Apollo 13’s problem – 11–17 April 1970 2 страница

“It’s slowly going to zero,” Lousma responded. “We’re starting to think about the LEM lifeboat.”

Swigert, Lovell, and Haise exchanged nods. “Yes,” the command module pilot said, “that’s what we’re thinking about too.”

With an OK to abandon ship at last granted by the ground, the crew wasted little time in getting started. Assuming the men were entertaining any hopes of getting home, they could not just take up residence in the LEM and let their fading mother ship sputter to a halt like a car out of gas on a country road. Rather, since Odyssey would have to be used at the end of the flight for re‑entry, the ship would have to be shut off one switch or system at a time so as to preserve the operation of all of its instruments and maintain the calibration of their settings. Under ideal conditions, all three men would handle the job; under current conditions, however, Swigert would have to take care of things on his own, because at the same time Odyssey was being taken off line, Aquarius would have to be brought on line, a two‑man task that would have to be completed before the command module expired.

Lovell and Haise swam through the lower equipment bay and into the LEM, where they had broadcast their happy travelogue barely two hours earlier. Haise settled into his spot on the right side of the craft and surveyed the blacked out instrument panel. Lovell floated to his station on the left.

Swigert remained in Odyssey, still shutting down its systems, while Lovell and Haise were working in the LEM configuring the systems of the twin spacecraft. Odyssey’s controls had to be powered down before the LEM’s could be powered up. Swigert then joined Lovel and Haise in the LEM.

At Houston the shift changed. Glynn Lunney’s “Black” team took over from Kranz’s “White” team which began working on Apollo 13’s problems: how to bring them back before their resources ran out.

A spacecraft heading for the moon from Earth could take a “free return” trajectory which would take it around the moon and bring it back like a slingshot. But Apollo 13’s current flight path had been altered to allow it to go into lunar orbit so it would need to fire its engines to get onto the free return trajectory. An additional “burn” at PC + 2 would shorten its journey home. PC meant Pericynthion, the closest point to the far side of the moon; PC + 2 was two hours after this point. Lovell:

Of all of the problems Lunney faced, the most complex was the burn. In the hour or so since the astronauts had moved over to Aquarius, no definite decisions had yet been made about how to propel the docked ships toward home, and with the spacecraft moving closer to the moon, at a speed climbing back up to 5,000 miles per hour, the options were quickly fading. A direct abort, if one could even be attempted, got harder and harder the farther the ships got from Earth. A PC + 2 burn, if one was going to be attempted, would take a lot of planning, and the time for pericynthion was closing in fast. It would always be possible to fire the engine after the PC + 2 point, but the earlier in the earthward transit a burn was attempted, the less fuel it would take to affect the trajectory; the longer the burn was delayed, the longer the engine would have to be fired.

Chris Kraft was the former flight director. The control team had been expanded to four teams working in shifts, each team with its own flight director. Kraft was then deputy director of the Space Center. He had just returned to Mission Control from a press conference.

Pacing behind Kranz, who was also pacing, Kraft knew which return route he’d choose. The service propulsion engine, he was certain, was useless. Even if there was some way of mustering enough electricity to get the engine going, Kraft was not convinced that the crippled Odyssey would be able to take the strain. No one knew the condition of the service module, but if the force of the bang had been any indication, it was possible that the sudden application of 22,500 pounds of thrust would collapse the entire back end of the spacecraft, causing both docked ships to tumble ass over tea kettle, sending the crew not back toward Earth but barrel‑rolling down to the surface of the moon.

The only way home, Kraft figured, was to use the LEM’s engine – and more important, to use it right away. It would be tomorrow evening before the docked ships first passed behind the shadow of the moon, and it would be close to three hours beyond that before they reached the PC + 2 milestone. Waiting the better part of a day to get the crew on its homeward trajectory seemed nonchalant at best and downright reckless at worst. What Kraft wanted to do was fire the descent engine now, get the ship back on its free‑return slingshot course, and when it emerged from behind the moon and reached the PC + 2 point, execute any maneuvers that might be required to refine the trajectory or increase its speed.

