Does exist, as demonstrated by the reduction of helicopter attrition in Iraq.
American troops in Iraq figured out how Iraqi terrorists had managed to ambush American helicopters with heavy machine-guns and get away with it.
The Iraqis had used trucks with the machine-gun mounted in the back, and a tarp over metal supports (a common feature of military trucks) to conceal the weapon.
The tarp was rigged so it could be quickly pulled aside, as well as the metal supports for the tarp. This enabled the heavy machine-gun to immediately open fire.
There were four of these trucks, and they roamed around areas that American helicopters were operating above.
But then the terrorists’ luck ran out:
One of these trucks was spotted, with its machine-gun revealed, by a UAV, after informants indicated that this was probably the weapon responsible. U.S. intelligence then analyzed video and other data they had, and put more UAVs over areas believed frequented by the trucks.
On the ground, intelligence operatives began beating the bushes for information on these mobile flak traps.
Soon the four trucks were identified and, one by one, destroyed with smart bombs.