[Crannogman]

That is weird. Make sure the AA crew are the best available - you should be able to get efficiency up near 100%. Man battle stations, and wait until the guns are actually manned to press the "fire at will" button. You don't need to press other buttons, and make sure they are lit before the planes get close.

If you are attacked by planes while surfaced, do man the AA guns and then set them to "fire at will." I generally go to full or flank speed as the plane approaches, and turn so that the plane is approaching from aside and a little bit behind. As the plane is diving, perhaps firing, I put the rudder over hard in the direction of the plane. The bombs generally miss on the far side. The only time I was hit was when I got in the path of 20 torpedo bombers, but none of them survived (most of them crashed into each other).