Apollo Guidance Computer Concepts

The Everything Blueprint: The Microchip Design That Changed the World

by James Ashton · 11 May 2023 · 401pp · 113,586 words

domestic product (GDP) was ploughed into research and development. Offering vastly improved processing power, these relatively small and lightweight devices found a home in the Apollo Guidance Computer (AGC) installed on board each of the command modules in the space programme that led up to the 1969 moon landing. State support didn’t

Digital Apollo: Human and Machine in Spaceflight

by David A. Mindell · 3 Apr 2008 · 377pp · 21,687 words

true if you measure a computer’s capability in memory capacity or machine cycles alone. But if you consider interconnections, reliability, ruggedness, and documentation, the Apollo guidance computer is at least as impressive as the PC on your desktop, and the Apollo software an equally intricate ballet of many people’s work and

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. Gilbert remembered a tough decision: ‘‘I guess the first bad move I made against MIT.’’66 118 Chapter 5 Figure 5.5 The Block II Apollo guidance computer crew station in the command module. Note the eyepieces for the space sextant and scanning telescope (top), the hand controls for aligning the sights (middle

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life-critical application. 124 Chapter 6 From 1962 to 1965, NASA and IL engineers struggled through these problems as they developed the hardware for the Apollo Guidance Computer (AGC). At odds were differing engineering cultures, differing technical philosophies, and differing visions of the astronauts’ roles. The design decisions, while considering subtle, technical details

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he set about designing and building a MicroLogic-based computer that would run the same instructions as the Mod 3C, and named it AGC for ‘‘Apollo guidance computer.’’ The name would stick. Logic designers Ray Alonso, Hugh Blair-Smith, and Albert Hopkins saw the redesign as ‘‘an unusual second chance’’ to tweak their

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systems integrator, but without cognizance over the contractors or authority over production hardware. ‘‘Weak systems thinking’’ The Block II redefinition had great import for the Apollo guidance computer (AGC) and hence for the human role in the missions. First to go was the idea that the astronauts might repair the system in flight

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The Digital Autopilot Shea made one other change in the control system for the Block II design. When he came to Houston from headquarters, the Apollo guidance computer was just that—a computer that figured out where the spacecraft was and where it ought to go. Another system actually took care of commanding

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.’’ —Opening lines of Apollo software source code Programming the Moon Flights 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

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. A series of warning and indicator lights (including the feared GIMBAL LOCK) 166 Chapter 7 Figure 7.8 DSKY—display and keyboard unit—for the Apollo guidance computer. Note the space for digital displays on the right, with program, verb, and noun indicators, and three line numerical display below. Also note status lights

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through the computer to fire the thrusters, which is not too different from the computer doing that itself. You feel different, though. —David Scott, ‘‘The Apollo Guidance Computer: A User’s View’’ Apollo 11 accomplished a dramatic first that was difficult to replicate, both in technical suspense and public response. Still, it was

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History of the AGC Integrated Logic Circuits.’’ 13. Chilton interview with Bergen. 14. Faget interview with Ertel, 7. 15. Hall, ‘‘General Design Characteristics of the Apollo Guidance Computer,’’ appendix III. 16. Frasier, HRST1. 17. John French to C. W. Frick, ‘‘Apollo Navigation and Guidance System Trip Report,’’ March 30, 1962, UHCL Chrono 62

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correspondence. 20. Partridge, Hanley, and Hall, ‘‘Progress Report on Attainable Reliability of Integrated Circuits for Systems Applications,’’ 7. 21. Hall, ‘‘General Design Characteristics of the Apollo Guidance Computer.’’ 22. Sato, ‘‘Local Engineering in the Early American and Japanese Space Programs,’’ 87–88. Notes to Pages 132–138 287 23. C. S. Draper, E

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for Apollo Guidance, Navigation, and Control at MIT Instrumentation Laboratory.’’ Unpublished manuscript, July 28, 1963. MIT Museum. Also see Hall, ‘‘General Design Characteristics of the Apollo Guidance Computer,’’ section III. 24. Holley et al. ‘‘Apollo Experience Report,’’ 33. 25. Speer, ‘‘Strict Control Kept Out Semiconductor Flaws,’’ 29. 26. Hall, ‘‘Case History of the

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Apollo Guidance Computer,’’ 26. On issuing blank drawings, see Kupfer interview with Ertel. 27. Hall, ‘‘From the Farm to Pioneering with Digital Computers,’’ 28. 28. Hall, ‘‘MIT’s

