Aerial Refueling

Aerial refueling, also called Air refueling or in-flight refueling (IFR) or air-to-air refueling (AAR) or (in the UK) tanking. Note that AAR also stands for "After Action Review" (de-briefing) and in aviation, IFR also stands for "Instrument Flight Rules" (flight by instrument references only such as in cloud ).
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A procedure used by the military to transfer fuel from one aircraft to another during flight. (FAA4)

A procedure used by the military to transfer fuel from one aircraft to another during flight.
(Refer to VFR/IFR Wall Planning Charts.)