As Apollo 13 Sped Toward Earth

8/7/2019 As Apollo 13 Sped Toward Earth

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By STEPHEN CASS / APRIL 2005

13 April 2005--"Houston, we've had a problem."

Thirty-five years ago today, these words marked the start of a crisis that nearly killed three

astronauts in outer space. In the four days that followed, the world was transfixed as the

crew of Apollo 13--Jim Lovell, Fred Haise, and Jack Swigert--fought cold, fatigue, and

uncertainty to bring their crippled spacecraft home.

But the crew had an angel on their shoulders--in fact thousands of them--in the form of theflight controllers of NASA's mission control and supporting engineers scattered across the

United States.

To the outsider, it looked like a stream of engineering miracles was being pulled out of

some magician's hat as mission control identified, diagnosed, and worked around life-

threatening problem after life-threatening problem on the long road back to Earth.

From the navigation of a badly damaged spacecraft to impending carbon dioxide

poisoning, NASA's ground team worked around the clock to give the Apollo 13 astronauts

a fighting chance. But what was going on behind the doors of the Manned Spacecraft

Center in Houston--now Lyndon B. Johnson Space Center--wasn't a trick, or even a case

of engineers on an incredible lucky streak. It was the manifestation of years of training,

teamwork, discipline, and foresight that to this day serves as a perfect example of how to

do high-risk endeavors right.

Many people are familiar with Apollo 13, thanks to the 1995 Ron Howard movie of the

same name. But as Howard himself was quick to point out when the movie was released,

it is a dramatization, not a documentary, and many of the elements that mark the

difference between Hollywood and real life are omitted or altered. For this 35th anniversaryof Apollo 13, IEEE Spectrum spoke to some of the key figures in mission control to get the

real story of how they saved the day.

First, A Little Refresher on moon-shot hardware: a powerful, 85-meter tall, three-stage

Saturn V booster launched each mission from Cape Canaveral in Florida [see photo, To

The Moon]. Atop the Saturn V rode the Apollo stack, which was composed of two


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There were some batteries on board the command module, but these were intended for only afew hours use during re-entry, after the service module was jettisoned close to Earth.

With The Lunar Module's life support systems coming on line, the immediate threat of

death to the crew had been suspended, and it was time to start thinking about how to getthe astronauts home.

Jerry Bostick was the chief of the flight dynamics branch, the part of mission control that

looks after a spacecraft's trajectory--where it is, where it's going, where it should be, and

how to get it there. The controllers of the flight dynamics branch sat in the front row of

mission control, which they had proudly dubbed "the Trench." As they listened to the crew

in space and the systems controllers in the row behind them struggle with the explosion's

aftermath, "we went into the mode of okay, well, can we come back home immediately?"

remembers Bostick. The Trench soon calculated that if the crew used the Odyssey's main

engine and burned every last drop of fuel, they could turn around and come straight backto Earth, in a procedure known as a direct abort.

But the main engine was in the service module, and who knew what damage had been

done to it? It might malfunction: in the worst case, firing it up could result in another

explosion and kill the crew instantly. The other option was to let Apollo 13, carried forward

by its momentum and the moon's gravity, go around the moon. There, gravity would pull

Apollo 13 around the back side of the moon, accelerate it, and sling the spacecraft back

toward Earth. This journey would take several days, however, and the lunar module was

intended to support only two men for two days--not three men for four. If the crew didn't get

home fast, they could run out of power and die.Kranz says this was his toughest call on Apollo 13. "My team was pretty much split down

the middle. Many of my systems controllers wanted to get home in the fastest fashion

possible. The trajectory team did not want to execute a direct abort because it had to be

executed perfectly. If we didn't get the full maneuver, more than likely we would crash into

the moon," he explains, "I was of the frame of mind that said, 'Hey, we don't understand

what happened here...and if we execute a direct abort, we're not going to have much time

to think about it...We needed to buy some time so that when we did make a move, it would

be the proper move.' "

Weighing the concern that the Aquarius wouldn't cut it on a longer return journey, Kranztold Spectrum he had "a lot of confidence in my lunar module team." Apollo 13 was

Kranz's fourth mission involving a lunar module. "I knew it was a very substantial

spacecraft...I was pretty much betting that this control team could pull me out of the woods

once we decided to go around the moon."

Kranz made his decision. The main engine was out. Apollo 13 was going around the

moon.


