Author
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Topic: Good Fix without a DR?
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Nathaniel
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posted July 21, 2015 11:38 AM
All the exercises in the book, that are non LAN require a Dr-lat/Dr-lon & running fix procedure, but is there any way of getting a good fix in the open ocean if you lost them? The reason why I'm asking is I'd like to apply celestial navigation to the desert & I was wondering If I was stranded out in the middle of nowhere with no coordinates, if it was possible to get a good fix just by using the stars/planets?
From: Sweden
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David Burch
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posted July 21, 2015 12:14 PM
You can use any nearby position for the assumed position and end up with an accurate fix.
One good exercise is take sights from the mid pacific (ie get the results from www.starpath.com/usno) then assume you are in NYC, and just carry out the normal procedures. you will get large a-values, then just make a small scale chart to plot them, then use that fix as the DR to reduce them again.
In a couple iterations you will find your right position.
In short, however, you will always have some coordinates... and they will indeed be much closer than NYC.
Put another way, unless you are unconscious for a long time in a fast moving vessel, you will always know where you are to within a few hundred miles.
For example, think of a town that is somewhere about 100 miles from you now, and ask yourself what you would have to do, and for how long, to not know if you were in that town or where you are now.
From: Starpath, Seattle, WA
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