Two hundred thousand miles from home, the crew of Apollo 13 are falling from an enormous distance back towards Earth, travelling faster and faster, thousands and then tens of thousands miles per hour as they get closer. But to enter the atmosphere safely, they’ll need precision as well as speed. Ever since the long PC+2 burn they did after swinging around the Moon, retro flight controller Chuck Dietrich has been closely tracking the spacecraft’s trajectory and he’s noticed they’re off course (Chuck Dietrich) After PC+2, we were gonna actually miss the Earth and we had a resulting perigee of 87 miles (Kevin Fong) And a perigee …? (Chuck Dietrich) A perigee is how far above the Earth you are. And we needed to be down, a perigee around 20 miles to even re-enter the atmosphere Off course by almost 70 miles, and entering at too shallow an angle, this trajectory will see the astronauts ricochet off the upper layers of the atmosphere and maroon them in space. They need to take action. They need to correct their course, but flying their powered-down spacecraft comes with a host of new challenges (Jim Lovell) Our guidance system was no longer on. How can we make a change if we don’t know where we are? How do we make a change to know where we’re supposed to go? From the BBC World Service, this is 13 Minutes to the Moon, season 2. I’m Kevin Fong and this is the incredible story of the flight of Apollo 13, told by the people who flew it and saved it (Mission audio) OK Houston, we’ve had a problem here. We got more than a problem We lost 02 tank 2 pressure. That can’t be Let’s make sure we don’t blow the whole mission. There’s one whole side of that thing missing. That’s the end right there Episode 6 Earth in view Lovell, Haise and Swigert are presented with a challenge that no other Apollo crew has ever faced. They are forced to do a critical course-correction burn without their Inertial Measurement Unit – the 3D compass needle that tells them which way the spacecraft is pointing. Remember, that’s been switched off so there’ll be enough power in the lunar module’s batteries to get them back to Earth The crew’s lives now depend not on their computer, but on their instincts as pilots and explorers – the dead reckoning of their eyeballs and the movements of their hands at the controls (Mission audio) During the burn, of course, you’ll be controlling pitch and roll. Understand Haise and Lovell begin to steer the spacecraft, pivoting it around, trying to point it in the right direction so that when they fire the lunar module’s engine, it will send them on the right course. And they are looking for a solid reference point (Mission audio) Go ahead, Aquarius. We’re manoeuvring around here to fish for the Earth They have lined up a crosshair on the lunar module’s windowpane with the shadow which crosses the whole of the Earth’s surface from north to south: the line between night and day – known as the Terminator. Even from hundreds of thousands of miles away this feature is distinct enough to guide them With the console switched off, the only thing they can use to time the burn accurately is Jim Lovell’s wristwatch. Swigert will be the time keeper, and the burn needs to last exactly 14 seconds – this isn’t like the much longer PC+2 burn where they were trying to speed up. This is all about getting back on the right course (Jim Lovell) We were all busy. Everybody had their own particular job to do because getting the spacecraft and the proper position manually was rather difficult For the astronauts, this is old-fashioned flying, very nearly by the seat of their pants Lovell pitches the spacecraft up and positions the crosshair on the Terminator Haise controls the roll, manoeuvring it round until he catches a glimpse of the Sun though
the lunar module’s alignment optical telescope With these two reference points fixed – the Earth and the Sun – they’re almost ready (Mission audio) Okay, Houston. We have our attitude set. Roger, Jim, I hope the guys in the back room who thought this up right knew what they were saying Amazingly Jim Lovell had actually rehearsed this manoeuvre while training for Apollo 8 – but back then he never imagined he’d have to do it for real (Mission audio) OK, Aquarius. The attitude looks good here and your choice when you want to start the burn For 14 seconds, one of the first men to orbit the Moon briefly becomes a pioneer again, flying his spacecraft using celestial bodies for navigation, relying purely on his skills as a pilot (Mission audio) Mark it. One minute. Roger Fred In a support room in mission control, Poppy Northcutt, an engineer who specialises in return-to-earth manoeuvres, sits waiting, knowing how essential it is to get the spacecraft’s course right (Poppy Northcutt) You can come in at the wrong angle and burn up. You can come in at the wrong angle and skip off the atmosphere and go deflected off into space. It’s extremely important that the burn be accurate No guidance computer. No autopilot. In the dark, Lovell has his hand on the red engine ignition button, the other on the lunar module’s pitch control. At his side, Haise will control yaw (Mission audio) Engine Arm to Descent Fourteen critical seconds. Jack Swigert floats just behind his crewmates. His eyes glued to the second hand of Jim Lovell’s wristwatch (Mission audio) Ignition (Jim Lovell) The spacecraft was very difficult to manoeuvre (Mission audio) Thrust looks good (Jim Lovell) I of course had my eyes peeled on the optics to make sure the crosshair stayed on the Earth’s Terminator (Mission audio) Shutdown. 