NavList:

Hi David

Obviously I am missing part of the story hear and have read each reply without following the maths, though my maths knowledge is up to it.

Your last comment sort nailed it.

As an RNZAF navigator flying from Whenuapai NZ a common flight route was NZ to Hawaii non stop in a P3B Orion. Not quite as far as your mythical plot.

The flight was from 36S to 19N and we just grabbed a standard RAF merc chart and drew a straight line and flew.

No we needed a big runway but a Hercules C130 had the legs to do that flight and land on a small earth paddock and take off.

Here is a couple of real exercises I saw teased out a bit in the newspaper.

During the prime minister sent a civil airline from australia to south america to pick up australians stranded and the newspaper showed the concept of a GC flight. Of course I doubt anyone had a map of any use at these southern latitudes as a mercator is useless. A transverse mercator perhaps or lamberts conformal but doubt any available.

And the latest talk is a direct flight Aust to london by 787 dreamliner via a GC route over the pole.

Now that is really an interesting exercise.

Howard G