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Navigation, the
Art of not being Confused
Someone once said
that if you're lost no one can help
you; but if you are confused maybe you
can help yourself. Any self respecting
navigator should never admit to being
lost, confused yes, lost ?, never.
The tools of the
trade.
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Maps
The desire to learn
has developed an explorative trait in
the human personality and when we learn
we like to pass that information to
others, maps are a way of doing just
that. Cartographers, people who make
maps, collect information and create
for us a picture of the land. Maps have
existed for centuries, becoming more
refined and accurate as our knowledge
of a region increases. Some of the developed
countries are so well mapped that individual
houses and small features are now marked,
some wilderness regions still contain
areas that are like the dark side of
the moon to many of us and maps of these
regions are far from detailed.
Originally on calfskin,
vellum or parchment modern maps may
be printed to a very high standard on
waterproof materials or simply loaded
on a CD-ROM and viewed on a computer.
However you see the map you are looking
at a massive piece of information, a
picture of the land, drawn at a fixed
scale allowing you to convert the information
into a multi dimensional image of a
place you may never have seen. Ansel
Adam's, famous for his photographs of
the American wilderness could tell from
reading a map the best viewpoints to
place a camera and what type of light
the aspect of the sun would give.
In the UK we have
one of the best series of maps available
anywhere in the world. The Ordnance
Survey department have measured and
improved the record of the British landscape
for years and now produce maps that
are the envy of the world. The benchmark
maps for the UK are the Landranger series,
covering the whole of England, Wales
and Scotland. Scaled at 1:50,000 the
Landranger maps give a large amount
of information and detail and each map
covers an area of 40 square kilometres.
The
newer Explorer series is designed for
the navigator who requires more information,
at 1:25,000 scale these are the most
detailed maps available in the UK and
will eventually supersede the older
Pathfinder 1:25,000 maps. Maps of a
scale larger than 1:50,000 give the
navigator some problems, limited space
restricts the amount of information
the map-maker can give. Contour lines,
which give the navigator an estimation
of the landscape in terms of angle of
slope and heights of hills can be very
accurate at 1:50,000 or 1:25,000, when
the scale increases to 1:100,000 or
1:250,000 the amount of space for detail
is limited. For hillwalking or climbing
large scale maps are not recommended.
The OS Grid System
is unique to British maps, the ground
area shown is divided into squares,
each with a unique reference code. This
square is then subdivided again to give
a 'six figure ref number' this will
be a point that cannot be mistaken for
any other. Another development in the
UK has been the production of dedicated
walkers maps from Harveys, two series
are currently available, the Walkers
series at 1:40,000 and the Superwalker
series at 1:25,000. The maps use the
OS grid system and contain information
regarding the terrain and ground features
in addition to contour information and
vegetation. Printed onto a waterproof
base the maps are ideal for walkers,
climbers and mountain bikers.
The Harveys maps
employ the OS grid system for navigation
and map references. In other parts of
the world map information can vary tremendously,
some remote areas have only simple maps
with little detail, most parts of the
developed world, Europe, the United
States for example are covered by excellent
maps. Some important areas such as the
Himalayas have some high quality maps,
a series of Austrian maps cover the
South American Andes but other areas
can be very poorly served.
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Compass
The fundamental
navigation device using one of the basic
forces of nature, magnetism. A long,
thin magnet able to rotate freely will
always point to magnetic north. Wherever
you are on the surface of the planet
this rule applies. It gives the navigator
his main reference for finding out further
information, when combined with a modern
map it allows accurate navigation. The
early Chinese are credited with inventing
the magnetic compass, allowing their
navigators to sail and investigate the
whole of the western pacific coastline.
The
modern compass has become a highly refined
instrument capable of great accuracy,
using jewel bearings and a liquid filled
housing the compass needle will return
an accuracy of a single degree or better.
With a rotating bezels and scale marking
on the baseplate map work and navigation
have never been easier, so why do people
still get lost?
