It was because of that real-life incident in U-571, all of the US Navy had to carry a German dictionary and travel guide on all ships, because of the "Keitel Incident."
So when the Navy captured the U-505, they were prepared.
Boarding crew: "The text, it's all in German still!

"
Crewman #2: "Fetch the dictionary!"
Crewman #1: Guten Tag. Wieviel kostet ein Bier?