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.
|Product||Reflects Changes From||Reflects Changes To||Release Date|
|April 20, 2020||June 14, 2020||June 16, 2020|
|June 15, 2020||August 09, 2020||August 11, 2020|
|DOF (Next)||August 10, 2020||October 04, 2020||October 06, 2020|
For additional information read DOF ReadMe (PDF)