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    Re: lunar parallax killed Amelia Earhart
    From: Paul Hirose
    Date: 2006 May 20, 13:12 -0700

    Royer, Doug wrote:
    > Were the
    > head winds grossly miscalculated? Thus putting them grossly out of position
    > and/or consuming much more fuel than they calculated or allowed for.
    The speed line they obtained from the Sun rising nearly dead ahead
    should have revealed any serious headwind, and Noonan could have shot
    course lines out his side window during the night.
    Itasca observed 7 knots of wind from the east.
    There seems to have been enough fuel. According to the Itasca's radio
    log, at 1912Z Earhart said "We must be on you but cannot see you." She
    had enough fuel to fly until 2400Z.
    A scan (about 750 k) of one of the planning sheets is on the web:
    (The direction is backward because the flight was originally going to
    circle the world eastbound. After the delay due to the takeoff mishap,
    they decided to reverse the direction.)
    Modern coordinates for the beginning and end of the flight are:
    Lae              06 44 S 147 00 E
    Howland Island   00 48 N 176 38 W
    Using those coordinates, my GPS agrees with the planning sheet data to
    practical accuracy. (The speeds and distances on that sheet are in
    statute miles.) But look at those 15 waypoints on a great circle track!
    It seems a pointless refinement for a flight so close to the equator. I
    would eliminate all those little course changes, and plan the flight so
    Earhart could fly a constant magnetic course all the way from Lae to
    Though I'm skeptical about the lunar parallax theory, the author of that
    page does have a good point: the Moon was available. But its altitude
    may have been too high for convenient use. When Earhart said, "we must
    be on you," it was about 65° high at Howland. I don't know if Noonan
    would have been able to shoot it.
    By 2100Z the situation would have improved, with the Sun and Moon both
    about 45° up, and a 125° split in azimuth.
    > It is interesting that the ships on station were able to receive some of
    > Earhart's calls but couldn't communicate with her radio. And how well did
    > her radio-direction finder really function? Was it calibrated and did she
    > really understand how to use it?
    According to that paper by radio engineer Hooven, "The people
    responsible for installing the radio equipment and instructing Miss
    Earhart in its use reported that they had difficulty in retaining her
    attention, and it became obvious as the flight progressed that she did
    not understand the frequency limitations of her direction finder, nor
    how to make proper use of it."
    Hooven also said Itasca's skipper received no clear instructions on
    exactly what radio assistance was expected, and never got any
    acknowedgement that the information he sent to Earhart ever reached her
    before takeoff.
    > Here is the title and authors of the book I read about this. It's
    very good
    > in technical and historical detail (although nothing is proved or
    > finalized). It most likely is at your public library as that is where I
    > picked it up.
    > "Amelia Earhart: The Mystery Solved"
    > Elgin and Marie Long
    Thanks for the tip. I was at a library Friday, but the book was checked
    out. (Their catalog showed Elgen, not Elgin, for the author's name.) If
    I ever get hold of it I'll post a book report.

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