I was on BFBC2 as recon, and a Blackhawk was flying towards me, so I shoot my shiny M95 and it hits the pilot square in the head, the plane drops and everyone on it gets out. (3-4 People)
I take them all out with my pistol and turn around to find a group running towards me, I take out my C4, rig the Blackhawk and I disappear. They all get in it and...
3... 2... 1... Boom.
Another good one is where a Blackhawk was again in the air, I aim for the pilot but get the guy in gunner. In my opinion, I think that is harder than getting the pilot, even though I didn't take the Blackhawk down.