system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Signs on the freeway that say "Speed enforced by aircraft"

What aircraft are these? And how are they enforcing speed?

I assume it's not armed drones decimating speeding minivans.
gpt
It just means that there may be an airplane or helicopter overhead checking your speed.  If you're breaking the limit, a car will be dispatched to pull you over.

That said, it's almost always a bluff.  Enforcing speed limits by aircraft is simply too expensive and not done very much.