The Computer Hack That Saved Apollo 14

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Lorenzo von Matterhorn
Jan 31, 2009
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Talk about extreme pressure to perform in order to create a workaround for an intermittent short in the Apollo Lunar Module abort switch...

Love the accent. Reminds me so much of my time living in Scotland.
Excellent! I completely forgot about the abort switch problem. I guess I am getting old.:eyeroll: Thank you.
They should have stopped using Radio Shack switches on the controls! I had heard the following story, doubted it until just found out is true:

The first men on the Moon had to use a pen to fix a broken switch on their lunar module and return home to Earth, British newspaper the Daily Mirror reported Monday ahead of a new television documentary.Neil Armstrong, the first man on the Moon, and Buzz Aldrin, his fellow astronaut, accidentally snapped off the switch of a circuit breaker, and found they could not take off without it.
Aldrin then jammed a ballpoint pen into the hole where the switch had been, allowing the astronauts' lunar module Eagle to leave the surface of the Moon.
According to the documentary "Apollo 11: The Untold Story", to be aired Monday on Britain's Channel Five television, the US was so eager to beat the Soviet Union to putting a man on the Moon, it launched its historic 1969 mission before it was completely prepared.
Then-president Richard Nixon even prepared an address to the nation announcing the deaths of Armstrong, Aldrin and Michael Collins.
"In looking around at some of the lunar dust on the floor, I discovered something that really didn't belong there -- a broken end of a circuit breaker," Aldrin told Channel Five in excerpts printed in the Daily Mirror.
"In the countdown procedure I used a pen, one of several that we had on board that didn't have metal on the end, and we used that to push the circuit breaker in."
The documentary also shows how the US government ordered NASA to cut links with the astronauts if disaster was imminent, not wanting the world to watch images of American astronauts spinning off into space.
Aldrin revealed how the astronauts believed they saw an unidentified flying object during the flight as well, adding that NASA covered it up for thirty years.
"There was something out there that was close enough to be observed," Aldrin said.


I have done a lot of work in industrial and other control systems, had problems with reliability of chinese parts they like to use, static and EMI interference, and just plain shoddy engineering from folks that should know better. The GM killer keyswitches come to mind. It is not hard to make that stuff reliable, just keep it simple, and use gold contacts where necessary. The dream switch these days would use a magnet and hall effect chip, no hard contacts, will always work if parts are good. Switches, pots, and connectors are the biggest parts that cause failure, other than that crappy tin solder. Lead was best, but it is gone now except for medical and military stuff.