O
ur group of fourteen astronauts, having successfully finished our jungle, desert, and classroom training, were now put to work. Al Shepard, the chief of the astronaut office, assigned each one of us a specific area of responsibility, in which we were to train ourselves to become experts. Buzz Aldrin was assigned mission planning, which meant he attended all the meetings on that subject. In 1964, we were trying to figure out how many flights in earth orbit we would need to make sure that we were ready to fly to the moon, and Buzz became our expert in planning these flights. His biggest problem was to calculate how many different kinds of rendezvous we
had to practice before trying a lunar landing. Once two men were on the moon, they could get back to earth only by making a successful rendezvous with their third partner waiting in orbit.
Bill Anders was assigned the environmental-control system, which is a fancy name for all the plumbing on board a spacecraft. Some pipes carry oxygen to breathe, others carry water to drink or to cool equipment. Then there are a lot of fans and pumps and storage tanks and other things which Bill had to understand. For example, he knew that a spacecraft flying between the earth and moon would be in constant daylight (“night” simply means that the earth is between us and the sun, making it dark where we are). Bill learned that if a spacecraft were held steady in this region, the side pointed toward the sun would get too hot, and the side in the shadow would get too cold. Therefore, the spacecraft had to be rotated, like a chicken on a barbecue spit, to distribute the heat from the sun evenly on all sides of it.
Charlie Bassett's specialty was the simulators. Simulators are make-believe spacecraft in which the crew practices and learns to fly the real ones. They are most important, because without them the astronauts would make all kinds of mistakes the first time they got into a real spacecraft. “Practice makes perfect,” according to an old saying. I certainly don't think I ever got perfect, but I know I wouldn't dare fly a real spacecraft without hundreds of hours of practice in a simulator. You can crash over and over again in a simulator without getting hurt, but your first crash in a spacecraft would be your last one.
Al Bean studied recovery systems, which means he had to learn all about the parachutes that lower the spacecraft gently into the ocean, and how the Navy frogmen would bring a raft alongside so that the crew could get out and into a helicopter, and how the spacecraft would then be hoisted aboard the aircraft carrier. Al Bean was a Navy pilot who had landed an airplane on a carrier many times, even at night and in bad weather.
Gene Cernan's area of responsibility was propulsion, which meant knowing about all the rocket engines a spacecraft carries. On Apollo, the lunar module has one rocket engine that slows it down enough to land gently on the moon, and a second one that boosts it back up into orbit. There are also a whole bunch of small rocket motors mounted in pairs around the outside of the spacecraft. These are fired briefly whenever the astronaut wants to change the direction in which the spacecraft is pointed.
Roger Chaffee's job was to learn the communications systemâthat is, all the radios and antennas on the spacecraft and on the ground. The three most important tracking stations on earth were located in Spain, Australia, and California. If you hold a small earth globe in your hands, you will see that, no matter which way you turn it, you will always be able to see either Spain or Australia or California. The idea was that as the earth turned on its axis, an astronaut on the moon would always be able to talk to Houston, if the radio waves were relayed through one of these tracking stations, depending on which one was pointed toward the moon at that particular time. Roger also had to learn about all the radios on board the spacecraft, because it was
very important that we be able to talk back and forth between the two Apollo spacecraft, as well as with the people on the ground.
Walt Cunningham studied the electrical systems, which were very complicated. Our spacecraft got its electricity from two sources: batteries and fuel cells. Batteries are familiar objects, found in automobiles and flashlights, but fuel cells are rare, and we didn't know much about them at first. In high-school science classes, the teacher sometimes shows how, if one passes an electric current through water (H
2
O), the water can be made to separate into two gases: hydrogen (H) and oxygen (O). A fuel cell does just the opposite. It takes two parts of hydrogen (H
2
) and one part of oxygen (O), puts them together, and gets water (H
2
O) plus electricity. That is really neat, because the crew can drink the water and use the electricity to run machinery, and the whole system weighs a lot less than using batteries and a separate drinking supply. The hydrogen and oxygen are cooled on the ground until they become liquid, and then they are stored on board the spacecraft in insulated tanksâlike giant thermos bottles. Oxygen must be really cold
(minus
293 degrees) to change from a gas to a liquid, but that is warm as an August swimming pool, compared to hydrogen's temperature as a liquid: minus 423 degrees!
Donn Eisele's specialty was the attitude and translation controls, and they are difficult to explain. Basically, the attitude controller on a spacecraft is like the stick on an airplane, and the translation controller is like an airplane's throttle. But it's more complicated than that. A throttle can just make an airplane go fast or slow in the same direction, but the translation controller, a handle sticking out of the
instrument panel, can make a spacecraft change speed in any direction: up-down and left-right, as well as straight ahead. You hold this handle in your left hand and push it in whichever direction you want to go. As long as you hold it in that direction, the proper rocket motors will fire to cause the spacecraft to move in that direction. The attitude controller looks like the end of a pilot's stick, and you hold it in your right hand just as you would in an airplane. It controls which way you are pointed. Just as in an airplane, if your nose is too far below the horizon, you pull the stick back, and vice versa. Same for keeping level with the horizon, by moving the stick left or right. But an airplane has rudder pedals also, and a spacecraft does not. The attitude controller can be twisted clockwise to move the nose right, and counterclockwise to make it go to the left, just like kicking the right or left rudder. With your left hand on the translation controller and your right on the attitude controller, you are ready to fly the spacecraft. Pretend that you are the pilot of an Apollo command module and you wish to dock with the lunar module. First find him, and move your right hand until he is exactly centered in your window. Then, using your left hand, thrust toward him until you are approaching at the proper rate, and holding the correct alignment with your right hand, use your left to reduce speed and bring your nose gently into his docking ring. Simple, isn't it? I hope you didn't hit him too hard.