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There was, of course, a fly in the ointment. During earlier Apollo missions, the outgoing

trajectory of the spacecraft had been selected so that if the service module's main engine

failed for any reason, the slingshot effect would aim the command and service module

perfectly at Earth, a so-called free-return trajectory. But this trajectory put very tight

constraints on the mission timeline, and for Apollo 13, it had been abandoned."We were on a non-free-return trajectory. If we did nothing, we'd whip back towards the

Earth but miss it by several thousand miles," the Trench's Bostick explains.

As the question of trajectory was being decided a shift change was going on at mission

control. When the explosion occurred, Kranz and his controllers--collectively known as the

White Team--had been about an hour away from the end of their shift. As was common,

most of the next shift--the Black Team, led by Glynn Lunney--had already shown up, so as

to be able to take over running the mission seamlessly from their predecessors, and they

had been on hand throughout the crisis.

As Kranz's team gathered up to leave mission control, Bostick went to speak to theincoming flight director, Lunney. By good fortune, Kranz and Lunney were perfectly

matched to the different phases of the crisis they would be faced with. Kranz was a

systems guy--he knew the internals of the spacecraft better than any other flight director,

the ideal person to cope with the second-by-second equipment failures and

reconfigurations triggered by the explosion. Lunney had come up through the flight

dynamics branch, making him ideally suited to get the spacecraft headed in the right

direction.

>"Kranz was there at the right time to make the decisions that had to be made rapidly, and

then, when Lunney took over he brought a calmness to the control center to do the right

things once they had gotten stabilized...They turned out to be a wonderful pair," says their

boss at the time, Kraft.

So Bostick speaking to the perfect audience when he voiced his concerns. "We need to

get this thing back to a free-return trajectory," Bostick told Lunney. Lunney instantly

agreed, but this left Bostick with a problem. Getting Apollo 13 onto a free-return trajectory

required a solid push from a big engine. With the Odyssey and Aquarius docked together

and the main service module engine out, that left only the engine attached to the lunar

module's descent stage, designed to be used only for the relatively short period of time

needed to land the Aquarius on the moon. "It was a problem, because we didn't have

capability in the control center to calculate the result of a docked maneuver" using the

descent engine, remembers Bostick.

During a mission, controllers called on a bank of mainframe computers in a Manned

Spacecraft Center facility set up and maintained by IBM, known as the Real Time

Computer Complex (RTCC), to calculate the length and direction of engine burns needed

to produce a given trajectory. To do these calculations, the mainframes were programmed


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his EECOM, Griffin ordered the command to be passed up to the crew immediately. The

corresponding switch was flipped onboard and valid telemetry was restored. With valid

data, Aaron could see that the fuel cells were off line, and with a second command to reset

the cells, Apollo 12 was on its way to moon. The incident cemented Aaron's reputation as

a "steely-eyed missile man."So, when Apollo 13 ran into trouble, Aaron was Aldrich's go-to guy. "I had a very good

group of people working for me at the time of the explosion, but we were scratching our

heads, and the very best person I had was John Aaron," says Aldrich.

After the explosion, Aldrich had moved into the spacecraft analysis, or SPAN, room,

located across from mission control. The SPAN room was fitted out with more consoles

and acted as a bridge between the flight controllers and the army of engineers who had

actually designed and built the spacecraft. "In there were supervisors like me and

executives from the engineering organizations in NASA and the manufacturers, and this

group would sit together and monitor the flights," says Aldrich. The SPAN room had comeinto being because "we learned during Mercury that we wanted immediate access to the

manufacturers, that we needed clear and unfiltered data very rapidly," says Kranz.

Over the phone, Aaron asked Aldrich to walk around behind the consoles in the SPAN

room and describe what he saw. "I started asking him: tell me what this measurement

says, tell me what that measurement says. And that went on for about ten minutes," says

Aaron.

In the data Aldrich read to Aaron, Aaron was looking for a pattern that would map to

failures in the instrumentation system onboard the Odyssey, but he was coming up empty.

"I told Arnie, 'Well, I'll be right there. In the meantime tell those guys they've got a real

problem on their hands,' " says Aaron.

As the lunar module controllers raced to power up the Aquarius, Aaron had made it in to

mission control. "When I walked in the room, I intentionally did not put a headset on

because I could see each of the flight controllers had zoomed in and were trying to sort the

problem out from the perspective of their individual subsystem," he says. He walked

behind the controllers, looked at their data, and listened to what they were saying to the

back rooms. Finally he sat down beside the embattled command and service module

controller Liebergot and plugged his headset in. "I said, "Sy, we've got to power the

command module down," recalls Aaron.

