Definition
An FAA publication, issued in regional volumes and updated every 56 days, that provides detailed information about airports, seaplane bases, and heliports in the United States, including runway data, lighting, services, communication frequencies, airspace, and remarks not shown on aeronautical charts.
Plain English
A regularly updated FAA book that lists practical details about every public-use airport in its region — things like runway length, runway surface, available fuel, hours of operation, and radio frequencies.
Context Anchor
Pilots commonly use Chart Supplement U.S. during preflight planning and when checking airport details that are too detailed to fit on a flight chart.
Derivation
Formerly called the Airport/Facility Directory (A/FD). The name was changed to 'Chart Supplement' to reflect that it supplements the information shown on aeronautical charts — adding the operational detail that won't fit on the chart itself.
Why Pilots Care
Accurate runway surface and gradient data affect takeoff and landing distance calculations and aircraft performance decisions.
Intuition Check
Do not read “Supplement” as meaning “optional extra.” In aviation use, Chart Supplement U.S. is a standard planning source for airport details that may directly affect safe operation.
Example Sentence 1
Before the cross-country, she checked the Chart Supplement U.S. to confirm the runway surface and gradient at her destination.
Example Sentence 2
According to the Chart Supplement U.S., the runway has a 0.8 percent downhill gradient from threshold to end.