It has been my experience, both in the air and on the water, that
errors in time and distance lead more often to getting lost than
errors in direction. You know how time speeds up when you are busy and
slows down when you are anxious? When equipment or work load forces
you into navigating very simply, these perceptual shifts can quickly
distort you situational awareness.

When you are looking nervously for a landmark, the next similar thing
you see is going to look a lot more like the one you need to find than
it might under other circumstances. People usually start being lost
when they are exactly where they are supposed to be but expect to be
somewhere else. We think conceptually of being lost as having gone the
wrong way so there is an almost irresistible impulse to change
direction when things don't seem to be adding up. Most people who end
up lost weren't actually misplaced when they started getting confused.

There is a tendency to peer straight ahead. That's where the dangers
are, that's where the objectives are, that's where the next landmark
is. The most important information is to either side, however. When
navigating by dead guessing, course is easier to determine than
progress. You should never let any two landmarks on the chart, such as
the shores or peaks of islands, come into a range with out at least
mentally drawing the line on the chart and confirming that it agrees
with your expectations.

When I had three, one hour sessions to turn new sailors into
rudimentary pilots before turning them loose into the high workload
environment of Boston, I skipped time / distance calculations entirely
for actual navigation purposes. The boat goes this speed with the
outboard at full throttle. Set the dividers on the mile scale, walk
them to a quarter, walk back to confirm. Tick of 15 minute segments on
the chart with ETA's and guess the rest.

I did show them how to use the logarithmic speed scale (this was in
the days when a pocket calculator was a bigger investment than a GPS
with map is today) and suggested they calculate their speed between
know points as often as possible to refine their eyeball speedometer.
These boats had no speed instrument.

This isn't the way I would necessarily teach a full piloting course. I
was faced with creating minimum competence in an inadequate time. In
fact though, I used this system for all of my piloting. Years later,
when I started learning how to navigate in the air, I was taught
exactly the same method. When you have to do all your chart work in
10-15 second gulps between other tasks, it pays to keep everything as
simple as possible.


--

Roger Long