Aaron didn't just want the command module powered down to minimal systems only. He

meant powered down as in off. No guidance system, no heaters to keep back the cold of

space, no telemetry to help controllers diagnose the problem. Nothing. Aaron was

concerned that even a minimal power draw from the batteries would leave them with

nothing for re-entry.


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Aaron remembers debating with Gary Coen, one of the controllers with responsibility for

Odyssey's guidance system. "He was pleading with me to leave the heater circuit on in the

inertial platform in the CM," says Aaron. The inertial platform, which gave the computer

raw data about which way the spacecraft was pointing, was never designed to handle

extreme cold. "He said 'John, [the heater] only takes 0.4 amps..if we turn it off, the platformmay never work again.' And I said, 'Well, Gary, just do the math. 0.4 amps times 48 hours-

-we gotta turn it off. If it doesn't work again, we'll just have to figure out how to get home

without it.' "

But Without The Odyssey's Guidance System telling the crew precisely which way they

were pointing in space, how would they be able to align the spacecraft correctly to perform

the free-return trajectory maneuver?

The answer was to rely on the lunar module's guidance system, which had at its heart an

identical computer to the one in the Odyssey's guidance system. However, the lunar

module's guidance system had been powered off for most of the way to the moon--it hadno clue as to which way it was pointing. The crew would have to transfer the alignment

information manually from the command module's computer to the lunar module's

computer before pulling the plug in the Odyssey.

Doing so would require some good old-fashioned arithmetic. "You could read the angles

out of one computer and type them into the other, but you had to invert them," because the

Odyssey and Aquarius were docked head to head, and therefore pointed in opposite

directions, explains Aaron. The job fell to Lovell onboard the Aquarius, but "because I had

made mistakes in the arithmetic several times during sims..I asked the ground to confirm

my math," said the commander afterwards. The Trench broke out pencil and paper and

confirmed the angles.

As soon as possible after the crew aligned the lunar module's guidance system for the

free-return trajectory maneuver, they shut down the command module completely. In the

end, the inertial platform heater circuit breaker "was the last circuit breaker we pulled,"

says Aaron.

Now Aaron And The Other Members Of The Tiger Team were gathered in a room near

mission control. Kranz soon arrived and looked around the crowded space. The controllers

were subdued and shaken--they had failed to contain the crisis, and the crew was still in

extreme danger. But the last thing the astronauts needed was for controllers to begin

second-guessing themselves.

Confidence was part of the bedrock upon which mission control was built. When

prospective controllers joined NASA, often fresh out of college, they started out by being

sent to contractors to collect blueprints and documents, which they then digested into

information that mission controllers could use during a mission, such as the wiring

diagrams the lunar module controllers had used to figure out how to power up the


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Aquarius. After that, the proto-flight controllers started participating in simulations. The

principal problem NASA had with these neophytes was "one of self-confidence," explains

Kranz. "We really worked to develop the confidence of the controllers so they could stand

up and make these real-time decisions. Some people, no matter how hard we worked,

never developed the confidence necessary for the job." Those not suited for missioncontrol were generally washed out within a year.

Now Kranz feared his controllers, battered by the events of the last hour, would lose their

nerve. What happened next was a spectacular moment of leadership. "It was a question of

convincing the people that we were smart enough, sharp enough, fast enough, that as a

team we could take an impossible situation and recover from it," says Kranz. He went to

the front of the room and started speaking. His message was simple. "I said this crew is

coming home. You have to believe it. Your people have to believe it. And we must make it

happen," recalls Kranz.

In the Ron Howard movie, this speech was "simplified into 'Failure is not an option,' "chuckles Kranz, who never actually uttered the now famous phrase during the Apollo 13

mission. Still, Kranz liked it so much, because it so perfectly reflected the attitude of

mission control, that he used it as the title of his 2000 autobiography.

Kranz's speech electrified the room. "Everybody started talking and throwing ideas

around," remembers Aaron.

Kranz appointed three flight controllers as his key lieutenants. Aldrich was put in charge of

assembling the master checklist for powering the command module and other re-entry

procedures. A lunar module controller, William Peters, was ordered to make sure the

Aquarius lasted long enough to get the crew close to Earth. And Aaron was put in charge

of devising how electrical and other life support systems would be used so that as the crew

turned on the command module again prior to re-entry, they'd be able to get it up and

running and complete the descent through the Earth's atmosphere before the batteries

were exhausted.

