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Lu wrote:

> Traditionally in ocean navigation, DR is based solely on speed, time,

> and course steered.

> If one is sailing with a known leeway or set and drift of current,
one
> adds that information to the DR to arrive at an estimated position
> (EP). Usually a dotted line is drawn between DR and its corresponding

> EP and the information used to determine the EP is labeled on the
line
> ("leeway est 4 degrees" or "current, set 295, drift 0.5 kts")

Gotcha... I'd seen both terms batted around in the navigation
literature, but never really bothered to check on the actual "formal"
definition for each term - thanks for clarifying that for me.  :-)

--
GregR

--- Lu Abel  wrote:

>
> Traditionally in ocean navigation, DR is based solely on speed, time,
>
> and course steered.
>
> If one is sailing with a known leeway or set and drift of current,
> one
> adds that information to the DR to arrive at an estimated position
> (EP).
>   Usually a dotted line is drawn between DR and its corresponding EP
> and
> the information used to determine the EP is labeled on the line
> ("leeway
> est 4 degrees" or "current, set 295, drift 0.5 kts")
>
> Lu Abel
>
> Greg R. wrote:
> > Clive wrote:
> >
> >
> >>Does  anyone know of a really good way of checking leeway?
> >
> >
> > Along those lines, is it common in ocean navigation to try to
> estimate
> > set and drift (and I'd guess true wind and leeway, too) and factor
> that
> > into the DR position estimate?
> >
> > I know that in aviation navigation we have to calculate the heading
> for
> > a given leg based on wind correction angle, but I've never seen any
> > reference to a similar allowance being made for that by our
> ocean-going
> > counterparts.
> >
> > --
> > GregR
> >
> >
> >
> >>Hi All;
> >>
> >>Back online again after a long while!
> >>
> >>Franks recent mail about using floating styrofoam reminds me that I
> >>suggested using this as a means of checking leeway (by back bearing
> >>on a floating paper plate) some while ago but nobody took this up I
> >>will try and revive it..
> >>Does  anyone know of a really good way of checking leeway?
> >>
> >>Clive.
> >>
> >>
> >
> >
> > >
> >
>
> >
>


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