CONVENTIONS

UNIVERSAL DATA DELIVERY FORMAT

The following conventions have been adopted for UDDF files:

- UDDF is furnished as ASCII files.

- Each field is delimited by a "pipe" symbol (|).

- The five data sections are separated within a file by an "at" symbol (@). For example, the "Airport" section is separated from the "Runway" section by a "@".

- Data sub-sections within a section are separated by a "pound" symbol (#). For example, runways within the runway section are separated from each other by a "#".

- The end of the file is indicated by an "EOF".

- West longitudes and south latitudes are negative. East longitudes and north latitudes are positive.

- All elevations are in FEET.

Naming conventions for UDDF files follow:

Sample airport file name is "MFR__96A.***" where:

MFR__

Airport location identifier as published in FAA Order 7350.**, "Location Identifiers," as amended. Airport files contain data associated with the indicated airport and located no greater that 10 nautical miles from the Airport Reference Point.

96A

Year (96) of file posting and version (A) within that year. For example, 96A indicates that this file is the first MFR file posted in calendar year 1996. 96B would indicate that this file is the second MFR filed posted in 1996. 97A would indicate that this file is the first MFR file posted in 1997.

.*** = .TXT

Obstruction section contains features representing FAR-77 Obstruction Identification Surfaces (OIS).
Files uploaded prior to July 22, 1998.

.*** = .F77

Obstruction section contains features representing FAR-77 OIS.
Files uploaded after July 22, 1998.

.*** = .ANA

Obstruction section contains features representing ANA (Area Navigation Approach) OIS.

.*** = .CMB

Obstruction section contains features representing a combination of FAR-77 and ANA OIS.

.*** = .LPV

Obstruction section contains features representing ANA-LPV (Localizer Performance With Vertical Guidance) OIS.

.*** = .OEP

Obstruction section contains features representing OEP (Operational Evolution Plan) OIS.

.*** = .CGR

Obstruction section contains features representing CGR (Congressional Airport) OIS.

.*** = .SPC

File contains data that cannot be incorporated into the above mentioned file types due to conflict.

Sample Miscellaneous data file name is "NAV1196.TXT" where:

NAV11

Miscellaneous data file indicator. Miscellaneous data files contain data for navigational aids which are either not associated with an instrument approach procedure for an NGS surveyed airport or which are located more than 10 nautical miles from an NGS surveyed airport. The "11" identifies the horizontal and vertical geodetic datums for all data in the file (see fields 9 through 12).

96A

Same as for an airport file.

.TXT

The extension .TXT will be the same for all files.