Aaron's main problem was that, as with the Aquarius, powering up the command module

was a complex procedure, made even more difficult by the fact that, unlike the lunar

module, the Odyssey was never supposed to be powered down at any point during the

mission. "The only power-up sequence we knew was the one that started two days before

launch," Aaron remembers. But judging by what was left in the Odyssey's batteries, "we

had just a couple of hours at full power," he says.

Aaron listened to the hubbub of ideas on how to get the command module going and

decided it was time to step in. "I started throwing some ideas out as to how the power-up

sequence could be altered," he told Spectrum. Controllers immediately started to object,

explaining why it was vital that one aspect or another of the sequence remain untouched.


10/18

Aaron decided to chuck them all out of the room--with the exception of Jim Kelly, a

backroom command and service module controller who specialized in the electrical power

system--to give himself a chance to think. "I said 'Go get some coffee and come back here

in 45 minutes, and Jim and I will have a timeline of what we can turn on and when for a

rudimentary re-entry sequence."Aaron and Kelly took some paper and started sketching out a timeline, blocking out how

much power each system in the command module would use as it was brought on line.

"We didn't have any computer programs to do this," says Aaron. But, thanks to the

simulations, the pair had been trained in "all kinds of situations where power failures

happened. Mostly we were just sketching the timeline out from memory and what we had

learned from training," says Aaron.

The other controllers returned to find a big block diagram drawn on the blackboard. "They

came back in, and I started describing" the timeline, remembers Aaron, "That started the

brokering process, because every controller still wanted their favorite piece of equipmenton and the earlier the better."

The brokering process, with Aaron acting as the final arbiter, would continue for another

two or three days, refining the timeline and fleshing it out until the sequence was finally

ready. Aaron's work would raise his stock among his colleagues even higher. He "just had

a knack for the job...He was always thinking ahead, always capable of making the best of

a tough situation and getting us out of it," remembers Kraft.

Integrating the power-up sequence with other tasks that would have to be done before

entry into a set of procedures that could be read up to the crew was Aldrich's job. The

result, for a time the most precious document in the U.S. space program, started out as a

typewritten document, but as it was revised over and over, it was "updated in pen and

pencil...It was five pages long," says Aldrich, who still has the final checklist in his

possession. "I haven't looked at it in quite a long time. I know where it is, but it's buried!"

protested Aldrich when pressed for more details, revealing that he has kept quite a

scrapbook from his 46 years and counting in the space business.

Kranz's Tiger Team worked closely with the inhabitants of the Mission Evaluation Room

(MER), who were located in the building next to mission control. While the SPAN room

was designed to act as a communications conduit between mission control and the

engineers who had actually built and designed the spacecraft, the MER was where the

problems posed by mission control actually began to be solved.

The MER was established during the Mercury program. In the early days of the program,

the same people who built the spacecraft would staff the consoles in mission control. But it

turned out that "people didn't have time to be responsible for the engineering and also put

all the time in learning how to operate missions...so there was a split," says Aldrich. In

mission control was a "mission team, which really knew how the flight was to be executed,


11/18

what the possible trouble spots might be, and was prepared to deal with things that came

up, but it frequently would need more engineering help," to deal with questions that

cropped up concerning one piece of equipment or the other, Aldrich explains. In the MER

would be "an engineering team that was pretty well informed, but which wasn't directly

engaged with the flight on a first-hand basis," says Aldrich.The MER was big enough to house dozens of engineers and if a problem couldn't be

solved by those present, they could call on engineers throughout NASA's nationwide

network of RandD centers as well as the engineers of the contractors who built the

spacecraft. North American Aviation, based in Downey, Calif., (now part of Boeing Co.,

Chicago), built Apollo's command and service modules, while Grumman Aerospace, based

in Bethpage, N.Y., (now part of Northrop Grumman, Corp., Los Angeles), built the lunar

module.

As procedures for powering up the Odyssey or stretching the Aquarius's life support

system were developed in mission control, hundreds of engineers in California and NewYork would test them out in the same factories where the spacecraft were built.

