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Digital Apollo : Human and Machine in Spaceflight Digital Apollo Digital Apollo: Human and Machine in Spaceflight David A. Mindell The MIT Press Cambridge, Massachusetts London, England ( 2008 Massachusetts Institute of Technology All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher. For information about special quantity discounts, please email [email protected] This book was set in Stone Serif and Stone Sans on 3B2 by Asco Typesetters, Hong Kong. Printed and bound in the United States of America. Library of Congress Cataloging-in-Publication Data Mindell, David A. Digital Apollo : human and machine in spaceflight / David A. Mindell. p. cm. Includes bibliographical references and index. ISBN 978-0-262-13497-2 (hardcover : alk. paper) 1. Human-machine systems. 2. Project Apollo (U.S.)—History. 3. Astronautics—United States—History. 4. Manned spaceflight—History. I. Title. TA167.M59 2008 629.47 04—dc22 2007032255 10987654321 For Pamela, who flies me to the moon. The machine, which at first blush seems a means of isolating man from the great problems of nature, actually plunges him more deeply into them. As for the peasant, so for the pilot, dawn and twilight become events of consequence. —Antoine de Saint-Exupe´ry, Wind, Sand and Stars Contents Preface and Acknowledgments xi 1 Human and Machine in the Race to the Moon 1 2 Chauffeurs and Airmen in the Age of Systems 17 3 Flying Reentry: The X-15 43 4 Airmen in Space 65 5 ‘‘Braincase on the tip of a firecracker’’: Apollo Guidance 95 6 Reliability or Repair? The Apollo Computer 123 7 Programs and People 145 8 Designing a Landing 181 9 ‘‘Pregnant with alarm’’: Apollo 11 217 10 Five More Hands On 235 11 Human, Machine, and the Future of Spaceflight 263 Notes 273 Glossary 305 Bibliography 307 Index 335 About the Cover Image 361 Preface and Acknowledgments On June 14, 1966, a robotic spacecraft had just landed on the moon and begun trans- mitting images to NASA. Project Gemini was drawing to a close, Apollo hardware was beginning to emerge from factories, and Apollo software was experiencing a crisis. And on that day I was born. I do not remember the first lunar landing of Apollo 11 or the drama of Apollo 13, but I do remember watching the later launches and landings on television. In that sense, I am among the first of a generation—those for whom lunar landings have always been a fait accompli—for whom the twentieth century’s greatest technological spectacle was an accomplishment rather than a dream. Nevertheless, as a boy I was fascinated by images of Apollo. When my father brought home a book, Apollo: Expeditions to the Moon, filled with wonderful, complicated imagery, I pored through it hundreds of times. The book shaped my lifelong fascination with machinery and my later choice to become an engineer. This book arises out of a later scholarly trajectory. It is the third in an unplanned tril- ogy, a series of books I have been writing since I chose to become a historian in 1991. For fifteen years, beginning with a study of the USS Monitor in the American Civil War, I have written about the relationship of humans and machines, the experiences of new technologies and their effects on human identity. My second book, Between Human and Machine: Feedback, Control, and Computing before Cybernetics, explored the history of hu- man interfaces, control systems, and digital computing. That book included an episode during World War II when Charles Stark Draper (and his young associate Robert Sea- mans) collaborated on a gun sight project with James Webb, then a lawyer for the Sperry Gyroscope Company. These three men would play central roles in the Apollo program. As I completed that book I found more and more continuities between the earlier history and the lunar landings. A project funded by the Sloan Foundation and the Dibner Foundation on the History of Recent Technology on the World Wide Web provided early support for collecting documents and interviews (that website is avail- able at http://digitalapollo.mit.edu). A senior research fellowship from the Dibner Insti- tute supported early writing. xii Preface and Acknowledgments A number of colleagues, friends, and students have been patient interlocutors and have read manuscripts in various states: Alexander Brown, Stephen Cass, Paul Ceruzzi, Don Eyles, Slava Gerovitch, Jeff Hoffman, Thomas P. Hughes, Chihyung Jeon, Rich Katz, Alex Kosmala, Roger Launius, John Logsdon, Fred Martin, Larry McGlynn, Dava Newman, Jim Nevins, Chuck Oman, Wayne Ottinger, Philip Scranton, Sherry Turkle, John Tylko, and Rosalind Williams. Paul Fjeld made incisive readings and a variety of documents from the Grumman Archives available from his personal collection; John Knoll generously created the cover image with historical help from Fjeld. Eldon Hall also generously shared documents and photographs, as did Hugh Blair Smith