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> Apollo 11 had problems with the LM guidance computer, but was saved by Neil Armstrong's piloting skill.

This is a common misconception but mixes up at least three things.

1) Yes, Eagle was long, but not because of a software bug. The exact reason is unclear and there may have been multiple factors.

2) Yes, there were unexpected computer alarms but these were caused by a hardware bug that manifested because a switch was in an unexpected position. The software handled this appropriately.

Margaret Hamilton said: “To blame the computer for the Apollo 11 problems is like blaming the person who spots a fire and calls the fire department. Actually, the computer was programmed to do more than recognize error conditions. A complete set of recovery programs was incorporated into the software. The software's action, in this case, was to eliminate lower priority tasks and re-establish the more important ones. The computer, rather than almost forcing an abort, prevented an abort. If the computer hadn't recognized this problem and taken recovery action, I doubt if Apollo 11 would have been the successful Moon landing it was.”

3) Neil Armstrong did adjust the landing point late in the descent after noticing rough terrain. He utilized semi-automatic control to do this. Essentially adjusting the target point for the autopilot. Eagle wasn’t directly flown like an aircraft.

https://en.m.wikipedia.org/wiki/Apollo_11

A great video on the AGC and Apollo 11 landing: https://youtu.be/B1J2RMorJXM?si=Ypn6Gtp16_DEkpK9




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