I once in a panzer and i saw a low flying B17, I fired at AP round at said b17. The round hit him right on his left wing root.
I was expecting the wing to fall off, but it didn't

So I switched to my pintle gun and proceeded to fill his roof (he was turning at the time) with small holes.
I guess the sound was pissing him off, cos next thing i know his wing flops down and his plane flips over, it was more funny cos I knew the guy.
I've also killed people with smoke shells:D