In the past, when Chris Kraft had an idea like this, that idea got implemented. Nowadays, though, things were different. It was Gene Kranz who dictated the direction of things, Gene Kranz who was the true capo di tutti capi of the control room. If Chris Kraft wanted something done, he was free to suggest it to Kranz, but he could no longer decree it. In the aisle behind the flight director’s console, Kraft was about to stop Kranz’s pacing and discuss his two‑step burn idea when Kranz turned to him.

“Chris,” he said, “I sure as hell don’t trust that service module engine.”

“I don’t either, Gene,” said Kraft.

“I’m not sure we could fire it even if we wanted to.”

“I’m not either.”

“No matter what else we do, I think we’re going to have to go around the moon.”

“Concur,” Kraft said. “When do you want to burn?”

“Well, I don’t want to wait till tomorrow evening,” Kranz said. “How about we try a quick burn for a free return now, get that squared away, and then figure out if we want to speed them up with a PC + 2 tomorrow.”

Kraft nodded. “Gene,” he said after a considerable pause, “I think that’s a good idea.”

Two rows down and one console over, Chuck Deiterich, an off‑duty retrofire officer, or RETRO standing behind his accustomed console, and Jerry Bostick, an off‑duty flight dynamics officer, or FIDO, could not hear Kranz and Kraft’s discussion, but they knew the options as well as their bosses. Though it was Kraft and Kranz and Lunney who would ultimately decide the ship’s route home, it was Deiterich and Bostick and the other flight dynamics specialists who would have to come up with the protocols to pull the plan off. At the FIDO station, Bostick pushed his microphone out of range of his mouth, and leaned toward Deiterich.

“Chuck,” he said quietly, “How do we all want to do this thing?”

“Jerry,” Deiterich answered, “I don’t know.”

“I assume we’re ruling out Odyssey’s engine.”

“Absolutely.”

“I assume we’re going around the moon.”

“Absolutely.”

“And I assume we want to get them on free return as quick as possible.”

“Definitely.”

After a moment Bostick said, “Then I suggest we get our shit together fast.”

Close to a quarter of a million miles away, in the crowded cockpit of Aquarius, the men on whose behalf Bostick and Deiterich would be working had more elemental things on their minds than a return‑to‑Earth engine burn. Settling into his two‑man spacecraft with his three‑man crew, Jim Lovell had the chance to look around at the hand circumstance had dealt him. He did not like what he saw.

It was 58 degrees and falling inside the LEM but there was plenty of food because they had enough for a 10‑day trip. Lovell:

Lovell tried a pitch‑changing maneuvre from the LEM but the centre of gravity of the combined spacecraft made such maneuvres very awkward.

Capcom told Aquarius what they had decided. Lovell:

“Also Aquarius,” the Capcom now said, “we’d like to brief you on what our burn plan is. We’re going to make a free‑return maneuver of 16feet per second at 61 hours. Then we’re going to power down to conserve consumables, and at 79 hours we’ll make a PC + 2 burn to kick what we’ve got. We want to get you on the free‑return course and powered down as soon as possible, so how do you feel about making a 164 foot‑per‑second burn in 37 minutes?”

Lovell released the controller, allowed his ships to drift, and turned to his crewmates with a questioning look. Swigert, still at sea in the alien LEM, once again shrugged. Haise, who knew the LEM better than any man on board, responded similarly. Lovell turned his palms upward.

“It’s not like we have any better ideas up here,” he said.

“Do you think 37 minutes is enough?” Haise asked.

“Actually, no,” Lovell answered. “Jack,” he now said back to the Capcom, “we’ll give it a try if that’s all we’ve got, but could you give us a little more time?”

“OK, Jim, we can figure out a maneuver for any time you want. You give us the time, we’ll shoot for it.”

“Then let’s shoot for an hour if we can.”

“OK how about 61 hours and 30 minutes?”

“Roger,” Lovell said. “But let’s talk back and forth till then and make sure we get this burn off right.”

“Roger,” Lousma said.

The hour until the free‑return burn would be a frantic one for the crew. In a nominal mission, the flight plan allowed at least two hours for the so‑called descent activation procedure, the ritual of configuring switches and setting circuit breakers that preceded any burn of the LEM’s lower‑stage engine. The crew would now have barely half that time to do the same job, and do it without sacrificing the necessary precision. On top of that, there was still the elusive fine alignment to establish, something that, with all the space‑craft’s wild movements, Lovell was not yet close to accomplishing. But while the hour would be a breathless one aboard the ship, on the ground it would provide a chance to draw a breath.

