The engineers finally selected a type of storage that had first wired the primitive brains of jukeboxes in the 1950s. It was a rock-solid memory that could withstand just about anything, from impact with drunken swing dancers to rocket launches. The Apollo computer program resided, in the end, in a solid mass of wires and little magnetic rings, weighing about three pounds in all. The now-ancient-looking technology relied on a nest of wires, each of which went through some magnetic donuts (equivalent to a binary “one”), and outside other magnetic donuts (equivalent to a binary “zero”). The term “ropes” emerged in reference to the bundles of wires going in and out of these hoops.ii
The memory was difficult to build. Expert seamstresses, dubbed “rope mothers,” helped NASA literally sew the memory together into dense mats of thousands of wires and the tiny bead-like magnetic cores. A finished bank of the memory was about the size of an e-reader today, with a tiny cross-hatched weave giving it a metallic plaid appearance. Each Apollo mission would have its own specific computer program and its own specific sewing pattern. Once assembled, it could not be reprogrammed during a mission. At first, some NASA mission planners wanted a programmable computer, but over time, many saw the unalterable memory as an asset. Astronauts couldn’t mistakenly alter the spaceship’s computer code. And once the mothers finished sewing a program, engineers could run tests on it for weeks to make sure it was bug free. Since it was literally hard-wired, as memory, there was no place for new or surprising errors to emerge. Once built, it would only present errors that the mothers or engineers had themselves woven into the wires and donuts.6
Half a planet away, Sergei Korolev felt pressure similar to that of America’s early software engineers. The Soviet Union had Moon plans of their own. In late 1965, they added to Korolev’s already enormous workload by ordering him to design a manned flight that could orbit the Moon. As the calendar turned to 1966, he soldiered on despite failing health. Arriving home after his standard twelve-hour days, he would sit at the entry to his home, just past the posted guards for his apartment. There, talking over the day with his wife, he would slowly build up the strength to climb their stairs. Years of the gulag, and being dragged in and out of Stalin’s graces, had aged him.
In mid-January, he attended the Kremlin hospital for what he assumed would be minor surgery (essentially a colonoscopy). The surgeon’s work morphed into an eight-hour crisis as he encountered one complication after another in Korolev’s compromised state. In the end, the patient lost too much blood, and the Soviet Union lost the man who had engineered so many of their milestones in space. The next day, Pravda finally announced the Chief Designer’s name and published his photograph for the world to see. A formal state funeral followed in Red Square.7
For a time, their space program paced onward with Korolev’s momentum. Just a few weeks after his passing, the Soviet Union announced another first: their unmanned probe, Luna 9, had survived landing on the lunar surface. “Landed” may be too gentle a term. Luna 9 crashed into the Moon at high speed, but just before impact, it tossed off a lighter, bottom-heavy probe that rolled, righted itself like a children’s wobbly toy, and began transmitting to Earth. It sent photographs of the landscape (though unfortunately and unintentionally distorted, making all features 250 percent taller in the vertical direction). Luna 9 appeared to solve the riddle of the lunar surface when it failed to sink into a loose drift of dust, but rather sat on fairly stiff terrain. “The Moon Speaks Russian,” Soviet headlines claimed. In the spring, the program placed an unmanned probe into lunar orbit, tightening a long-distance grip on the Moon, in the way that Sputnik had for Earth.8
Again coming in second, America put their own robotic lander down in late spring. All on its own, relying in part on my father’s calculations, Surveyor I slowed from 6,000 miles per hour to just three-and-a-half miles per hour as it reached the surface. Its three little feet hit nearly simultaneously and then made one light bounce before settling to rest. It began sending a string of ten thousand photographs back to NASA’s Jet Propulsion Laboratory in California. Surveyor I was not tiny. About ten feet high and fourteen feet wide, it had solar cells, digging tools, and equipment for chemical analysis, as well as for measuring temperature and radiation on the Moon. Its gear survived the landing in good shape, and its instruments estimated a surface not unlike freshly plowed ground on Earth. All of this was great news for Apollo. Radar-guided landing on skinny metal legs worked, and the Moon, in at least a couple of spots, wasn’t covered in quicksand.9
Months later, the next Surveyor was on its way, but this one proved again that many things could go wrong on the way to the Moon. One of its engines failed, and it went into an uncontrolled tumble, spinning twice as fast as a standard vinyl record. Engineers never regained control, and the multi-million-dollar satellite, a complete loss, made a new little crater when it reached the Moon.
