MILITARY SURVIVAL MANUAL:VOL.2

WATER GENERATOR
REFERENCE:
FM 21-76, Survival, 1992.
Paul Auerbach, Wilderness Medicine, 3rd Edition, 1995
Howard Backer MD, MPH, Field Water Disinfection, 1999
Eric Cudnohoske, Wisconsin Pharmacal Company, 1999
03-8 WSVX.02.03
UNITED STATES MARINE CORPS
Mountain Warfare Training Center
Bridgeport, California 93517-5001
WSVX.02.04
WSVX.02.05
02/06/05
STUDENT HANDOUT
EXPEDIENT SHELTERS AND FIRES
TERMINAL LEARNING OBJECTIVE
(1) In a cold weather mountainous environment, construct shelters, in accordance with
the references. (WSVX.02.04)
(2) In a cold weather mountainous environment, construct fires, in accordance with the
references. (WSVX.02.05)
ENABLING LEARNING OBJECTIVES
(1) Without the aid of reference, list in writing the characteristics of a safe expedient
shelter, in accordance with the references. (WSVX.02.04a)
(2) Without the aid of references, list in writing the hazards to avoid when using natural
shelters, in accordance with the references. (WSVX.02.04b)
(3) Without the aid of references, list in writing man-made snow survival shelters, in
accordance with the references. (WSVX.02.04c)
(4) In a cold weather mountainous environment, list in writing the tactical fire lay, in
accordance with the references. (WSVX.02.05a)
(5) In a cold weather mountainous environment, start a fire using a primitive method, in
accordance with the references. (WSVX.02.05b)
OUTLINE
1. B ASIC CRITERIA FOR SHELTER. (WSVX.02.04a) Any type of shelter, whether it
is a permanent building, tentage, or a survival shelter must meet six basic criteria to be
safe and effective. The goal is you must Prepare For Some Very Hard Days.
a. P rotection From the Elements. The shelter must provide protection from rain, snow,
wind, sun, etc.
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b. F ree from Natural Hazards. Shelters should not be built in areas of avalanche
hazards, under rock fall or “standing dead” trees, which have the potential to fall on
your shelter.
c. S table. Shelters must be constructed to withstand the pressures exerted by severe
weather.
d. V entilation. Ventilation must be maintained, especially if burning fuel for heat. This
prevents the accumulation of carbon monoxide. Ventilation is also needed for carbon
dioxide given off when breathing.
e. H eat Retention. It must have some type of insulation to retain heat, thus preventing
the waste of fuel.
f. D rying Facility. A drying facility must be constructed to dry wet clothes.
2. NATURAL SHELTERS. Natural shelters require less work or time.
a. C aves or Rock Overhangs. Can be modified by laying walls of rocks, logs or
branches across the open sides.
b. H ollow Logs. Can be cleaned or dug out, then enhanced with ponchos, tarps or
parachutes hung across the openings.
c. H azards of Natural Shelters. (WSVX.02.04b)
(1) A nimals. Natural shelters may already be inhabited (i.e. bears, coyotes,
lions, rats, snakes, etc.). Other concerns from animals may be disease from
scat or decaying carcasses.
(2) L ack of Ventilation. Natural shelters may not have adequate ventilation.
Fires may be built inside for heating or cooking but may be uncomfortable or
even dangerous because of the smoke build up.
(3) G as Pockets. Many caves in a mountainous region may have natural gas
pockets in them.
(4) I nstability. Natural shelters may appear stable, but in reality may be a trap
waiting to collapse.
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3. MAN-MADE SHELTERS. (WSV.02.04c)
a. Snow Wall.
b. Snow Cave.
c. Tree-pit Snow Shelter.
d. Snow Trench.
e. A-frame Shelter.
f. Fallen Tree Bivouac.
g. Snow Coffin
4. CONSTRUCTION OF MAN-MADE SHELTERS.
a. C onsiderations.
(1) Group size.
(2) A low silhouette and reduced living area will improve heat retention.
(3) Avoid exposed hilltops, valley floors, moist ground, and avalanche paths.
(4) Create a thermal shelter by applying snow, if available, to roof and sides of
shelter.
(5) Locate in vicinity of fire wood, water, and signaling, if necessary.
(6) How much time and effort is needed to build the shelter?
(7) Can the shelter adequately protect you from the elements?
(8) When in a tactical environment, you must consider the following:
(a) Provide concealment from enemy observation.
