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    Re: "Magnetic compass" program
    From: Lu Abel
    Date: 2014 Jun 04, 11:27 -0700

    In the North American English-speaking world, the usual convention is that T = true course, M = magnetic course, and C = compass course.

    This leads to the commonplace alphabetism  T V M D C,  where True course adjusted for magnetic Variation gives a Magnetic course, which is further adjusted for compass Deviation to give a Compass course.   

    I suppose TC, MC, and CC would be recognized, but I would go for the consistency of "C" at the end of each course designator rather than "MT" for magnetic.

    The traditional mnemonic for remembering TVMDC is "True Virgins Make Dull Companions" which, as you might guess, some find objectionable these days.    My favorite mnemonic goes the other way and harkens to the days of political corruption in Chicago where after an election the newspapers used to publish pictures of the residences of supposed voters -- graveyards.   So the mnemonic is Can Dead Men Vote Twice.     If you add "at Elections" you get a nice reminder to add easterly variation and deviation when going from compass back to true.   Oh, and "At Wild parties" added to the politically incorrect mnemonic for TVMDC  reminds one to add Westerly variation and deviation.


    On 6/4/2014 1:46 AM, Andrés Ruiz wrote:

    Thanks Greg,

    for the variables used, please see screenshot: Magnetic compass
    is it correct to use TC for true course, MT for magnetic, and CC for compass course?
    and other variables.

    best regards,
    Andrés Ruiz
    Navigational Algorithms

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=127901

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