NavList:

H.A.C. van Asten, you wrote:
"My DR track is to point A in the Pacific . Just before reaching A..."

Right away in the first sentence and a half, I find what you're saying confusing. You say your DR track is "to" point A, but then you say that you haven't reached that point. Do you mean that your course from your last DR position should lead you to point A assuming that your last DR position was accurate? If so, this is a rather round-about way of saying things. How far away do you think you are from point A ...before we move on to the rest of the example as given?

Next you wrote:
"I precompute time & coordinates of sunset for a point A-1 "

This A and A-1 stuff just makes your prose less readable. Why not just pick some specifics? Let's say you're flying from San Franciso, California to Honolulu, Hawaii. So Honolulu is "A". Where was your last DR position? How long has it been since your last reliable fix? Now where is this "A-1"? Just some point you've picked off the chart? How was it selected? As for the "time and coordinates" of sunset, I can understand calculating a time, but what "coordinates" were you thinking of? Also, what is the altitude of the aircraft? The time of sunset is rather sensitive to that.

More generally, can you cite any historical examples of aviators using the time of sunset in the 1930s? Are you just making something up out of thin air, or do you have evidence that such a method was once used?? Why would anyone choose to use sunset observations, which are notoriously difficult due to variable refraction and especially the extinction at high altitudes, when sextant altitudes are available?

Also, I notice that the Netherlands Wikipedia page on Amelia Earhart includes a rather long, muddled exposition that apparently represents your theory. Did you add that to Wikipedia?

-FER

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