If I ever kick off, Doug, I will pass the baton, pen or
whatever to you to continue the tradition of posting
questions.
Actually, I am posting these questions mostly for myself.
I've been studying this stuff for a long time. I first began
studying in 1991, took a serious stab at it in 1995, and
now that my boat is nearly ready for commerical duty
I'm looking at it again. I have had so many offers of
employment, both part and full time over the years, I
think I need to get off my butt and take the tests.
*****************
Have you seen the Set and Drift problems the USCG uses
on their Charting test?
I can rarely get "their" answer. They must use a computer
to mathematically calculate the result, because the thickness
of a pencil line, and errors with transfering the True Bearing
to the Compass Rose will throw you off nearly every time.
The points are close together and that decreases accuracy
also.
Set and Drift is one reason I've held off testing. For a long
time my confidence was shaken because I couldn't make
these problem work out, and didn't stop to consider I can
get all the other answers correct. The reason is the USCG
doesn't plot to find the solutions, they use mathematics.
I finally realized Set and Drift is only one question on the test.
My new strategy is to compare my Drift result with the closest
multiple choice answer and check the answer to be sure the
Set is going it approximately the same direction. If not I chose
the answer that most closely matched my calculated S&D.
Using this method, and picking the closest answer, I can
chose the closest answer and it will turn out to be correct
even if I can't imagine how anyone could arrive there
through plotting on a paper chart.
Think about what is involved in doing S&D mathematically?
You have to fudge the Longitude by the cosine of the
Latitude to model what you have on the chart. Then
process the DR track, convert that into a Lat/Long, and
then figure the distance, and calculate the angle. When I
get more time I think I'll do that for fun. I suppose it can
be done other ways mathematically using spherical
geometry--perhaps this is how the USCG calculates
the solutions..
Other people I know who have studied for the test,
simply skip that question completely, and focus on
the other problems, like ETA, speed-made-good,
etc. There are only 10 questions on charting and
only 7 needed to pass, so rather than spend hours
plotting Set and Drift, people skip it completely.
Bart
"DSK" wrote
Bart, thanks for posting these questions. You've done this a number of
times and it's a great refresher, I wish it led to some at least
half-serious discussion.
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