL MANKIND

—Inscription on a plaque attached to

the leg of the lunar module Eagle

Chapter 18. “We’re going to put a guy in that thing and light it”

In the fall of 1962, when Rice University gave NASA 1,000 acres of salt-grass pasture south of Houston to build the Manned Spacecraft Center, some of the university trustees thought that manned space flight might not last. A clause was inserted in the deed specifying that if space flight fizzled, Rice could reclaim the facilities.

Because the Manned Spacecraft Center (M.S.C.) was designed with this contingency in mind, NASA built a facility that was neat, innocuous, and gave no hint as to its purpose. Langley had its wind tunnels, Marshall had its massive test stand, the Cape had the V.A.B. and the towering launch complexes. M.S.C. had three dozen buildings, squares and rectangles of glass and white textured concrete, scattered around the perimeter of a central green with three irregularly shaped duck ponds. At the time the manned Apollo flights began in 1968, the trees were still scrawny saplings and the grass was patchy, burned to a dust-brown during the long summer.

Day to day, most of the work of M.S.C. was as undramatic as its surroundings. In the Center’s tallest structure, Building 2, at the end of the boulevard leading into M.S.C., Gilruth, Faget, Low, and the Center’s other senior officials worked in their suites on the upper floors—holding meetings, leafing through reports from the contractors, examining their huge charts of task schedules, and dictating memoranda. Their staffs were scattered among the other buildings, at drafting tables and computer terminals, carrying out the prosaic tasks that go into running a space program.