"In Apollo 13 movie, you see Grumman," trying to hedge its support for some of the risky

tactics being employed by mission control, and "that did not happen," remembers Kranz,

who is otherwise "very pleased" with Ron Howard's movie. [To see what the other

controllers thought of the movie, see sidebar, "Mission Control at the Movies"]."The

contractor support was absolutely superb," says Kranz determinedly. "The contractors

knew what was at risk for every mission. If we had a problem and we turned to them, they

gave us everything we needed."

After Apollo 13 Performed the free-return trajectory maneuver using the lunar module's

descent engine, the debate went on about the fastest way to get the crew home. If no

changes were made to the trajectory, the crew would splash down in the Indian Ocean in

about four days. But there were no recovery forces to pick up the command module if it

ended up in that part of the globe.

Bostick and his flight dynamics controllers immediately began working on how to shave

some time off the return journey and have the splashdown happen in the Pacific, where all

the recovery forces had already been deployed. "We concluded we could do that fairly

easily and speed up [the splashdown] by about 12 hours, but we had also worked up an

option that would get back to the Pacific and speed it up by 36 hours," says Bostick. But

the 36-hour option would have involved jettisoning the service module immediately,

exposing the all-important re-entry heat shield to space for a long time, and required nearly

every drop of fuel left in the Aquarius's descent stage. Neither of these actions sounded

appealing.

In any case "by then the systems guys had really done a bang-up job of squeezing the

consumables" in the lunar module, says Bostick. They had done this principally by turning


12/18

off nearly every system in the Aquarius except for guidance, communications, and a

water/glycol cooling system that was needed to stop certain systems from overheating.

"Most of the water [onboard] was used for cooling; it was our most critical resource,"

explains Legler, who was the lead controller responsible for managing the Aquarius's

power and water usage. The two consumables were interrelated; the fewer systems thatwere turned on and drawing power, the less water would be needed for cooling. Normally,

fully powered up, the Aquarius's systems drew 50 to 75 amperes, and by dint of hard work,

"we powered it down to about 12 amps," says Legler. Twelve amps is about as much

power as a vacuum cleaner uses. Unfortunately for the crew there was no power in the

budget to run heaters to keep the crew warm, and temperatures inside the spacecraft

began to drop sharply.

With the Aquarius now expected to go the distance, the risky 36-hour option wasn't

needed, and the 12-hour maneuver was chosen.

This required another burn from the lunar module's descent engine, one that would takeplace 2 hours after Apollo 13's closest approach to the moon. The point of closest

approach was known aspericynthion, or PC for short, and so the trajectory adjustment was

called the "PC+2 burn."

The PC+2 burn needed to happen exactly right, and the Trench insisted the lunar module's

computer be used to control it. But the lunar module's guidance system used a lot of

power, and the Trench agreed that if they could use it for the PC+2 burn, they wouldn't ask

for it again. Almost exactly 24 hours after the oxygen tank explosion, the crew completed

the burn and shut down the navigation system. From here on out, the astronauts would be

flying by the seat of their pants.

As Apollo 13 sped toward Earth, mission control was beginning to worry about a new

problem. While the lunar module had enough spare oxygen to accommodate Swigert as

well as the intended lunar module crew of Lovell and Haise, carbon dioxide was beginning

to build up. Normally lithium hydroxide (LiOH) canisters absorbed the gas from the air and

prevented it from reaching dangerous levels, but the canisters onboard the Aquarius were

being overwhelmed. The Odyssey had more than enough spare LiOH canisters onboard,

but these canisters were square and couldn't fit into the holes intended for the lunar

modules' round canisters.

Mission control needed a way to put a square peg into a round hole. Fortunately, as with

the lunar module activation sequence, somebody was ahead of the game.


13/18

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14/18

miles off target, but it usually wasn't life threatening. But if Apollo 13 missed the trajectory it

needed to take to re-enter safely--known as the entry corridor--the results would be

disastrous as the command module skipped into space or burned up in the atmosphere. "If

you missed the entry corridor by a degree, that's a real bad day," says Bostick.

The crew was cold and exhausted by this point--temperatures on board had droppedalmost to freezing point. The astronauts had gotten very little sleep since the explosion,

and yet they pulled off the course-correction maneuver--and a second one a day later--

perfectly.

It Was Now over three days since the explosion in oxygen tank two. It was time to get

ready for re-entry. The first step was to recharge the batteries in the command module,

which had been significantly depleted before the lunar module came on line.

Remember how, while figuring out lunar module lifeboat procedures after the Apollo 10

simulation, Legler had worked out a way to run power from the lunar module to the

command module back along the electrical umbilicals that connected the spacecraft? Thatwas about to come in handy now, because that power could be used to recharge the

Odyssey's batteries.

