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    Great Circle Initial Course Boston to Wellington?
    From: Bruce J. Pennino
    Date: 2017 Dec 1, 14:06 -0800


    A New Zealand friend and I were just talking about a direct flight; distance and initial course from Boston. I easily calculated the distance using cosine D (distance) equation  from navigator's triangle and course using Cos A equation,etc. The distance is about 7,940 NM checked on-line and Cos A equation indicated Z about 215 degr. True. I looked at a globe and seems to make sense. But I wanted to check it with H.O. 208 Dreisonstok. Distance confirmed at about 7,920 ,NM, but initial course Z = 250 degrees?  Can't find a math error in either calc.  Initial great circle course is ???

    thank you and best regards.


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