Apollo: The Race to the Moon (67 page)

As for the extra twenty-four hours that the crew would have to spend in space: By this time, Tuesday morning, people were confident that the consumables could be stretched to last two and a half more days. The main problem still outstanding, the shortage of lithium hydroxide, wouldn’t be avoided by the fast return—the LEM would run out before the crew got home, no matter which burn they chose. And the slow burn still kept options open. If some additional problem developed on the way home, they could always use the remaining propellants to speed up the spacecraft and make an emergency landing in the nearest available ocean. As he talked, Reed was gratified to see Bob Gilruth, still center director at Houston and the grand old man of manned space flight, nodding in agreement with each of his points.

Kraft had reached his own opinion after thrashing out the options at a meeting of the flight directors a few hours earlier. When Deiterich and Reed had finished, Kraft summarized the options, leaving no doubt that he wanted the slower burn.

For Glynn Lunney, standing alongside Kraft, the reaction of the men in the viewing room was inspiring. The option Kraft was recommending had the obvious disadvantage of leaving the crew at risk for twenty-four hours longer than the alternatives, but there was no quibbling. Lunney: “These men who we all grew up thinking were kings, absolute tops in our business, sat in this room and said to us, ‘Look, we’re here to support you guys, and we just want to hear what’s going on and we want you to know that if there’s anything at all that you need, you just let us know.’” Then and in the days to come, Lunney recalled, “they never second-guessed, never reversed anything, never even came close to that. No cover-your-ass. The whole set of interactions was one of the most supportive and reassuring you can imagine.” The gathering quickly ratified Kraft’s choice: The Apollo 13 crew would come home more slowly, but, they hoped, more surely.

At that point, one day into the crisis, Chris Kraft and the flight directors who attended the press briefings were confidently telling the world that the astronauts were going to get back safely. Asked to reminisce years later, the flight controllers, almost to a man, said they were never in any doubt about whether they could get the crew back once it had been determined that the consumables would stretch. It is curious but true that none of them seemed to doubt that a way would be devised to use Odyssey’s lithium hydroxide supplies to stretch the LEM’s—somebody would figure out something, they assumed.

The optimism in the press briefings may have been influenced by public relations, and the confidence in the recollections may have been influenced by the passage of time. Yet it does appear that the flight controllers really were confident throughout. Gene Kranz explained it as a matter of training: “I don’t think anybody was pessimistic. Not at least on the White Team… . The training was such that, by the time you finished the process, you had the confidence that, given a few minutes, you could solve any problem. That’s all there was to it. And it didn’t matter what the size, what the magnitude, what the origin of the problem was. The fact was that you could solve any problem that came up.” Don Arabian in the MER, at least as cocky as any flight controller, felt the same way—after the first half hour, he knew that “Yeah, we can get ’em back.” It was no big deal, he said.

People who were neither controllers nor Arabian tended to be less sanguine. On Tuesday evening, a day after the explosion, journalist Robert Sherrod encountered George Low sitting in the front row of the viewing room and asked him what the chances were that they would get the crew back. Low, who knew that Sherrod was writing a book and not for the next day’s newspapers, looked at him bleakly and said, “Fair.” The problem, he explained, was that all the systems were now committed. There was no margin for anything else to go wrong. He refused to put a percentage on the odds. A little later, Sherrod mentioned Low’s response to two M.S.C. officials. They thought Low sounded optimistic compared to people they had been talking with—“Lots of guys around here wouldn’t give you a fifty-fifty chance,” one said. The next day, Sherrod encountered ASPO engineers Aaron Cohen, one of M.S.C.’s leading experts on the C.S.M., and Owen Morris, one of its leading experts on the LEM. Both were still skeptical about success. “It’s so far to go,” Cohen said. Years later, when he was about to become center director at Houston, Cohen had not forgotten his anxiety during Thirteen. Even in retrospect, it was to him a very close thing.

Despite the controllers’ optimism, which to some degree was part of their job description, the design engineers were right about how closely the margins had been shaved. A senior engineer in the Test Division, speaking just a few days after Apollo 13 had landed, said that when he heard the news about the accident he assumed the Apollo 13 crew were goners. “If you had asked [before the accident] what would happen if we lost both oxygen tanks fifty-eight hours into the mission, we’d have said, ‘Well, you can kiss those guys goodbye.’”

