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    Re: One Assumed position or Six?
    From: Greg Rudzinski
    Date: 2017 Feb 7, 13:43 -0800


    There are many ways to perform sight reduction. If using inspection tables such as Pub 249 or Pub 229 then there will be a different assumed position for each observation to get the needed whole degree of LHA.  When using Pub 211, pocket calculator, trig log tables, or slide rules then any assumed position can be used which would include the same assumed position but I prefer to use the DR position as the assumed position so that intercepts remain short on the plot.

    Greg Rudzinski

    From: Mike Freeman
    Date: 2017 Feb 7, 03:55 -0800

    Having completed an initial study of my little book on celestial navigation I understand the following.....

    Entry arguments into AP3270 requires whole degree of latitude (closest to DR latitude), and whole degree of LHA. Adjusted DR longitude to ensure whole degree bearing in mind GHA of HB. This assumed position is plotted onto plotting sheet and Hc is derived from this position from AP3270. If Ho is same as Hc - BINGO! If Ho greater move position closer to HB. etc.

    I had concluded as a result of needing a whole degree for LHA for entry into AP3270 and each selected HB having a different GHA I would need a different assumed position for each LOP. HOWEVER... Either in a reply to one of my previous posts or in a PM I received someone said "use only one assumed position". Really confused as how to use the same assumed position for all the LOP's


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