Moon Shot

by Jay Barbree

  Two wires supplying electricity to one of the fans touched. A spark flashed, and the Teflon insulation soon glowed with licks of flame. Fire quickly sped toward the tank’s oxygen supply. The intense heat caused a buildup of internal pressure which quickly exploded, shredding the tank’s structure. Its dome blew outward with the effect of a shotgun blast, destroying vital lines and systems. Apollo 13 was a ship torpedoed from within. Valves twisted shut, blocking the critical flow of vital liquids as the blast shredded everything in its path. The side of Apollo 13’s service module blew out, and the spacecraft began to die.

  Until this moment, fifty-five hours and fifty-five minutes after Apollo 13 had been launched from Cape Canaveral, Commander Jim Lovell had judged their Apollo flight as “the smoothest flight of the program.” It had been so uneventful that only a few hours before, CapCom Joe Kerwin had radioed Lovell, complaining, “We’re bored to tears down here.”

  As the side of the service module containing the astronauts’ critical fuels and rocket power exploded, the crew felt a sudden bang! Two hundred and five thousand miles from earth all hell broke loose. Linked together like a small train, the entire Apollo 13 assembly—service module, command module, and lunar landing craft—rocked violently.

  Inside the command ship Odyssey, alarm systems rang shrilly amid an eruption of flashing warning lights. Jack Swigert contacted Mission Control, his voice filled with alarm. “Houston, we’ve got a problem here.”

  Flight controllers snapped to full alert. One called out, “What the hell’s the matter with the data?”

  “We’ve got more than a problem,” another controller announced as he stared in disbelief at his monitor.

  Shift manager Sy Liebergot notified the full team. “Listen, you guys. We’ve lost fuel cell one and two pressure. We’ve lost oxygen tank two pressure.” He took a deep breath. “And temperature.”

  Temperature was vitally important. The liquid oxygen had to remain at a super-cold 297 degrees below zero, and the liquid hydrogen even colder, 423 degrees below, if the fuel cells these gases fed were to continue supplying power to the ship.

  Those were the things flight controllers knew, but no one knew yet what had happened. Were their instrument readings correct? It didn’t seem possible with a ship that had been functioning perfectly. Fred Haise, the third member of Apollo 13, said to his crewmates, “Maybe we got hit by a meteorite.”

  The entire spacecraft continued to vibrate badly. All signs indicated that Apollo 13 was breaking apart. The clamor of alarms and flashing lights continued while the crew, and Mission Control, under the direction of veteran Flight Director Gene Kranz, clung to the belief that electrical system glitches were the cause of the crisis indicated by their instruments. They couldn’t accept that Apollo 13 had flown into mortal peril.

  The astronauts reset their switches, expecting to bring everything back on line.

  It didn’t work. Swigert sent the grim message of “No joy.”

  The Apollo 13 assembly oscillated wildly, rolling and pitching up and down, swinging from side to side like a sailing vessel being tossed by hurricane winds.

  Lovell, puzzled, looked through a porthole. Thirteen minutes had passed since the jolting shock of the explosion, and he stared out at what he knew was “potential catastrophe.”

  Mission Control froze with his words. “We are venting something out into the . . . into space,” he radioed.

  The Apollo 13 commander saw his crew’s oxygen spewing away from the only tank that still held the life-sustaining gas, and he suddenly felt helplessly alone.

  The cloud erupted from the spacecraft with such force and volume that amateur astronomers on earth, two hundred and five thousand miles away, saw the expanding sphere turn into a twenty-mile-wide cocoon of gas and debris.

  Lovell felt a knot tightening in his stomach. From this moment he abandoned all thought of ever landing on the moon in the lunar module they had named Aquarius.

  All that mattered now was staying alive. They were still plunging toward the moon, their oxygen almost gone, their electrical power dying. They knew the powerful engine would no longer fire, starved as it was of the electrical energy needed for ignition and burn. Without it they couldn’t get into orbit about the moon. More importantly, without it they wouldn’t be able to get home.