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, HRST1. 54. Littleton, ‘‘Apollo Experience Report—Guidance and Control Systems.’’ 55. Shea memo to Trageser, November 30, 1964, UHCL Chrono 64-64. 56. Scott, ‘‘The Apollo Guidance Computer,’’ 57. Frasier, HRST1. 58. David Hoag interview by NASA historian, May 15, 1967 (not transcribed), MSC oral histories, audio at NASA UHCL. 59. Martin and

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, HRST2. 21. Martin and Battin, ‘‘Computer Controlled Steering of the Apollo Spacecraft,’’ 400–406. 22. E. M. Copps, Jr., ‘‘Recovery from Transient Failures of the Apollo Guidance Computer’’; Eyles, ‘‘Tales from the Lunar Module Guidance Computer,’’ 9. 23. Copps, HRST4. 24. Martin, HRST2. 25. Johnson and Giller, ‘‘MIT’s Role in Project Apollo

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Operation.’’ 61. Alonso, HRST1. 62. Nevins interview with Mindell, 11. 63. Hoag, ‘‘History of Apollo On-Board Guidance, Navigation, and Control,’’ 281. 64. Scott, ‘‘The Apollo Guidance Computer, A User’s View.’’ 65. Nevins, Woodin, and Metzinger, ‘‘Man-Machine Simulations for the Apollo Navigation, Guidance, and Control System.’’ 66. Nevins to Distribution, ‘‘The

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.’’ 15. Manningham, ‘‘The Cockpit.’’ 16. Bush, ‘‘Remarks on U.S. Space Policy.’’ 17. Pyne, ‘‘Seeking Newer Worlds: An Historical Context for Space Exploration.’’ Glossary AGC Apollo guidance computer: main digital computer guiding the CSM AGS Abort guidance system backup digital computer for lunar landings AOS Acquisition of signal: the moment the LM reappears

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interviews conducted under the History of Recent Science and Technology (HRST) project on the World Wide Web are referenced in the text as follows: HRST1 (Apollo Guidance Computer) Ramon Alonso, Dan Lickly, Joe Gavin, David Hoag, Cline Frasier, Eldon Hall, Margaret Hamilton, Fred Martin, group oral history interview by David Mindell, Alexander F

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Division of Expert Labor. Chicago: University of Chicago Press, 1988. Abernathy, William J., and Bruce A. Wilburn. ‘‘Technical Control in the Development Program for the Apollo Guidance Computer.’’ Harvard Business School, Cambridge, Mass. (May 15, 1964): 13. 312 Bibliography Abzug, Malcolm J., and E. Eugene Larrabee. Airplane Stability and Control: A History of

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a Space Shuttle Crew. New Series in NASA History. Baltimore: Johns Hopkins University Press, 1987. Copps Jr., Edward M. ‘‘Recovery from Transient Failures of the Apollo Guidance Computer.’’ Cambridge, Mass.: MIT Instrumentation Laboratory, 1968. Corn, Joseph J. The Winged Gospel: America’s Romance with Aviation, 1900–1950. New York: Oxford University Press, 1983

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Computers: An Autobiography.’’ IEEE Annals of the History of Computing (April–June 2000): 28. Hall, Eldon C. Journey to the Moon: The History of the Apollo Guidance Computer. Reston, Va: American Institute of Aeronautics and Astronautics, 1996. Hall, Eldon C. ‘‘MIT’s Role in Project Apollo, Vol. III: Computer Subsystem.’’ R-700. Cambridge

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, Mass.: MIT Instrumentation Laboratory, August 1972. Hall, Eldon C. ‘‘Reliability History of the Apollo Guidance Computer.’’ CR-140340. Cambridge, Mass.: Charles Stark Draper Laboratory, 1972. Bibliography 321 Hall, Eldon C. ‘‘Case History of the Apollo Guidance Computer.’’ E-1970. Cambridge, Mass.: MIT Instrumentation Laboratory, 1966. Hall, Eldon C. ‘‘A Case History of the

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AGC Integrated Logic Circuits.’’ E-1880. Cambridge, Mass.: MIT Instrumentation Laboratory, December 1965. Hall, Eldon C. ‘‘General Design Characteristics of the Apollo Guidance Computer.’’ R-410. Cambridge, Mass.: MIT Instrumentation Laboratory, May 1963. Hall, Eldon C. ‘‘Computer Displays.’’ E-1105. Cambridge, Mass.: MIT Instrumentation Laboratory, January 1962. Hall, Eldon

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Control, Guidance, and Navigation.’’ Cambridge, Mass.: Charles Stark Draper Laboratories, 1970. Hopkins Jr., Albert L., Ramon Alonso, and Hugh Blair-Smith. ‘‘Logical Description for the Apollo Guidance Computer (AGC4).’’ Cambridge, Mass.: MIT Instrumentation Laboratory, 1963. Horner, Richard. ‘‘Banquet Address before the first Annual Awards Banquet of the Society of Experimental Test Pilots.’’ SETP

