Aircraft weapons

[thatguy96]

kevineduguay1 said:
Again I ask, why mount the huge GAU-8 whan a much smaller weapon could do the same job? If it did not have a distinct advantage why not just use a 20mm Vulcan?

I would think that the sheer fact that 30x173mm has almost identical muzzle velocity and is bigger and therefore packs a greater punch is a distinct advantage. I do not have any sort of any comparative data, but I wonder what kind of armor penetration most aircraft cannon get.