PS I've tried slide ruler - it's amazing but didn't have time to do the maths when in the heart of convoy.
PS2 I use only impact triggers with results like huge tanker wiped with one eel...
good luck
The nice thing is that you only have to do it once: Since all ships in a convoy are on the same course, once you have the data for one, you have it for all. That is, of course, until they start esplodifiying...