The prototype for a manned lander lagged behind schedule, despite the best efforts of its contractor parents, Grumman. The lander’s solitary ascent engine, charged with starting the journey home, was still acting up. Throughout the year, it kept showing unstable combustion, and NASA asked the subcontracting company charged with this engine, Bell Aerospace, to explore alternatives. But beyond that critical engine and its lift from the Moon, the lander simply suffered being last to the party. Because NASA’s decision to have a separate lander had matured fairly late in an already breakneck game, engineers played catch-up to the rest of Apollo. We can glimpse the stress of this, in a world before computer printers, as the Grumman Company struggled to complete the lander’s required diagrams and drawings for NASA. Those awaiting the drawings included Houston engineers who had to confirm it could dock properly to Apollo’s command module and Huntsville engineers who had to confirm it could fit within a metal shroud at the top of the Saturn V rocket. Lead lander designer Tom Kelly described, at the peak of activity in 1966, having to crank out four hundred large drawings each week. They improvised a plywood work surface. “The table was three feet high and about ten feet square,” Kelly wrote. “Several engineers or draftsmen worked on their hands and knees on the table, drawing directly on large sheets of vellum paper or on the white painted aluminum sheets.”10
Engineers in Houston challenged the prototype lander to see if it was steady on its feet. “It was a swing rig, kind of like a pendulum,” engineer Tom Moser relays. “We’d pull it back and let it swing and we had a release on it and would drop the model.” In this way, using a lander one-sixth of full size, engineers dropped it over and over, at different speeds and at different angles, measuring when it was likely to tumble over, when it bounced dangerously, and when it settled to a nice landing. And they awaited the chance to drop a full-scale lander in a Moon-like vacuum as well.11
Now that NASA’s big environmental chamber really worked, holding a vacuum without leaks or implosions, engineers began spacecraft tire kicking in earnest. Putting a model Apollo spacecraft in the vacuum taught engineers a great deal. For example, in the command module, engineers watched the urine exhaust lines freeze solid. They started installing extra little heaters to keep the lines unfrozen and altered mission plans to use advantageous turns toward the sun. Windows fogged over to the point of being useless, as the sealants surrounding them outgassed material to the vacuum. In short order, engineers had found more than forty design deficiencies in the main Apollo spacecraft.12
Eventually, astronauts inhabited vehicles within the vacuum chamber, risking their lives every bit as much as they might in space. Simulating the conditions of space meant death waited on the other side of a thin metal hull. More than one astronaut later confessed they felt safer on the way to the Moon than in the big test chamber. Space was absolutely reliable—one knew what to expect—but a mistake or malfunction in the chamber might create sudden changes to horrible effect.
Engineers at the Cape also ramped up efforts to give astronauts practice and familiarity with the strange missions to come. The game here was to simulate
the reality of a trip through space as realistically as possible, and NASA started from scratch.
Frank Hughes started an unlikely path into Apollo’s inner workings as he suffered through Idaho’s coldest days, wondering why he stayed in physics graduate school. Needing respite from the frigid air of a cross-campus walk, he popped into a building and found a NASA recruiting booth folding up shop for the day. He asked them to wait, but the recruiters said he was pretty late at this point. They only had one open slot left, in something called “simulations.” Hughes thought about his nearly frostbitten nose, then thought about the weather in Florida or Texas, and signed up on the spot. “I skipped the rest of that night, went home and spent the entire time filling out, with my little portable typewriter, all the information required.” NASA sent him to the Cape. Whether or not his new supervisors realized it at the time, Hughes was a perfect fit for the young field of simulations. His physics training and insatiable curiosity primed him to both understand the physical realities of an entire Moon mission (with every jerk, spin, wobble, and shadow) and also help create a convincing practice version for astronauts using a mix of optical tricks and computers.
