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    Errors in online version of HO249
    From: Gary LaPook
    Date: 2007 Nov 28, 01:33 -0800

    I recently posted a link to the government web site where you can
    download copies of navigational publications including H.O 249. I
    quote below the email I sent to that site:
    "Dear Sir:
    "Quite by chance I noticed an error in the on line edition of HO 249
    volume 2. I then looked for similar errors and found that there is a
    systematic error in both volumes two and three. For example, on page 5
    of volume 2 covering latitude 0� in the first column covering
    declination of 15� at LHA 89 the altitude given is 00-58'; for LHA 90
    the altitude is given as 00-00'; and for LHA 91 the altitude given is
    00-58' which is the same value as given for LHA 89! This is
    mathematically impossible. The problem is that the altitude for LHA 91
    should be negative 00-58'. The systematic error found all across the
    tables up to at least latitude 39� is that  all of the last positive
    altitudes tabulated should all be negative altitudes! This is also
    true for the values given for contrary name declinations. For example
    on page 163 of volume 2 covering latitude 27� in the first column for
    0� declination tabulated for LHA 91 an altitude of 00-53'; for LHA 90
    an altitude of 00-00'; and again at LHA 89 an altitude of  00-53'. The
    altitude for LHA 91 should be negative 00-53'.
    "I compared these examples with my printed copies of these tables
    printed in 1970 and these errors do not appear in the printed version
    which correctly label these altitudes as negative altitudes."
    Gary LaPook
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