NavList:

Except, the only way that Noonan coule have established the notorious 157-337 approach line of position was from a sun sight taken between 30 minutes and an hour after sunrise at Howland. So he definitely did get at least one, and possibly more, sun observation. This would have eliminated the DR uncertainty in distance along track (approximately east and west) leaving only the cross-track DR uncertainty since the last possible star sights about one hour and a half earlier at the time of twilight. see:

https://sites.google.com/site/fredienoonan/discussions/explanation-for-why-they-missed-howland

gl

--------------------------------------------------------------------

John -

Thanks for a definitve word on long range RDF. 

As I recall from the Long's book, (Amelia Earhart, the Mystery Solved) Amelia and Fred unloaded a fair amount of equipment to save weight - including a raft, and smoke bombs.

NavList went into this extensively a few years ago and my conclusion then was that Fred did not get an early morning sun sight as he ran out his DR approach. Had he, his LOP would have shown whether he was east or west of Howland. 

I'm a retired offshore sailor and celestial navigator. My experience with aircraft sextants is solely landborne, but several in the forum have done it aloft. Bubble sextants seem to give about the same results from a small plane as plastic marine ones do from small sailboats.

Hewitt