Gary----I'm not trying to be a dumb ass---one of the first radio messages stated "weather cloudy". And where did she pass over the Ontario for a fix? Did I miss that? Seems to me if she overflew the Ontario, she would have had some communication about that, at least to let someone know that she was on course. I understand DR, and you adjust your course by taking a fix on a landmark and compare it to your heading. BUT---what landmarks are there in the middle of the pacific? And---if it was cloudy, how was Noonan going to shoot a star sight? Last I saw, flying over the ocean at nite was pretty dark.
Yes, you did miss it.
At about 1030 Z it was reported that Earhart was heard on the radio saying "ship is sight." Some believe it was the Ontario and some believe it was the Myrtlebank. It is 1100 NM from the reported position of Ontario to Howland so the DR uncertainty is 10% of the distance traveled, 110 NM. There is also a disputed report that she reported seeing the lights of Nauru at about the same time. It is only 990 NM from Nauru to Howland which would reduce the DR uncertainty to 99 NM.
-------------------------------------------------------------------
“A Ship in Sight Ahead”
AE reported seeing “…a ship in sight ahead…” at about 1030 GMT, according to Harold J. Barnes, officer in charge of the radio station at Nauru Island who copied Earhart’s message.(70)
In a letter from Mr. T. H. Cude, Director of Police, Nauru Island, to Dr. Francis Holbrook of Fordham University, he stated he heard AE broadcasting to Harold Barnes, Chief Wireless Operator at Nauru Island, several times between 10-11 PM that she could see the lights on Nauru Island. The lights she referred to were the flood-lights strung out along the two 1,000-foot cableways situated on top of the island to permit mining at night. (71)
https://tighar.org/smf/index.php/topic,555.msg9489.html#msg9489-----------------------------------------------------------------------------
You apparently do
not understand DR, since what you described is "pilotage" and there are no landmarks in the middle of the ocean so you cannot navigate by pilotage, you must DR between celestial fixes.
At 1623 Z Earhart reported "partly cloudy" which is good enough for celestial observations. Also, just because she reported overcast at one point, that report does not prove that it was continuously overcast, especially since the weather forecast did not forecast any storms on that part of the leg to Howland.
From 1623 Z to 1912 Z the plane traveled only about 360 NM, 10% of which is 36 NM plus the uncertainty of the celestial fix of 10 NM makes the total DR uncertainty at 1912 Z only 46 NM if a fix was obtained about 1623 Z. See my
more complete explanation here.Yes, it
is pretty dark over the ocean at night, give it a try sometime.
gl