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Digital Apollo

Digital Apollo: Human and Machine in Spaceflight

David A. Mindell
Copyright Date: 2008
Published by: MIT Press
Pages: 376
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  • Book Info
    Digital Apollo
    Book Description:

    As Apollo 11's Lunar Module descended toward the moon under automatic control, a program alarm in the guidance computer's software nearly caused a mission abort. Neil Armstrong responded by switching off the automatic mode and taking direct control. He stopped monitoring the computer and began flying the spacecraft, relying on skill to land it and earning praise for a triumph of human over machine. In Digital Apollo, engineer-historian David Mindell takes this famous moment as a starting point for an exploration of the relationship between humans and computers in the Apollo program. In each of the six Apollo landings, the astronaut in command seized control from the computer and landed with his hand on the stick. Mindell recounts the story of astronauts' desire to control their spacecraft in parallel with the history of the Apollo Guidance Computer. From the early days of aviation through the birth of spaceflight, test pilots and astronauts sought to be more than "spam in a can" despite the automatic controls, digital computers, and software developed by engineers. Digital Apollo examines the design and execution of each of the six Apollo moon landings, drawing on transcripts and data telemetry from the flights, astronaut interviews, and NASA's extensive archives. Mindell's exploration of how human pilots and automated systems worked together to achieve the ultimate in flight--a lunar landing--traces and reframes the debate over the future of humans and automation in space. The results have implications for any venture in which human roles seem threatened by automated systems, whether it is the work at our desktops or the future of exploration.David A. Mindell is Dibner Professor of the History of Engineering and Manufacturing, Professor of Engineering Systems, and Director of the Program in Science, Technology, and Society at MIT. He is the author of Between Human and Machine: Feedback, Control, and Computing before Cybernetics and War, Technology, and Experience aboard the USS Monitor.

    eISBN: 978-0-262-26667-3
    Subjects: Technology

Table of Contents

  1. Front Matter
    (pp. i-viii)
  2. Table of Contents
    (pp. ix-x)
  3. Preface and Acknowledgments
    (pp. xi-xiv)
  4. 1 Human and Machine in the Race to the Moon
    (pp. 1-16)

    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 Houston, “everything’s going just swimmingly. Beautiful.” His two colleagues Neil Armstrong and Edwin “Buzz” Aldrin had just separated...

  5. 2 Chauffeurs and Airmen in the Age of Systems
    (pp. 17-42)

    The Society of Experimental Test Pilots (SETP) held its first annual awards banquet on October 4, 1957. These men sat at the top of the piloting profession, crossing the border between engineering and flying skills. They had been rocketed to fame by Chuck Yeager’s epochal supersonic flight nine years before. The atmosphere in the banquet hall was electric as the group celebrated its new society epitomizing professional maturity. Six hundred and fifty people attended, many of them making the drive from the dry desolation and professional focus of Edwards Air Force Base, a few hours north in the Mojave desert,...

  6. 3 Flying Reentry: The X-15
    (pp. 43-64)

    In October 1954, the NACA Committee on Aerodynamics held its biannual meeting. Chairing the group was Preston Bassett, president of the Sperry Corporation, the pioneering control systems company that developed automatic pilots, gyroscopes, and a host of other aircraft instruments. The committee also included leading lights of aeronautics: Clark Millikan, the aerodynamicist from Caltech, Allen Puckett, a guided missile pioneer from Hughes Aircraft, helicopter designer Bartram Kelley, and a variety of other notable academic and industry representatives, including decision makers from the U.S. Air Force and Navy. Their meeting lasted two days, the first at the NACA Ames Research Center...

  7. 4 Airmen in Space
    (pp. 65-94)

    In May 1961, a year and a half after the X-15’s first flight, Alan Shepard became the first American to fly in space. He flew not in a rocket plane but atop a Redstone ballistic missile. Public response to Mercury quickly overshadowed the X-15, and missiles superseded aircraft as the first stage of human delivery into space. But the human role was far from settled. As Joachim Kuettner, a former test pilot and member of Wernher von Braun’s engineering team, described above, human spaceflight in the United States required merging two technologies.¹ Each had developed an engineering culture of shared...

