While raiding a dutch port, on a clear, moonless night, we ran afoul of an asw trawler. After a lucky DC attack, everything topside was destroyed, both diesels, both batteries, hydrophones, etc. We're completely blind.
After barely getting a handle on the flooding, we go silent for 3 hours.
We surface, decks awash. Imagine my surprise to see the trawler less than 50 meters on our port side, completely dark.
I assume I could have sat there until sunrise.