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    Re: Figuring Course given Lat/Long of destination
    From: Luis Soltero
    Date: 2000 Feb 27, 6:43 PM

    There are several ways to solve this problem.  3 come to mind
    a) Using plane sailing formulations which are very inaccurate due
    to reasons you mention below.
    b) rhumbline computations using meridionals which compute
    distances based on Mercator projections.
    c) great circle sailing which will compute the shortest distance
    between both points very accurately.
    Alton B. Moody in navigation afloat also discusses something called mid latitude sailings
    which if memory serves me right uses the mean of the two given longs
    in the calculation.
    Anyway, all these sailings are discussed in great detail with formulas and examples in
      ----- Original Message -----
      From- Ed Kitchin
      Sent: Sunday, February 27, 2000 5:49 PM
      Subject: Figuring Course given Lat/Long of destination
      An interesting problem appears in the latest issue of "Ocean Navigator" 
    Which asks that you figure the course to a destination given origination and 
    destination. It would seem easy to determine the difference in lat. (The 
    destination was over several degrees of lat.), but deg. of long. differ in 
    length as you change lat. One could simply take the mean of the two given 
    long. and use that, but that bothers me as not being all that accurate. There 
    is the error of the Macerator thing. You could use universal plotting sheets 
    and construct using a vertical representing diff./lat., then draw a 
    horizontal from the top of the lat. fig., representing the long. at the 
    destination, and draw a hypotenuse as the course line. (???) Are there any 
    mathematicians out there to
       give me a good formula to learn for this task? Thank you.
      Ed Kitchin

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