In the following figure, the physical location of a TACAN is printed on a TPC. If we are
tuned into that TACAN and we find ourselves on the 325° radial at 18 DME, we can accurately
fix our position on the chart.
Recalling that radials are magnetic bearings, however, we must be especially careful, in
areas of high magnetic variations, to correct for the magnetic variation and accurately plot our
true position if using a TPC.
We now find that the McComb 325/18 means more than numbers--it means we are
overhead the city of Brookhaven. This information is especially useful for orienting oneself
and answering the most basic question any navigator should ask himself: "Where am I?"
2-8 NAVAID POSITIONING