470. OK, looks good, nice work. Let’s hope it was Neither the astronauts nor the flight controllers know if the burn has worked. In its low power state, the flow of data from the spacecraft has slowed to a mere trickle. It will be hours before they know for sure (Poppy Northcutt) Think about going to the pub and you’re shooting darts. And say you’re twenty feet away from the dartboard. If you have a little bit of error in your dart shooting, you’ll still hit the dartboard, right? You might not hit the bullseye in it but you’ll hit the dartboard if you’re just off a little bit in the angle of your throwing of the dart or a little off in how hard you’re throwing Now move that back so that you’re a mile away from the dartboard. A tiny error is going to miss the board entirely During the burn, Fred Haise was watching two yellow needles on the lunar module’s control panel, which gave a rough measure of how steadily they were holding their course. Decades later, in conversation with me, he recalled that manoeuvre with the characteristic understatement of an old and bold pilot (Fred Haise) You didn’t have to hold it very long. There was very little deviation in fact – it was easy to hold. The needle was pretty well centred (Kevin Fong) Your description of it is somewhat at odds with the Apollo 13 movie (Fred Haise) If you look at the mission report, we did not move even one degree in any axis (Kevin Fong) So it’s a bit of a work of fiction, the scene from the movie? (Fred Haise) Oh yeah well, that’s Hollywood Misson control analyses their data. The 14-second burn is good. Their course is not yet perfect but is close enough for the time being. And there are now more pressing matters. The physical stresses of the mission have suppressed Haise’s immune system. He is becoming unwell with an infection affecting his bladder and kidneys (Jim Lovell) We had our spacesuits off and it was still kind of cold, getting colder Fred was getting chilled and I wondered what the story was with him (Kevin Fong) Were you worried about him? (Jim Lovell) Yeah I was worried about Fred so I comforted him a little bit – put my arms around him and tried to get my body heat, get him some more heat into his body (Fred Haise) I had developed a urinary tract infection and had gone through chills and fever and that kind of thing. I felt fully competent and alert. A little adrenaline helped keep you alert in any case. But no, I was not bed-ridden by any means, even from that
particular affliction As you can tell, Fred Haise is nothing if not resilient. And here he’s downplaying the seriousness of his illness. We now know that spaceflight depresses the immune system, even before an astronaut is malnourished, cold and short of sleep. On Earth, a urinary tract infection severe enough to spread from the bladder to affect the kidneys is a cause for concern in anyone. And so for Haise, locked in his spacecraft, it would have been dangerous The lunar module Aquarius has been the astronauts’ home now for three days. Despite the lack of creature comforts it has kept them safe and more than done its job as a lifeboat But it can’t get them all the way home They still need the sturdy command module and its heat shield for re-entry. And so, with less than 24 hours left before they’re due to reach Earth, their attention must now turn to heading back into Odyssey – their dead command module – and trying, somehow to resurrect it. Flight director Gene Kranz has put John Aaron in charge of that task – he’s working with electrical systems specialist Jim Kelly (John Aaron) Normally when you power up the spacecraft, you go out to the pad and take two, three days to power up very systematically, you know, check everything on the data stream and all that. Sit there for three days in advance. That’s not the power up we could do (Jim Kelly) The Command Module was dead. We had three batteries only. There was no other power source For the past two days, Aaron and Kelly have been working on this exact problem. They’re trying to power up a spacecraft that was never designed to be shut down in space. And trying to do that in a way that gives you enough systems to navigate home and survive re-entry and splash-down, but without using so much power that your batteries run dead before the crew is safely home and dry John Aaron finally has a solution. Working with just enough battery power to keep a hair dryer running for a couple of hours, he has spread that across the systems in the command module as thinly as he dares He thinks it will work but his ideas now have to be turned into a set of explicit instructions that can be read up to the crew by CAPCOM This involves dozens upon dozens of switch throws that have to happen in exactly the right sequence. If they get it wrong, if they use too much power, they won’t survive To reiterate: if the battery dies, the crew dies. So they’re taking their time to get the procedures just right, but aboard Apollo 13 Jim Lovell is getting impatient (Jim Lovell) I kept looking at the Earth that it was getting a little bigger all the time And I thought to myself, we don’t have the procedures to get the command module guidance system working again, get it reactivated, and we had to make sure that all the environmental system was going back and everything like that… And so I called down. I said, Guys, we gotta hurry up, I see the Earth coming in closer. We need to know how to power up the command module. I was quite worried (Kevin Fong) Did it ever occur to you that the procedure list might never arrive on time? (Jim Lovell) Well, that gave me a thought that the procedure wouldn’t arrive but I would have been talking to them