NavList:

I did not finish commenting on the "No DR Position  How Do You Get a Celestial Fix"  thread because I became thoroughly confused. The more I think about it the more confused I become. The problem is this:

The intercept "distance"  is a measure of angle. If the bearing is N-S then the intercept is a dlat and the  scale is 1arc minute = 1 NM. If the bearing is E-W the intercept is a dlong and the departure scale  is 1 arc minute =  1 * cos lat  NM. So far so good. But what if the azimuth is, say, 45°. The intercept scale must be a function of lat somewhere between  1 and cos lat.

I belive that the intercept is always plotted at the lat scale, regardless of the azimuth. I cannot recall reading anything indicating otherwise.

I believe that I understand dlat, departure, dlong and plane and mercator plotting sheets but I cannot get my head around a line that seems to be neither one scale nor the other.

Any comments would be appreciated.