Skip to page content

Digital Obstacle File (DOF)

The April 24, 2018 release will be the last 56-day Digital Obstacle File (DOF) to contain data integrity codes at the end of each record. Effective June 19, 2018 the 56-day DOF produced every eight weeks will no longer contain these codes in columns 129-134. There are no other format changes.

Please refer to the published 18-01 DOF Data Check Elimination (PDF) informing users the Federal Aviation Administration has made this change to improve efficiencies, consolidate processes and eliminate redundancies. The compressed dataset with these codes and associated programs chckall and dai_datchk are obsolete. The codes and programs have never been included in the Daily DOF (DDOF) Product.

Please update any programs to reflect the shorter record length and refer to the June 19, 2018 DOF ReadMe (PDF) file for the revised format. If you have any questions, please select the Email General Comments link on the right side of this page.

The Digital Obstacle File (updated every 56 days) describes all known obstacles of interest to aviation users in the United States, with limited coverage of the Pacific, the Caribbean, Canada, and Mexico. The obstacles are assigned unique numerical identifiers; accuracy codes, and listed in order by state.

To download a file, right-click, then select "Save" / "Save As" / "Save Target As" to save the desired file to your computer. If you download a zipped file, use an unzip utility to extract the files. The DOF is a .dat file, so you may use Wordpad or most browsers to access it. If you prefer Notepad, use the Courier font to retain proper column formatting.

NEW - Please note that all normal release dates have recently been changed from Mondays to Tuesdays.

Digital Obstacle Files
Product Reflects Changes From Reflects Changes To Release Date
DOF (Zip) April 23, 2018 June 17, 2018 June 19, 2018
DOF (Zip) June 18, 2018 August 12, 2018 August 14, 2018
DOF (Next) August 13, 2018 October 07, 2018 October 09, 2018

DOF Frequently Asked Questions (FAQs)

For additional information read DOF ReadMe (PDF)

Page last modified:

This page was originally published at: