Robert11 wrote:
Hello:

A bit confused over Great Circle directions.

I believe that if one is traveling from Boston to London via air along the
great circle connecting these two cities, he would Constantly have to adjust
his heading; e.g., one compass
heading the whole way won't do it.

Is this correct ?

So, now to my real question"

Let's say that there is an omni broadcast station in London, and that its
broadcast goes out in all directions.

I believe radio waves follow great circles when considering a spherical
globe.
True ?

Then, how would the chap in Boston, assuming he has an extremely directional
antenna, point his antenna ?

Would it just be the final angle along the great circle when it crosses
Boston ?

Looked, but surprisingly couldn't find any good links to any great circle
direction programs on the web.
Lots that calculate distances, but couldn't locate any that show distances,
etc., relative to my questions above.

Anyone happen to know of any ?

Much thanks,
Bob



Some basics:

http://www.ac6v.com/greatcircle.htm


A spread sheet program that should be easily adapted to other forms:

http://home.inu.net/davidstua/Lat_Long.htm


A java script calculator:

http://www.airways.com/java/coordcalc.html


A great circle distance calculator in Visual basic. I don't know if it
does angles of direction, though.

http://snipurl.com/l20q


Many different calculators, including Great Circle stuff:

http://www.martindalecenter.com/Calc...s1B_7_Nav.html



From the above site:

http://williams.best.vwh.net/gccalc.htm



mike