Is SMS Comp A Cheat? And a detection question

[Lanzfeld]

If you do not know the heading of a contact then how can your computer calculate the SMS Comp value? It is a cheat as you can almost tell the heading from this number. And if it goes to -50 I know I'm in the baffles even though heading is not known.

Also.....is 10 ALWAYS the magic number for detection or is there play in that number? Can I be detected at 9? Can I not be detected at 11? You know...the HUMAN factor?

[PL_Harpoon]

I'd like to add a question on enemy towed arrays. In my playthrough I've never seen them show anything other than 0.