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I need to correct a typo in my prior post. The sun rose at Howland at 
0615 Itasca time, 1745 Z not the 1645 Z in my prior post.

gl
Gary LaPook wrote:
> Amelia Earhart (AE) attempted to fly around the world in 1937 at about 
> the equator. Some prior around the world flights had been made at higher 
> latitudes so encompassed a shorter route. The original plan was to fly 
> westward and refuel in the air over Midway Island since there was no 
> airport there, only a seaplane base. The Navy put the kibosh on that 
> plan because of AE's lack of the piloting skills for the in flight 
> refueling. The next plan was to fly westward including a leg from Hawaii 
> to Howland, about 1800 NM, where a runway was bulldozed for her use. 
> (There is speculation that this also furthered the claim of U.S. 
> sovereignty's over Howland and the other Line Islands. It may have also 
> furthered Pan Am's plans for routes across the Pacific.)  The plan was 
> for AE to be accompanied by Harry Manning as navigator and radio 
> operator and also by Fred Noonan as navigator as far as Howland and for 
> AE to continue on alone after that with Manning and Noonan to return 
> from Howland by ship. It is obvious that everyone appreciated that the 
> leg to Howland was to be the most challenging navigationally
>
> They flew from Oakland to Hawaii on March 18, 1937 (Z) as planned with 
> Paul Mantz also aboard, he was a technical adviser to AE. Noonan and /or 
> Manning took 14 celestial shots during this flight as well as a number 
> of radio bearings. We have the charts used on this leg. On the 
> subsequent takeoff with Manning and Noonan onboard AE lost control of 
> the plane resulting in a ground loop and significant damage to the 
> plane. The plane was crated up and shipped back to California on the 
> Lauraline for repairs at the Lockheed plant in Burbank California. It 
> was decided to reverse the route to travel eastbound after  repairs with 
> the toughest navigation leg to be Lae New
> Guinea to Howland. This necessitated carrying a navigator for the the 
> entire flight. Manning claimed that he had to get back to his full time 
> job as captain on a ship but he was supposed to have said that he had 
> lost confidence in AE's abilities so he did not participate in this 
> second attempt leaving Noonan as the sole navigator. Noonan did not have 
> Manning's radio skills which proved to be a serious problem later in the 
> flight. They flew from Oakland down to Natal Brazil. On June 7, 1937 
> they flew from Natal towards  Dakar Senegal but missed that destination 
> and landed about 150 NM further north at St. Louis. We have the chart 
> used on this flight showing five sun lines. 
> They then continued on around the world and arrived at Lae N.G. on June 
> 29, 1937. On the 30th the spark plugs were changed and other maintenance 
> accomplished. They had planned to depart the next day, July 1st, but 
> were unable to get a radio time signal so put off the departure until 
> the 2nd. They took advantage of the delay to do a test flight on the 1st 
> to check out the operation of the RDF which didn't work. They ignored 
> this problem and departed at 10:00 a.m. (ZD -10) on July 2nd, 0000 Z 
> July 2nd, for a planned 18 hour flight to Howland. This leg is 2222 NM 
> long and the course is 078� True approaching the island. The rumb line 
> and the great circle differ by less than one degree and one-tenth of a 
> nautical mile since the flight was along the equator. The Coast Guard 
> Cutter Itasca was off shore of Howland ready to transmit a homing signal 
> for AE to follow to Howland and had the capability of direction finding 
> on transmissions made by AE if she transmitted on the correct frequency 
> within the frequency range of the Itasca's equipment. Itasca had cabled 
> to Lae on June 28th listing the frequency ranges of its radios. Its RDF 
> covered only from 270 to 500 kHz. The Itasca maintained time with a ZD 
> of + 11.5. AE maintained two way radio contact with Lae for five hours 
> on her daytime frequency of 6210 kHz but contact was lost when she 
> switched to her night time frequency of 3105 kHz to attempt to call Itasca.
>
> AE's radio could transmit on 500, 3105 and 6210 kHz only but she could 
> tune her receiver to any frequency. Communications on he international 
> calling frequency of 500 kHz was in Morse code and neither AE nor Noonan 
> were proficient in Morse though manning was. Since they did not plan to 
> utilize Morse code without Manning ,the 250 foot long trailing wire 
> antenna used only for 500 kHz was removed in Florida to save weight. It 
> is possible that her radio might still have been able to put out a 
> significantly weakened signal of 500 kHz using the remaining antenna.
>
> Noonan and AE most likely planned to use radio navigation for terminal 
> guidance as they approached Howland since radio navigation gets more 
> accurate as you approach the antenna while celestial's accuracy remains 
> fixed. AE could have done any necessary radio work by herself so did not 
> need to carry Noonan all the way around the world if they had not 
> planned to use celestial, at least as a backup method for finding Howland.
>
> When they were unable to get the radio signals they needed it is almost 
> certain that Noonan would have turned off to the left to intercept a sun 
> line LOP to the northwest of the island. From sunrise at about 1645 Z 
> (0615 Itasca time) and for more than and hour afterwards the azimuth of 
> the sun remained 067� T so the resulting LOP ran 157-337� T. Noonan 
> would have intercepted this LOP and followed it to Howland using the 
> "single LOP landfall procedure" popularized by Chichester as "deliberate 
> error" and also known as deliberate offset. This method had sufficient 
> accuracy to allow them to find Howland and was taught to all flight 
> navigators and was used thousands of  times successfully during WW 2 and 
> after to find small island destinations. In addition, the moon was also 
> visible and provided  good cuts with the sun line to provide daylight 
> fixes.
>
> AE's last transmission at 2013 Z (0843 Itasca Time) stated they were on 
> the 157�-337 �LOP
>
>
> More later.
>
> gl
>
>   

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