My goal in transit is never to be seen. No fighting airplanes. No looking at airplanes except on radar. No attacking lone destroyers (unless I'm really busy trying to shorten my life like last time!
).
My goal on approach is to be detected first by the explosions caused when a nice spread of torpedoes hits the largest merchant available.
THEN it's showtime.
I'm a chicken when there's no upside. I'll risk my life for a big payoff only. I made a deal with my crew that we don't commence any attack where we don't have a 50% chance of survival. (Don't tell them, but I have to estimate 75% before I commit to an attack. Dead sailors can't win wars. You're sworn to secrecy.)