Each of the major participants in Apollo 13 remembered a different moment that, to him, represented ultimate crisis. For Lunney it was the final few minutes of the transfer from Odyssey to Aquarius. For Gerry Griffin and Jim Lovell, the “biggest heart-stopper” (in Lovell’s words) occurred while they were preparing for the P.C.+2 burn.

The technical problems of piloting that Lovell and Haise faced—Swigert, as command module pilot, wasn’t trained to fly the LEM—were enormous. Aquarius was about the same length as the C.S.M., but it was little more than half the weight, and the LEM’s biggest engine, the DPS, had less than half the thrust of the C.S.M.’s engine. Using Aquarius to guide the C.S.M. was like using a small car to push a limousine, but in three dimensions, with requirements for precise adjustment. It had already been a problem during the first night, when Lovell and Haise had had to maneuver the assembly into a passive thermal control (P.T.C.) mode, the slow, turning-on-a-spit spin that Joe Shea had suggested five years earlier. It became an even bigger problem on Monday afternoon, when Aquarius had to get a star sighting to prepare for the P.C.+2 burn.

Checking the alignment with star sightings was standard procedure on every flight. Even when they were functioning normally, guidance platforms tended to drift a little. Before each major maneuver, the astronauts went through a straightforward and largely automated procedure. The astronauts would select an appropriate star from their list and ask the spacecraft to find it for them. The spacecraft, consulting the I.M.U., would orient itself so that, if the platform was properly aligned, the star in question would be centered in the cross hairs of the crew’s sextant, the A.O.T. (Alignment Optical Telescope). If the star wasn’t exactly centered, the astronaut looking through the A.O.T. made the necessary adjustment to center it, and the computer entered the adjustment into the I.M.U., which then corrected itself.

When the crew of Thirteen tried to do this with the alignment it had borrowed from the C.S.M., they found that the debris from the explosion in the service module still accompanied them, reflecting light and creating a swarm of false stars indistinguishable from the real ones. They reported the problem to the ground. “A genius in Mission Control,” Lovell wrote in his account of Apollo 13, suggested using the sun instead (it was Ken Russell, the lead Guido). Not even the particles from the debris could block out a target as large as the sun.

Deiterich was unhappy with the prospect—the sun was too big for the kind of accuracy that star sightings would have given them. But no one had any better ideas, so Gerry Griffin passed along the procedure to Lovell and Haise, who tried to implement it. What followed was an example of the kind of obstacles that the crew and the ground had to surmount throughout the flight.

The LEM simply was not designed to do certain kinds of things, and getting a manual star sighting with thirty-two tons of C.S.M. hanging onto it was one of them. Whereas the star-sighting telescope in the command module was mounted so that it swiveled, the simpler one in the lunar module did not. To get a star sight to check Aquarius’s alignment before the big burn, Lovell would have to guide the whole cumbersome LEM/C.S.M. assembly manually and then hold it steady for long enough to get a fix.

By Tuesday afternoon in Houston, Lovell and Haise had gotten only a few hours of sleep and their energy reserves had been drained by more than eighteen hours of crisis. Now, without fail, they had to carry off this extremely delicate maneuver. As Lovell made their preparations to begin, Flight Gerry Griffin was so nervous that, later, he could barely make out his own handwriting in the flight log.

The ground had worked out the attitude that Lovell would have to reach. The astronauts manning the flight simulator over in Building 5 had practiced the procedures. Now it was Lovell’s turn to work the spacecraft painstakingly into the prescribed position. He was grateful for his experience on Gemini XII, when he had had to maneuver Gemini XII with the dead mass of an Agena rocket hanging on to its front, though that did not make the present job less demanding—“It was a complete learning curve, right now,” as he described it. Later, listening to a tape of the air-to-ground loop toward the end of the maneuver, Lovell was reminded of the song from My Fair Lady:

“Okay,” said Lovell. “We got it. I think we got it. What diameter was it?”

“Yes,” Haise confirmed. “It’s coming back in. Just a second.” The spacecraft had slipped out of position.

“Yes, yaw’s coming back in. Just about it.”

