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    Practice problem
    From: Sammy Chan
    Date: 1999 Dec 07, 09:57 EST

    I am working on the book "Practical Celestial Navigation" by Susan P. Howell
    and I have a question about one of the exercises in the book.
    Specifically, in exercise 7 problem 5, the altitude and azimuth calculated
    for the Sun LL sight given by the answer in the back of the book
    disagrees with my calculation. However, if I recalculate it with an
    assumed latitude one degree higher, I get the answer in the book.
    What am I doing wrong?  Here is the problem:
    The 1500 DR is at 36 deg 20' N and 156 deg 16' E.
    W.E. on Z.T. is 47 sec fast. Height of eye is 6 feet, I.C. is 0.
    The Sun LL sight at W.T. of 12-16-13 is Hs=73 deg 39.7'
    Local date is 6-Jul-76
    A summary of my calculations follows:
    GMT 02-15-26
    Date 6-Jul-76
    GP of the Sun is GHA 212 deg 41.7, Dec = 22 deg 41.3 N
    AP used is 36 deg N, 156 deg 18.3' E.
    LHA is 9 deg
    Ho is 73 deg 53.0'
    The intercept from HO 229 is 40.9 Nm away at 212.9 deg.
    If I use an assumed latitude of 37 deg N, then I get
    a = 10 nm T at 211.1 deg. which is the answer given in the book.
    Any comments?
    Sam Chan
    

       
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