|DECEMBER 2006 / JANUARY 2007 – NO. 11|
Apollo 13 was launched on schedule, at 13:13 Houston time on April 11, 1970, and three hours later blasted out of Earth orbit toward the moon. For Jack Swigert and Fred Haise, neither of whom had ever been in space before, the experiences of launch and orbit and translunar burn were inexpressibly novel. For Jim Lovell, making his fourth trip atop a rocket (and his second atop the immense Saturn 5), it was little more than a return to business. On the first full day of the mission, the lunar veteran, now occupying the exalted left-hand seat that Frank Borman had claimed a year and a half earlier, called down to Earth for some of the idle banter that he and Borman and Bill Anders had come to look forward to during their week in space in 1968.
"Hello there, Houston, 13" Lovell said.
"13, Houston, go ahead," answered the Capcom. As on all flights, the Capcoms assigned to work this one were other astronauts, the thinking being that three men in a can zipping along at 25,000 miles an hour would just as soon do their talking to a fellow traveler and not some technician who had never graduated beyond the coach seat of a commercial jet. The Capcom today was Joe Kerwin, one of NASA's greener novices. Kerwin had never yet flown in space, but the flight manifests all said that one day he would, and that's what counted.
"We'd almost forgotten," Lovell said to Kerwin. "We'd like to hear what the news is."
"OK, there's not a whole lot to it," Kerwin said. "The Astros survived, eight to seven. The Braves got five runs in the ninth inning, but they just made it. They had earthquakes in Manila and other areas of the island of Luzon. West German Chancellor Willy Brandt, who witnessed your launch from the Cape yesterday, and President Nixon will complete a round of talks today. The air traffic controllers are still out, but you'll be happy to know the controllers in Mission Control are still on the job."
"Thank goodness for that." Lovell laughed.
"Also," Kerwin went on, "some truck lines are being struck in the Midwest, some schoolteachers have walked off the job in Minneapolis. And of course today's favorite pastime across the country … " Kerwin paused for dramatic effect. "Uh-oh, have you guys completed your income tax?"
Swigert, sitting in the center couch, cut into the loop. "How do I apply for an extension?" he asked, his voice businesslike, unamused. Kerwin, who knew he had hit his mark, laughed. "Joe, it ain't too funny," Swigert protested. "Things happened kinda fast down there and I do need an extension." A few other controllers could now be heard laughing on the line. "I'm really serious," Swigert said. "I didn't get mine filled."
"You're breaking up the room down here," Kerwin said.
"Well," grumbled Swigert, "I may be spending time in another quarantine when we get back, besides the medical one they're planning for us."
"We'll see what we can do, Jack," said Kerwin. "In the meantime, the uniform of the day for you guys will be in-flight coverall garments with sword and medals, and tonight's movie, shown in the lower equipment bay, will be John Wayne, Lou Costello, and Shirley Temple in 'The Flight of Apollo 13.' Over."
That the crew and the ground could spend so much of their time engaging in such ship-to-shore small talk still occasionally amazed Lovell. There would be no movie on the flight, of course, and there would be no swords or medals or uniform of the day. But playful references to the slow-paced life aboard a roomy, cruising Navy ship was not lost on the ex-Annapolis man. The joke in the old Mercury days was that astronauts didn't climb into their capsules, they put them on. The spacecraft were preposterously small and uncomfortable, and the missions lasted an average of just eight and a half hours. In the Gemini capsule were Lovell had cut his orbital teeth, there was about twice the interior space, but also twice the number of occupants.
As Lovell had discovered in Apollo 8, and as Haise and Swigert were now learning, NASA's lunar ships were an entirely different engineering animal. The Apollo command module was an 11-foot-tall cone-shaped structure, nearly 13 feet wide at the base. The walls of the crew compartment were made of a thin sandwich of aluminum sheets and an insulating honeycomb filler. Surrounding that was an outer shell of a layer of steel, more honeycomb, and another layer of steel. These double bulkheads — no more than a few inches thick — were all that separated the astronauts inside the cockpit from the near-absolute vacuum of an outside environment where temperatures ranged from a gristle-frying 280 degrees Fahrenheit in sunlight to a paralyzing minus 280 degrees in shadow. Inside the ship, it was a balmy 72.
