That question has also been asked, and answered, before.
Did you try searching this group's archives, via Google?


Well that was a somewhat predictable answer fro you.

But again, yes i did look around google and i did not find anything.
I did find some formulas but most of them incomplete or simply did not have
an explanation to go with them.

I searched, "Great circle intersections", "Latitude Longitude intersection",
without great success.

Regards.
Sims