[Paul Riley]

Good point about the periscope check before surfacing,and do a sound check before raising the periscope...just to be safe.Its all good practice for later on.Even get into the habit of checking the skies with the OS before surfacing,again another good drill to get into the habit of.
Not sure if this is modelled in GWX3 but also be wary of using compressed air when enemy vessels are suspected to be in the area,in which case I surface at slow speed with no air.According to the 'the uboat commander's handbook' captains had been known to have been detected simply by using their compressed air to aid in surfacing.I personally DO hope it is simulated in the game,and if it isnt,I still do it anyway hehe