Kranz’s team was working on how to make the consumable resources last long enough to bring them home. Lovell:

“For the rest of this mission,” Kranz began, “I’m pulling you men off console. The people out in that room will be running the flight from moment to moment, but it’s the people in this room who will be coming up with the protocols they’re going to be executing. From now on, what I want from every one of you is simple – options, and plenty of them.”

“TELMU,” Kranz said, turning to Bob Heselmeyer, “I want projections from you. How long can you keep the systems in the LEM running at full power? At partial power? Where do we stand on water? What about battery power? What about oxygen? EECOM” – he turned to Aaron – “in three or four days we’re going to have to use the command module again. I want to know how we can get that bird powered up and running from a cold Stop to splash – including its guidance platform, thrusters, and life‑support system – and do it all on just the power we’ve got left in the reentry batteries.”

“RETRO, FIDO, GUIDO, CONTROL, GNC,” he said, looking around the room, “I want options on PC + 2 burns and mid‑course corrections from now to entry. How much can PC + 2 speed us up? What ocean does it put us in? Can we burn after PC + 2 if we need to? I also want to know how we plan to align this ship if we can’t use a star alignment. Can we use sun checks? Can we use moon checks? What about Earth checks?

“Lastly, for everybody in this room: I want someone in the computer rooms pulling more strip charts from the time of translunar injection on. Let’s try to see if we can’t figure out just what went wrong with this spacecraft in the first place. For the next few days we’re going to be coming up with techniques and maneuvers we’ve never tried before. I want to make sure we know what we’re doing.”

Kranz stopped and glanced once more from controller to controller, waiting to see if there were any questions. As was often the case when Gene Kranz spoke, there weren’t any. After a few seconds he turned around and walked wordlessly out the door, heading back toward Mission Control, where dozens of other controllers were monitoring his trio of imperilled astronauts. In the room he left behind were the fifteen men he expected to save their lives.

Lovell gradually learnt how to control the attitude of the twin craft, the burn to correct trajectory for free return being so successful that no additional trim was required. Communication with Apollo 13 was subject to interference from its own third stage which was still following in the same trajectory.

After the free return burn Houston revised the astronauts’ work‑rest schedule. One astronaut slept in Odyssey while the other two kept kept six‑hour watches with an hour turn around. The hatch between was left open to allow enough air for a sleeping man but it was too cold and too noisy to sleep in Odyssey – Haise gave up after two hours and came back. They were all back on duty by 5 pm which was in time to prepare for the PC + 2 burn at 8.40.

Meanwhile there was a team change at Houston as Gerald Griffin’s Gold Team took over with Joe Kerwin as the new Capcom. The LEM’s descent engine was the main source of motive power available with its ascent engine only to be used if the descent stage was jettisoned. The descent stage contained most of the lander’s batteries and oxygen tanks. They had three possible burns: a superfast, medium or slow burn. A superfast burn had several disadvantages: it used up almost all the LEM’s fuel; they would have to jettison the service module as soon as possible; and they would land in the Atlantic where the US Navy had no recovery vessels. The medium burn was only a little slower than the superfast burn, its main benefit being that it retained the service module which protected the heat shield from the cold of space. They decided to take the slowest option.

Kraft and his flight directors let the arguments play out and watched, satisfied, as the men in the room settled for the slowest alternative. It was the choice the flight directors themselves had preferred, and it was the one the administrators would prefer. Now, as the arguments began to get into a consensus, Chris Kraft transformed the consensus into a decision.

“So it’s agreed,” he summed up. “At 79 hours and 27 minutes there will be an 850‑foot‑per‑second burn for four and a half minutes, aiming for a Paciflc splash at 142 hours. If all goes well, Apollo 13 will be home by Friday afternoon.”

Bill Peters was TELMU in charge of the LEM’s consumable resources. He had worked out how many systems needed to be shut down to provide enough water and power to get them home. Water was needed as a coolant. Hundreds of systems were taken offline, making the LEM even more uncomfortable. There was one outstanding problem: how to keep the LEM’s oxygen clean. Odyssey needed some of the LEM’s power to bring its batteries back up to the required level.