"The biggest problem was that initially the lunar module guys didn't know how much power

they were going to need" for the Aquarius to serve its role as a lifeboat, remembers Aaron.

For the first 30 hours, Aaron's power-up team didn't think the lunar module guys were

going to have any power to spare for the Odyssey: about twelve hours after the explosion,

"we talked to them about getting some power," says Aaron. "They threw us out of the

room."

But the PC+2 burn had shortened Apollo 13's return flight sufficiently that the Aquarius

would be able to supply the power needed to charge the batteries. Working with North

American Aviation and Grumman, through lunar module gurus Hannigan and Mel Brooks

in the SPAN room, to refine the procedure, Legler and Bill Peters wrote up the needed

instructions. The charging process was "only 20 to 25 percent efficient," remembers

Legler, but it was enough.

But even with fully charged batteries, the Odyssey risked running out of electricity before it

splashed down. Batteries are rated using a term called ampere-hours. If you start with a 40

amp-hour re-entry battery, and then turn on a piece of equipment that uses 1 amp-hour,

and it takes 8 hours to finish the re-entry and splashdown, you have only 32 amp-hours left

to power everything else. But if you can delay turning on that piece of equipment until 2

hours before splashdown, now you have 38 amp-hours to go around. "It's not only a matter

of how large a load is, but how long that load is on for," says Aaron. Once a system had

been turned on in the Odyssey, it had to stay on, so "the only variable was how few

systems could we turn on and how late could we wait?" he explains.


15/18

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16/18

After being jettisoned from the command module, the Apollo 13 service module shows

extensive damage, with an entire panel of its outer skin blown away.

As part of the re-entry procedure, the crew jettisoned the damaged service module,

snapping pictures and beaming down video of the huge gash in the side of the module as

it tumbled into the distance [see photo, Accident's Aftermath]"There's one whole side ofthe spacecraft missing," radioed Lovell. "It looks like it got to the [main engine] bell, too,"

added Haise, validating Kranz's gut decision, four days earlier, to rule out using the main

engine and go around the moon.

Then it was time to abandon the Aquarius and strap into the command module. For the

lunar module controllers it was a bittersweet moment. "We were proud of the Aquarius and

very thankful--it had really performed, did everything we asked it to do" remembers Legler.

"It's hard to describe that feeling," says Hannigan, "thank God that we made it but..."

"Farewell, Aquarius, and we thank you," radioed Lovell back in 1970 as the astronauts

jettisoned the lunar module and watched it slowly drift away. Hannigan remembers hearingLovell's unbidden requiem for the spacecraft. "He did a good job," says Hannigan.

It was about another hour before the command module, headed for the Pacific, met the

first tenuous wisps of Earth's atmosphere. Soon, as the Odyssey plunged into the

atmosphere, those wisps would become a tremendous fireball of ionized air. The ionization

would block radio communications for several minutes. In the meantime, the heat shield

would be subjected to incredible temperatures and pressures, and if it had been cracked

during the explosion four days earlier, the crew would burn up without ever being heard

from again. Assuming the heat shield was okay, then the parachutes would deploy,

slowing the Odyssey to a gentle splashdown--if the parachutes hadn't been turned into

blocks of ice and the pyrotechnic charges intended to release them still worked. In a few

more minutes Lovell, Haise, and Swigert would either be home free, or dead.

But the astronaut's last words before re-entry were not for themselves. They were for

mission control. "I know all of us here want to thank all of you guys down there for the very

fine job you did," Swigert transmitted. "That's affirm," chimed in Lovell.

A few seconds later, the Odyssey disappeared into a sea of radio static.

By Apollo 13, NASA had a pretty good handle on radio blackouts during re-entry, and for a

given trajectory, it could work out how long--almost to the second--a spacecraft would be

out of touch. In the Odyssey's case, it was about 3 minutes.

The appointed time came and went, and as the seconds turned into minutes without any

sign of the Odyssey, the tension dragged out like a rusty blade through mission control.

"It was the worst time of the whole mission," agrees Kranz. "The blackout was a very

difficult time for every controller. You ask yourself 'did I give the crew everything I needed

to and was my data right?'...It was just a difficult time."


