"Bob Martin" wrote:

Of course, I
also seem to recall that the shell basically traces a straight line
from barrel to "effective range", and doesn't need drop factored in.

Eh?... surely you're not saying that the rounds don't drop in
flight?...I hope?...


Well, I know the firing barrel is centered laterally, but I think the gun
itself may be angled down a couple degrees (though still passing through the
center of gravity of the aircraft, so as to not produce any pitching
moment), though probably not more than 2 or 3. This would help with gun
tracking and make strafing runs a little safer.

As far as the "straight line" from the barrel... the muzzle velocity of the
GAU-8/A is such that, although the bullets do drop in flight (to not do so
would either imply lift being generated, or laws of physics being violated),
the drop is considered negligible, and therefore the gunsight is a simple
fixed reticle in the HUD.

For example... at 4000 feet, the bullets will only drop about 10
feet--random dispersion will be greater than that.


But that puts the centre of the dispersion pattern ~ten feet
below the aim point at that range doesn't it?
--

-Gord.