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    Re: Alternate theories on Noonan's navigation
    From: h.a.c. van Asten
    Date: 2012 Feb 11, 04:49 -0800

    May 25th , 2011 , Mr. Lapook criticizes the contents of a series of articles on the Earhart-Noonan incident of July 1937 . The main problem concerning the article(s) Mr.Lapook was wrestling with , is that he did not identify the difference between a technical review on a specific navigation issue , and an ad fundum review on the same issue , the latter along the paths of the science and practice of navigation of the era . The first review can be made by any navigator being conversant with reading his tables without any further questions put forward . The second can only be made by thoroughly studying any background that may have brought a navigator to the decision he has actually taken . Mr. Lapook´s main problem concentrated on the sunset - sunrise fixes appearing on stage in the articles . Very good : for air navigation , although mentioned in NIF-1944-Emergency Section , the method is intricate , time consuming , unreliable andsoforth . Sea navigators however , and Noonan was one , try to turn te sunrise-sunset fix to reliability until today´s day , be it for non-commercial use only . Lapook´s scepticism has in the mean time been quenched by his own exploration about an alternative track of the aircraft beteen Lae and Nukumanu Island , depending on a formerly erroneously notation of coordinates (by Balfour , Chater) . A 0519 from aboard radio message placed the flight over an unidentifiable pair 150.7-E/7.3-S . When reading 157-E / 7-03-S according to navigator´s usage to register in degrees and minutes , before the electronic calculator appeared , the coordinates pair is for the village of Ghaghara on Choiseul (Lauru) Island , eastern coast . Herewith the 0519 message acquires reality : mr.Noonan avoided the heavy rain squalls as predicted by the last received weather forecast , by altering the first track Lae-Nukumanu via Gagan on Buka Island to Lae-Ghaghara-Nukumanu via the precomputed sunset fix , also like originally allowing for a last position check before nightfall . From Ghaghara to the sunset-on-board coordinates 159-07-E/04-33.5-S the distance was 226 mls , allowing for 2 hours {at} 113 mph ferry speed which is slow , but one neared the storm depression in the Nukumanu region from the south . At 0718 GMT (watch time of mr.Chater , sunset was 0719:30 GMT) the aircraft was evidently close to the pre-fixed position , whereupon Noonan could safely order the position communicated by the also precomputed coordinates. He clearly decided for the following practial solution : if deviated from your inital track and you have a good , optical , Ghaghara fix available , you fly time-speed-distance DR to your initial next intended fix , you check by sun position lines , and arrive in the sunset region . No observation necessary : a glance at the setting sun and you are back on track within the margins of air navigation since the accuracy is better than by an observation itself . At sunrise next morning a same scenario may have deployed : fly from Nikunau , Beru , or Tabiteuea to your precomputed sunrise fix {at} 150 mls off Howland and if you see the sun actually rise or not : your watch {at} 175453 GMT indicates where you supposedly are . The 2008 EJN article shows that you may be actually 10 miles eastwards in error . A 3rd article , EJN Dec 2011 (davidkbowman.com and go to technical articles) shows that it was (Lae-Nukumanu detour or not)impossible to reach other islands than Howland , or Baker , so that the Earhart crew , in the favorable event , alighted the aircraft on the high seas in the immediate (60 mls)Howland vicinity . H.A.C.van Asten
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