Cool, it illustrates perfectly what you said
If we could get to remove the text that gives away target identification, course and speed as well as the icons we would have a real hardcore torpedo shooting game
The text is surely located in coordinates in some text file, while the icons are easily made transparent and voilą!
Sadly there is no chronometer in the game
for speed calculation, so you need to it all by hand with your wristwatch. Oh well....
As for Chock's speeds table, it is a great replacement, but for torpedo shooting what is needed is a defletion angle table, which is quite easy to do. I will post one here in some minutes, after consulting the game's torpedo speeds