How to use a
compass
How to navigate in
foggy conditions
Fog makes things
difficult, and in some situations dangerous. When you hike, you will
probably some day experience these difficulties, and you'd better be
prepared.
The fog can come creeping very fast.
I have myself experienced from clear view to dense fog in 10
seconds. How fast this goes, depends on where you are.
In normal summer conditions without
snow, it is often not much of a problem. Unless you are supposed to
find a hut or something. The ground provides normally so much
contrast, you could do the aiming I have written about in
lesson
2. Just be very careful and accurate. Perhaps you also might use
some of the advice given later.
Winter conditions can make things a
lot worse, when there is snow on the ground. The fog is
white (or gray), the snow is also white. You may get a condition
we call a "white-out". It's too late to read the
terrain, and then the map isn't of much use. You can't see
anything anyway. You have no choice but to put blind faith
in your compass. I hope you knew where you were, because
you need to take out a good compass course, like described
in the other lessons.
If you are skiing, you should tie your compass to your arm
or something, so you can look at it for every step you take.
A rubber band is good. Check for more or less every step
you take that the compass needle is aligned with the orienting
lines. But if it is cold, make sure it doesn't affect circulation
of blood in your arm, because that will make you freeze.
If you are going on an expedition where you expect conditions
like this, you should perhaps consider a arrangement to
attach to your chest.
Let's consider a method to
enhance the accuracy in conditions when you can't aim at
anything.
If you are three persons in a row, like on the figure, and
the last one carries a compass (of course, it is better
that all three carry a compass, but the last one has command),
he or she will see if you get off course because one of
those in front of him or her will not be covered by the
person in front. On the figure, the situation to the left
is ok. The person on top is heading forward and but he sees
only the person in front of him or her. In the situation
to the right, it's time to stop. The last person can see
the backs of both of them in front, and they are about to
leave their course.
The further apart you go, the more
accurate this method is, but it is also very important to have good
contact. Sometimes the conditions get so bad there is no way to
maintain contact, and then, the method may fail.
There is also another method for two
people, where the lead person goes out on a compass azimuth, as far
as the visibility will allow. The person behind stands still and
watches the lead person, telling them if they are in the correct
line or not. Once they have moved correctly into line they then
stand still and the back person joins them. They then have their
turn to move out ahead on the azimuth, and the whole cycle repeats.
The problem with this method is when the visibility is very bad, the
lead person can't go more that a few meters, and it would be
dangerous to loose each other.
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