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Re: Tvmdc
From: Chuck Taylor
Date: 1997 May 06, 18:05 EDT
From: Chuck Taylor
Date: 1997 May 06, 18:05 EDT
On Tue, 6 May 1997, Millard Kirk wrote: ... > I know this has been lengthly, but I have a couple other questions: > > 1) How is desired course plotted on charts? True or Magnetic? The course on the chart (the course line itself) is the same either way. How it is LABELED is another story. The book answer is to label all courses with respect to true north. For one reason, magnetic variation changes from year to year, and a compass course computed 10 years ago may not be accurate today. For another, the accepted standard practice is to label all courses as true, so anyone looking at the plot will expect it to be so (such as your brother-in-law, the professional mariner, who has graciously agreed to stand all the midwatches on your next passage. :-) ). > 2) When one has a Chart that has only the true markings, no compass > rose, how is course usually plotted? True or magnetic ??? Plot and label it as true. Compute the compass course and enter it in your log (there should be a column for it, as well as columns for true course, variation, magnetic course, and deviation, all in the proper sequence). Chuck Taylor Everett, WA, USA ctaylor@XXX.XXX =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= =-= TO UNSUBSCRIBE, send this message to majordomo@XXX.XXX: =-= =-= navigation =-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=