Threshold
Data
Where this data comes from
And, just as importantly, what it is not.
Not for navigation. Threshold is a pre-flight situational awareness tool. It is not a certified electronic flight bag, not an approved source of aeronautical information, and not a substitute for an official preflight briefing. Verify everything against official sources before flight. Charts, airport data and navaid data in this application may be out of date relative to the current publication cycle.
Federal Aviation Administration
Aeronautical charts (VFR sectional, IFR enroute low and high), terminal procedures, airport and navaid records, airspace boundaries, special use airspace, and NOTAMs are sourced from the U.S. Department of Transportation, Federal Aviation Administration, Aeronautical Information Services.
Threshold acknowledges the FAA as the source of this data. Threshold is not endorsed, approved, or authorized by the Federal Aviation Administration. No FAA seal, initials or other insignia is used in this application or on this site.
Special use airspace locations, boundaries and restrictions may change at any time. Refer to NOTAMs for current information.
Airport records for facilities outside the United States are limited, are not guaranteed to be complete, and should not be considered an official source. Consult the appropriate national authority.
National Weather Service
METARs, TAFs, AIRMETs, SIGMETs, pilot reports and winds and temperatures aloft are sourced from the NOAA / National Weather Service Aviation Weather Center.
Radar imagery
NEXRAD base reflectivity mosaics are produced by the Iowa Environmental Mesonet at Iowa State University, from NEXRAD Level III products distributed by the National Weather Service. The mosaic is generated by an automated process; errors can occur, and the imagery is provided without warranty.
Magnetic variation
Magnetic declination is computed from the World Magnetic Model 2025, produced jointly by the NOAA National Centers for Environmental Information and the British Geological Survey on behalf of the U.S. National Geospatial-Intelligence Agency and the U.K. Defence Geographic Centre.
Copyright status
This application incorporates material produced by agencies of the United States Government, including the Federal Aviation Administration and the National Oceanic and Atmospheric Administration. That material is not subject to copyright protection in the United States. Copyright in the application itself, including its software, presentation and original text, is retained by Pollard Labs LLC.
Reporting an error
If you find an error in charted or published aeronautical data, report it to the FAA through its Aeronautical Chart Safety Alerts and Notices page, which also lists errors already identified. Issues specific to this application can be sent through the contact page.