Ted Freeman was the astronaut office's expert on boosters. Boosters are also called launch vehicles, or rockets, or missiles. I don't know which is the best name, but I usually call them boosters. The biggest one of all is the Saturn V, which we used to go to the moon. The Saturn IB
is a smaller version used for Apollo earth orbital flights, and the Titan II, smaller yet, was used to put the Gemini into orbit. Yet, compared to earth machines, even the midget Titan II is extraordinarily powerful, its two main engines each producing 215,000 pounds of thrust. If you gave your family car 215,000 pounds of thrust, it could accelerate from standing still to two hundred miles an hour in the length of a garage. And remember that the Titan II is a pygmy compared to the Saturn V. The Saturn V produces seven and a half
million
pounds of thrust. It gulps liquid propellants at the rate of 15 tons per second, which means that it could suck an average swimming pool dry in seven seconds. Ted Freeman's main worry was that one of these monster boosters might blow up and smash the spacecraft to smithereens. Fortunately, that has never happened with men on board, although plenty of unmanned rockets have exploded.
Dick Gordon's job was cockpit integration. He had to make sure all the dials and instruments and switches in the cockpit were properly located, so that the astronaut had all the information he needed, at the right time and in the right place. During launch or reentry, acceleration forces can cause an outstretched hand to weigh six or eight times as much as normal, and any switches needed at those times should be located where they can be easily seen and grabbed.
Rusty Schweickart's assignment concerned the experiments that would be flown aboard Gemini and Apollo. Flying to the moon was an experiment in itself, so not many experiments were carried on the early Apollo flights, but on Gemini we tried to carry as many experiments on board
as we possibly could. A lot of these involved cameras, taking pictures of the earth or sun or stars. Others were medical experiments, like seeing how many pulls on a huge rubber band it took to cause your heartbeat to double its usual rate. One even involved shaving parts of your head, to which electrical sensors were stuck, so that your brain waves could be recorded while you slept. We astronauts thought that was a silly one. The most complicated experiment I tried was to measure the angles between various stars and the earth's horizon, and from those angles to calculate where my spacecraft was, and how much we needed to change our orbit to rendezvous with an unmanned Agena rocket.
Dave Scott's job was guidance and navigation, which we called G&N for short. The Apollo G&N system kept track of where we were at all times. It measured our distance from earth, and our speed, and included an extremely accurate clock, so we would know when to make changes in our course. The G&N included a sextant, an instrument for looking at the stars and measuring their direction. We navigated using the stars and the horizon of either earth or moon. The G&N was the most complicated of all our systems, and Dave Scott had to be smart to understand it all. It also took a lot of hard work and study for the rest of us.
C. C. Williams's job was called range operations and crew safety. What that meant was that when a booster was launched from Cape Kennedy with men on board, there had to be complete agreement between the astronauts and the people on the ground. If an unmanned rocket started to veer off course, the range safety officer would simply push
a button and cause the rocket to blow up in mid-air, before it could fall down on houses or schools. But with astronauts on board, we wanted to make sure that as much warning time as possible was given to the crew, so they could separate their spacecraft from the booster, and that the destruct button, as it was called, would not be pushed unless it was absolutely necessary.
The specialty area I was assigned was pressure suits and EVA. Pressure suits, or space suits as they are better known, are what astronauts wear in space, and EVA stands for extra-vehicular activity; that is, working outside the spacecraft. EVA in earth orbit got called space walking, although it really isn't walking at all. It should be called something else, perhaps space floating or cord dangling, because we were always attached to the spacecraft by a safety line. I asked to be assigned to this work for a couple of reasons. First, I thought that learning about pressure suits would be fascinating work. Second, I thought that my math background was not as good as that of some of my fellow astronauts, and that I should avoid the very complicated areas like G&N.
What does a pressure suit do, and why do astronauts need them? The basic problem is that there is no air in space. It is a vacuum, which means that a person has nothing to breathe. Just as bad, there is no gas pressure pushing on his or her body, so that fluids inside the body would turn to gas, blood would literally bubble, and the person would die. Therefore, a pressure suit must do exactly what its name implies: it must keep pressure on the body. The gas we used was oxygen, so that not only was the astronaut's body protected, but he could also breathe the oxygen.
If the proper pressure and temperature of oxygen could be maintained at all times, then the astronaut would be set to venture outside his spacecraft.
Well ⦠almost ready, anyway. There are still a couple of other problems to solve. One is that the suit must be thick enough to protect the astronaut from the searing heat of the sun and the icy chill of space shadows. It must be strong enough to withstand the impact of a micrometeorite without losing pressure. It must be compact, light, and rugged. It must contain a communications system. Most difficult of all, it must be flexible and mobile. Think about a bicycle inner tube: it's nice and soft and floppy until you pump it up, when it forms a fairly rigid circle. Then, of course, it has to be encased inside a tire and rim, which holds its shape and protects it from punctures. A pressure suit is built in approximately the same way. There is a bladder of thin, soft rubber which acts as the inner tube. Then there is a restraint layer, which holds the bladder in and which conforms to the shape of the astronaut's body. Then there is an outer layer, to keep out meteorites and the sun's heat. The problem is that, unlike a bicycle tire, which always remains round, a pressure suit must constantly change shape. As the astronaut bends, it must bend; twist as he twists, and in general act as a tough outer layer of skin. Now, it is easy to move inside a suit that is deflated, like a floppy inner tube, but it gets to be hard work when the suit is pumped up, or inflated. Then the suit becomes rigid, and it is difficult to bend at the waist or elbow or shoulder. The suit designer must be part engineer and part magician to invent a suit that is safe and protective without being cumbersome and rigid.