VOR

This topic contains only those PANS-AIM requirements relevant for a VOR. For general PANS-AIM requirements valid for all kind of Radio navigation aids see topic Basic Data for Navaid.

For a VOR, PANS-AIM requires some specific properties as part of the minimum AIP data set. These are

...frequency,... zero bearing direction

In addtion PANS-AIM ENR 4.1. and also AD2.19/AD 3.18 require

for VOR, station declination to the nearest degree used for technical line-up of the aid

The diagram below shows the AIXM classes, including the relevant data types, needed to encode that information:

Frequency

The VOR.frequency attribute is used to code the value of the frequency. This can be any decimal value greater than 0. However, there is a coding rules that define a range of acceptable values.

The corresponding data type contains a uom attribute. For a VOR only the value equal-to 'MHZ' shall be used.

Station Declination & Zero Bearing Direction

The VOR.zeroBearingDirection is used to code the direction of the 'zero bearing' provided by the station. For example: magnetic north ('MAG'), true north ('TRUE').

The angular difference between the direction of the 'zero bearing' indicated by the station and the direction of the True North at the time the VOR station is calibrated is coded by the attribute VOR.declination.

In case the VOR is assigned to an AirportHeliport (see topic TBD) the magnetic variation of the VOR has to coincide with that of the related airport/heliport.

In some AIPs also the date when the station declination was measured is published. Unlike for magnetic variation there is no dedicated attribute for station declination contained in AIXM 5. Corresponding information can only be recorded using a Note.

According to PANS-AIM for VOR the specific station declination should be provided rather than the local magnetic variation. However, in many AIPs the magnetic variation is published instead. Coding Rules for VOR

Coding Examples

Example 1

In this Example the station declination of the VOR is published.

Example 2

In this example both the station declination and the magnetic variation of the VOR is published and year when it was measured.

For more examples see topic Navaid [NAV].