Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: Position lines, crossing.
    From: Bill B
    Date: 2006 Dec 09, 21:58 -0500

    Peter wrote:
    > As to George's insistence that the ACTUAL position is not necessarily
    > located at the centre of a triangle, or other intersecting LOPs, this
    > does not seem especially helpful. As an example of how unhelpful it
    > is, Lu is now worrying about the precise statistical improbability
    > involved. Will this knowledge enable the calculation of a more
    > accurate position?
    It is indeed a guessing game and to some degree frustration IMHO.  No
    systematic errors or personal bias, you are *probably* in the cocked hat.
    No one-in-four statistics as related in my texts.  With systematic errors,
    then you may well be outside the cocked hat according to my texts.
    I am well aware George is far better read an educated on the topic than I
    will probably ever be, but it still seems a bit hit or miss in any case.  If
    I have done my homework before a long voyage and do not find personal or
    systematic problems, or instrument error, then I might tend to believe that
    after a month at sea that would remain true and trust a position within the
    cocked hat within certain limitations.
    That's an assumption. How do you know--really--unless you are comparing to a
    I recall a chapter in a book a friend loaned me--I don't recall the
    title--recounting of a month-long blue-water voyage by some yachtsmen.  The
    author pointed out that such-and-such was their best day yet. They covered
    192 miles where yesterday they covered 190 miles.  This was done with cel
    nav and running fixes. No GPS.  I had to laugh.
    Thankfully the sextant can be a bit more precise for coastal navigation, so
    it serves both purposes very well if taken with a grain of salt and dose of
    common sense.
    In the digital age where operating system and application interfaces must be
    relearned with each upgrade, it is comforting to have a tool in the sextant
    that meets my classic definition of a tool--a handle on one end and a use on
    the other. It measures angles well enough for the purpose at hand.
    The big plus being there are so many uses those angles can be put to.  For
    some tangential reason, UNIX comes to mind.  Referring to the various
    flavors of UNIX, one wag commented decades ago, "A good operating system
    needs standards, and the beauty of UNIX is there are so many to choose
    To post to this group, send email to NavList@fer3.com
    To unsubscribe, send email to NavList-unsubscribe@fer3.com

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site