The Apollo Chronicles
Page 22
Another 1968 film, Night of the Living Dead, envisioned a terrifying NASA blunder, as an otherwise happy probe, returning from Venus, radiated Earth and—whoops—launched a zombie apocalypse. In another writer’s mind, a probe would bring back a horrific disease, clotting the blood of any human it encountered; in 1968, Michael Crichton busily penned The Andromeda Strain.4
Turning reflective, the popular imagination seemed to ask, what did space mean for earthly life? The year witnessed the publication of Chariots of the Gods, promoting a theory (not unlike 2001) that ancient alien civilizations had visited Earth and assisted our hopeless, knuckle-dragging ancestors. Reversing a von Braun–type aspiration, this new view downgraded humanity. Maybe space was too big, too old, and too smart for us.5
As NASA prepared the second launch of a Saturn V rocket and knocked the kinks out of the lunar lander, America marched toward what became the “summer of hate.” President Johnson’s most applauded moment in his January State of the Union address was his condemning of urban violence. Instead of another pillar of the Great Society, he announced a “Safe Streets” Act.
He was also immersed in budget worries, watching the Revenue and Expenditure Control Act, including billions in budget cuts, make its way through Congress. The entire globe had financial jitters that spring. A spike in gold speculation led to an emergency decision to shutter the London gold exchange in mid-March. Western leaders hurriedly came together in Washington, D.C., trying to avoid what could become a global financial collapse.
At the end of March, the president, a steady political patron for space exploration, made a stunning announcement: he would not seek reelection. So, if NASA fulfilled Kennedy’s promise, it would happen under new leadership, for a president who’d played no part in the initial challenge.
Meanwhile, the Soviets announced a Moon-worthy feat, taking a new, heavier vehicle—unmanned but suitable for a cosmonaut—to a Moon-like distance and back to Earth. The Zond 4, at nearly the same weight as Apollo’s command module, traveled 220,000 miles away, stayed free of cabin leaks, and returned to Earth.i They were still in the race, with more missions on deck.6
The engineers collectively swallowed, blinked, and returned to preparing the second launch of a Saturn V. They worked through every detail to better Apollo’s odds and minimize risks—for astronauts and spectators alike. That spring, engineers decided to change the rocket’s ascent path. It would head eastward and out over the ocean earlier. This so-called “range safety” decision would best protect the towns of central Florida from any mishap in the first few minutes.
The lunar lander continued to suffer an awkward adolescence. Its thin, weight-saving wiring would often snap. Managers begged lander workers to be as careful and gentle as possible with their movements and even their footfalls in the fragile craft. At the same time, NASA still worried that the lander might be too heavy. As Cassetti and his group continued fine-tuning their calculations, NASA offered the lander-building contractor financial incentives to shed further pounds.
On April 4, the second unmanned Saturn V rumbled upward, rippling the sands of the Cape. Problems started right away, but not for the engineers at the Cape or in Houston. The Huntsville team received the data collected by the rocket’s instrument unit, and they got an eyeful during stage I. The ship reported a terrible pogo effect, with vibrations surging up and down the rocket as if it were backfiring. The chugging yanked the structure back and forth with a force ten times greater than Earth’s gravity itself. It lasted for about the first ten seconds and then went away. The engineers exhaled. But when they compared notes with their Houston counterparts, they learned that any pogo that violent would have severely injured human passengers. Even if astronauts could withstand such shaking, the vibrations surged past the Apollo spacecraft’s design limits, risking ruptures, breaks, or leaks.
