They exist irl, and there are 2 types of them:
US Ford Siam, which is simply an independent stinger (Siam literally means Self Initiated Anti-Aircraft Missile)
https://ru.wikipedia.org/wiki/Ford_SIAM
#Anti Helicopter Mines
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And Russian PVMs, which are literally mines
I think that in order to prevent this from becoming just an instant kill device, you could make them very easy to detect, while also adding a detection system in the game like in Wargame, where you can hide almost literally in front in your enemy, but as soon as you fire a single shot, any optics will immediately detect you from very big distances