17/18

Bostick, the trajectory specialist, was in hell. "It was probably the worst I ever felt in my

life," he told Spectrum. "My feeling was 'oh my god, we have done the impossible: we got

them all the way home...and now something goes wrong in entry?...It was one of the most

depressing [times] of my life..." Bostick's voice wavers for a moment, the memory still

emotionally charged after thirty-five years. Then his voice strengthens into triumph, "butthen, when we heard from them, it was the happiest moment of my life," he declares.

An antenna-laden plane, circling in the air as part of the recovery effort, had picked up the

command module's signal: the crew had survived blackout! But even after radio contact

was re-established, the astronaut's lives were still in danger. The main parachutes still had

to be deployed. Kranz and the controllers stood rooted to their consoles, watching the

main display on the front wall of mission control. The Odyssey was going to splash down,

for good or ill, within sight of the live TV camera onboard the aircraft carrier leading the

recovery effort, the USS Iwo Jima.

Suddenly, the parachutes--three red and white canopies--blossomed into view on thescreen.

Pandemonium broke out in mission control. "I cried," says Kranz simply. "I think many of

the controllers did. The emotional release at that instant was so intense many of us were

unable to control our emotions. There were an awful lot of wet eyes that day."

Kraft was one of the few not swept away by the sight of the Odyssey gently descending

into the Pacific, suspending his celebration until the crew was safely onboard the Iwo Jima.

On seeing the deployed parachutes, "I felt fine," he remembers, "but I felt a lot better when

I saw them walking on the deck of the carrier. That's the way I always was. Too many

things could happen between the parachutes and the deck." Thirty-five years later, Kraft

ponders the memory of the crew walking in the open air on the Iwo Jima. "That was one of

the most excellent things I've ever seen," he finally says.

When The Crew and the flight controllers were finally reunited in Houston, there was,

naturally, a raucous celebration, the highlight of which was the playing of an audio tape

made by splicing together various mission control voice loop recordings. The creator was

merciless, lampooning almost everyone involved, and got a great deal of mileage from

Liebergot's "We may have had an instrumentation problem, Flight," and Kranz's later "I

don't understand that," sound bites.Despite President Nixon's award of the Presidential Medal of Freedom to those involved in

saving Apollo 13, few dwelt on its significance at the time. They were busy building on the

lessons learned from Apollo 13, and nine months later, Apollo 14 would blaze into the

skies above Florida as it left for the moon. Indeed for years, although many in mission

control viewed it as the highlight of their careers, they detected a sense of embarrassment


18/18

in NASA about the mission--they had failed to go the moon after all--a taint that wouldn't

fully be dispelled until the release of Ron Howard's movie in 1995.

Over the years that followed, the controllers left NASA one by one, leaving mission control

to a new crop of flight controllers. But a chain of excellence had been forged--to this day

every flight director in NASA has come up through the ranks. Each one studies the tradefrom flight directors who have also come up through the ranks--right back to the prototype

flight director, Chris Kraft, learning the values of discipline, competence, confidence,

shouldering responsibility, toughness, and teamwork, that form the foundation of mission

control's culture, demonstrated so abley during the Apollo 13 crisis.

Kraft still sees the culture he helped forge in evidence today at mission control. "I think

that's the one place in the space program that still has it," he says bluntly. "The people

who are running the control center today are just as good as we ever had, and I can't

praise them too highly."

While agreeing that today's flight controllers are top-notch, some of the other Apollo 13veterans worry their authority is being slowly undermined. "Over the years I've seen that

authority deteriorate badly," sighs Bostick, pointing to the management structure displayed

during the Columbia tragedy as a worrying example. There was a "team of program

managers who would meet every day and do flight planning: 'here's what we're going to do

today,' and they would pass that on to the flight directors, making the flight directors just

executors" of other people's decisions, Bostick says.

Aaron believes the problem stems from a lack of leadership from Capitol Hill on down.

Without an urgent and agreed upon goal--such as beating the Soviets to the surface of the

moon--NASA started being subjected to the conflicting demands of different individuals

and political camps in Congress, says Aaron, who worked at NASA Headquarters in

Washington, D.C., in the 1980s. NASA's marching orders have become "diffused and

muddled....That then affects NASA management, who instead of being technical gurus,

have to become amateur politicians." But--in what can only be good news for an agency

now planning to return to the moon after forty years absence--Aaron, who retired from

NASA in 2000, is convinced that the space program's engineers are still the best in the

business. At the grass roots level at least, we "still got the Right Stuff," he says.

Documents

As Apollo 13 Sped Toward Earth