Well funked,
It just so happens that I AM a real pilot and we determine our position in many different ways, such as radio Nav, GPS, and yes, good ole dead reckoning. In order to accomplish good dead reckoning, one must have a hyper accurate map. In "real" life, these are known as "sectional charts" and one does plot "precision courses" on them.
Just thought you'd like to know.
foggia