Finally I came across that ship...
And indeed it got away. So fast, I couldn't catch up! Not even with "wahnsinnige fahrt"! But you also wrote "If they detect you then they will take evasive action". So what do I learn from this statement? Simple, make sure they don't detect you! Right?
But you can be sure that as soon as I get the message "Ship in sight, long range" they've seen me too. Does that mean I have to constantly sail at periscope depth? Search the entire area with a diameter of 70 kilometers?
Interesting question!
Or is this the difference between reality and playing a game?
How do you handle this?