  Without some kind of miracle they would be marooned in an orbit that would take them hundreds of thousands of miles away from the earth.

  Apollo 13 was in its death throes.

  If Lovell and his crew were to survive, Mission Control had just hours to perform calculations and make engineering recommendations that would normally have required weeks.

  Gene Kranz immediately set to calming his shocked team. “Okay, now let’s everybody keep cool,” he announced. “We’ve got the LM still attached. The LM spacecraft is still good, so if we need it to get back home . . . ” His voice trailed away for an instant before his mind snapped back to full alert. “Let’s solve the problem, but let’s not make it worse by guessing.”

  His words pulled the team together barely in time. Minutes later the second power system aboard Apollo began to fail. The second oxygen tank, damaged in the explosion, began losing pressure.

  It was bad, and it was going to get worse. The ship would become a lifeless derelict and its crew doomed unless they could retain the electrical power that was draining away.

  Liebergot and Kranz instructed Lovell and his crew to start powering down their ship immediately. Reduce to the absolute bare minimum whatever they needed to keep alive and retain communications with Houston.

  There wasn’t a moment to lose.

  Kranz’s team maintained a steady exchange with Apollo 13. Another group in Houston ran to telephones to call leaders and specialists. Chris Kraft, now the deputy director of the Manned Spacecraft Center in Houston, was in the shower when the phone rang. He threw clothes onto his still wet body and broke all speed laws driving to the control center. He went to Kranz’s console on a dead run.

  Kranz didn’t mince words. “We’re in deep shit,” he told his mentor.

  Alan Shepard and Deke Slayton were in their respective offices, buried in paperwork, each with an ear tuned to the squawk boxes carrying the running conversations between CapCom and Apollo 13. The call from Swigert brought them upright. By the time Swigert finished that one brief “Hey, Houston, we’ve got a problem here,” both men tore out of their offices and headed for Mission Control.

  Deke hit the control room slightly before Alan. “The damn ship sounds like it’s coming apart,” Deke told him.

  “Let’s not waste any time,” Alan nodded. “Better round up the guys for the simulators.”

  “Good, let’s go.”

  During every mission a group of astronauts was always kept on standby in the event something went wrong. Their task was to learn the problems and immediately start working out solutions in the simulators that duplicated the craft in space.

  Alan and Deke realized quickly that this was going to be a bitch to solve. Shepard put astronauts in both the command and lunar module simulators. The teams settled in to study the emergency, and Alan couldn’t help thinking that this could have been his flight. He’d fought to get Apollo 13. It could just as easily have been him, Ed Mitchell, and Stu Roosa up there, hanging to survival by a thread.

  Shepard was also a realist and knew that if they failed to bring the crew of Apollo 13 home alive, the chances of any future moon missions would be seriously jeopardized.

  Gene Kranz, Chris Kraft, Slayton, and Shepard considered the options. They could go for a direct abort, turning Apollo 13 around so that the main engine could be fired to reverse the direction of the spaceship’s path toward the moon. Shepard had been living with the Apollo systems now for months. “It’s too risky,” he said, countering the idea. “From what we’ve seen, electrical power is almost gone. The chances are the engine won’t even ignite and, even if it did, we can’t be sure of a long burn.”

  Kra
nz agreed. Their best course was to keep 13 on its way, let the ship loop around the moon, and start the swing back to earth. On the first three lunar flights, Apollo 8, Apollo 10, and Apollo 11, the spacecraft had been programmed so that the final engine burn launched the ship into a “free return trajectory.” Once the craft looped around the moon, it would be on the correct course for its return trip to earth. No additional engine firings would be required. If the astronauts on those missions had run into propulsion problems, all they would have had to do was to sit tight and wait out the ride, knowing their course for home was already set. While the “free return trajectory” minimized the chances that the Apollo craft would go off the course required for successful reentry, it also limited NASA’s options in selecting launch dates and landing sites on the moon. With Apollo 12 NASA had tried something different; the spacecraft burned its final stage for a “hybrid free return”—the ship would still loop around the moon before swinging back toward earth, but a subsequent engine burn would be needed to put the capsule on the course necessary for a successful reentry.

