Gunners Grand Slam Ability Achievement

anyone care to explain how i would be able to get this achievement? ive been trying for a while now and i haven no luck =/ thank you

Use your flying ability to hover over an enemy then press x. Works great at the top of lifts because you know exactly where they will land and lots of classes like the assault want to try and charge you up there.

Be sure that you do not drop from a ledge. I didn't get it until I actually jumped up and hovered.

It's easiest to get it on unaware snipers. That's how I got mine, at least.