  8. 5 “Braincase on the tip of a firecracker”: Apollo Guidance
    (pp. 95-122)

    When John F. Kennedy took office in January 1961, human spaceflight did not appear on his political radar screen. Kennedy’s science advisors believed that emphasizing human flights would overshadow the country’s strengths in space science. They recommended the president distance his administration from Mercury, an expensive and potentially dangerous holdover from the Eisenhower administration that had received a great deal of attention but had not yet flown with a human aboard. NASA had been working on a lunar program for two years, as a technical extension of earth-orbital work, holding industry conferences and letting study contracts, but the political support...

  9. 6 Reliability or Repair? The Apollo Computer
    (pp. 123-144)

    While “mini” computers were beginning to come on the scene in the 1960s, the word was still relative, and a small computer was still the size of a phone booth. Specialized machines, like the seven-function unit that ran rendezvous calculations for Gemini, or the ballistic solvers in the Polaris missile, could be made reasonably compact, but the IL engineers envisioned a “general-purpose” computer, one that could be reprogrammed at will to do any possible task with the data at hand.

    Such a machine afforded great possibilities. New, specialized functions could be added at any time, merely by changing the programs,...

  10. 7 Programs and People
    (pp. 145-180)

    With the exception of integrated circuits and extremely high reliability, the hardware for the Apollo guidance computer represented the state of the art when Apollo began. The same could not be said of the software and user interface. An aspect of the system barely envisioned when the program started, software turned out to be among the most difficult, and the most critical, components in the Apollo system. The software would carry all the burden of Richard Battin’s complex guidance schemes. It would embody the goals and constraints of specific missions, and hence would require special finesse (sometimes completely new programs)...

  11. 8 Designing a Landing
    (pp. 181-216)

    This book began with a detailed description of the Apollo 11 landing, focusing on the human-machine interaction. We now revisit the landings as the culmination of the debates over pilots’ roles, computer engineering, software, and human abilities. This focus necessarily excludes a great deal of the Apollo flights, but the landings represented critical moments of each mission. Neil Armstrong described them as “the hardest for the system and hardest for the crews.” On a scale of one to ten, Armstrong rated walking around on the moon a one, whereas “the lunar descent on a ten scale was probably a thirteen”...

  12. 9 “Pregnant with alarm”: Apollo 11
    (pp. 217-234)

    Apollo 11 was a test flight whose major goal was simply to prove the feasibility of lunar landing with the Apollo system. Most aspects of the flight to the moon had been tried before. Apollo 10 had gone right down to 50,000 feet and then returned home, only a PDI burn remaining between it and the lunar surface. Yet from that point downward everything was new on Apollo 11—accomplished many times before, but only in simulation. The Apollo 11 landing was the climax of the development program, of Apollo’s methods of integrating the efforts of diverse organizations into a...

  13. 10 Five More Hands On
    (pp. 235-262)

    Apollo 11 accomplished a dramatic first that was difficult to replicate, both in technical suspense and public response. Still, it was only the beginning of the program, the first of six landings. Nor was it alone in raising new tensions and synergies between human and machine. Throughout the social-technical system that was Apollo, skill, experience, and risk migrated across human and machine boundaries. The social and the technical traded off, complemented each other, made up for each other’s weaknesses. In the real-time pressure of a lunar landing, an extensive social network of engineers focused on two men and a computer...

  14. 11 Human, Machine, and the Future of Spaceflight
    (pp. 263-272)

    In 1963 Joe Shea addressed the second Manned Space Flight Meeting of the American Institute of Aeronautics and Astronautics (AIAA). He explained the “systems view” that had originated in Bell Telephone Laboratories and in the U.S. Air Force’s ballistic missile programs and was now pervading NASA’s upper administration. As the paramount example of this philosophy, Shea offered NASA’s approach to the human-machine relationship, “one area in danger of being overwhelmed by dogma.” Systems engineering, he argued, could help engineers move beyond that dogma.¹

    Shea granted that both humans and machines had critical roles to play in space missions. While human...

  15. Notes
    (pp. 273-304)
  16. Glossary
    (pp. 305-306)
  17. Bibliography
    (pp. 307-334)
  18. Index
    (pp. 335-360)
  19. About the Cover Image
    (pp. 361-361)