in all kinds of foul language if it hadn’t arrived. So, I guess they got the word that that was the one thing that they had to work on (Kevin Fong) I mean, they stall you a couple of times, don’t they? At one point, I think Joe Kerwin, in response to your question, says, you say is there a checklist? And he says it exists I asked Joe Kerwin about that (Kevin Fong) At one point he fairly grumpily asks, Where’s the checklist? And you reply, It exists (Joe Kerwin) Get a little philosophy there, huh?! I knew that Ken Mattingly and the guys were over in the simulator polishing that thing off, checking and rechecking it and making sure it was right. You know, nobody had ever powered up a command module from zero, especially not in orbit. This was not supposed to happen. It was cold. There was condensation in the command module. There’s a cold dirty swamp in there. And the object: you had three hours of battery power to get that thing up – switch by switch, sub system by sub system – until it was full powered, and still have time enough to jettison the
service module, get the stars and align the platform in the command module, then jettison the lunar module, and do all of that stuff, and get into attitude, and come home. It was a crowded menu. So I don’t mind, I don’t blame Jim being grumpy – he wanted to get in there and go over it one time, please, and anyway they were getting tired And mission control’s delaying tactics didn’t end there (Mission audio) We’re just having a ball down here working on all kinds of new procedures and we expect to have your entry procedures out here by Saturday or Sunday at the very latest. Saturday or Sunday? At the very latest! (Kevin Fong) And of course you were due to splash down on Friday (Jim Lovell) Yeah, just a little bit too late Jim and Joe can laugh about it now but at the time the pressure was very real, especially for John Aaron (John Aaron) We got this sequence really compressed and I wonder if the crew can do it. As soon as we got to that point, they can go test it in the simulator. It was my ideas and Jim Kelly’s ideas, and a couple of others. But it wasn’t my plan. By the time they got read up, it was everybody’s plan. It had been smoked over really close. And you know, we had thousands… The whole country was working on that plan With just 17 hours to go before re-entry, Lovell is still waiting impatiently for the procedure. John Aaron and Jim Kelly are hurrying down corridors, with a clutch of papers in their hands, having called ahead to tell mission control that the plan is finally ready (Mission audio) And we’re ready to read you the first checklist instalment. OK Jack. I’m going to get – Vance, I’m going to get Jack on the line for that and so stand by. OK And he’ll need a lot of paper (John Aaron) We walked in there with it – I’m think a flight crew support guy was with us We walked in there with it, and it was a stack of stuff, and laid it on the flight director’s, on the Capcom’s console and I said, OK, here it is. It’s ready. Read it up! And the first thing I heard in the room and I think it was from Kranz, Where’s my copy? And I said, This is it. He said, Time out Go run 25 copies of it. Copies in 1970 were not as easy to make as they are today (Mission audio) I’m on and ready to copy OK, Jack. Wait one. We want to get one into the hands of Flight and EECOM, and it’ll take about a minute or two. Sorry to wake you up for this, but take about a minute, and then we’ll read it up to you Lovell’s patience runs out (Mission audio) Houston, Aquarius. Go ahead, Aquarius. Vance, we’ve got to realise that we’ve got to establish a work-rest cycle up here, so we just can’t wait around here to just read procedures all the time up to the burn. We’ve got to get them up here, look at them, and then we’ve got to get the people to sleep. So take that into consideration when you get ready to send up the PADs. I know, Jim. We’re very conscious of that. We, we should be ready to go in about five minutes That’s all I can say. Stand by. OK Finally, John Aaron returns with 25 copies of the power-up procedures in hand (Mission audio) OK. Procedures coming back in again with multi copies for distribution Ken Mattingly, bumped from the flight, has been heavily involved in creating the checklist He’ll now read the vital procedure up to the crew (Mission audio) Hello, Aquarius; Houston How do you read? OK. Very good, Ken. OK, let me take it from the top here. And the first item, then, after you get ready to start this checklist, is to install lithium hydroxide canisters and to stow ORDEAL. On panel 8, we want to turn the Floodlights to Fixed OK. Wait a minute. You’re going too fast, here. OK. I’ll tell you. I’ll go a line at a time and wait for your verification before I go on to the next one. I have panel 8, Floodlights, Fixed. OK Install LiOH canisters, stow Ordeal, Floodlights, Fixed. OK. That’s the panel 8 floodlights. Now we’re going to take panel 5. There are some plumbing switches here Let’s take the Surge Tank Oxygen valve to On. Surge Tank
