"Andrew Sarangan" wrote:
One thing look for is the difference between great circle distance and
actual distance.

It's pretty rare that GC calculations become significant for the kinds of
flights most GA aircraft are capable of making.

I just worked a pretty extreme example: 45N/68W (roughly Bangor, ME) to
45N/92W (roughly Duluth, MN). This is about 1000 miles, beyond the range
of most of our aircraft. It's also a route parallel to the equator, and
further north than most of us fly. All of these are factors that increase
the GC error.

It works out to an initial heading of 279 (true), compared with the
Mercator rhumbline of 270. That's a pretty small difference, and almost
certainly other factors such as terrain, weather, airspace, and possible
alternates are going to be more important.

Put together a few fuel-bounded legs in a row, and then GC starts to become
important for the overall trip (assuming it's mostly east-west).