Cueing counter-drone defences from hostile-fire indicators

Could a hostile-fire indicator passively detect and cue defences against FPV drones?

Yes. It resembles established passive cueing methods that detect an incoming weapon and trigger a defensive response.

The proposed adaptation is an established sensing concept applied to a new threat. Forces have long used passive systems that wait for an incoming weapon or its seeker signature to cue a defensive response. Reactive armour is a simple analogy because the attack activates it rather than requiring continuous aim. Against FPV drones, a hostile-fire indication could provide warning and targeting information for a countermeasure.