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    Re: Which Cocked Hat?
    From: David C
    Date: 2019 Aug 2, 14:27 -0700

    Frank wrote

    Suppose you have a triangle from sights taken on bearings (true azimuths) of 0°, 270°, and 178°. Get out a piece of paper and draw the corresponding lines of position. Assuming some random errors in the sights, you'll have a long, narrow triangle with a short side on the west and two very long sides on the north and south. Next, if asked to indicate the fix many people without thinking on it much would select the center of the triangle. But that's wrong in every sense. The fix is very close to the short side. And this isn't some fancy mathematical argument. It's obvious if you take this case and replace the third azimuth with 180°. Draw it out, and you'll see why. This is 99% of the point of all those discussions. If you can see this, the rest is not really navigationally significant. All the rest is just mathematics mixed with confusion (some people bring math to the table, some bring intractable confusion).

    Sometime ago someone wrote that the position of the ship in the cocked hat was the point closest to danger. For ocean navigtion that is a simple solution to the problem.

       
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