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I understand Armstrong landed the Eagle manually, and Apollo 13 did a manual burn. Other than emergencies like that, did the Apollo astronauts do much piloting of the spacecraft.

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    $\begingroup$ From Wikipedia about Apollo 12: "Most of the descent was automatic, with manual control assumed by Conrad during the final few hundred feet of descent." Apollo 14 : "Shepard then manually landed the LM closer to its intended target than any of the other five Moon landing missions." Apollo 15 from NASA history : " 104:41:13 Scott: Okay. [Jim is confirming that Dave now has manual control of the spacecraft.]" $\endgroup$ – Uwe Dec 1 '19 at 16:52
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    $\begingroup$ Noting that "manual" needs severe interpretation. There is a "computer" in that control loop". $\endgroup$ – Russell McMahon Dec 2 '19 at 5:38
  • $\begingroup$ To expand on @RussellMcMahon's comment, the closest that Apollo got to manual control was "fly-by-wire" use of the attitude-control thrusters: move the control stick, and the computer will fire a balanced pair of thrusters to create the desired movement. $\endgroup$ – Mark Dec 2 '19 at 21:51
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    $\begingroup$ When the decision to use the attitude-control thrusters is made by a human, and not a computer, that is sufficiently manual for me. $\endgroup$ – Bob516 Dec 2 '19 at 21:59
  • $\begingroup$ @Bob516 As I said " Noting that "manual" needs severe interpretation. " -> what you understand by "manual" is an important part of the question. $\endgroup$ – Russell McMahon Dec 3 '19 at 5:05
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All six successful landings were done manually, with the commander taking the controls at about 500 feet altitude. It was possible for the computer to complete the landing automatically, and Jim Lovell claimed that he was going to attempt that mode on Apollo 13, but all the commanders felt more comfortable in manual control in the final phase of landing.

It's worth noting that there were a number of different "manual" control modes. The one used for the final portion of each landing, control program P66, kept the computer in control of the throttle to maintain a selected descent rate, but letting the commander control the attitude (orientation) of the spacecraft and adjust the descent rate. Digital Apollo is a great source for more information on this, as is MIT's report on the Apollo Lunar Descent Guidance system.

Apart from that, all the maneuvers where multiple spacecraft were operating in close proximity were flown manually:

  • The “transposition, docking, and extraction” maneuver, where the command module turns around to retrieve the LM from the S-IVB third stage was flown by the command module pilot.

  • Prior to landing, the CSM and LM would separate and the LM would turn around slowly to allow the command module pilot to inspect the LM visually. This maneuver on Apollo 11 is shown in this video.

  • After the LM ascended from the lunar surface, the initial part of the rendezvous with the CSM was performed by the LM under computer control, but the final approach and docking was again flown manually by the command module pilot.

  • The re-entry could be flown under computer control or manually; by rolling the command module to control the direction of lift, the trajectory could be flown more steeply or shallowly. I don’t know off the top of my head if the manual option was ever used here, or how often.

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  • $\begingroup$ “kept the computer in control of the throttle to maintain a selected descent rate” How accurate and fast was the landing radar to do this reliably? $\endgroup$ – Michael Dec 2 '19 at 10:53
  • $\begingroup$ The vertical portion of the P66 logic updated once per second. I’m not sure of the accuracy of the landing radar but everything I’ve read about Apollo seems to treat the altitude and velocity figures from the radar, given in feet and FPS, as gospel, so at low altitude the accuracy must have been pretty good. $\endgroup$ – Russell Borogove Dec 2 '19 at 15:13
  • $\begingroup$ I wonder if How did Conrad let Bean drive Apollo 12? Did anyone get in trouble? has at least a partial answer based on some of this? $\endgroup$ – uhoh Dec 9 '19 at 2:00
  • $\begingroup$ I think, if that happened, it must have been during the post-ascent approach and rendezvous, but I haven’t found any firm evidence for it. You would definitely not want to mess around during the landing phase. $\endgroup$ – Russell Borogove Dec 9 '19 at 2:36
  • $\begingroup$ @Michael The specified accuracy of the landing radar for both vertical and horizontal rates was 1.5 ft/sec. citeseerx.ist.psu.edu/viewdoc/… $\endgroup$ – Russell Borogove Jan 15 at 5:39

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