No map and no compass
is one reason for getting lost, the
two items go together. Map and compass
and still lost ?, use your map at regular
intervals to check your position and
progress, don't leave it until your
are lost to figure out where you are.
Don't put your map in your rucksack,
keep it in a map case and refer to it
at regular intervals. Observation of
the passing terrain is another source
of bewilderment, if the map says you
should be in a pine forest and you are
walking across open moorland something
has gone wrong!.
Observe as you travel
and refer again to your map, half of
accurate navigation is about observation.
Contour lines drawn on a map allow the
navigator to 'read' a slope or hillside.
The closer the lines are together the
steeper the slope will be, with some
practice and observation it is possible
to visualise the landscape with some
accuracy.
The
ability to read contour lines gives
you the ability to avoid very steep
ascents and descents, where contour
lines become joined on the map you are
looking at severe slopes and possibly
sheer cliffs and dangerous ground. Some
compasses are fitted with a clinometer
which allows measurement of the slope
angle to add another level of accuracy
to your navigation. The map and compass
represent a major asset for safe travel
in the outdoors, their proper use will
keep you out of trouble.
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GPS
GPS is an abbreviation
of Global Positioning System, the system,
which consists of satellites in fixed
positions above the earth, provides
a receiver with signals which allow
it to calculate its position to a high
degree of accuracy. Initiated in 1972
the system is global and is the main
source of satellite navigation data
to the professional, military and recreational
navigator. GPS sets are now found in
almost every outdoor shop in the world
and for sale at ever lower prices their
use in the outdoors is constantly growing.
Use
of a GPS receiver is another important
way of accurate navigation, misuse of
a GPS receiver will lead to trouble.
Using advanced triangulation methods
your receiver only needs to 'see' two
or three satellites to give a usable
position fix. The US military, who happen
to own the satellites, degrade the degree
of accuracy from an error of 100 metres
to 40 metres. This gives a maximum accuracy
at worst of 'within 200 metres' of position
fix anywhere on the surface of the planet,
not bad!. This selective switching of
the accuracy of GPS signals will soon
change to give a higher level of accuracy
on a permanent basis. Although some
advanced GPS receivers have features
such as map integration showing your
position on a map rather than as a reference
in Lat/Long or OS grid these sets are
mainly used in marine environments due
to the various boxes and batteries needed.
Most ground navigation
is done using simpler hand held receivers.
The Magellan 2000 is a perfect example
of a modern GPS set, about the same
size as a mobile phone the Magellan
2000 is a 'mini' computer. The unit
can store over 100 positions and then
give you the information on a screen
as to how to reach any of them, the
unit can log positions on the move and
allow backtracking. Various screen displays
give a mass of navigation information
ranging from your current position to
your speed over the ground and time
to target destination. The most important
ability of any GPS set is to tell you
where you are.
Using a GPS without
a map and compass is a dangerous practice,
bearings given by your GPS receiver
need a good compass to follow accurately,
without a map in your hand terrain and
contour information is not available.
In short a GPS is an addition to the
navigators armoury and all GPS manufacturers
recommend the use of map and compass.
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| The Navigator
Being lost is often
just a state of mind, stop, gather all
available information from around you
and the problem is usually soon resolved.
Don't slog onwards in the hope of inspiration,
you have become lost for a reason, use
your brain and the tools at your disposal
to get un-lost. Tiredness can be fatal,
on high mountains loss of concentration
has seen walkers taking the wrong end
of the needle as north and then walk
off into a blizzard and big problems.
As I said at the
start of this article that you should
not become lost only 'confused, everyone
gets 'confused' at some stage, it could
be a whiteout, or travelling further
than you estimated, taking a wrong fork
in the track. Pay attention to the advice
that is available from books, maps and
compass manufacturers and you will shake
off your confusion, learn your lessons
well and you may never be 'confused'
again.
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