trigger maru question ?

[Lt commander lare]

hello i was wondering this is my first campaign playing with triger maru loaded i have always played stock for rsrdc and i was just wondering what does raising the sd mast do in the game while im at periscope depth or is rasing it just for fun or does it actually do something in the game by the way i see why trigger maru was voted best mod great job ducimus


lt commander lare