take control of a Greyhawk and use a trigger to deletevehicle the greyhawk
this will simulate a respawn script activated on the greyhawk when damage is to low and respawn is in progress. while flying or "take control" is used the screen will freeze and the uav terminal doesnt exit properly. the only workaround i know is to reconnect to the server.

not tested on other drones but i guess its all the same