[Heibges]

I remember we debated this before SH3 came out. I believe the issue wasn't do much that they couldn't compute them, but that in a tactical sense, there wasn't much use for them.

The uboat operated on the surface the vast majority of the time. They needed to move at maximum speed to get into position to attack convoy.

When they dove, they dove deep. The area between PD and 150m is like the area between trenchlines in WWI, or the baseline and the serviceline in tennis: no man's land.

So if when you were forced to dive, you happened to have a thermal layer above you it was a bonus, but not something you would figure into your tactical plan.

EXCEPTION: In his memoirs, Dönitz tells a story about a uboat commander operating off Cape Town or Freetown in one of the areas where convoys formed up. He was operating in relatively shallow water, and used a Thermal Layer to sneak in, attack, and sneak out again.