The PC + 2 burn required precise alignment. Checking by star sightings was impossible because of the glare from sunlight reflecting off the debris. The controllers concluded that they would have to use the sun itself to check their alignment.

In the front row of Mission Control, Russell, Reed and Deiterich listened to the crew and said nothing. At the Capcom station, Brand held his tongue until he was called again. At the flight director’s station Griffin pulled his log toward him and scribbled the words “Sun check initiated.” On the air‑to‑ground loop, the fractured chatter continue to flow back from the crew.

“Yaw right side,” Haise could be heard saying. “Commander’s FDI.”

“Deadband option,” Lovell responded.

“Plus 190,” Haise said. “Plus 08526.”

“Give me 16–”

“I’ve got HP on the FDI–”

“Two diameters out, no more than that–”

“Zero, zero, zero–”

“Give me the AOT, give me the AOT–”

For close to eight minutes, the murmuring of the crew continued as Aquarius swung its bulk around and the controllers eavesdropped in silence. Then, from off the right side of the ship, Swigert thought he saw something: a small flash then nothing, then a flash again. All at once, unmistakably, a tiny degree of the solar arc flowed into the corner of the window. He snapped his head to the right, then turned to the left to alert Lovell, but before he could say anything, a shard of a sunbeam fell across the instrument panel and the commander, monitoring his needles, looked up with a start.

“Call it, Jack!” he said. “What do you see?”

“We’ve got a sun,” Swigert said.

“We’ve got a big one,” Lovell responded with a smile.

“You see anything, Freddo?”

“No,” Haise said, squinting into his telescope. Then, as his eyepiece filled with light, “Yes, maybe a third of a diameter.”

“It’s coming in,” Lovell said, glancing out the window and turning away as the sun filled it. “I think it’s coming in.”

“Just about there,” said Haise.

“We’ve got it,” Lovell called. “I think we’ve got it.”

“OK,” Haise said, watching as the disk of the sun brushed the cross hairs of the telescope and slid downward. “Just about there.”

“Do you have it?” Lovell asked.

“Just about there,” Haise repeated.

In the telescope, the sun slid down another fraction of a degree, then a fraction of a fraction. The thrusters puffed hypergolics for another second or so, and then, silently, they cut off as the ship – and the sun – came to a stop. Lovell said, “What have you got? What have you got?”

Haise said nothing, then slowly pulled away from the telescope and turned to his crewmates with a huge grin.

“Upper right corner of the sun,” he announced.

“We’ve got it!” Lovell shouted, pumping a fist in the air.

“We’re hot!” Haise said.

“Houston, Aquarius,” Lovell called.

“Go ahead, Aquarius,” Brand answered.

“OK,” said Lovell, “It looks like the sun check passes.”

“We understand,” Brand said. “We’re kind of glad to hear that.”

In Mission Control, where only moments before, Gerald Griffin had called for absolute quiet, a whoop went up from the RETRO, FIDO, and GUIDO in the first row. It was taken up by the INCO and the TELMU and the Surgeon in the second row. Across the room, an undisciplined, unprecedented utterly un‑NASA‑like ovation slowly spread.

“Houston, Aquarius,” Lovell called through the noise. “Did you copy that?”

“Copy,” Brand said through his own broad grin.

“It’s not quite centered,” the commander reported. “It’s a little bit less than a radius to one side.”

“It sounds good, it sounds good.”

Brand glanced over his shoulder and smiled at Griffin who grinned back and let the tumult go on around him. Disorder was not a good thing in Mission Control, but for a few more seconds, at least, Griffin would allow it. He pulled his flight log toward him, and in the blank space under the Ground Elapsed Time column he wrote, “73:47.” In the space under the Comments column, he scribbled, “Sun check complete.” Looking down, the flight director discovered for the first time that his hands were shaking. Looking at the page, he discovered for the first time, too, that his last three entries were completely illegible.

As the LEM moved onto the dark side of the moon, the crew were able to use the position of the stars to check their alignment for the PC + 2 burn. They were out of radio contact for 25 minutes – when they regained contact they had accelerated because of the moon’s gravity. Vance Brand was Capcom at the time of the PC + 2 burn. He called 2 minutes 40 seconds to burn.

