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Essential land nav gear primer
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Baseplate compass modifications
Land nav crib
card (rev 09-19-08)
Ranger pacing beads
rightly say Ive ever been lost,
but Ive been mighty perplexed for two or three days runnin'.
Davy Crockett (1786-1836)
To more efficiently and effectively calculate and cut
azimuths while bushwhackinghour after hour, day after dayconsider
one or more of the following ideas, which have proved useful on prior
remote, long-range, multi-day trips, expeditions, and SAR ops.
A high-quality, name-brand baseplate compasssuch
as the Brunton 54 pictured belowis
essential for long-range land nav ops, especially those conducted off
trail. The longer the base, the better.
Suppliers of the Brunton
54 baseplate compass pictured abovewith its one-of-kind optical
sighting mechanism accurate to 0.5 degreesinclude The
Compass Store. NATO tritium (compound 20 mCi) night-vision models
are available from Wellington
Surplus Stores (Australia) and The
Outdoorsman Limited (United Kingdom). More compass manufacturers
Look at this vigorous plant
that lifts its head from the meadow,
see how its leaves are turned to the north,
as true as the magnet;
this is the compass-flower,
that the finger of god
has planted here in the houseless wild,
to direct the traveler's journey.
Henry W. Longfellow (1807-1882),
Baseplate-mounted roamer scales make quick, on-the-go,
calculation or plotting of UTM coordinates very easy. If you don't
have a two-dimensional roamer scale on your baseplate compass, consider
adding one (see annotated photograph below).
Fold pieces of 1/2-wide, white, first-aid tape over
the front edge and the right-hand edge of your baseplate compass (held
in front of you, viewed from above, with the business end pointed
away from you). The tape should be folded equally along the bottom
and top of the compass, and one end of both pieces should meet at
a common corner, the right front corner.
Next, using an indelible marker or write-in-the-rain
pen, lay the top edge of the compass up against the kilometer scale
on your topographic map (you will have to change the scale on your
compass if you use different scale maps on different trips) and simply
transfer the 100-meter hash marks onto the tape on the top side of
your baseplate, starting at the common corner, until you have plotted
1,000 meters worth. Do the same along the right edge of your compass.
Baseplate-mounted map scales make quick, on-the-go,
calculation or plotting of linear distances very easy. If you don't
have a one-dimensional map scale on your baseplate compass, consider
adding one (see annotated photograph above).
Holding the right edge of your compass against the
kilometer scale on your map, continue marking hash marks beyond the
1,000 meter mark that you marked off for the UTM roamer scale above.
Mark as many as you can, hopefully to the 2,000 or 2,500-meter interval.
To make them easier to see, make the 1,000 meter interval tick marks
To keep the hash marks from rubbing off from wear
and tear, sweat, rain, river water, or DEET, cover the 100-meter hash
marks on the first-aid tape with clear scotch tape.
Make sure your compass has a looped lanyard so you
can hang it around your neck, or attach it to a lanyard loop in a
shirt pocket or compass pouch on the shoulder strap of your rucksack
(see annotated photograph above).
It should be long enough so you can hold it comfortably
in your hand while calculating an azimuth on a map or cutting an azimuth
in the bush. The lanyard should be long enough so you can quickly
stow it in a secure but easily accessible locationwithout unfastening
the lanyardto prevent damage while bushwhacking or climbing.
Some manufacturer-provided lanyards are a bit short for regular use
while underway in the bush.
If you have scribed fixed index lines at the 45-,
90-, 270-, and 315-degree intercardinal points on the rotating bezel
of your baseplate and wrist compasses, consider refreshing them with
a few coats of red indelible ink from a Sandford Sharpie permanent
If your compass lacks these radius lines, consider
adding them as they are very useful for working laterally around obstaclessuch
as ponds, pocket wetlands, cliffs, private property, etc.that
temporarily block you from cutting an azimuth (see annotated photograph
above). These four index lines will allow you to quickly add or subtract
45 or 90 degrees to or from an azimuth, without doing the math. You'll
simply box the compass needle or compass card under the appropriate
To add index lines to your compass, simply draw four
lines on the rotating bezel of your compass, each emanating from the
common point directly over the jewel movement, which supports the
compass needle or card, and ending at the 45-, 90-, 270-, and 315-degree
intercardinal points along the rim of the compass bezel. If you like
having these index lines on the bezel of your compass, consider scribing
a fine line where each line is located with a sharp scribe. This will
allow you to easily refresh them before each trip, and the fragile
red Sharpie markings will almost always be visible in the fine, scribed
lines, long after the remainder of the line has worn off on long,
If your baseplate compass has a declination adjustment
feature, please zero it out so everyone is passing around the same
azimuths, either uncorrected or manually corrected.
