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    Re: American Practical Navigator, Bowditch 2017
    From: Tony Oz
    Date: 2017 Jun 14, 00:25 -0700

    Dear Mark,

    Regarding the "1.22", "1.23" and "1.24" for the radar horizon - I'm sure it's because of the frequency range the radars use - which is very different from the visibe light.

    Regarding the "1.14 vs 1.17" (and related "2.07 vs 2.12") - those are, I guess, because of refraction and how much of it is taken into account. Someone was indeed measuring the effects properly - the rest - as usual with all the dogmas out there (Aristotle, etc) - were simply [mis]quoting numbers carelessly. That's my understanding. The formulas for the horizon distance that were tought in the institute look different from these...

    Regards,

    Tony

       
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