JudasSheeple Yeah, if I remember correctly they added it during the Naval Strike DLC in BF4. It was called the AA Mine.
Basically it was like a small missile launcher with a sensor, and if a helicopter flew too low within its detection range, it would fire a guided missile at it automatically.
The concept was honestly pretty cool, and from what I remember it was fairly well balanced too. It mainly punished helicopters flying too aggressively at very low altitude without completely shutting air vehicles down.