Via czarnajama:
"...can even be completely automated with on-board software..."
I think that detail is something a lot of people don't fully understand yet. The cheap technology has been around a while now for a fully preprogrammed autonomous drone flight with no inputs from a ground controller. From launch to recovery.
A scenario to relate it to the thread issue - Thanks to GPS a drone could be launched to fly a pre-programmed race track on the final approach or departure ends of a runway waiting for a pax jet to fly near or into it. If a small explosive device (something like a hand grenade) were added to the drone and some proximity alert devices installed (cheaply available from the automotive parts world) then what we got is a poor mans (terrorist) anti-aircraft missile.....
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