[Heibges]

I agree with Kapt and Pen. The only way I have found to get "realistic" results is use SOP from the Uboat Commanders Handbook.

Basically it is three rules.

1. Only use hydrophones at dawn, dusk, and in terrible visibility.
2. Torpedo Allocation. Fan shooting at all targets.
3. Maximum range for deckgun is 1100m.

After studying the Uboat Commanders Handbook, and other sources, I developed these SOP's and I get careers that could straight off from uboat.net.

1. 1/3 of my patrols I see no targets.
2. 7 ships is about the most you will ever sink in a Type VII on one patrol.
3. A career of 13 Patrols will yield about 150K tons on average.

Certainly I still make the Most Successful list, but am much more in line with historical averages.