SSTjumbo From , joined Dec 1969, posts, RR: Posted (13 years 3 months 2 weeks 5 days 23 hours ago) and read 2715 times:
Could anyone give me an accurate version of the Great Circle Formula and present it so it makes sense? Every site I go to seems to not know about the algebraic rule (grouping symbols, exponents, etc.) and presents it with different notations. I figure I would ask people in this forum because pilots need to figure out distances. Thanx!!!
Timz From United States of America, joined Sep 1999, 6896 posts, RR: 7
Reply 2, posted (13 years 3 months 2 weeks 4 days 4 hours ago) and read 2669 times:
Yup, Ed Williams site is helpful for that and other things too. Notice that you'll need to decide whether you want to assume the Earth is a sphere or a spheroid (the slightly-squashed sphere that gives more accurate results). The formulas for the spheroid are far more complicated, but Williams' site takes care of that too. If you have accurate WGS84 lat-lons for the airports you're interested in you can use his calculator to get distances accurate to-- well, to whatever the lat-lons are accurate to.