system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:How do weapon systems on planes or helicopters register the hits on target?
gpt
They often don't.  If your target stops appearing on your various sensors (often meaning your eyes), you can consider it dead.  To properly assess the damage from an airstrike often requires either boots on the ground or someone else to fly by (perhaps a satellite, perhaps another plane or drone) and perform combat assessment.  It's only in video games where you destroy a target and immediately know that you've done so, for the most part.

edit: and much the same applies to infantry units or submarines or whatever.  If you spend half an hour shooting at some guys in a house and directing artillery on their position, you aren't going to know for sure that they are dead until you actually go over and enter that house.  That's one of the things that makes combat in urban environments so...er...exciting (read: unpleasant and best avoided if possible).  Or if you fire off a torpedo at a submerged contact, you're going to hear a loud explosion if and when that detonates, but you won't necessarily know what happened:  your passive sonar is overwhelmed by all the noise from the explosion for a while, and it will take time to figure out whether that contact still exists.  It's entirely possible in some contexts that you might never know whether you destroyed it, damaged it and let it get away, or missed it entirely.