Plain English Meaning
A reference book (now called the Chart Supplement) that tells pilots everything practical about an airport — its runways, frequencies, fuel, lighting, and any special notes — so they can plan a safe arrival or departure.
Full Definition
A former FAA publication that listed detailed operational information for airports, heliports, and seaplane bases in the United States, including runway data, radio frequencies, services available, airspace, and remarks. The A/FD was reorganized and renamed the . in 2016, but the term A/FD remains in widespread use in older training materials and conversation.