SAM Effectivness

[Mustang]

By "destroyed", do you mean damaged or shot down? If a plane gets hit by a small warhead like one carried on a MANPAD, it will probably stay in the air, but it's likely to be mission-killed. Same with an attack helo- to kill it in one shot you pretty much have to hit one of the rotors or tail boom (to cut off hydraulic supply to the rear rotors) (or of course the cockpit), and that's rare.