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All Mine.’’ Life 26 (October 1962): 39. Schirra, Wally, and Richard N. Billings. Schirra’s Space. Annapolis, Md.: Naval Institute Press, 1995. Scott, David. ‘‘The Apollo Guidance Computer: A User’s View.’’ Lecture at the Computer Museum, Boston, Mass., June 10, 1982. Computer Museum Report 2 (Fall 1982). Transcript of Scott remarks courtesy

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, 110, 127, 134, 137 SR-71, 45 Adams, Mike, 59–61 Adaptive control systems, 57–61, 77 stability and, 19–22 U-2, 45 AGC (Apollo guidance computer), 259 X-1, 44, 46 Apollo 4 and, 174–175 X-15, 6 (see also X-15) Apollo 5 and, 175 Air-pressure gauges, 24

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, 108–109 Laning and, 99–102 Compasses, 24 MAC project and, 148 Computers, 15 mainframe, 148 AGC, 126–128, 133, 137, 143 (see also AGC [Apollo guidance computer]) Alonso and, 100, 102 Mars probe and, 99–101, 154 mean time between failure (MTBF) of, 130, 133 340 Computers (cont.) memory issues and, 152

Shoot for the Moon: The Space Race and the Extraordinary Voyage of Apollo 11

by James Donovan · 12 Mar 2019

it. Upon arriving there, he was given a choice: he could work with the big Mission Control Center ground computers or the onboard software, the Apollo Guidance Computer (AGC). He chose the one that would fly, the AGC, and though he felt intimidated at first, he found that almost no one there knew

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Officers Training School” running through every type of guidance failure conceivable, hundreds of them. There were also trips to the MIT Instrumentation Lab, where the Apollo Guidance Computer had been designed, to go through all the software what-ifs, and to the Griffith Observatory in Los Angeles with astronauts; because they would navigate

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behind the moon, where they’d be unable to communicate with Mission Control if a problem occurred. The burn would be handled by the onboard Apollo Guidance Computer. After checking their numbers several times, they would have to enter the directions and figures manually. One wrong digit could mean a catastrophic change to

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unprecedented solitude. He only wished he could sight the LM whenever he passed over it. Knowing where Eagle was would supply valuable information to the Apollo Guidance Computer to calculate rendezvous maneuvers for the next day. He continued to listen in as the Eagle’s crew described the sights around them while preparing

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, and various connections; one less-than-perfect joining could mean a quick death. Their heavy-duty spacesuits were twenty-one layers thick and, like the Apollo Guidance Computer, had been fabricated using the “little old lady” method. Each suit would be pressurized to 3.5 pounds per square inch, making it bulky and

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took until July to be able to run it. The final sim was always normal—no aborts.” Finally, Richard H. Battin, who helped create the Apollo Guidance Computer at MIT, said in his April 4, 2000, interview for the JSC Oral History Project, referring to the 1201/1202: “Fortunately, they had already experienced

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; Gallentine, Infinity Beckoned, 53–60. not considered essential: Life, September 5, 1964; Mindell, Digital Apollo, 123, 294. See also Frank O’Brien’s superlative The Apollo Guidance Computer. Sixteen: Descent to Luna “The unknowns were rampant”: Hansen, First Man, 529. “I’ve never seen”: Quoted in Harland, The First Men on the Moon

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. Promised the Moon. New York: Thunder’s Mouth, 2002. Oberg, James E. Red Star in Orbit. New York: Random House, 1981. O’Brien, Frank. The Apollo Guidance Computer: Architecture and Operation. Chichester, UK: Springer-Praxis, 2010. O’Leary, Brian. The Making of an Ex-Astronaut. Boston: Houghton Mifflin, 1970. Ordway, Frederick I., III

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) was a computer whiz kid, only twenty-four during Apollo 11. Though it had the equivalent of only 72 kilobytes of memory, the rope-wired Apollo guidance computer was extremely reliable. Jack Garman’s cheat sheet, which he consulted to make sure the 1201 and 1202 alarms would not impede the landing. (Courtesy

Moonshot: The Inside Story of Mankind's Greatest Adventure

by Dan Parry · 22 Jun 2009 · 370pp · 100,856 words

Moon. 25 NASA's Lunar Surface Journal, at http://www.hq.nasa.gov/alsj/a11/a11.1201-fm.html; and http://en.wikipedia.org/wiki/Apollo_Guidance_Computer 26 Armstrong, Aldrin, Collins, op. cit.; and Collins, op. cit. 27 http://www.nasm.si.edu/exhibitions/attm/a11.jo.fc.1.html 28 Aldrin