Hughes found the Cape to be exciting, even too exciting at times. “It’s the best thing about working in Florida instead of Houston. At Houston, it’s just a white-collar job. Get down to Florida, and it’s a dangerous, highly industrial business,” he says. “Everything will either burn you, freeze you, poison you, or crush you.” He relays a particularly scary event, when a storage tank started leaking liquid oxygen late at night, near the launch pad. A dense fog of super-cool oxygen passed over a nearby roadway. “If you run liquid oxygen across asphalt, it becomes an explosive, but it becomes like a goo.” A patrolling security guard drove hesitantly into the fog, having no notion of the leak or danger. “The front end of the car just collapses in this gunk.” The man carefully stepped out of the car and took in the other-worldly mess. He slowly backed the car out and, with the running engine just inches above the explosive goo, somehow avoided a more violent ending.13
Aside from leaks, engineers occasionally needed to drain excess liquid oxygen. Relatively heavy, the boiled-off oxygen vapor usually stayed in a drainage ditch where it harmlessly dissipated, but on one occasion, a breeze lapped some of it up and over a parking lot. On this dry day, no fog formed. The oxygen invisibly surrounded a number of warm or running cars, and several of them caught fire, sending confused drivers running to safety.14
When Hughes showed up for simulations, he found an empty building and a bunch of coworkers, just as new, wondering where to start. To simulate Apollo, they would together need to understand everything about an entire mission to the Moon. They had one complete Apollo manual, such as it was in 1966, and they broke it into several segments to divide and conquer. Hughes, in particular, jumped on the fast track to becoming a generalist. “At the end of the day, everybody put the pieces back together in the book. I’m the only one that said, ‘Okay,’ and I took it home. I just sat there and read the damn book at the kitchen table.” He was unmarried and a long way from home, with no money to spend on a night out, but he loved absorbing Apollo. When he read something he didn’t understand, he went right to the experts of any particular system. “God it was great. I not only would call them and ask them how it worked, I’d say, ‘Why does it say this?’ They’d say, ‘Oh, I meant to change that.’ ” No detail was too small once Hughes drilled into an Apollo system, and the simulation team quickly built an uncommonly broad expertise.15
The eventual Apollo simulators—in time, NASA built multiple simulators for both the command module and the lunar module—included realistic cabin interiors, but these were surrounded on the outside by ungainly boxes and cables. The simulated experience of space travel married computers tracking the “ship” in space, whether it was circling Earth, circling the Moon, or somewhere in between, with a series of clever visual effects.
When an astronaut peered from the small windows of a simulator, he viewed a believable image carefully assembled using models and old-school optics. The engineers made a credible model of the Moon (to the extent that its terrain was understood at the time). This large, curved Moonscape lived upside down, with cameras panning over it from below, so that it wouldn’t accumulate earthly dust.
The simulators required a realistic star field, dialed to the correct portion of the heavens at any instant. To project an accurate spray of stars on a dark background, engineers used a “star ball”: a pitch-black sphere about two-and-a-half feet across, covered with 999 tiny steel balls, machined to be an appropriate size for each star’s respective brightness. The complete star ball then became a small globe of the heavens, creating a star field by reflection. When hit by bright light, it reflected a patch of the heavens onto a screen. The tiny steel ball bearings were even colored slightly to match the hue of each star, be it more orange or blue (see Figure 9.1).
figure 9.1 A star ball used to paint the heavens for Apollo simulators. (Photograph courtesy Frank Hughes.)
If the astronauts rotated their simulated spacecraft, the simulator itself stood still, but the star ball would spin to give the astronauts a correct view of the cosmos. “They were just incredible, gorgeous stars,” Hughes said. “So much better than anything we’ve done [since].” He notes that in a digital simulation, tiny stars eventually have to be either one pixel or two pixels, with no in-between.
