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Old 02-12-2014
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Re: ASA Coastal Nav Exam - HELP

Quote:
Originally Posted by knuterikt View Post
I have not tried to plot this but
No deviation still mean that you must take magnetic variation into account.
Also the yearly changes..
I can see that you plotted m, I would have converted to t(rue) before plotting.
In your case
Compass = Magnetic (since no deviation)
Magnetic != true (Because magnetic variation)

And if the distance between the two positions is different from your calculated position you must move your track parallel to the plotted course so your triangulation is correct.

I would be skeptic if your observed position after these two bearings is the same as your plotted (DR) position.

Sorry if I'm using different words than you are used to, I learnt to navigate in Norwegian..
Thanks for the reply, but this is an academic exercise. Deviation is not requested for this question, and therefore not relevant, because it is an exercise.

Variation is already factored in to the chart (look at the compass rose). I believe that we can safely assume, because it is an exercise, that the navigator is preforming these calculations in 1985.

I think that the central issue is that I have plotted a course, and am asked to plot a running fix at 1600 and again at 1620. I don't know when I left the starting location, and I don't have a second bearing to compute a fix...

wait a min...

Because I KNOW the intended course, I could assume that I am traveling parallel (or almost parallel) to that course. I KNOW the distance that I should have traveled over 20 min = 1.333 nautical miles. I suppose that I could find a place on the running fix that corresponds to 1.3 nautical miles.

Your use of english, and navigation terms are very good.
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USCG Licensed OUPV Captain, ASA 101/103/104/105 Certified Instructor - Also certified in Recreational Marine Electrical Systems
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