That is not hard to do.
If you want the unit to delete itself when he reaches the waypoint...
Put this in waypoint on activation for the waypoint:
:-*deletevehicle 'nameofplane'
Note this...
The pilot(s) will eject after the unit deletes itself. If the plane deletes itself over water, the pilots will die.
If you want to delete the pilot(s)
'planename'D this deletes the driver of the plane, the name of the plane with a cap D in front of it, this goes for gunner, and there are titles for commander, probabley C