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: Traditional navigation by slide rule
    From: Bob Goethe
    Date: 2016 Nov 13, 13:10 -0800


    As for conventions for writing equations, you are right that computer languages all put the variable that receives the value on the left.  I got my elementary and secondary education before computers were ubiquitous, and the convention I learned in school put that variable on the right...along the lines of a2 + b2 = c2, rather than c2 = a2 + b2.  Writing Bygrave equations as I did simply came natural to me as I was seeking to develop a worksheet for use with a non-electronic method of sight reduction.

    As for the azimuth outputs, my worksheet is wrong, wrong, wrong.  Thank you so much for pointing this out!!  The mystery to me now is how I managed to always work out problems on my own where my method worked.  Those were clearly misleading results.  I have gone back to Gary LaPook's worksheet at:


    ...and his azimuth rules definitely work great for the first example you sent.  I need to go back and work some more problems myself, and get myself at home with Gary's azimuth rules, and make modifications to my worksheet.

    Again, Paul, thank you for pointing this out.

    Gary, do you have azimuth-rule suggestions for rhumb line calculations?  It seems likely that if I got azimuth wrong for great circle routes, I may well have gotten my rhumb line calculations wrong as well.


    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