AI door gunners using the gattling guns on the ghosthawk miss infantry consistently because they are shooting at a point just below the target's feet.
Enemy infantry can walk out into the open, stand still, pull out a missile launcher, lock on and then fire with a ghost hawk blazing away and take no damage. The degree the door gunners miss by increases dramatically with range.
Also the bullet dispersion on the door guns is almost non-existent, which seems very wrong for "mini-guns".
Get a fully crewed ghost hawk, fly it to a point a few hundred meters from some AI targets and order the gunners to open fire. Even while you are hovering and holding the helicopter steady the AI will consistently shoot the ground in front of infantry targets.
I find them quite deadly or missing the target in a random fashion. Your experience resembles as if the miniguns were incorrectly aligned, but they seem quite ok as well. Could you please eventually try it with different AI skill / difficulty and see at what approx. values the gunners miss too much?
Thanks a lot!