Mark Hansen wrote:


One of the problems is that GPS accounts for magnetic variations
differently
than the VORs do. Also I don't think GPS accounts for the fact that the
VOR radial are not exactly aligned with magnetic north (what is this
called?
variance? I can't remember - it's documented in the A/FD).

This would have an effect only if the procedure has you tracking a defined VOR
radial. There might be some such procedures, but I can't think of any at the moment.

All the airway segments (that's what we're talking about, right?) that I know of
have a defined point at each end of the segment. There is one and only one great
circle route between those two points. It's the same great circle whether you
follow it with a GPS or a VOR receiver.

Dave