Final answer:
The approved method for closing a military flight plan is by notifying the flight service station.
Step-by-step explanation:
The approved method for closing a military flight plan is by notifying the flight service station.
The flight service station is responsible for coordinating and managing flight activities, including opening and closing flight plans.
By notifying the flight service station, the military can ensure that the appropriate authorities are aware of the completion of the flight and can take any necessary actions.