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    Re: Life raft questions - knowing only GHA and sun's rising or setting
    From: Ed Popko
    Date: 2018 Nov 8, 03:27 -0800

    Stan,

    Yes, an analemma would be handy.  Now we are using the Lindburgh-Weems watch as an example. So the pilot bails out with his life raft. We assume his watch keep running when he hits the water, manages his raft and gets in though they were not water proof per se.

    The bezel was already set to the minutes portion of the Equation of Time, the direction of bezel rotation indicated if EoT was fast or slow.  But even with presence-of-mind, he was not ikely to remember the EoT seconds.so already the Hour Angle error could be 15 minutes plus/minus.

    A potential way of guessing longitue with just the watch is to guess the local apparent time. Tony suggests extimating apparent noon.  But you could also estimate at sun rise or set the sun is six hours local time but that depends on your latitude and time of year. So this is subject to some big errors.

    Perhaps we have exhausted the list.

    Ed

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