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    Re: Moonrise video
    From: Gary LaPook
    Date: 2013 Apr 30, 08:17 -0700
    Mr. van Asten, for more than two years I have asked you to produce any flight navigation manuals or textbooks from 1937 or earlier that mentions using your "sunrise/sunset" method and, in spite of your claims that you have over a hundred such references, you have never produced even one! Nor have you produced any such manual describing your very complicated and convoluted methods of celestial navigation computations. Nor have you produced and marine navigation manuals supporting your theory.

    As for your trying to wiggle out from your prior adamant  claims that the Nukumanu position report was from a sunset line, you are stuck with what you have said over and over again, that the observation had to have been made at exactly 0719:30 Z (no other time works for your theory) and yet that position report was RECEIVED in Lae at 0718 Z, a full minute and a half earlier. Also, as I have pointed out to you in the past, observations in flight take about three minutes and the middle time of the observation period is used for the observation time. This means that an observation for 0719:30 Z actually would have covered the period from 0718:00Z  through 0721:00Z so the report was RECEIVED at Lae at least a full three minutes prior to the completion time of the observation and this leaves out the two or three minutes time necessary for averaging the sights and comparing the result with the precomputed altitude graph of the sun making the RECEPTION of the report a full FIVE or SIX minutes earlier than the time that the observation could have been completed! That position report was actually based on looking out the window and seeing the western end of Nukumanu Island.

    You expect that Noonan should have memorized the refraction correction for zero degree altitude, why, since even marine navigators did not take observation that low. Do you expect that he also memorized all the refractions corrections for 5°, 4°, 3°, 2°, and 1° since these were not provided in the refraction correction tables that he actually used which were contained in the 1937 (and earlier) Nautical Almanacs, and Dreisonstok (which are in the inventory of contents of the aircraft) and in HO 211, HO214 and the Weems Line Of Position Book, all limited to altitudes of six degrees and higher. Your original way for dealing with this "inconvenient truth" was to claim that Noonan used the sunrise time table from the Nautical Almanac for his computation of the time of sunrise since this table already incorporated an allowance for refraction and you only switched to the "memorized refraction table claim" after I demonstrated that the sunrise table did not provide for the precision that you claimed for your computations. Nice try!
     You have also not explained how he could have known the refraction correction for a sunrise observation taken from altitude since such an observation is actually below zero, a minus one degree and 37 minutes from 10,000 feet, and the refraction for that altitude is 51 minutes but this information was not published until 1951.

    gl

    --- On Tue, 4/30/13, h.a.c. van Asten <hac.vanasten---.com> wrote:

    From: h.a.c. van Asten <hac.vanasten---.com>
    Subject: [NavList] Re: Moonrise video
    To: garylapook---.net
    Date: Tuesday, April 30, 2013, 6:01 AM


    Any ex-marine air navigator of the era certainly knew about the for the sun zero altitude refraction , then figured 37 arcminutes . Be it not from H.O.208 or other tables , every textbook and the nautical almanacs contained chapters on the subject . Conyers Nesbit , professional navigator , in articles (*) and a book refers to mr.Noonan´s supposed ability to derive a more or less accurate geographical position from observing sunset and sunrise . It is not even necessary to observe for the instant : if the time-position group is precomputed and sunset-sunrise superficially observed from an aircraft , one acquires an indication for being with acceptable uncertainty in the vicinity of the precomputed coordinates pair . Mr.Noonan may have used this fashion when near Nukumanu Island he announced his position at 0718 GMT (mr.Chater´s watch time) , whereas actual sunset was at 0719:30 GMT , as mentioned in the addenda on EJN articles of July 2008 and April 2011 . We do not know it by certainty , but he may have also used it for sunrise in the roads of Howland .

    (*) Aeroplane Monthly , Jan and Feb , 1989 .
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