When astronauts wanted to practice docking in orbit, a realistic small model of the target ship would give them a lifelike view from their windows, set against the stars. The models made for a few moments of play as well. The television series Star Trek premiered in 1966, with its optimistic (and increasingly quaint) view of a unified Earth sending explorers into the cosmos. The creator and cast once visited the Cape and sat in the simulator with an astronaut. “Okay, now we’ll turn around and dock,” their host announced. As their view rotated, they were delighted to see, instead of a lunar lander, a model of the Starship Enterprise, lovingly assembled by one of the engineers. Using the simulator, the crew “flew” the Apollo command module carefully around the starship. (Hughes claims this influenced the first studio Star Trek movie, where the captain, for no apparent reason, takes his crew on a little shuttle craft, up one side of the Enterprise and down the other.) During this visit, however, the simulated sunlight overwhelmed the dime-store plastic starship. “I looked up,” said Hughes. “I’m just on the simulator console, running the thing . . . and the Enterprise was melting. The front end was just kind of drooping down.”
Hughes and his young colleagues also pranked astronauts on occasion, using an innovation premiering in the 1960s: invisible tape. They snagged a Florida cockroach, and “we’d tape it to the lunar surface . . . about two inches away from where they’re going to land. It’s still alive, and it’s just trying to get away . . . antennas waving and the legs are darting.” Astronauts learned to shake their heads at the occasional goofiness, but their practice schedules were getting increasingly serious. NASA wanted to show the astronauts every conceivable eventuality, to give every possible problem or emergency a trial run before putting their lives at risk. Eventually, the availability of the precious simulators dominated the schedules of astronaut training.
Some parts of astronaut training took them away from the cramped simulators and even away from NASA centers. Hughes recalls taking the astronauts, with no equipment, to the middle of nowhere in Florida. After some time in a planetarium, he tested the men out of doors. “Can you still find Canopus, and Altair, and Polaris, and every one of the fifty-one stars that you had to know?” This was no sightseeing tour. If an Apollo mission lost contact with Earth, the crew would need to navigate home using their reference stars like old-time mariners in wooden ships.
Even if they learned their stars, challenges would await them. A ship orbiting Earth is always on either the bright side in sunlight or the night side in Earth’s shadow. On the bright side, the sun lighting up the atmosphere obsc
ures most of the stars. But, Hughes said, “if you get into the shadow of the Earth, you look up, and you cannot see the constellations, because there’s so damn many stars in-between all those bright ones. . . . You see more than ten thousand stars.”16 For a stargazer on Earth, the atmosphere dims the star field, hiding thousands, but once in space, assuming a clean window, a viewer takes in the unfiltered version, so complex that it looks alien. And astronauts on their way to the Moon eventually found new complications. Ice crystals (or urine crystals, in some cases) sparkled outside the Apollo spacecraft, and with no rushing air to pluck them away, the crystals would move along, maintaining orbit with the spacecraft and sparkling with reflected sunlight like so many unwelcome stars.
The year 1966 witnessed some tragic fallen stars for manned spaceflight. In February, two astronauts prepared for a Gemini mission. Hoping to check on their capsule assembly, they took a two-seater supersonic jet from Houston to St. Louis. Arriving in snowy, foggy weather, they tried to land using their instruments but crashed and died on impact, as nearby McDonnell Aircraft engineers worked to complete their Gemini spacecraft.iii
NASA nearly lost two more in a subsequent Gemini mission. The astronauts successfully docked their Gemini capsule with an unmanned target vehicle in Earth orbit.iv But before they could celebrate, the conjoined craft suddenly began spinning. Assuming the target vehicle was responsible, they separated from it, but their own capsule’s unwanted spinning only increased. The capsule’s interior began to resemble a dryer drum, tumbling one full turn every second. The astronauts’ heads banged together. Concern in Houston’s Mission Control Center steadily climbed, as the astronauts flew about Earth, moving out of communication range with one Earth station and then, many long minutes later, into range with the next station. At each step, astronauts reported faster spinning, and nothing they tried would control it. Their vision started to blur. NASA knew that, if the two men blacked out, they would probably die in orbit. And since the capsule’s radio antenna was also gyrating like crazy, communications became almost impossible. At the last instant, astronaut Neil Armstrong decided to turn off the entire primary system of thrusters. Using a secondary set normally reserved for their descent from orbit, the crew then carefully snuffed out the crazy rotations.
The Apollo Chronicles Page 18