Thread: DR practice
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JAXAshby
 
Posts: n/a
Default DR practice

joe, you don't understand the definition of the term "DR".

From: (Joe)
Date: 7/16/2004 2:43 PM Eastern Daylight Time
Message-id:

"Wally" wrote in message
...
Joe wrote:

I suspect that the speed you're looking for is the speed that would be
sailed through the water to acheive the desired course - speed made good is
the speed over the ground, isn't it


Yes, Im talking about doing a DR plot SMG & CMG are the actual course
and speed you do.



(ie resultant of course/speed sailed and
drift/set)? I'll assume you're looking for course/speed through the water

to
acheive the desired course and speed in the given conditions...


If you want to sail a course of 080, at a speed of 10 knots and you
sail thru a current having an estimated set of 140 and a drift of two
knots


069 at 9.17 knots.


Sorry Wally you are incorrect.

If you want to sail a course of 095 through a current having a set of
170 and a drift of 2.5 knots, using a speed of 12 knots


083 at 11.61 knots.


Very close to the course to steer, and your speed is off by almost a
knot


You want to sail a course of 265 and a speed of 15 knots through a
current having a set of 185 and a drift of 3 knots


277 at 14.78 knots.


277 is way off, but your real close on the speed, but not right on.

Sorry you flunked

Next! Come on Jax... show us what a skilled offshore navigator you
are!
Our you just a big mouth blowhard!

It's just a simple DR plot... Mr offshore bigshot!