“Yaw is in…” At this point Lovell was struggling to hold the spacecraft steady, balancing a vehicle that kept insisting on moving. “What have you got?”

“Upper right corner of the sun…”

“We’ve got it!”

In the MOCR, the Gold Team cheered and pounded on their desks. Griffin himself would always feel a chill up his back when he recalled the moment. The crew had a valid alignment and knew how to position the vehicle for the P.C.+2 burn. For Griffin, this was the moment when he became confident that the crew was coming home alive.

For Gene Kranz, “the only dicey thing that occurred throughout all of Apollo 13” came at the conclusion of the P.C.+2 burn.

The burn itself had been an anxious event. When the White Team came into the MOCR at 4:00 Tuesday afternoon to take the first of the two shifts Kranz had assigned to it for the rest of the flight (the other would be the entry itself), many of its controllers had been working continuously for thirty hours. Astronaut Joe Engle was still in the simulator giving the team a final verification of the DPS burn procedures. The fallback procedures to use in the case of a delayed or incomplete burn were still being worked out. And Aquarius was eating up electricity at the rate of 40 amps, jeopardizing its slender margin for the trip home. From the fourth row, Chris Kraft watched the energy consumption with increasing apprehension and occasionally communicated his concern to Kranz. But there wasn’t anything Kranz could do at the moment—the LEM had to prepare itself for the burn, and that required most of its systems to be powered up.

When the time for the burn arrived, CapCom Vance Brand was so keyed up that he was watching the wrong electronic clock among the several which were counting down to various events; he called “Mark,” which was supposed to come exactly forty seconds before ignition, three minutes early. The mistake was caught and corrected. Lovell ignited the engine on schedule—it had to be done manually, for the computer was not programmed to handle a docked burn—and slowly brought the engine up through three stages to full thrust, where it continued to burn for four minutes and cut off within 130 milliseconds of the prescribed time. Thirteen was on its way back to a landing in the Pacific’s prime recovery area.

Kranz’s problem began as soon as the burn was completed, when three formidable gentlemen, each with something on his mind, converged on him at the flight director’s console. Kranz later agreed with Lunney that, for the most part, senior management played an unassuming and helpful role throughout the crisis. But, he added, “All those folks were giving us our head while we were fighting the problem and when they had pretty much no option to intervene.” With the P.C.+2 burn behind them, he suddenly discovered that “now management wanted to sit down and discuss philosophy thereafter”—“management” meaning Max Faget, Deke Slayton, and Chris Kraft.

For one of the first times since he had played through the options for dealing with John Glenn’s heat shield problem, Max Faget was deeply involved with an ongoing flight. Having examined the characteristics of the underpowered, unwieldy, damaged spacecraft that was heading homeward, he was adamant that Kranz get the spacecraft back into passive thermal control immediately. Otherwise they were in danger of overheating systems that were in the sun and freezing up propellant lines that were in the sun’s shadow. Faget was worried that unless they got into P.T.C., they would be unable to power up the command module’s systems when the time came for entry.

But getting the spacecraft into P.T.C. could take as long as two hours. Deke Slayton, director of Flight Crew Operations, wanted to get the crew to sleep, and he was supported by Chuck Berry, the head of M.S.C.’s medical office. The crew was dead on their feet; they wouldn’t be able to execute the delicate maneuvering for a P.T.C. now; they had to get some rest.

For his part, Chris Kraft was still worried about power consumption, as he had been since he had stood behind Gene Kranz on Monday night and watched the first hours of the crisis. Now that the burn was over, Kranz should get down to his 15-amps ration right away and let P.T.C. wait.

As each argued his point of view, others got into the act. The TELMUs, also worried about the power profile, were on Kraft’s side. The astronauts in Building 5, knowing the mistakes that you could make when you were cold and exhausted, were on Slayton’s side. It was a real uproar, Kranz remembered. As it happened, Kranz was one of the few who agreed with Faget.

“The flight director may choose to take any necessary action,” the rules said. It was too bad if the crew was tired, Kranz told the others, but they were going to feel a hell of a lot worse if they tried to power up the C.S.M. for entry and found out it didn’t work. They weren’t going to go to sleep; they weren’t going to power-down; they were going to put the spacecraft into passive thermal control.