and Jim Nevins. Victor McElheny, as always, proved an engaging friend and also provided ac- cess to his collection of documents from his reporting on Apollo for the Boston Globe. Sarah Fowler assisted the research for the final stages of the manuscript with energy and humor. Thanks to Jack Garman for granting permission to produce the image from his Apollo 11 program alarm ‘‘cheat sheet,’’ and to the Society of Experimental Test Pilots for providing access to their back issues of journals and newsletters (some of them dug out of a closet). A number of Apollo participants generously gave their time for a series of group oral history interviews: Ramon Alonso, Dave Bates, Hugh Blair-Smith, Ed Blondin, Herb Briss, Ed Copps, Ed Duggan, Cline Frasier, Joe Gavin, John Green, Eldon Hall, Margaret Hamilton, David Hanley, David Hoag, Alex Kosmala, Dan Lickly, Fred Martin, Jim Miller, John Miller, Jack Poundstone, Herb Thaler, and Bard Turner. While writing this book I created a course at MIT, ‘‘Engineering Apollo: The Moon Project as a Complex System,’’ as an exploration of the project from numerous angles, from management techniques to software, from presidential policy to press coverage. I’ve been fortunate to teach in collaboration with Professor Larry Young from whom I have learned a great deal. We brought a wonderful mix of guests to class to create a unique educational experience for graduate students in engineering, management, and history: Buzz Aldrin, Dick Battin, Hugh Blair-Smith, Charlie Duke, Don Eyles, Joe Gavin, Eldon Hall, Sy Liebergot, John Logsdon, Victor McElheny, Ed Mitchell, Bob Parker, and Bob Seamans. A particularly interesting moment was attending a lunch with Chris Kraft, Bob Seamans, Aaron Cohen, and Jeff Hoffman. Each, through their generosity, memory, and insight, has contributed to my own thinking on Apollo. I have also been fortunate to serve on the NASA Historical Advisory Committee and to work with the NASA historians, archivists, and librarians without whom books like this would not be possible. These include Nadine Andreassen, Steve Dick, Steve Garber, Christian Gelzer, Mike Gorn, Roger Launius, Peter Merlin, Jane Odom, Curtis Peebles, Jennifer Ross-Nazal, Rebecca Wright, and the numerous interviewers who have col- lected NASA history since the 1960s. The NASA History Office preserves and publishes a history that, in addition to being central to spaceflight, exemplifies the evolution of a large technological system. Open and well documented, NASA’s systems are more ac- Preface and Acknowledgments xiii cessible to scholars than military or corporate ones, and hence provide crucial material for understanding the human evolution of technology. Only the second time I met my wife’s family, they accompanied me to the Cradle of Aviation Museum in Long Island and enjoyed a detailed tour of a lunar module. Their genuine interest and excitement made a warm welcome into the Getnick family that I will always remember. Pamela, whom I met and married while writing this book, sang me through it. I ded- icate the book to her, for laughing with me through every day and into our future. 1 Human and Machine in the Race to the Moon A July Day on the Moon On a July day in 1969, after a silent trip around the far side of the moon, the two Apollo spacecraft reappeared out of the shadows and reestablished contact with earth. The command and service module (CSM) (sometimes simply ‘‘command module’’) was now the mother ship, the capsule and its supplies that would carry the astronauts home. The CSM continued to orbit the moon, with astronaut Michael Collins alone in the capsule. ‘‘Listen, babe,’’ Collins reported to ground controllers at NASA in Hous- ton, ‘‘everything’s going just swimmingly. Beautiful.’’ His two colleagues Neil Arm- strong and Edwin ‘‘Buzz’’ Aldrin had just separated the other spacecraft, the fragile, spidery lunar module (LM, pronounced ‘‘lem’’), nicknamed Eagle, from the command module. This odd, aluminum balloon, packed with instruments and a few engines, would carry the two men down to the lunar surface. A rocket engine fired to slow the LM, causing it to fall out of orbit. Once on its way down, the spacecraft would either execute a dangerous abort or soon hit the moon. Whether the impact was a landing or a crash depended on the next ten minutes—the longest continuous series of critical events in the entire mission. In the LM, weight was such a premium that seats had been eliminated altogether. The astronauts stood up, stabilized by tensioned cables connected to the floor. The spacecraft was an enclosing home, complementing the astronauts’ bodies. It supplied their food, exchanged their gases, and collected their wastes. The human occupants, in turn, controlled flows of the spacecraft’s numerous fluids, drinking some for hydra- tion and carefully igniting others for propulsion.
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