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    Re: Nav Exercise #4- Amplitude of the Sun
    From: George Huxtable
    Date: 2008 May 24, 18:06 +0100

    Jeremy wrote-
    | Here is an example of one of those archaic amplitudes.
    | A ship is at sea and its DR Latitude is 14 degrees North.  At about
    | 0830 UTC on 6 May 2008, an amplitude of the sun is observed while the
    | body is on the celestial horizon giving a bearing of 288.0 deg per
    | gyro compass.  Local variation is 2.0 deg East.  The ship is heading
    | 208 deg per gyro compass and the magnetic compass heading is 207
    | degrees.  Determine Magnetic Compass Error, Gyro error, and Deviation
    | at that heading.    Please let us know if you used tables or formula
    | to find the amplitude value.
    I've had a go at this problem. But, because of the way the World turns, in
    my time-zone I can get to it long before the American contingent gets a
    If I get it right, it will spoil the problem for others. If I get it wrong,
    everyone else gets a chance to scoff (not that I mind, really).
    So I'll put my answer on the back-burner, for now. But to prevent me
    backtracking, and claiming that I had it right all along, let me say this.
    That if I add together the three quantities that Jeremy asked for, paying
    regard to their signs, it comes to 1.6 deg West.
    My calculations tend to be error-prone, and I got Jeremy's second problem
    wrong. I tend to get the principle right, but make careless errors in the
    numbers, particularly in the sexagesimal stuff. That time I got a simple
    subtraction in the minutes quite wrong.
    contact George Huxtable at george@huxtable.u-net.com
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
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