There was a long silence.

“One minute,” Brand announced.

“Roger,” Lovell answered. Sixty more seconds of silence.

“We’re burning 40 percent,” the radio officer now heard Lovell call.

“Houston copies.” Fifteen seconds passed.

“One hundred percent,” Lovell said.

“Roger.” Static roared in the background. “Aquarius, Houston. You’re looking good.”

“Roger,” Lovell crackled back. Another sixty seconds passed.

“Aquarius, you’re still looking good at two minutes.”

“Roger,” Lovell said. More static, more silence.

“Aquarius, you’re go at three minutes.”

“Roger.”

“Aquarius, ten seconds to go.”

“Roger,” Lovell said.

“Seven, six, five, four, three, two, one,” Brand ticked off.

“Shutdown!” Lovell called.

“Roger. Shutdown. Good burn, Aquarius.”

“Say again,” Jim lovell shouted hack through the radio hiss.

Brand raised his voice. “I – say – that – was – a – good – burn.”

“Roger,” Lovell said. “And now we want to power down as soon as possible.”

Splash down would be 600 miles east of US Samoa, on Friday. Meanwhile Houston decided the crew had to execute Passive Thermal Control and then power down and get some sleep. They were still 225,000 miles from home.

Ed Smythe was chief of the crew systems division. He had to solve the problem of cleaning the air of carbon dioxide, which was done by lithium hydroxide cartridges. Unfortunately the cartridges of the two modules were not interchangeable – the LEM’s cartridges were round but the command module’s were square. The LEM’s remaining cartridge would expire when the duration of the mission reached 85 hours.

For the next hour, the work aboard Apollo 13 had little more orderliness than a scavenger hunt, and little more technical elegance. With Kerwin reading from the list of supplies Smylie had provided him, and Kraft, Slayton, Lousma, and other controllers standing behind him and consulting similar lists, the crew were dispatched around the spacecraft to gather materials that had never been intended for the uses to which they were about to be put.

Swigert swam back up into Odyssey and collected a pair of scissors, two of the command module’s oversized lithium hydroxide canisters, and a roll of gray duct tape that was supposed to be used for securing bags of refuse to the ship’s bulkhead in the final days of the mission. Haise dug out his book of LEM procedures and turned to the heavy cardboard pages that carried instructions for lifting off from the moon‑pages he now had no use for at all – and removed them from their rings. Lovell opened the storage cabinet at the back of the LEM and pulled out the plastic‑wrapped thermal undergarments he and Haise would have worn beneath their pressure suits while walking on the moon. No ordinary long johns, these one‑piece suits had dozens of feet of slender tubing woven into their fabric, through which water would have circulated to keep the astronauts cool as they worked in the glare of the lunar day. Lovell cut open the plastic packaging, tossed the now useless union suits back into the cabinet, and kept the now priceless plastic with him.

When the materials had been gathered, Kerwin began reading up the assembly instructions Smylie had written. The work was at best slow going.

“Turn the canister so that you’re looking at its vented end,” Kerwin said.

“The vented end?” Swigert asked.

“The end with the strap. We’ll call that the top, and the other end the bottom.”

“How much tape do we want to use here?” Lovell asked.

Kerwin said, “About three feet.”

“Three feet…” Lovell contemplated out loud.

“Make it an arm’s length.”

“You want that tape to go on sticky end down?” Lovell asked.

“Yes, I forgot to say that,” Kerwin said. “Sticky end down.”

“I slip the bag along the canister so that it’s oriented along the sides of the vent arch?” Swigert asked.

“Depends what you mean by ‘sides’,” Kerwin responded.

“Good point,” Swigert said. “The open ends.”

“Roger,” Kerwin responded.

This back‑and‑forth went on for an hour, until finally the first canister was done. The crewmen, whose hopes for technical accomplishment this week involved nothing less ambitious than a soft touchdown in the Mauro foothills of the moon, stood back, folded their arms, and looked happily at the preposterous tape‑and‑paper object hanging from the pressure‑suit hose.

“OK,” Swigert announced to the ground, more proudly than he intended, “our do‑it‑yourself lithium hydroxide canister is complete.”