The astronauts' couches lay three abreast and were actually not couches at all. Since the crew would spend nearly the entire flight in a state of weightless float, they needed no padding beneath them to support their bodies comfortably; instead, each so-called couch was made of nothing more than a metal frame and a cloth sling — easy to build and, more important, light. Each couch was mounted on collapsible aluminum struts, designed to absorb shock during splash-down if the capsule parachuted into the sea — or, in the case of a mistargeted touchdown, onto land — with too much of a jolt. At the foot of the three cots was a storage area that served as a sort of second room (Unheard of! Unimaginable in the Gemini and Mercury eras!) called the lower equipment bay. It was here that supplies and hardware were stored and the navigation station was located.
Directly in front of the astronauts was a big, battleship-gray, 180-degree instrument panel. The 500 or so controls were designed to be operated by hands made fat, slow, and clumsy by pressurized gloves, and consisted principally of toggle switches, thumb wheels, push buttons, and rotary switches with click stops. Critical switches, such as engine-firing and module-jettisoning controls, were protected by locks or guards, so that they could not be thrown accidentally by an errant knee or elbow. The instrument panel readouts were made up primarily of meters, lights, and tiny rectangular windows containing either "gray flags" or "barber poles." A gray flag was a patch of gray metal that filled the window when a switch was in its ordinary position. A striped flag like a barber pole would take its place when, for whatever reason, that setting had to be changed.
At the astronauts' backs, behind the heat shield that protected the bottom of the conical command module curing reentry, was the 25-foot cylindrical service module. Protruding from the back of the service module was the exhaust bell for the ship's engine. The service module was inaccessible to the astronauts, in much the same way the trailer of a truck is inaccessible to the driver sitting in the cab. (Since the windows of the command module faced forward, the service module was invisible to the astronauts as well.) The interior of the service module was divided into six separate bays, which contained the entrails of the ship — the fuel cells, hydrogen tanks, power relay stations, life-support equipment, engine fuel, and the guts of the engine itself. It also contained — side by side, on a shelf in bay number four — two oxygen tanks.
At the other end of the command module-service module stack, connected to the top of the command module's cone by an airtight tunnel, was the LEM. The four-legged, 23-foot tall craft had an altogether awkward shape that made it look like nothing so much as a gigantic spider. Indeed, during Apollo 9, the lunar module's maiden flight, the ship was nicknamed "Spider," and the command module was called by an equally descriptive "Gumdrop." For Apollo 13, Lovell had opted for names with a little more dignity, selecting "Odyssey" for his command module and "Aquarius" for his LEM. (The press had erroneously reported that Aquarius was chosen as a tribute to Hair — a musical Lovell had not seen and had no intention of seeing. The truth was, he took the name from the Aquarius of Egyptian mythology, the water carrier who brought fertility and knowledge to the Nile valley. Odyssey he shoes because he just plain liked the ring of the word, and because the dictionary defined it as "a long voyage marked by many changes of fortune" — though he preferred to leave off the last part.) While the crew compartment of Odyssey was a comparatively spacious affair, the lunar module's crew compartment was an oppressively cramped, seven-foot eight-inch sideways cylinder that featured not the five portholes and panoramic dashboard of the command module but just two triangular windows and a pair of tiny instrument panels. The LEM was designed to support two men, and only two men, for up to two days. And only two days.
NASA was extremely proud of this pair of spacecraft and liked to show them off. Since the triumphant success of the Apollo 8 broadcasts two Christmases ago, crews had continued to go aloft with television cameras stowed in their equipment bays and with time for live broadcasts written into their flight plans. The practice reached its peak of popularity during the Apollo 11 moon landing in the summer of 1969, when stations around the globe carried Neil Armstrong and Buzz Aldrin's first tentative moonwalk and most of the world stood still to watch it. But by the time Apollo 13 rolled around, the world had lost interest. A little after the two-day mark in the mission, the crew was scheduled for its first TV show, but none of the networks intended to carry it. The broadcast was set to begin at 8:24 pm on Monday, April 13, in the time slot belonging to NBC's Rowan & Marin's Laugh-In and CBS's Here's Lucy. ABC had programmed the 1966 movie Where Bullets Fly, followed by The Dick Cavett Show.
Viewers across the nation had shown little interest in having any of these programs preempted by the show from space, and even in Mission Control, NASA technicians themselves were only half interested. The broadcast would begin an hour and a half before the afternoon-evening shift punched out, and most of the men at the consoles were already looking forward to finishing their workday and stopping for a drink at the Singin' Wheel, a red-brick, antiques-stuffed saloon just off the Space Center compound.
