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    Re: Relative bearings
    From: Bill B
    Date: 2015 Apr 14, 19:20 -0400

    On 4/14/2015 6:46 PM, Greg Rudzinski wrote:
    > When working with true and magnetic bearings to be plotted on a chart
    > you will be using the pelorus 0° clockwise to 360°.  If doubling the
    > angle on the bow or using Bowditch table 7 (1981)/table 18 (2002) then
    > work port and statboard off the bow or stern.
    Got my pluses and minus mixed up.
    RB = TB + C
    TB = RB-C
    C = RB - TB
    Should read:
    RB = TB-C
    TB = RB+C
    C = TB-RB
    Either way, for port or starboard doubling etc. (0-180 off bow) do you
    call it "Relative Bearing Port or "Relative bearing starboard" or some
    other term like AOB port or starboard?
    My new (to me) pelorus has 3 scales on the card. The outer scale 0-359
    CW, the middle scale 0-359 CCW staring at 0, and in inner scale is
    offset from the outer scale by 180d. The card says to use the inner
    scale for the southern hemisphere, but having a reciprocal course scale
    may come come in handy.
    If would therefore be possible to pick off 0-180 bearing off the port
    bow from the middle scale.
    Thanks for the radian lead. I have seen it but not dug into yet as it is
    still Monty Python "Confuse a cat"affair with the new pelorus.

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