Wally wrote:

That doesn't quite sound right - if the leg along the outer circle,
plus the leg along the inner circle, add up to a total of 180 degrees
longitude, then the end point would be opposite the start point.

This is wrong - it should be the *difference* between E leg on outer circle
and W leg on inner circle that gives 180 degrees...

Start at 89d 42.447m S (roughly)...

The 14nm E leg traverses 45.7d longitude.

Go 14nm S to 89d 56.447m S...

The W leg covers 225.7d longitude.

Do 225.7 - 45.7 to get 180, and then go N 14nm to complete the course. You
are now on the original lat, but 180 degrees away from your start point. The
distance from the start is twice the minutes from the start latitude to the
pole...

90 - StartLat = 17.553 minutes from the pole

....which gives a distance of 35.11nm from the start to the finish.


--
Wally
www.artbywally.com
www.wally.myby.co.uk