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From: (no name) (no email)
Date: Wed Oct 13 2004 - 11:32:47 EDT
On Oct 13, 2004 6:33 AM, Jim Thompson <> asked about
teaching traditional techniques to beginners with electronic-only
viewpoints.
David Weilacher <> wisely suggested one try to
scare one's students a bit by pointing out that GPS units (or the batteries
they rely on) do die; waypoints can be mis-entered; rhumb lines can pass
through nasty patches.
I have introduced a few friends to coastal navigation since the arrival of
easy-to-use Loran-C and GPS. Few have shown any interest in performing DR
underway. However, I have always gotten them to agree that a non-trivial
passage calls for non-trivial planning. I have gotten them to learn basic
chart work, enough to be able to lay out buoy-to-buoy tracks and to measure
the resulting courses and distances; plus the ability to take off the
lat/lon of a charted object or plot a GPS position. I figure if they can do
this much, they are not completely unarmed.
The next hurdle is to get them to actually compare the GPS readout to their
intentions. One way to do this is to get them to compare the GPS's
bearing-and-distance-to-waypoint to the track they've laid out on the chart,
and to ponder if they agree sufficiently -- and if not, why not.
An alternative to plotting position from lat/lon is to take the GPS's
distance-to-waypoint and off-track readouts to plot their position on or
near the charted track. It doesn't require access to the chart's longitude
scale and works better on folded charts in tight spaces.
Finally, I try to get them to do something I always do: when plotting your
position (GPS, DR, EP, whatever), always extend a course line from it to see
what you're about to get into.
The hardest part is getting them into a routine; getting them to write stuff
down (notebook or chart); getting them to look ahead.
(Well, actually the hardest part is making beginners understand compass
deviation; to measure it; to correct it as much as possible; to allow for
it. but that's another battle.)
-- Peter
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