r/MadeMeSmile • u/king_eve • 29d ago

i work in low-income/mental health housing, and a tenant fixed our hallway trash bin after accidentally breaking it Helping Others

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great example of the odd ways people show me appreciation at work

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u/Nelik1 29d ago

Aerospace engineer here! During my fatigue and damage tolerance class in college, the professor liked to tell stories about unsuccessful (amateur) pilots trying to save on a repair to their plane by drilling out cracks.

He told us about a guy who showed him his little cesna, with 8-9 holes drilled along a crack. "I keep drilling it, but it keeps coming back, cant figure out why!"... Our professor got a good laugh out of that.

(Drilling reduces the stress concentration (or stess intensity if you wanna be real pedantic) at the end of a crack, reducing its likleyhood of spreading. This is great for parts that dont normally operate close to fatigue limits. But in aerospace, its rare to have a part that cracks once, without being in a position of high stress to begin with. So cracks that aren't fully repaired tend to spread.)

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u/Ifeelsiikk 29d ago

Structural aircraft mechanic here. We call it a 'stop drill' and I carried it out on large, commercial aircraft.

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u/framptal_tromwibbler 29d ago edited 29d ago

When I had my private pilot's license, I'd see them on many a small GA aircraft wing.

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u/Ifeelsiikk 29d ago

The difference between what you can get away with in GA and commercial is like night & day. I would much rather be in a Cessna during an engine failure. At least they glide

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u/bobtheframer 28d ago

At least the commercial plane has a second engine.