“Roger,” Kerwin answered. “See if air is flowing through it.”

With Lovell and Haise standing over him, Swigert pressed his ear against the open end of the canister. Softly, but unmistakably, he could hear air being drawn through the vent slats and, presumably, across the pristine lithium hydroxide crystals. In Houston, controllers crowded around the sreen at the TELMU’s console, staring at the carbon dioxide readout. In the spacecraft, Swigert, Lovell, and Haise turned to their instrument panel and did the same. Slowly, all but imperceptibly at first, the needle on the CO₂ scale began to fall, first to 12, then to 11.5, then to 11 and below. The men on the ground in Mission Control turned to one another and smiled. The men in the cockpit of Aquarius did the same.

“I think,” Haise said to Lovell, “I might just finish that roast beef now.”

“I think,” the commander responded, “I might just join you.”

The next problem was that their angle of trajectory was becoming too shallow for re‑entry – something was eroding it. Houston considered a small burn to correct the angle. The latest consumables report was favourable: electricity consumption was actually below their projections. Their speed was accelerating as the earth’s gravitational pull increased and that of the moon decreased.

Haise was on watch when:

Just as Haise approached the right‑hand window, a chillingly familiar bang‑whump‑shudder shook the ship. He shot his hand out, braced himself against the bulkhead, and froze in mid‑float. The sound was essentially the same as Monday night’s bang, though it was unquestionably quieter; the sensation was essentially the same as Monday night’s shudder, though it was unquestionably less violent. The locus of the event, however, was utterly different. Unless Haise was mistaken – and he knew he wasn’t – this disturbance had not come from the service module, at the other end of the Aquarius‑Odyssey stack, but from the LEM descent stage below his feet.

Haise swallowed hard. This should be the helium burst disk blowing: if the ground has told you to expect a venting and a moment later your ship bangs and rocks, chances are the two are connected. But viscerally, Haise – the man who understood Aquarius better than anyone else on board – knew this wasn’t true. Burst disks didn’t sound this way, they didn’t feel this way, and, floating cautiously up to his porthole and peering out, he also saw that they didn’t look this way. Just as Jim Lovell had discovered vented gas streaming past his window more than forty hours ago, Haise, the LEM pilot, was alarmed to see much the same thing outside his window now. Drifting up from Aquarius’s descent stage was a thick white cloud of icy snowflakes, looking nothing at all like misty helium streaming from a burst disk.

“OK Vance,” Haise said as levelly as he could, “I heard a little thump, sounded like down in the descent stage and I saw a new shower of snowflakes come up that looked like they were emitted from down that way. I wonder,” he said somewhat hopefully, “what the supercritical helium pressure looks like now.”

Brand froze in his seat “OK,” he said. “Understand you got a thump and a few snowflakes. We’ll take a look at it down here.”

The effect of this exchange on the men in Mission Control was electric.

“You copy that call?” Dick Thorson, at the CONTROL console, asked Glenn Watkins, his backroom propulsion officer.

“Copied it.”

“How’s that supercrit look?”

“No change, Dick,” Watkins said.

“None?”

“None. It’s still climbing. That wasn’t it.”

“CONTROL, Flight,” Gerry Griffin called from the flight director’s station.

“Go, Flight,” Thorson answered.

“Got an explanation for that bang?”

“Negative, Flight.”

“Flight, Capcom,” Brand called.

“Go, Capcom,” Griffin answered.

“Anyone know what that bang was about?”

“Not yet,” Griffin said.

“Anything at all we can tell him, then?” Brand asked.

“Just tell him it wasn’t his helium.”

As Brand clicked back on to the air‑to‑ground loop and Griffin began polling his controllers on the flight director’s loop, Bob Heselmeyer at the TELMU station began scanning his console. Looking past the oxygen readouts, past the lithium hydroxide readouts, past the CO₂ and H₂O readouts, he noticed the battery readouts, the four precious power sources in Aquarius’s descent stage that, working together, were barely providing enough energy for the exhausted, overtaxed ship. Gradually, the readout for battery two – just like the too easily recalled readout for Odyssey’s O₂ tank two – had slipped below what it should be and was failing steadily.