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    Re: Sumner's Line (Navigation question)
    From: Bill B
    Date: 2006 Feb 10, 02:33 -0500

    Fred wrote:
    > Well yes, he was courting disaster had he kept his course up to the
    > moment of spotting Small's light, lacking the LOP.  But lacking the
    > LOP, I expect that he would have stood off or similar, and lost time.
    If we believe that his true position was 8 miles/minutes south of his DR
    position, the distance to Small's lighthouse would increase by 20+ nm.
    That, added to the 27+ nm from his DR to Small's gets close to 50 nm.  Let's
    assume our Harvard man took a little over 20 minutes per calculation and he
    was making top speed during the calculations.  So a little over an hour in
    calculations, and a little under an hour in reaching Small's after the LOP
    was confirmed.  That's almost 25 kn, and fails my common sense test.  (But
    if I could keep up, I would grind for that skipper any day ;-)  I therefore
    imagine you are correct in your assessment--stand off instead of barreling
    headlong into rocks at 25 kn. 

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