NASA and the Apollo crew nevertheless decided to go ahead with the show and to make the feed available to any stations that might want to tape bits of it for their eleven o'clock news shows. A little coverage, they figured, was better than no coverage at all. Besides, the wives of the astronauts had come to look forward to these periodic broadcasts, and nobody in NASA wanted to tell them that the custom would be discontinued. Already tonight, the controllers in Houston could see that Marilyn Lovell and two of her four children, 16-year-old Barbara and 11-year-old Susan, had settled into the cushioned seats in the glassed-in VIP gallery at the rear of Mission Control. Also with them was Mary Haise, the wife of the first-time astronaut, preparing to watch as her husband's image was beamed down from space.
The program that nobody buy Marilyn, Barbara, Susan, Mary, and the controllers saw began with a choppy, murky image of Fred Haise drifting up toward the tunnel connecting the command module and the LEM. Lovell was reclining on Swigert's couch in the middle of the command module, operating the camera. Swigert had shifted left to Lovell's couch.
"What we plan to do for you today," Lovell said to nobody but Houston, "is start out in spaceship Odyssey and then take you on through the tunnel to Aquarius. Your TV operator is now resting on the center couch looking at Fred, and Fred will now transport himself into the tunnel, and we'll show you a little bit of the landing vehicle."
Haise obliged for the camera, floating through the cone of the command module and emerging into the LEM, descending head-first through the ceiling like a cross-dimensional traveler entering another world through whatever time-space portal happened to be available. Lovell floated slowly after him.
"One thing I noticed, Jack," said the upside-down Haise to his Capcom, "was that starting upright in the command module and heading down into Aquarius, there's an orientation change. Even though I'd practiced it in the water tank, it's still pretty unusual. I find myself now standing with my head on the floor when I get down into the LEM."
"That's a great picture, Jim," Jack Lousma, the Capcom, encouraged the commander. "You got the light just right."
Lovell entered the LEM, flipped his position, and descended feet-first onto a large bulge in the floor of the module. "For the sake of all the people back home," said Haise, "housed inside this can under Jim's feet is the LEM ascent engine, the engine that we use to get off the moon. Immediately adjacent to the engine cover here, I have my hand on a white box. This happens to be Jim's backpack, which will supply oxygen and water for cooling while on the lunar surface."
"Roger, Fred, we see it," said Lousma. "The picture's coming through real good and your description is good. We see Jim's got the camera oriented the way we like to look as it, so keep talking."
Lovell and Haise cheerfully complied, sending their good picture and good descriptions back to Earth. While the show proceeded in its folksy way, much of Mission Control was busy with other things. On the closed communications loop intended for the people at the consoles only, most of the controllers were planning maneuvers the crew would perform as soon as they signed off the air. Kranz, the flight director, led the discussions, refereeing requests, setting priorities, and determining which exercises were essential and which would wait. The chatter on this loop would have made decidedly less sense to Earth-bound observers than the TV show intended for their consumption.
"Flight, EECOM," Liebergot called into the loop.
"Go ahead, EECOM," Kranz said.
"At 55 plus 50, we would sure like to have a cryo stir. All four tanks."
"Let's wait until they get settled down some more."
"Flight, GNC," signaled Buck Willoughby, the guidance, navigation, and control officer.
"Go ahead, GNC."
"We would like to reenable the other two quads for the maneuver."
"You want them to enable C and D, right?"
"You want them to disable A and B?"
"OK, all four quads."
"Flight, INCO," said the instrumentation and communications offer.
"I would like to confirm the configuration of their high gain now. We would like to know what track mode they're in."
"OK, let's just stand by one there."
The maneuvers Houston was planning for the crew, for all their technochatter sound, were fairly routine. The INCO's reference to the "high gain" concerned the service module's main antenna, which had to be transmitting on a particular frequency and set as at particular angle depending on the position and trajectory of the spacecraft. Charged with the round-the-clock job of monitoring the ship's communications systems, the INCO needed to check periodically to make sure everything was oriented as it should be. The business with the quads concerned the four clusters of attitude-control thrusters arrayed around the service module which moved the ship from one position to another. The crew was going to make some navigational shifts after the TV show, and the GNC wanted all four sets of thrusters up and running.
