Did you know that an B-25 bomber crashed in the Mon River in Pittsburgh in 1956, never to be found again? All six crew members survived the crash but 2 died as a result of exposure in the water. Soldiers descended on the site and suspiciously closed all access to the accident site.
That's just crazy. Here's an official report if you want to read about it. A more interesting account seething with speculation and mystery can be found here.
Apparently if you grew up in these parts, you know all about it but it was news to me (56 years later)
Also there's a field trip in our future but it involves a yarn store rather than any underwater searches. Maybe we can go looking for the plane next time.