X-Plane data file definitions

Intersection/fix data (fix.dat) 600 version

Scope
File structure
Changes from previous file versions
Example data and explanation

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Scope

This document describes the file format and codes used in X-Plane's fix.dat file, 600 version.

• This data file format is usable with X-Plane version 6.40 onwards.

• This is the "official" definition of the X-Plane file formats.  If you spot any errors or inconsistencies, then please let me know.  Likewise if you do not think that X-Plane is interpreting these data correctly.

• The fix.dat file defines all intersections (also known as "fixes") in X-Plane.

File structure

The file structure is similar to all other X-Plane data files.

• The first line of each file indicates if the file was generated on a PC (“I” for Intel or IBM) or Macintosh (“A” for Apple). X-Plane uses this code to help deal with the different ways in which PCs and Macs manipulate carriage returns in text files, and big-endian/little-endian issues.
• The second line contains a version number used by X-Plane.  This usually implies the first version of X-Plane that can utilise the file format (eg. "640 version" implies that this file format was first available for use in X-Plane version 6.40).   The version number is followed by my own long copyright message that also includes the sequential build number of the data and my own internal code for the metadata that drives the formatting). This copyright message is very long, and includes a reference to the GNU General Public Licence under which this data is published as modifiable freeware, and also an acknowledgement and a disclaimer for the US Department of Defense NIMA for the DAFIF data. The terms of this license require that this copyright message must be left intact if this file is modified and/or redistributed.
• The very last line of each file is marked by a “99”.

Here is an example of the two header lines, some fixes and the file termination line:

I
600 Version - DAFIF data cycle 200502, build 1922, metadata FixXP600, Copyright © 2005, Robin A. Peel (robin@xsquawkbox.net). This data is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program ("AptNavGNULicence.txt"); if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. This product was developed using DAFIF (the Defense Aeronautical Flight Information File), a product of the US National Imagery and Mapping Agency (NIMA). NIMA requires the following warranty statements: (A) Under 10 U.S.C. 456, no civil action may be brought against the United States on the basis of the content of a navigational aid prepared or disseminated by either the former Defense Mapping Agency (DMA) or the National Imagery and Mapping Agency (NIMA). (B) The DAFIF product is provided "as is," and no warranty, express or implied, including, but not limited to the implied warranties of merchantability and fitness for particular purpose or arising by statute or otherwise in law or from a course of dealing or usage in trade, is made by NIMA as to the accuracy and functioning of the product. (C): Neither NIMA nor its personnel will be liable for any claims, losses, or damages arising from or connected with the use of this product. The user agrees to hold harmless the United States National Imagery and Mapping Agency. The user's sole and exclusive remedy is to stop using the DAFIF product.

37.428522 -097.419194 ACESI
30.113944 -081.873014 ACETI
38.144175 -085.003703 ACETO
36.924947 -121.510847 ACETY
43.213144 -113.083522 ACFIJ
99

Sequencing of data is conceptually unimportant.  But it controls the display of data on X-Plane's menu options.  By default, data is sorted by the fix name.

Changes from previous file versions

• There was no previous file version for fix.dat.

Example data

Here is an example data entry for a fix in fix.dat:

35.162472 -106.646500 WOBIN

The meaning of this data is:

Currently, intersections are displayed on X-Plane's charts as little triangles.  If you zoom in quite close, the intersection name will appear. Fixes are also available on the X-Plane GPS displays and in the Flight Management System (FMS).

Fix names are not unique.  They are usually (but not always) unique within a country.  However, the burgeoning number of GPS approaches that are now being designed require a lot of new fix names, and so duplications will become more common, especially for the quasi-numeric fixes often found at a runway threshold or missed approach point (eg. "RW22" at the missed approach point for KAEG GPS 22 approach).

© Robin Peel, 2005.  Last updated May 19, 2007