View Full Version : Calculating Bearing/Distance

23rd Mar 2010, 14:31
What is your favorite calculator for determining great circle bearing/distance when you have the lat/long of two points?


23rd Mar 2010, 14:53

The INS or the IRS/FMS was my favourite calculator. We also had tables which gave the Initial Great Circle Track and the average track between waypoints 10 degs apart at various Latitudes, and the GC distance between them for cross checking.

I suppose there's an APP for the iphone now is there?

24th Mar 2010, 17:09
If using a PC or a laptop, compsys21 from naco.faa.gov/index.asp?xml=naco/online/compsys

I have the Andoyer-Lambert method programmed into my hand held calculator. Formulae courtesy of the Admiralty Manual of Navigation, HMSO.

25th Mar 2010, 00:41
A PC App is exactly what I want, Mathy; thanks heaps. I'm downloading it right now.

Yeh, I used to use the DC-10 AINS-70 RNAV for this job back in the 1970s and 80s.