According to
Rotorhub, a U.S. Army OH-58D Kiowa Warrior (presumably operating over Iraq) was hit by a 4 lb AeroVironment Raven mini-UAV, which "bounced off."
Brigadier General William Jacobs, Deputy Commanding General at the US Army Aviation Center, Ft. Rucker, said last year that the “number one threat” to helicopters flying at low level in Iraq was “the potential for a collision with a UAV.”
Heads-up out there...!
I/C