The Saturn survived its first few minutes, discarded its troubled first stage on time, and fired the second stage engines, with five hydrogen burners leaving a fluffy white trail of water vapor. After four minutes, one of the engines turned itself off. A second later, another did the same, as if joining a sit-in. The rocket limped along with only 60 percent of its designed thrust. Engineers had thought the odds of losing two of these engines in one launch to be statistically equivalent to zero. With two side-by-side engines out of commission, the other three now provided unbalanced thrust, and the rocket risked tumbling out of control. The Saturn’s brain fought to keep the rocket on course by pivoting the three working rockets. It wasn’t a pretty path—engineers watched telemetry data plotting zigzags across the sky—but incredibly, it maintained control.7
By asking the third stage to do a little extra work, engineers could still salvage the mission and put the Apollo capsule through its paces.ii Burning this stage longer than normal put the third stage plus its Apollo craft in orbit—not the originally planned orbit but good enough for now. Then, a few hours and two orbits later, engineers moved to their next test: They would restart the third stage engine, simulating Apollo’s eventual push away from Earth and toward the Moon. Like returning to a warm car, key in hand, they sat down and cranked the ignition. Nothing—not even a chug or a puff. The engine would not restart. If the mission had contained astronauts and a lunar lander, they would have been all dressed up with nowhere to go.
Finally, given all the engine trouble, the empty Apollo capsule came in more slowly than its guidance computer expected. A software bug joined in to torment the mission. The mistaken computer code would never have affected a mission moving at proper speeds, but here, it splashed the capsule down fifty miles off target. The extra time for the capsule floating at sea emphasized yet another problem. The three-seater capsule sported a larger profile than its predecessors and with a relatively light weight, it made for an excellent sailboat. Resting on an inflatable collar, it had very little of itself below the water line, and the Apollo capsule ran with the brisk Pacific breeze. A recovery helicopter chased it down and dropped the requisite team of Navy Seals. They planned to climb onto the capsule and affix a cable, but the capsule sailed faster than the Navy Seals could swim. In later missions, the recovery team learned to take a good wind measurement and then drop the Seals in front of the capsule’s nautical tack.8
The mission left the engineers with dry mouths and knots in their stomachs: a first stage that would shake the fillings from an astronaut’s teeth, and then three separate engine failures in the upper stages. But as NASA officials prepared to brief reporters with the flight’s bad news, Apollo fell quickly and quietly to the back page of America’s concern by the end of the day.
Setting aside his new sermon late on the same afternoon, Dr. King had stepped outside his Memphis hotel room. Across the street, a fugitive convict named James Earl Ray watched King from the bathroom window of a boarding house. Earlier that year, the bigoted Ray had volunteered his time to the segregationist campaign of George Wallace. He raised a rifle to the window sill and felled Martin Luther King Jr., a man not yet forty years of age. Engineers may have looked up from their work or fielded worried calls from home, but they did not stop.
“For those of us involved in getting to the Moon, it was like we were on this little island doing our thing,” engineer Glynn Lunney said later. Raised in a Pennsylvania coal town, Lunney had joined NASA just months after graduating from college and had worked through each step of the space age, eventually as a flight director. “It’s shameful to say that, but it’s true. We were so consumed by getting to the Moon, we had little time to pay attention to anything else.” Amid national if not universal grief, engineers continued finding, fixing, and improving one technical issue after another.9
Aside from the all-consuming hours, the Apollo engineers had an understandable human choice in front of them, every day. On the one hand, America presented a dizzying set of problems that would not necessarily yield an inch to determined logic or good intentions. On the other hand, America presented them a single problem—a daunting one,
a dangerous and expensive one, absolutely—but a problem on which they found handholds, could clamber to progress, and just maybe solve. Some have admitted they had doubts, even then, about the money flowing around and over their desks, given all the problems in America. But they all wanted to finish this gargantuan job. Order, structure, selfless teamwork, and aspiration contrasted completely with the teetering world beyond their offices and laboratories.
To rub a bit of salt on NASA’s new technical problems, the Soviets put their Luna 14 probe into orbit around the Moon on April 10, and they prepared to unveil a new, more powerful rocket booster, something that could start a manned Moon mission.
