Airport Obstruction Charts (AOC) are 1:12,000-scale graphics (1:18,000-scan for Denver International DEN 9077) showing airport obstruction information, FAR Part 77 surfaces, a representation of objects that penetrate these surfaces, runway, taxiway, and ramp areas, navigational aids, prominent airport buildings, plus a selection of roads and other planimetric detail in the airport vicinity. NGS National Geodetic Survey (NGS) has a list of the digital CAD files that are now available for some Airports in Microstation's design file (DGN) format.

An Aeronautical Data Sheet (ADS) Form 292 is provided at no additional cost with each AOC. This document replaces the Obstruction Data Sheet (ODS), formerly distributed with the AOCs. The ADS includes all aeronautical data the National Geodetic Survey (NGS) acquires and maintains for airports and NAVAIDs under FAA/NGS Interagency Agreements. It contains all data from the ODS plus additional information for runways and NAVAIDS. The ADS is available for all AOCs published after December 1, 1997. AOCs published prior to that date will still include the ODS. For the listing of available AOCs and NOS Product IDs, consult the AOC Dates of Latest Editions

For AOCs published after October 1, 2000, the ADS will only be available through a hyperlink in the AOC DOLE.