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
    Multiple LOP using one sun sight
    From: T. Shanklin
    Date: 2005 Aug 22, 22:35 -0700

    I recently taught myself celestial navigation.  In working out a sun sight I
    recently came up with an idea for getting a better fix using only one sun
    sight (although it is so simple I'm sure people do it).  I calculate and
    plot one line of position using H.O. 229 and the whole degree Latitude and
    adjusted Longitude D.R. coordinates (as required by pub 229).  After that I
    reduce the sight using the formula provided in the Nautical Almanac
    (sinHc=sinDec*sinLat+cosDec*cosLHA*cosLat...&c.).  This method provides me
    with two different azimuths from two different ded. reckoned positions, thus
    two different L.O.P.s.  Of course the accuracy of the fix depends entirely
    on the one sun sight, so I usually graph/average out multiple sights for
    greatest accuracy.  It worked fairly well for me.  Is this an acceptable
    method in a pinch?  Anybody else do this?
      Also, I've been trying to practice with the 2102-D starfinder lately- I've
    been having a real hard time having the calculated azimuths (as per 2102)
    correspond with the actual azimuth.  Maybe it's just my compass, but I
    always seem to be fairly far off (up to 20 degrees), even when I have the
    correct star.  I have been adjusting for local declination (true N to
    magnetic N).  Any tips?
                                                             T. Shanklin
    Prime numbers are what is left when you have taken all the patterns away.  I
    think prime numbers are like life.  They are very logical, but you could
    never work out the rules, even if you spent all your time thinking about
    Express yourself instantly with MSN Messenger! Download today - it's FREE!

    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