I've noticed that the lightboard (commonly called the 'Christmas Tree') onboard all the subs in SH4 show all hatches and vents either ALL OPEN (surfaced/RED) or ALL CLOSED (submerged/GREEN).
My beef is that during surface operations, ALL hatches would never be left open when operating in wartime conditions (i.e. enemy waters). MOST would be closed with the exceptions being the bridge hatch and the main induction vents.
All exterior penetrations have an indicator light on the Christmas Tree. These would include the Torpedo Loading Hatches, which would be opened ONLY when in port and loading new torpedoes. These two hatches should always have a green indicator light glowing.
Access doors/hatches in the sides of the conning tower (that allow access to deck and AA guns) would be opened to allow the battle stations-surfaced gun crews access to their guns would be opened (red indicator), then closed again by the last man out the door to prevent heavy seas from flooding the sub (green indicator).
A minor beef, I'm sure. Comments?