Then NASA nearly lost another astronaut as he trained for a lunar landing. To give astronauts a feel for an otherworldly flight in the strange lander, engineers had improvised an ungainly, hovering machine. Operating at a military base near Houston, it used specially calibrated rockets to fight off about 85 percent of Earth’s gravity, letting the skeletal craft more or less experience a Moon’s worth of gravity in what was left. This contraption, dubbed the “flying bedstead,” malfunctioned in May. During a practice landing, it began leaking fuel and suddenly all its controls went dead. As it plummeted to the ground, the astronaut pilot, Neil Armstrong, ejected just a fraction of a second before losing his life. He maintained enthusiasm for the bedstead, however, and later claimed it provided the best practice for landing on the Moon.10 (See Figure 11.1.)
figure 11.1 The Lunar Lander Research Vehicle, aka “the flying bedstead,” during tests at NASA’s Flight Research Center in 1967. (NASA photograph.)
Meanwhile, NASA quietly started racking up a string of successes. By summertime, managers felt hope returning as determined engineers felled several major problems.
Finding and installing a pogo fix in the first stage consumed over 30,000 man-hours packed into just a couple of months. The whole assembly had resonated like a demonic organ pipe once the engines had started sputtering. The solution was ultimately a familiar one for the Huntsville team. The engines had vibrated about 5.5 times per second, while the rocket’s liquid oxygen pipes naturally shook at a too-similar 5.25 times per second.iii Engineers had to change one or the other, so that the two components couldn’t talk so easily and reinforce one another. Once again, they wouldn’t try to eliminate the mercurial pogo, but they worked to keep it from spreading around the rocket. Given the lack of time and declining budgets, they ruled out making significant changes to the pipes themselves—that would take too long and eat too much money. Instead, they added a little helium gas to the flow of liquid oxygen. (The helium was already available, since the Saturn used it to push kerosene from its fuel tanks.) Mixing helium with oxygen didn’t affect engine performance, but it dropped their vibrations from over five times per second to just about two times per second.
The three remaining engine failures (the two in the second stage, and the solitary one that wouldn’t restart in the third stage) were all in the hydrogen burners. Luckily for engineers, the first engine that failed (in the second stage) and the one engine that wouldn’t restart in the third stage showed exactly the same problem. In each case, a steel fuel line, barely half an inch across and six feet long, had ruptured, leading the engine to automatically go dormant to avoid an explosion. Both lines had ruptured in the same spot: a little accordion-like “bellows” intended to help it withstand vibrations. For a shaking line, whether from unwanted pogo or just from the violence of a launch, engineers had figured flexibility to be a plus. But why would these lines break now, when they had shown no hints of trouble during many Earth-bound tests? Detective work showed an unlikely culprit: frost. In all engine tests on Earth, natural humidity frosted the outside of the frigid line carrying liquefied hydrogen. And, in a surprise to engineers, the frost actually formed an extra layer of protection for the relatively weak bellows. During a real launch, however, the rocket had already climbed past most of the atmosphere when these engines needed to fire. With no available water vapor, no frost formed. Without frost, the jostling lines were free to snap on their way to space. Engineers revamped the fuel lines and eliminated the bellows.
But the third failed engine, the one that cut out right after its neighbor, hadn’t suffered a fuel line break. Here, engineers traced the fault back to a wiring mistake connecting second-stage engines. When the first engine suffered a busted fuel line, the faulty wiring took the neighboring engine down with it.11
By summer, von Braun, his team, and their various contractors had the engine fixes in hand. But the decade had dwindled to just eighteen short months. They had not yet put a human being on top of the mighty Saturn V, after one good launch and one nearly disastrous one. Their president and most important supporter would be leaving office, and their funding had already started to wane.