The copyrighted, two-sided, laminated, 3-by-5-inch
NavTool crib card depicted below contains a lot of land nav information
that is useful on many on remote, long-range land nav ops, especially
when doing a lot of technical, off-trail navigation.
If you would like a free NavTool crib card for use
on our next trip, expedition, or SAR op, e-mail
me in advance and I will bring one along for you.
Commercial UTM and LAT/LON plotters are available from
the following vendors:
Mountaineering Equipment Co.
See "map quad tool"
I believe that there is
a subtle magnetism in Nature,
which, if we unconsciously yield to it,
will direct us aright.
Henry David Thoreau (1817-1862),"Walking,"
Atlantic Monthly, June 1862
Rain, mud, river water, wet snow, and DEET are hard
on maps, so consider waterproofing
your maps with a commercial waterproofer (or Thompson's watersealer).
To further protect them in the bush, carry them in heavy-duty, gallon-size,
zip-lock, plastic bags.
Suppliers of AquaSeal®
Map Seal® include Campmor
If your maps do not have the Universal Traverse Mercator
(UTM) grid lines already overlaid on them, consider adding
UTM grid lines to them. We rely heavily on the easting and northing
UTM grid lines for land navigation in the bush. In addition to occasionally
using them to either calculate a UTM coordinate from the map or plot
a GPS-derived UTM coordinate on the map, we use them hour after hour,
day after day for calculating azimuths, measuring route distances,
and pace counting.
If you need your hands free for negotiating thick
bush, using ski poles or walking sticks, or climbing, but still want
to keep an eye on your map, consider bringing a couple of large-diameter
rubber bands as well as a spare one. By folding your zip-lock-bag-protected
map to size, wrapping it around your forearm of choice like a splint,
and then securing it with two rubber bands, you'll be able to keep
one eye on your topo and the other on the azimuth you're cutting while
U.S. Army Ranger pacing beads are handy for measuring
distances while underway in the bush, particularly when dead reckoning
or trying to reconcile the map with the terrain, or vice versa. To learn
more about U.S. Army Ranger pacing beads, click
If you're carrying ranger pacing beads, inventory the
100-meter beads (the lower set of beads) to make sure there are nine
of them. Several commercially-manufactured units come with fragile,
plastic beads, which crack and fall off when handled roughly in the
If you would like a free set of ranger pacing beads
for use on our next trip, expedition, or SAR op, e-mail
me in advance and I will bring along a set for you.
A heavy-duty, hands-free compass with a brush guard
is very handy for cutting azimuths, hour after hour, day after day,
through steep or tangled terrain. While none are commercially available,
it is relatively easy to fabricate one from a conventional, high-quality
Suppliers of the Silva
Explorer 203 Baseplate Compass used to fabricate the Bushwhacker
Wrist Compass pictured and illustrated above include The
Compass Store. More compass manufacturers
Suppliers of the Velcro hook-and-loop and Fastex®
hardware used to fabricate the Bushwacker Wrist Compass include Outdoor
Wilderness Fabrics, Inc. at 1-800-693-7467 and Quest
Outfitters at 1-800-359-6931. More fabric and hardware vendors.
A short pencil (or waterproof pen) is handy for plotting
UTM coordinates on maps as well as annotating them. On complicated routesespecially
when dead reckoninga piece of waterproof paper is handy for recording
azimuths, distances, elapsed times, terrain features, and other field
On SAR op missions, additional paper is often required
for making sketches and recording pertinent data on activities and observations.
Suppliers of Rite-in-the-Rain®
all-weather paper and pens include the Ben
Meadows Company at 1-800-241-6401 and Forestry
Suppliers, Inc. at 1-800-647-5368.
No matter what brand or model of GPS unit you're carrying
in your ruck, make sure it is properly
configured, and don't be surprised if deep gorges, tall cliffs,
heavy rain or snow, deep cold, or thick, double canopy limit its usefulness
Getting some units to lock onto the requisite number
of satellites has been a challenge in the past, which is why we strive
to always know where we are within a few hundred meters by conventional
In certain locations, it may be necessary to emerge
from the bush at a rocky peak, river bank, lakeshore, or open marsh
before a GPS will work properly.
To increase a unit's usefulness on remote, long-range
trips, expeditions, and SAR opsparticularly in deep, arctic coldconsider
equipping it with lithium batteries as they tend to last longer and
are largely unaffected by deep cold, unlike alkaline batteries.
I shall be telling this with
somewhere ages and ages hence;
two roads diverged in a wood,
and II took the one less traveled by,
and that has made all the difference.
Robert Frost (1874-1963),
The Road Not Taken, 1916, stanza 4
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In God's wilderness
lies the hope of the world,
the great, fresh, unblighted,
John Muir, 1838-1914
Alaska Wilderness, 1890
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thank a Teacher;
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thank a Veteran.
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