It's not. Choppers are one hit kills with RPGs.
Can only assume you hit it but it didn't register
Their might be something as I got the same and it just flew off.
Also, really annoying how the Scout copters are now, you cant really pick them off, they stay in the air for ages if you are in a copter facing each other back and forth, can go on for ages and has became less about skill.
I still cannot fathom how the IGLAs can lock, track follow and reload faster than any of the Attack choppers etc like they have the most advanced locking system in the world, choppers have in the most part been made next to usless, skill and that can make up for so much, but a lot of the counter measures arnt stopping missles, take a hell of a long time to recharge, and if in the Viper ( which has became a slow lumbering beast for some reason) it just turns on its side and you hit the ground with NO chance of recovery.
Also jets, still far to over powerd, taking out the C-130 in a single strife run etc, it doesnt feel balanced at all, that and the warning system is utterly borked!