Just to add to all these, does any country use QDR and QDM for tracking. ATC in my country for non radar environment aerodrome uses these q codes. They usually will ask us to track on the QDR of a navaid. The misconception here is that it is assumed that a QDR is the radial inbound to the navaid when in fact a QDR is a bearing to the station no matter where you are heading and the QDM is the heading to steer in nil wind to the station. Can anyone enlighten me on this.