US Airspace Files from NFD

Frequently Asked Questions

Q: I am a reseller. If I subscribe to your service, can I bundle and distribute the files I download with my product to my customers?

A: Unfortunately, the notification agreement I have with the FAA prevents me from allowing this. When I receive an error alert or update notice from the FAA between the 28-day update cycles, I am required to immediately notify my customers of the update, and I can't do that if I have to go through a third party. However, I will continue to monitor the FAA's policy for a better way around this.

Q: Is my subscription automatically renewed after one year?

A: No. But we will e-mail you a reminder, of course.

Q: Is there any limit to the number of times I can download airspace files?

A: No.

Q: Can you send me updated airspace files automatically, e.g. if a new NDF release creates a change in my airspace file(s)?

A: I'm looking at how to do this. Until then, check for announcements on the home page; I'll post the date each time the FAA updates the NFD, which is every 28 days.

Q: Can I give copies of my files to friends or members of my club?

A: I have no strict licensing or distribution policies for the airspace files you download here. However, I need enough honest customers to be able to convince the FAA that all of my data's users will receive notice when the FAA has an alert or correction to distribute. (My account with them is a privilege, and if they revoke it, this web site will go away.)

Q: Why don't you support Canada and/or Mexico?

A: Only United States airspace is included in the NFD.

Q: What do I do with the .kml file?

A: Whatever you want. If you use Google Earth™, you can open the file therewith and browse your airspace in 3D. This is a handy way to check for errors, omissions, and completeness before using the other file(s) in your navigation software.

Q: Can my desired region be the USA? Or do I have download a bunch of smaller areas?

A: Your desired region can be as big as you want. To get everything, specify top = 60, left = -170, bottom = 0, right = -60. (Just don't open the .kml file with Google Earth -- it will be too big.)

Q: I don't see some of the restrictive areas in SeeYou. Wassup?

A: SeeYou does not seem to treat the Tim Newport-Peace TYPE=xxx values in accordance with the TNP/SUA standard. In SeeYou, visit Tools | Airspace and make sure 'Other' is checked. (You may need to do the equivalent routine in SeeYou Mobile.)

Q: How do I create airspace files to use with SeeYou Mobile?

A: Load your airspace file(s) in SeeYou and run the Mobile Wizard. (Your PDA must be connected with ActiveSync, of course.)

Q: How are airport turnpoints created from NASR? (And what is NASR?)

A: NASR is the FAA's National Airspace System Resources database. The NASR contains airspace like the NFD, but not with the same level of precision, and (according to the FAA) "not for navigation purposes". The NASR does, however, contain airport data not found in the NFD that is useful for creating turnpoints to use in conjunction with soaring turnpoint databases.

While this site will produce both Cambridge and SeeYou format turnpoint/airport lists, JustSoar recommends using the SeeYou format as a starting point. This format contains several fields not found in the Cambridge format, including communications frequency, runway direction, and runway length, and SeeYou allows you to export the file into just about any other format.

Q: How does JustSoar build the text fields of the SeeYou turnpoint output?

  • The name field is from the airport name field of the NASR database, recasified from UPPERCASE to Camel Case.
  • The code field is constructed from the first eight letters of the (original) name. If the shortened name has already been used, it is then taken from the first six letters of the name, followed by the two-letter state abbreviation. If this is still not unique, the first four letters of the name are used, followed by the state, followed by a serial number, e.g. the code for "FLYING FOOBAR RANCH" in Texas (which has dozens of flying ranches) might become FLYITX12.
  • The frequency field is assigned the airport's CTAF frequency, if provided, else the first UNICOM frequency, if provided. (No tower, ATIS, or AWOS frequencies are contained in the NASR.)
  • The description field is constructed as follows:

    [CTAF-freq] [UNICOM-freq(s)] [100LL] [Runway1 ...]

    ... where each RunwayN looks like

    [Designation LxWft Surface]

    Examples:

    "17/35 3906x50ft Asph"
    "C122.8 U122.8 100Ll 02/20 2650x110ft Dirt-G 17/35 5929x60ft Asph-G"
    "C122.7 U122.7 100Ll 05/23 5200x100ft Asph-G"
    "C124.95 U122.95 03/21 4285x75ft Asph-Conc 08/26 12001x150ft Conc-E 12/30 5366x100ft Asph-Conc"

    (The letters after the surface type indicate condition: (E)xcellent, (G)ood, (F)air, (P)oor, fai(L)ed)

  • For multi-runway airports, the airport's widest runway is represented in the direction/length fields. (If there are two or more runways sharing the maximum width, the longest among them is chosen.)