We still didn’t know why it had happened, but mission control worked out that an oxygen tank must have exploded in the service module, damaging vital equipment. They quickly canceled the moon landing and pressed the lunar module into service as a lifeboat. The command module had lost its primary source of power in the explosion, and yet it was the spacecraft with a heat shield and parachutes. So the crew had to hang on as long as possible in the lunar module while they rounded the far side of the moon and swung back toward Earth. Then they would need to power up the command module just long enough to attempt reentry. So many things had to go right for the plan to work that I didn’t know if Jack, Fred, and Jim would make it. Both spacecraft would be pushed far beyond their design specifications.
Using the spacecraft simulators in Houston, we hoped to give the crew as much help as possible. We simulated and tested huge numbers of possible survival procedures. This had to be done fast, so we split the jobs between astronauts. I helped Ken Mattingly, Joe Engle, and Stu Roosa while they simulated the flight in both the lunar module and command module. Mission control hurriedly wrote procedures and raced them over to us. We’d test them, make changes, and run them back, over and over, until they were as good as we could make them in the small window of time the crew had left.
The trickiest simulation work was in the lunar module, the spacecraft the crew relied on the most. Designed to land two astronauts on the moon, the lunar module now needed to keep three people alive for a journey around the moon and back. Its engine also had to keep them on course. To fly a straight thrusting maneuver, one astronaut would have to think in terms of up-and-down motion, while the other needed to think sideways, just to keep from veering off course. The thrusting maneuvers had to be done manually, because the lunar module’s computer was not designed to calculate maneuvers with the extra mass of an attached command module. It was tough to simulate, completely backward to our prior training, and for three cold, tired, and hungry colleagues in space it was even tougher.
When I first heard the TV announcement in my apartment, I thought the crew had no chance; Jack, Fred, and Jim were going to die. But when we started testing the procedures I began to see that although it was a long shot, we might get the crew back. It still felt like a long shot until they swung around the moon and started home. It was then a question of whether the crew could survive long enough in the lunar module.
Without any power, the LM became painfully cold. Fred Haise felt increasingly sick as the days went by, and we were powerless to help. The three guys just had to endure. But we could help them find a way to keep the air-purification system working. The lunar module was not designed to keep three people alive for so long, and the canisters designed to purify the air in the command module were the wrong shape. Astronauts, mission controllers, and equipment specialists huddled together and quickly devised a way to jury-rig a system using materials we knew were on board: cardboard, plastic bags, hoses from spacesuits, and lots of duct tape. This hastily invented contraption allowed the command module’s square canisters to work in the lunar module that used round canisters.
As the flight progressed, I became increasingly impressed by Fred Haise. A great pilot and a very smart guy, his lunar module knowledge was vital to their survival. Now we had to hope the explosion had not damaged the command module’s electrical system. Once the crew floated back into that spacecraft and undocked from the lunar module, they only had a small amount of battery power for reentry. The crew could not use those batteries until the last moment. The team in Houston wrote an improvised timeline so the crew could quickly power up a cold, dead spaceship using only that tiny power supply. It all had to happen very quickly at the end of the mission.
Six brutal days after liftoff the crew made it safely back to earth, with a splashdown watched around the world almost as intensely as the Apollo 11 moon landing. Once I saw those main chutes fully deployed and knew that the crew was safe, I could join the cheers and celebrations.
We’d just had a major spacecraft failure that nearly cost us a crew. My own flight was only two missions away. It was evident that Apollo 15 wasn’t going to the moon any time soon—at least until we worked out what had caused the spacecraft explosion and fixed the problem. I didn’t have time to dwell on it. As far as our crew was concerned, our moon mission was on. We’d have to wait longer while the service module was modified, but we could use that time to train even harder. And boy, did we have some tough training ahead of us.
However, the Apollo 13 emergency wasn’t the only event in the spring of 1970 that threatened to delay our flight. A routine NASA physical revealed that I had a small abdominal hernia, and the doctors recommended surgery. Any medical condition when you are on a flight crew always results in a few sleepless nights.
NASA quickly set up an appointment for me at a hospital in downtown Houston. I stayed there for two days, trying to figure out how long it would take to get back to playing handball, my favorite sport. The day after the operation, a nurse showed up in my room with a wheelchair, asking if I’d like to tour the hospital. If anyone would be wheeled around, I replied, it would be her. She called my surgeon for support, but he told her to let me do whatever I wanted. So I gleefully pushed the nurse around the hospital. My recovery did not take long, and soon I was back playing handball. To my immense relief, the successful surgery did not affect my flight standing at all.
As we trained, and I came to know my crewmates even more, I discovered something I didn’t previously know about Jim Irwin. He was happily married—to his second wife. But Deke didn’t care about Jim’s fleeting first marriage, which had ended long before he came to NASA, and why should he? It created no drama, no publicity, and no impact on his work. If Jim’s divorce had made it into the papers and tarnished NASA’s reputation, Deke would have acted differently. Nevertheless, I was amused that for all of NASA’s worries about public perception, it managed to fly two divorced astronauts on Apollo 15. And that fact never made the press. But then, Jim and I weren’t playboys.
As a prime crew, we were allowed a lot more time in simulators than we’d ever been able to scrape together as a backup crew. It felt like I spent half my life in an Apollo simulator in those years. I probably worked in them for about fifteen hundred hours over a two-year period. The outside world, its problems, and personalities, shrank away to nothing as we gave all of our efforts to months of intense training.
Our command module was in Downey, of course, so we spent a lot of time there. Soon, one day melted into another. We’d work all day, then go over to the athletic club in nearby Long Beach and play handball with guys who were at least twenty years older. They beat the hell out of us, but at least we would get a good workout. We would have a beer, go back to the hotel, sleep, get up, and do it all over again. The schedule was not glamorous stuff; in fact, it could be extremely tedious.
I’d love to tell you that preparing to fly to the moon was always exciting and interesting. Frequently, however, it wasn’t. Much of our work was detailed testing, and we would work through the day minute by minute. In a test procedure, for example, we were told to flip a particular switch, and then wait ten minutes for the engineers to analyze what happened when it came on. Then we’d be asked to turn it off, flip another switch, and wait again. With hundreds of switches and circuit breakers in the spacecraft and thousands of different switch combinations, this process took a very long time.