You're right siegecrossbow, that did happen. But with the spread of look-down shoot-down capability amongst fighter jets, that sort of a shot (which is already extremely lucky) would be almost impossible to do again. In truth, the fighter should win every time.
Speaking of crazy kills made from helicopters, in the Vietnam War, a CIA base (Lima Site 85, later overrun by the communists in a famous battle) in Laos was bombed by 3 Pathet Lao An-2 biplanes. An American Huey helicopter with a CIA crew took off to chase them away and one of the biplanes was shot down by the only armament the Huey had: a guy shooting an AK-47 out of the door!
ROFL that was pure ownage. only in movies, and that was hilarious. let's not forget helicopters only stand a chance earlier on when technology gap isn't as big, so they stand a very minor chance. also the example mccool gave was when back when technology wasn't that big of a factor, and in fact, bending on the american's favor. we can almost say that the huey was more high-tech than the biplane, therefore something like that happens.
these days..well we all know how sophisticated fighters are (with stuff such as gen5 planes and their AESA and toys...), as well as all the advantages they have in performance, especially speed. helo only beats fighters on the battlefield where sustained periods of close infantry and battlefield supports were needed, and the ability to hover, hide, low speed manuverability etc.
in contrast to mccool's examples of helo killing fighter, in the gulf war, a f-15 made the most unorthodox AA kill against a chopper. the f-15 spotted a hovering helo, and then by targetting the helo, it dropped a smart bomb on it and killed it lol