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    Re: Relative plotting vs Geographical plotting
    From: Herbert Prinz
    Date: 2002 Jan 12, 3:07 PM

    Brian asks:
    >> Now who's right?   <<
    That's easy. Capt. Kliment is 100% right under inland rules, and you are wrong
    under COLREGS!
    An overtaking vessel (i.e. coming up from more than 22.5 deg abaft the beam) has
    to keep clear of the vessel being overtaken (no matter what kinds of boats are
    Under COLREGS, if the cooperation of the vessel being overtaken is required
    (such as in a narrow water way), agreement must be reached first via the
    exchange of special "overtaking" signals (NOT "turning" signals, as you say!).
    If the vessel being overtaken decides to change course, it must sound the
    respective maneuvering signals _in addition_ to the former.
    It is interesting to note that this is the one single case where the COLREGS
    deviate from the concept of "signal of execution" and adopt the "signal of
    intent" from the inland rules.
    The notion of "windward" never comes into play in an overtaking maneuver.
    Unfortunately, the error to assume that it does, is common. There were some
    disappointed sailors in the Long Island Sound who thought they could force me
    into the wind by mis-applying Rule 12.a.(ii), when all they got from me was 5
    blasts of my horn. Private yacht club racing rules have no application on public
    water ways.
    Speaking of Rule 12... It is beyond my comprehension why we still have this
    rule. It made good sense at the time of square riggs, but it is totally
    anachronistic nowadays. Wouldn't life be so much simpler for everybody if Rule15
    applied to sailboats too? This discussion here originated from a radar plotting
    exercise. How, I beg, is radar navigation on a sailboat different from that on a
    power boat. If I am sailing in dense fog and see a plot on my radar, not only
    must I guess power or sail, but even what tack this plot is on! This is plain
    As to whether "one might assume that a person attending a traditional navigation
    list might [...] be operating a sailing vessel", let me say this:
    "Navis" means "ship". No connotation of sail, whatsoever. "Traditional" is a
    weakly defined concept. But, most important, almost all the sailing vessels that
    I see on the Long Island Sound are, by COLREG standards, actually power vessels
    at least twice a day, and particularly so when engaged in an overtaking
    Best regards
    Herbert Prinz (from 1368950/-4603950/4182550 ECEF)

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