..to flak or not to flak....

Originally Posted by 3Jane

I think it's a game bug which causes one or more of the flak guns not to fire. As I remember it, with multiple flak positions you have to manually 'visit' each position to make them all work.
As for actually using them, only if the water is too shallow to dive or some other reason why you can't dive. Also, if the aircraft isn't spotted until it is fairly close. By that time there won't be enough time to dive fully before it attacks.

3Jane is right: the way to positively assure all the flak stations fire is to toggle between each one and the bridge. Hit F4, then the first flak station, then F4 again and the next flak station, etc, until you've gone to each one. That should do the trick!