"Tony Williams" wrote in message m...
The ultimate range limitation given current helicopter installations
would be the maximum elevation permitted by the turret. The AH-64's
gun is limited to only 11 degrees (the French THL turret manages up to
30 degrees, the AH-1's M197 20 degrees).

Hmm. Good point. A new helicopter might have different limits, but we'll
be using the existing fleet for a long time.

The ballistic charactistics of the projectiles is also an issue. At
extreme range short aircraft cannon shells like the western 20mm and
30mm may lose stability and start tumbling. The Russian 30mm is much
better; the shells are much heavier and will carry further, but their
mountings don't have the elevation.

I don't know enough to understand this. Is tumbling bad? I understood for
something like a personal rifle it was a good thing in that it maximzed damage.



Then there's the stability of a helicopter as a gun platform. I
suspect that dispersion at long range would be considerable.


Sure. But if it's good enough at 1000 meters to hit a truck, then at 10,000
meters it should hit an area with a diameter of 10 trucks. That's a small
area given enough rounds on target. Of course I'm going beyond my area of
expertise here.



All-in-all, probably a non-starter for any practical purposes.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Discussion forum at: http://forums.delphiforums.com/autogun/messages/