02 to On. All right. Take the Main Regs. And Relief valves to Both. That’s correct. And Emergency Cabin Pressure valve to Both… That’s affirmed. And let’s go back to page 1-6, line 41. Let’s put in a time – Minus 4, 40. Minus 4, 40 Floating in the cold, dark of the lunar module, Jack Swigert is listening to the man he replaced as command module pilot on the crew of Apollo 13. Mattingly dictates instructions and Swigert writes down exactly what he hears. Pencil in hand, Swigert scavenges scraps of paper from notepads and flight manuals. If he makes a mistake in copying the procedure down, it won’t work and they’ll never get home (Mission audio) OK it sounds good. OK. Now, let me give you some plumbing switches here Take the Main Regs, to Open (John Aaron) I still have nightmares about the fact that Jim Kelly and all of us put together this very complex, compressed sequence that there was no time to redo – read it up in its complexity, word by word, line by line. The thing I didn’t take into account when I built that sequence is the fact that the crew was in this austere environment Cold and damp. I mean, they couldn’t sleep You can’t sleep when it’s cold. This person may not be fully awake in 100 per cent cognitive skills when this was going on. It took two and a half hours just to read it up (Kevin Fong) Two and a half hours of just, just reading instructions up to the crew (John Aaron) Yeah, and the crew would say, OK, yeah, I got that. Then they might ask a little question here, and they’d be reading the next bit. It was switches and circuit breakers and comments. Two and a half hours (Mission audio) OK Jack. It looks like we’ve closed up the loose ends here. We think we’ve got all the little surprises ironed out for you. I hope so because tomorrow is examination time. Rog The Earth looms large in the windows of their spacecraft. Re-entry is now a little over 14 hours away. Tomorrow, Jack Swigert must put his copy of the power-up checklist into action, hoping that the guys on the ground have got it right, and that he can successfully resurrect the dead command module. But for now it’s time for the crew to get some rest, to prepare themselves for the challenges of what will be the last day of the mission of Apollo 13 (Mission audio) Just out of curiosity, did you all get a readout on what the cabin temp was up there? Yeah, we’re getting 45 to 46 degrees. Now do you see why we call it the refrigerator. Yes, it’s kind of a cold winter day up there, isn’t it? Is it snowing in the command module yet? No, no, not quite. The windows are in pretty bad shape. Every window in the command module is just covered with water droplets. It’s going to take a lot of scrubbing to get those cleared off. Roger Understand. You’ll have some time on the beach in Samoa to thaw out after this cold experience. Hey, that sounds great (Mission audio) Apollo control, Houston. Our countdown clock shows that we’re 19 minutes away now from time of separation, service module jettison. Before this Jack Swigert … It’s been more than three days since the explosion in the service module – the cylindrical section of the spacecraft, below the cone-shaped command module. No longer able to generate power or be used as a means of propulsion, it’s been a dead weight since the accident The crew have so far been unable to see any of the damage directly but they felt the lurch and heard the bang accompanying the explosion They have witnessed the havoc it wreaked with their systems, and have watched clouds of debris floating outside. They cut the service module free, and crowd around the command module windows to get their first glimpse of the damage. And they’re in for a shock (Mission audio) And there’s one whole side of that spacecraft missing. Is that right?
Right by the, right by the high gain antenna, the whole panel is blown out, almost from the base to the engine. Copy that. Yes, it looks like it got to the SPS bell, too, Houston It’s really a mess. Man, that’s unbelievable (Fred Haise) The damaged area – that whole quarter of the spacecraft where it had blown off – seemed much larger than we had experienced, thinking back. We wouldn’t have thought a quarter of a spacecraft had blown off The damage is much worse than anyone had imagined It has ripped off an entire side panel, damaging the bell-shaped nozzle of their main engine, right up to the point where the service module was joined to the command module. And crucially that section of torn and twisted metal is the part of the service module that has been sitting right next to the command module’s heat shield. As it continues to drift away, a new fear rises (Jim Lovell) I was quite worried, I didn’t know before, but with the whole panel was missing, how big was that explosion? Had that damaged the heatshield and blew some of parts of the heatshield away?. So we were really worried because as we went through the atmosphere, the temperature of the heatshield would come up around 3000 degrees Fahrenheit The heat shield is a honeycomb of fibreglass, stainless steel and resin, coating the command module. It’s designed to burn off in layers as the spacecraft re-enters the atmosphere, holding the inferno safely at bay and away from the astronauts. But any damage to that shield – even the slightest crack – would allow the fierce heat to creep in, destroying the capsule and incinerating its crew. This thought is heavy in their minds. But there is nothing they can do. The inferno of re-entry lies in wait, just four hours away 13 Minutes to the Moon is an original podcast from the BBC World Service This episode was written by me, Kevin Fong, and producer Chris Browning. In the trench with us was Series Editor Rami Tzabar. Our theme music is by Hans Zimmer and Christian Lundberg Technical production is by Tim Heffer, and our story editor is Catherine Winter of In the Dark at APM Reports We’d love it if you shared this podcast with your friends on social media – our hashtag is #13MinutestotheMoon and where you can, please do leave ratings and reviews in your podcast app. The World Service Podcast Editor is Jon Manel and the Senior Podcast Producer is Rachel Simpson. And thanks to our digital team