  Flight controllers had known the “hybrid free return” increased the odds for problems, but NASA had judged the added flexibility in selecting launch dates and in picking landing sites worth the risk.

  It had worked fine on Apollo 12, but the same hybrid moon loop could be a disaster for Apollo 13. On their current path the three astronauts would be pulled by lunar gravity into a safe whip around the moon and sent back toward earth. Except that they’d miss the planet by four thousand miles.

  Deke scratched his head. “Looks like we better have a good burn with the LM, then.”

  They all shared the same question. Could the undamaged lunar module engine, with only half the power of the main service module power plant, have enough energy to “push” the combined weight of the command, service, and lunar modules onto the course needed for an accurate return?

  The guidance officer calculated the exact velocity needed to correct the free-return path. He determined the burn time and angle data, which were sent to the astronaut crews in the simulators. They set up the simulated burn, fired the engine, and checked the resulting speed and direction. Then they did it again. Finally one astronaut held up a thumb. “They can do it,” he said simply.

  While these calculations were being made and the simulator tested, the question of the survival of the Apollo 13 crew became critical. Oxygen and power bled from the dying ship.

  Exactly fifty-one minutes after Apollo 13’s service module exploded, Gene Kranz turned to those gathered in mission control. “Two hours from now, unless we come up with something that’s never been done before, those guys are going to be in a derelict ship. Except for three short-life batteries and their reserve oxygen supply. And we can’t use them. They must save them for reentry.”

  CapCom Jack Lousma started to relay the message. But Swigert got on the radio first, asking about the oxygen status in Odyssey.

  “Oxygen is slowly going down to zero. We’re starting to think about the LM as a lifeboat,” Lousma informed him.

  “That’s something we’re thinking about, too,” came the reply from Swigert.

  Flight Director Glynn Lunney and his team relieved Kranz and moved into the Mission Control trenches. The decision to transform Aquarius, the lander, into the first space lifeboat would be his to make. There wasn’t much to talk about. Aquarius was the only chance those three men had.

  The astronauts in the simulators worked furiously to come up with answers to new questions. Lovell and his crew had to shut down Odyssey. Not kill everything in the command module, but put it into a form of hibernation so that it could later be restored to life for reentry. At the same time they had to power up Aquarius without using electrical power from either the command or service modules. It had never been done before.

  “It looks like we’ve got about eighteen minutes,” a controller said. “The last fuel cell is going fast.”

  Lovell and Haise pulled themselves through the connecting tunnel into Aquarius. The landing module was designed to transport two men to the lunar surface and then to launch them to rendezvous with the command module. Under ordinary circumstances it would be called on to perform for approximately forty hours. The module now needed to serve as the astronauts’ home. And somehow its systems must be extended to support three men for nearly four days of an earthbound journey.

  Swigert remained in the dying command vessel while the others powered up the LM. One by one he shut down Odyssey’s systems. He continued working by flashlight when darkness enveloped the cabin. Before he joined the others in the LM, he transferred the precise alignment of the ship’s guidance platform to a similar guidance system within Aquarius.

  As Swigert worked in the ship that Lovell now judged to be “forlorn and pitiful,” Lovell and Haise took apart Haise’s moonwalk pressure suit to rig up a ten-foot hose from the LM oxygen system. Running the hose into the command module enabled Swigert to remain there long enough to completely power down the ship they would later need to return to earth.

  As cramped as the command module had seemed, it was spacious compared with the lunar module. If they were to be sustained by the LM, the astronauts would need to return to the cold, damp, hibernating Odyssey for food and bathroom facilities. It would be an extremely uncomfortable three days.

  Watching Lunney’s team calculating flight trajectories, Deke told the others that things weren’t as bad as they seemed, a conclusion that seemed mad under the circumstances. He pointed out had the explosion occurred while Lovell and Haise were on the moon, or if the blast had come after the astronauts left the moon, linked up with Odyssey and were on the way home, nothing could have saved the men. Aquarius would be gone, and their only hope for survival would have been the crippled and dying command module.

