Terrain and Obstacles Data (TOD) Team - Digital Obstacle File (DOF)

Digital Obstacle File (DOF)

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 are 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. After downloading, use an unzip utility to extract the files. The DOF is a .dat file, so you may use Wordpad, Internet Explorer, or Mozilla Firefox to access them. You may also use Notepad, but the lack of column formatting is harder to read.

A change cycle's DOF zip file is available the day after the last day of that change cycle:

Product Reflects Changes From Reflects Changes To Release Date
DOF Zip File November 11, 2013 January 5, 2014 January 6, 2014
DOF Zip File January 6, 2014 March 2, 2014 March 4, 2014

Future dates are as follows:

Reflects Changes From Reflects Changes To Release Date
March 3, 2014 April 27, 2014 April 28, 2014
April 28, 2014 June 22, 2014 June 23, 2014
June 23, 2014 August 17, 2014 August 18, 2014
August 18, 2014 October 12, 2014 October 14, 2014
October 13, 2014 December 7, 2014 December 8, 2014
The October 14 Release Date is due to a Monday holiday.

For additional information, please read DOF_README.PDF


Should you discover or encounter an error in any of our products, please check the FAA's Special Notices web page to see if the error has been previously discovered or resolved. If the error is not addressed there, please contact us immediately.

To view PDFs, you will need a copy of the free Adobe Acrobat Reader.

Viewers or converters for Microsoft Word, PowerPoint, or Excel documents can be downloaded from the Microsoft Office Assistance Center.


Digital Obstacle File (DOF)
Daily Digital Obstacle File (DDOF)
Construction Notices
Special Requests
Areas of Responsibility (AORs)
Obstacle Types
Power Lines
Frequently Asked Questions (FAQs)

Last updated: March 4, 2014

Questions about this page? Please contact the webmaster, Len Morse.