Hi Don

I don't know how appropriate that "someone like you" is, I just take a look at everything I can, then try to figure it out how it works, look for more information if I can find it and that's it.

I find the mast height information to be very inaccurate. After all, if the sea state is anything but 0 to 2, the height of the target, especially relative to your own ship will change so much that the height info is next to useless. If I was a u-boot commander, I'd want to have a method that is the simplest and most reliable in any weather/sea state.

I must say that my understanding of the calculations is a bit weak, even after reading about the stuff and playing sub sims with manual calculation options for years, but simple math would say that the target lenght/bearing/heading/change of bearing would be more imporant than the height, which gives one dimensional variable more to work with. After all, the only 'height' variable you're interested in is the depth of the torpedo, whether you want it to blow up under the ship or collide with the hull. Trying to estimate the distance that way simply gets too complicated.