INSTRUMENT FLIGHT RULES WORKBOOK
While navigating with a VOR, a pilot can know the aircraft's magnetic direction from a VOR
facility, but the only time the pilot will know his/her exact geographical position is when directly
over the station. However, by using two VOR facilities, the pilot can define a navigational fix by
the intersection of two radials from the VORs.
Since TACAN provides course and distance information from a station, a pilot has the
information needed for precise fixing of position at all times. A TACAN fix is defined as a
radial and distance from a TACAN station.
In Figure 1-29, the fix is on the TACAN's 090 radial at 20 DME.
Figure 1-29 TACAN Fix
1-34 INTRODUCTION TO AIRBORNE NAVIGATION AND COMMUNICATIONS
EQUIPMENT AND PRINCIPLES OF OPERATION