try h.sie's Realistic Repair and Flooding Times Mod.
It makes the Persicope useless above 4 knots and many other nice things.
http://www.subsim.com/radioroom/showthread.php?t=174225
btw. can anyone provide me with screenshots or the discussion thread for hitmans optics?
Cant find it in the mod section, want to take a look at it before i install it.