When I'm being attacked by AC I place my Flack gunners (PO's) up and my Deck gunners (PO's) up and then man the DG myself. This is the only time I man the DG myself BTW. I let the Fack Gunner's take care of the AC from abeam to astern and I shoot down AC from abeam to Ahead. Its all in the timing with the DG as u only get roughly a 45° elevation so U have to wait till the AC is heading away and quite a ways out. Lead just enough and BOOM, 1 dead plane via DG. Best used on the Big ol slow bombers like the B4, Sunderland and Welly.
To many hours spent using DG's on Naval units in games leads to using them for every thing.