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www.lbjlib.utexas.edu/johnson/archives.hom/speeches.hom/670127.asp www.hq.nasa.gov/alsj/a11/a11.1201-fm.html en.wikipedia.org/wiki/Apollo_Guidance_Computer www.nasm.si.edu/exhibitions/attm/a11.jo.fc.1.html www.thespacereview.com/article/188/3 www.thespacereview.com/article/735/1 www.pbs

Our Robots, Ourselves: Robotics and the Myths of Autonomy

by David A. Mindell · 12 Oct 2015 · 265pp · 74,807 words

landing. Armstrong’s right hand is reaching up to turn off the automatic targeting and autoland features to land in a semimanual mode. Note the Apollo Guidance Computer on the lower right, which could indicate an angle for Armstrong to look through the passive HUD inscribed as a reticle on the window. (IMAGE

Never Panic Early: An Apollo 13 Astronaut's Journey

by Fred Haise and Bill Moore · 4 Apr 2022 · 263pp · 72,899 words

a formal procedure with rigid command and response. The action was slow-moving, and Buzz would pass the time working on the DSKY, or the Apollo Guidance computer’s display keyboard. On one occasion, Buzz succeeded in freezing up the DSKY—something that was never supposed to happen. Draper Lab came up with

Into the Black: The Extraordinary Untold Story of the First Flight of the Space Shuttle Columbia and the Astronauts Who Flew Her

by Rowland White and Richard Truly · 18 Apr 2016 · 570pp · 151,609 words

backup systems, the safety of the spacecraft depended on the reliability of the single computer. With so much at stake, a tailor-made computer—the Apollo Guidance Computer—was created by MIT in which the possibility of failure was simply designed out. Each component of the new processor was tested at every point

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17, 80, 81, 121, 153, 157, 260 Apollo 19, 80 Apollo program, 84, 92, 143, 369 abort procedures, 201–2 Apollo command module, 48, 99 Apollo Guidance Computer, 109 astronauts, 42, 164 capsule design and construction, 105–6, 121, 155 capsule reentry, 50 future of, 56, 66 heat shield design, 48, 132, 134

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–83 STS-107, 393 temperature control, 275–76 Columbia (ship), 210 command modules, 246 Odyssey, 76, 77, 94 computer systems, 108–9, 154, 156, 186 Apollo Guidance Computer, 109 IBM 305 RAMAC, 108 IBM 4pi, 32, 108–9, 110, 129 IBM AP-101, 129, 130–31, 228 MOL program, 42 PASS (primary avionics

Boom: Bubbles and the End of Stagnation

by Byrne Hobart and Tobias Huber · 29 Oct 2024 · 292pp · 106,826 words

better chips to meet that demand for computation, which encouraged the next generation of chip manufacturers to build still-faster chips, and so on. The Apollo guidance computer possessed a 1 MHz processor; a typical smartwatch today possesses more than 1,000 times that processing power. In other words, Apollo spawned Moore’s

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which a vacuum tube cannot do.” 212 This descriptor is in the running for understatement of the century. The transistor would end up operating the Apollo guidance computer, calculating pi to 31 trillion digits, and defeating the best human player at chess (1997), Rubik’s Cube (2011), and Go (2016), to say nothing

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the upstart company might go out of business before then, NASA provided contracts for ground test equipment, ensuring Fairchild would have a reliable customer. The Apollo guidance computer was the first major test case for the new computing paradigm. As a single-use product, there was no margin for error. In some respects

Chasing the Moon: The People, the Politics, and the Promise That Launched America Into the Space Age

by Robert Stone and Alan Andres · 3 Jun 2019

be as small as a wristwatch, would allow anyone anywhere to access the world’s great libraries. The integrated circuit that was used on the Apollo guidance computer a decade earlier had since been superseded by faster and vastly more sophisticated chips. In the United States the first personal computers were being sold

The Innovators: How a Group of Inventors, Hackers, Geniuses and Geeks Created the Digital Revolution

by Walter Isaacson · 6 Oct 2014 · 720pp · 197,129 words

could fit into a nose cone. So it was designed from scratch to use the most powerful microchips that could be made. The seventy-five Apollo Guidance Computers that were built ended up containing five thousand microchips apiece, all identical, and Fairchild landed the contract to supply them. The program beat Kennedy’s

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. These massive and predictable sources of demand from the government caused the price of each microchip to fall rapidly. The first prototype chip for the Apollo Guidance Computer cost $1,000. By the time they were being put into regular production, each cost $20. The average price for each microchip in the Minuteman