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    Re: Need help to track down errors
    From: Gary LaPook
    Date: 2008 Nov 13, 05:12 -0800

    According to the email I got from the government office, the errors
    started in 1999, see attached:
    Mr. LaPook
    Thank you for bringing this error to our attention. It seems that the
    Sight Reduction Table generation code improperly formatted entries
    beginning with -0, inserting 00 instead.
    I am in the process of manually updating the electronic publications,
    which will be posted to our Web site in the very near future.
    The errant publications were originally produced and posted to our Web
    site in 1999. Which mean that, in their 8+ years of service, you are
    the first and only user to notice the error!
    Tim Doherty
    Office of Global Navigation/Technology
    National Geospatial-Intelligence Agency
    On Nov 12, 4:08 pm, Ken Gebhart  wrote:
    > To all List Members,
    > Need help to track down errors!
    > I have been made aware of  many errors on page 158 of Pub 249 Vol 2
    > Apparently all of the Hc values on the page are wrong!  For example,
    > for dec 0, LHA 0, Lat 26 (page 158), Hc is shown as 65 deg. When it
    > should be 64 deg by simple inspection.  All the other numbers are
    > also off by varying amounts as can be found by computation.  There
    > are some other errors too, of a different kind on other pages.  For
    > example, page 160.  Look at the column for dec 15 deg, and go down to
    > LHA 98.  By simple inspection you can see that there should be a
    > minus sign before Hc 00-25, but it is not there.  I believe this is
    > typical of many Hcs  near zero.
    > These errors are present in the US Government Edition, privately
    > published editions, and the PDF on the NGA website.  I have spoken to
    > the UK Almanac Office, and they report that the errors do not exist
    > in their equivalent to 249 V2, or their Rapid Sight Reduction Tables,
    > and can find no trace or knowledge of them.
    > I am asking anyone who has an older copy of this volume, to check it
    > for these errors and report the publication date.  Maybe we can track
    > down when they first appeared.  By the way, a friend did phone the
    > NGA to report this, and was told that �they would look into it�.
    > Thanks, Ken Gebhart
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