The spirit (or should I say ghost) of Richard Feynmann lives on.
I'm really, really surprised that the sliver wasn't accounted for during the modification. Aircraft maintenance and fabrication is normally much more focused on accounting for everything that goes in and out of an aircraft. Lost fasteners must be found and so forth.
This is indeed "frightening." Maybe Design News should be highlighting this kind of scary story as we approach Halloween.
What stands out to me is how the crew's attitude changed when Len hit the "gear up" switch. He was right from the beginning, but no one took his concerns seriously until he had a physical demonstration. Then he quickly won everyone to his side.
This should be a lesson to all engineers that "show" is better than "tell."
That's why it's so important to do a complete and thorough preflight, especially after any service. Thankfully I've never found any problem other than compass deviation. From time to time I've mentioned that people should do predrive with automobiles as well. At the very least, check all your tires every time you get in the car, and stomp on the brakes to see if they work.
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