  “If this had to happen,” Deke observed, “it couldn’t have come at a better time in this flight. Because it happened when it did, we just may get these guys home.”

  Kranz’s team had worked a maneuver that would provide the best chance for the Apollo 13 crew to make it back alive. “We’ll go for a brief burn a few hours from now before they reach the moon. That will give them the free-return trajectory. Then, we’ll do a second burn later to drop them into the slot for reentry. That brings them home in four days. So our job after the first burn is to figure out how we keep them alive before they run out of everything.”

  Five hours and thirty-five minutes after the crippling blast, the astronauts fired off the Aquarius descent engine for a thirty one second burn. Timing and engine thrust, along with alignment, were perfect. A critical milestone was behind them. “Okay, Houston. Burn’s complete,” Lovell confirmed. “Now we have to talk about powering down.”

  They had more than enough oxygen for the long trip home, but electrical power still hovered at critical levels. Without electricity to operate the fans that kept cabin air moving, the cabin would soon become fouled with the astronauts’ own exhalations. You don’t last long breathing carbon dioxide and water vapor.

  Under normal circumstances, lithium hydroxide canisters scrubbed carbon dioxide from the cabin. But the useful working time of the canisters aboard Aquarius was computed on the basis of what was required for sustaining two men for some forty hours on the moon. But now there would be three men, and the hydrogen peroxide would be consumed one-third more quickly. The canisters needed to sustain breathable air for three men for four days—or Lovell, Haise, and Swigert would choke on what Jim Lovell called the “exhaust of our own lungs.”

  There were more than enough lithium hydroxide purifiers in the command module, but they were square-shaped and would not fit the round openings on the LM’s system. Mission Control turned to Deke Slayton, the original “fix-it” man from combat and test pilot days.

  Thirty-six hours after the astronauts retreated to their lifeboat, a lunar cabin light flashed a warning that carbon dioxide was nearing dangerous levels. Loss of consciousness and death would follow quickly.
Slayton led a group of engineers who came up with what they called the “Wisconsin dairy-farm fix.” Using pressure-suit hoses, batteries, tape, plastic, and cardboard from a flight manual as a jerry-rigged scrubber, they managed to hook an Apollo purifier to the lunar module system.

  Mission Control led Swigert through a step-by-step assembly of the improvised device, which sucked carbon dioxide from the cabin, ran it through the makeshift scrubber, and returned fresh oxygen from the waste gases back to the cabin for the astronauts to breathe. Lovell, working with Swigert, said it was like building a model airplane.

  At forty-two years old, Lovell had three previous space flights under his belt. He had orbited the moon in Apollo 8 and had logged 572 hours in space-flight time before Apollo 13. Fred Haise, thirty-six, a rookie with exceptional qualifications, had played a key role in developing the lunar module. A leading expert on its systems, he had experience with the LM that would ultimately pay life-saving dividends. Jack Swigert, thirty-eight years old, who had not originally been scheduled for this flight, matched his experience in space. The command module pilot who had trained with Lovell and Haise for two years for this flight, Ken Mattingly, had been exposed to German measles shortly before scheduled liftoff. He had no immunity to the disease, and the NASA front office yanked him from the flight. Lovell accepted his backup, Swigert, who with only two days of training proved extraordinarily skilled in his duties.

  Apollo 13 swept around the moon to disappear behind its battered and cratered surface. Lovell, concentrating on the maneuvers that awaited the crew on the return trajectory was startled to see Haise and Swigert snapping photographs of the lunar surface as fast as they could adjust the apertures and speeds on their cameras.

  Lovell shook his head in disbelief. “If we don’t make this next maneuver correctly, you might never get those photographs developed.” They responded by pointing out that Lovell had been here before, they hadn’t, and they figured this was the only chance they’d ever get to shoot such pictures.