The other exercise, the "cryo stir" Liebergot requested, was perhaps the most routine of all. The service module was equipped with not only two oxygen tanks but also two hydrogen tanks, all of which maintained their gases in a hypercold, or cryogenic, state. The temperature, which in the case of the oxygen tanks could drop as low as minus 340 degrees Fahrenheit, kept the gases at what is known as supercritical density — a chemically queer condition in which a material is not quite a solid, not quite a liquid, and not quite a gas, but something slushily in between. So well were the tanks insulated that if they were filled with ordinary ice and placed in a 70-degree room, it would take eight and a half years for the ice to melt down to water just above the freezing point, and another four years for the water to rise to room temperature. That's what the designers liked to claim, in any case, and since nobody would ever actually run this test, NASA took them at their word.
The real magic of the cryogenic tanks, however, was not what happened to the oxygen and hydrogen tanks while they were still inside the vessels, but what happened when they were channeled out. The tanks were connected to three fuel cells equipped with catalyzing electrodes. Flowing into the cells and reacting with the electrodes, the two gases would combine and, in a happy coincidence of chemistry and technology, produce a trio of byproducts: electricity, water, and heat. From just two gases, the cells would produce three consumables no life-sustaining spacecraft could do without.
Although the oxygen and hydrogen tanks were equally important in keeping the ship alive and thrumming, the oxygen tanks were especially precious because they also contained virtually all of the crew's supply of breathable air. Each of the two tanks was a sphere 26 inches in diameter, holding 320 pound of oxygen at a pressure of up to 935 pounds per square inch. Immersed in the tank, like fingers testing the temperature of a tubful of bath water, were two electrical probes. One, running the length of the tank from top to bottom, was a combination quantity gauge and thermostat; the other, adjacent to it, was a combination heater and fan. The heater was used to warm and expand the oxygen in case the pressure in the tank dropped too low. The fans were used to stir the stuff up — something an EECOM would request at least once a day, since supercritical gases tend to stratify, confounding the tanks' quantity probes.
While Liebergot waited for his stir and the other controllers planned further procedures, the crew continued its television tour. On the large monitor at the front of Mission Control, a milky image of the moon appeared, evoking memories of the Apollo 8 broadcasts, when the whole world had been watching.
"Out the right window now," said Lovell, the narrator, "you can see the objective, and I'll zoom in on it and see if this brings it in better."
"It's beginning to look a little bigger to us now," said Haise. "I can see quite distinctly some of the features with the naked eye. So far, though, it's still looking pretty gray, with some white spots."
Lovell then swung the camera back inside the LEM. On the screen, Haise appeared to be making adjustments to a large cloth sling of some kind. "Now we can see Fred engaged in his favorite pastime."
"He's not in the food locker, is he?" asked Lousma.
"That's his second-favorite pastime," said Lovell. "Now he's rigging his hammock for sleep on the lunar surface."
"Roger. Sleeping and then eating."
Lovell pushed away from Haise and began to drift back toward the tunnel. "OK, Houston," he said, "for the benefit of the television viewers, we've just about completed our inspection of Aquarius, and now we're proceeding back into Odyssey."
"OK, Jim. We think you ought to conclude it from here now, but what do you think?"
"Anytime you want to terminate, we're all set to go," Lovell agreed. Having played to a nearly empty room for some 27 minutes now, he allowed more than a little relief to creep into his voice. "We've just got to put the cabin repress valve in."
"Roger," Lousma said.
The repress valve was a lunar module control used to help maintain equal pressure between the two spacecraft. Hearing the exchange, Haise helpfully turned the valve, causing a sudden hiss and thump to rock both ships. Holding the camera, visibly flinched. Earlier in the mission, the commander had begun to suspect that his over-exuberant crewmate sometimes used the repress valve more than was strictly necessary, deriving mischievous pleasure from the startle effect it had on his two crewmates. Here in their third full day, the joke had grown the tiniest bit frayed.
"Every time he does that," Lovell said candidly, "our hearts jump in our mouths. Jack, anytime you want to terminate TV, we're all set to go."
"Ok, Jim," Lousma concluded. "It's been a great show."
"Roger," said Lovell. "Sounds good. This is the crew of Apollo 13, wishing everyone there a nice evening. We're just about ready to close out Aquarius and get back for a pleasant evening in Odyssey. Good night."
And the projection screen went blank.
Excerpt from Apollo 13, by Jim Lovell and Jeffrey Kluger. Copyright © 1994 by Jim Lovell and Jeffrey Kluger. Reprinted by permission of Houghton Mifflin Co.