Let me correct my colleague : every AA are repellent, with veterancy they gain in killing power but that's never their intended role so a fighter with some AA to protect its fall back is always a better investment.
If you still want to kill planes with AA take it with veterancy if possible, put a leader nearby to increase veterancy even more, place them near a juicy target and wait for a plan to attack it. The plane should not come back home.
Number of shots and distance are the major factor in air lethality so flak vierling and tri polsen at short range are the most lethal AA weapon.
Veterancy also increase planes dodging power so don't expect to shoot down an elite fighter any time soon.
[DAY]Topspin2005 wrote:The discuss should also be about what AA should be ... if it should block/stunn planes, it has to stunn them faster! Because actually even with 400 points AA you mostly don't stop a plane before it drops the bombs or fire the rockets.
That shouldn't happen, 2x75pts 37mm repel any fighter-bomber targeting their position. Heavy bomber are more difficult to fend off but they cost much more so they are juicy targets for fighters.
One possible explanation would be that you have put your AA behind hedgerows where their line of sight is obstructed.