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    Re: Vernier sextant
    From: Ken Gebhart
    Date: 2007 Mar 6, 21:22 -0600

    Allow me to chime in on this a little.  Using the averager in the air
    is to compensate for a very regular and smooth motion. Typically, the
    navigator has his finger on the sextant knob, and tries to keep the
    body in the center of the bubble as the airplane goes through its
    motion.  He may begin with increasing the altitude up to a degree of
    change, and then to follow it down two degrees, and then back up two
    degrees, and so forth until the averager has run its two minutes of
    operation. Thus, he has compensated for the natural motion of the
    airplane. If the air is rough, he cannot keep the body centered, but
    he at least knows what the overall trend is, and does his best to
    regain collimation as the sight progresses.  Thus, the averager plays
    no part in compensating for the rough air, but only the natural
    motion of the airplane which the two minutes of time is predicated upon.
    On Mar 6, 2007, at 3:12 PM, Bill wrote:
    > Alex wrote
    >> However, on a small boat, which sometimes swings like crazy
    >> on the waves, I do not exclude that the averager may be of some use.
    >> One just has to experiment.
    > Thank you for the explanation.  Fascinating.
    > Do you feel one would stand a chance of keeping the bubble and object
    > aligned on s small craft in heavy seas?
    > Bill
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