Abraham Wald and the airplane diagram with red bullet holes
cameronmoll.com
cameronmoll.com
But from https://steveblank.com/secret-history/ I learned that what really helped the planes most was not better armor, it was radar countermeasures that kept the Luftwaffe from being able to target the bomber stream. If you have an hour, I highly recommend that talk. And the blog series that goes with it is brilliant.
FWIW, I've never seen either image until today, but am familiar with this example (Abraham Wald's WWII plane research) being used when talking about survivorship bias.