As a former Short Range Air Defense (Forward Area Weapons) Crewman 16R (Vulcan), I can say with absolute certainty that it MIGHT be an MI-24. I always mixed up the -24, -26?? and -28..but they were all potential enemy in those days, so mox nix...

Locked in with the Vulcan system's radar, tho, and with 20MM HE Incentiaries @ 6000 rpm, you might wanna call 'em "Toast". The US Navy uses the same system (they call it Phalanx) as an anti-missile system, and they have shot down incoming artillery rounds with it in tests.

Lumpy