In October, a reporter asked von Braun what he was most focused on during the home stretch. “It may surprise you to hear this,” he said, “but for the last two years my main effort . . . has been following orders to scrub the industrial structure that we had built up at great expense to the taxpayer.” The once-playful rocket scientist grew more direct with the press and more frustrated with those calling the shots. Whether or not many Americans noticed the shift from bright-eyed, do-everything von Braun to a more bitter version, his supervisors at NASA headquarters noticed. And he wasn’t done with the reporter’s October question. “The sole purpose,” he continued, “seems to be to make certain that in 1972 nothing of our capability is left.” He sensed America finishing its long and expensive honeymoon with space.12
Even without these headwinds, Apollo still faced two significant problems: whether all the pounds added up to an achievable Moon journey, and whether they would ever have a vehicle to land there. In early summer, the latest lander slunk into Florida’s Kennedy Space Center, where inspectors found a bunch of the usual suspects, counting more than one hundred flaws. Windows failed under a vacuum test. Some wires had snapped during the trip from Grumman’s manufacturing plant, and many thin metal elements showed cracks again. Everyone now recognized that the lander wouldn’t debut until 1969 if it ever worked at all.13
Meanwhile, Marlowe Cassetti continued his quest to learn Apollo’s total weight, lander included. He and his staff leaned on their new teletype machine, regularly using its phone connection to the computers at the University of Houston. Having ferreted out the actual weights of the rocket, stage by stage, and each of the modules, his team computed potential flights to the Moon. And in the spring of 1968 they could see the finish line. “One of the guys that worked for me and I came in one day to finish up our analysis,” he said. “And we came in there and we found out it was Memorial Day and the whole place was shut down. We had no power in our building.” It seemed like they would have to take the weekend off.
“Wait a minute,” he thought. “I’ve got a telephone at home. I’ve got electrical power.” Why not drag the teletype home for the long weekend? The two engineers loaded the bulky beige machine into his car. “It weighs a ton,” he said. Cassetti had to sweet-talk the guards: He wasn’t trying to steal government property. “Took it home, cleaned off my dinette table, which was the closest to the [cord-bound] telephone and had this thing running, and we worked there all day until we got off our final results.”
What did they find? Was NASA a go or a no-go for the Moon?
“The results basically were, we don’t have a problem.” The alarm had sounded in 1967, as the whole enterprise looked too heavy to approach the Moon, but Cassetti found a psychological cause instead of a technical one. As good engineers will do, each sub-contractor, contractor, or NASA group wanted to give themselves just a tiny bit of wiggle room, in case they needed to add one extra bolt, one extra chip, or a little extra sealant to something heading to space. With all the conservative fudge factors added together, Apollo looked too heavy on paper, but once Cassetti and his crew extracted the actual up-to-date numbers, sans fudge, the total weight looked perfectly liftable.14
Spacecraft inspections created a new type of headache for Henry Pohl at about this time. Among his many responsibilities, he now oversaw explosives on Apollo—the planned and helpful kind. The modular spacecraft had so-called pyrotechnics, or low-power explosives used to jettison pieces or separate modules from one another at critical moments. “We took a neutron radiograph of all that hardware . . . and the explosive would show up as a black or dark image,” he said. With his more experienced men unavailable for a review meeting, he sent one of his newest employees along to examine the latest radiograph images, not expecting anything troublesome. “I just wanted the guy to have the experience,” Pohl said. “He hadn’t been with us very long.”
But in looking at the images, the employee was puzzled. “What are all of these little spaces in here, these bright spots in here?” he asked Pohl. They soon realized he was looking at gaps in the explosive ring. “And some of them were a quarter inch or longer,” Pohl recalled. “Then I came unglued. I mean, we’re getting ready for a launch, and you obviously can’t fly that junk.” To work properly, the explosive needed to form a continuous line all the way around the junction between, for instance, the command module and the service module. If the explosive charge failed to cleanly cleave the modules before re-entry, the astronauts could be stuck with dangerously tangled craft at the worst time, heading into Earth’s atmosphere. At more than twenty thousand miles per hour, the air resistance could rapidly spin the conjoined modules into a deadly tumble, and even if they stabilized, the heat shield would be stuck between the modules, unable to serve its protective purpose.