(b) Plan escape routes.
b. S now Wall. The snow wall is an extremely expedient shelter for one or two men.
This shelter is constructed when the elements will not afford time to construct a better
shelter.
(1) Basic principles for construction.
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(a) Determine wind direction.
(b) Construct a wall of compacted snow in the shape of a horseshoe to
shield you from the wind. The wall should be at least 3 feet high and as
long as your body.
(c) A poncho or tarp can be attached to the top of the wall with the other
end secured to the ground for added protection. Skis, poles, branches,
and equipment can be used for added stability.
SNOW WALL
c. S now Cave. A snow cave is used to shelter 1-16 men for extended periods of time.
There must be a well-compacted snow base of at least 6 feet to construct.
(1) Basic principles for construction.
(a) Dig down into the snow until the desired tunnel entrance has been
reached. Place all excavated snow on top of the shelter for added
strength.
(b) Cut an entrance opening into the snow approximately 3 feet by 3 feet.
(c) Continue to dig out cave while removing excess snow out of the
entrance. Shape the roof into a dome. If a bluish color appears through
the snow in the roof, stop, there is not enough snow to support the
roof.
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(d) Create a cooking/working self and a sleeping bench inside the shelter.
(e) A ventilation hole should be dug through the roof at a 45-degree angle
above the entrance. A ski pole or branch is left in the hole to mark the
hole and allow clearing should the ventilation hole become clogged. A
pine bough branch can be placed into the outside of the roof above the
hole to aid in keeping the hole clear during falling snow. During the
day and at night there should be an Arctic century posted for safety in
case the cave collapses.
(f) Personnel who are digging will become wet from perspiration while
digging inside the cave. Personnel that are digging should wear a
minimum amount of clothing with a protective layer.
(g) Once the cave has been dug, completely fill in the entrance hole with
snow block. Pack in loose snow between the cracks and allow it to
harden for approximately 2-3 hours, weather dependant. After it has
hardened, cut out a small entrance hole.
(h) Snow caves can be heated by a candle, which will raise the inside
temperature, approximately 2 degrees. If a candle is left burning while
individuals sleep, a fire watch must remain posted to reduce the danger
of asphyxiation. Burning stoves to heat a cave will cause snow to melt
and should be avoided.
(i) Packs, poncho, or snow blocks can be used to block the entrance to the
cave.
SNOW CAVE
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d. T ree-pit Snow Shelter. A tree-pit snow shelter is designed for 1-3 men for short
periods of time. It provides excellent overhead cover and concealment and should be
used for LP/Ops.
(1) Basic principles for construction.
(a) Locate a tree with bushy branches that provides overhead cover.
(b) Dig out the snow around the tree trunk until you reach the depth and
diameter desired, or until you reach the ground.
(c) Find and cut other evergreen boughs. Place them over the top of the pit
for additional concealment. Do not utilize bough from the tree you are
under.
(d) Place evergreen boughs in the bottom of the pit for insulation.
TREE-PIT SHELTER
e. F allen Tree Bivouac. The fallen tree bivouac is an excellent shelter because most of
the work has already been done.
(1) Ensure the tree is stable prior to constructing.
(2) Branches on the underside are cut away making a hollow underneath.
(3) Place additional insulating material to the top and sides of the tree.
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(4) A small fire is built outside of the shelter.
FALLEN TREE BIVOUAC
f. A-Frame Shelter. An A-Frame shelter is constructed for 1-3 individuals. After the
framework is constructed, pine bough/tentage is interwoven onto the frame and snow
is packed onto the outside for insulation.
A-FRAME
g. S now Trench. A snow trench is a short-term shelter used on extremely hard pack
snow and when trees or building materials are not available, (i.e., alpine and glacier
environments). Blocks of snow or ice are cut and placed to build this shelter.
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SNOW TRENCH (FIRST STEP)
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04-8
SNOW TRENCH
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h. S now Coffin. A snow coffin is built for 1-4 men for extended periods of time. It is a
variation of the snow trench and A-frame, which requires at least 4 feet of compacted
snow.
(1) Basic principles for construction.
(a) Dig a trench into the snow approximately 3 feet wide, 8-12 feet long,
and 4 feet deep.
(b) Dig a cold hole into the floor of the trench and sleeping platforms
(coffins) off the sides of the trench.
(c) Cover the top of the trench for added protection with either an A-frame
or poncho/tarp.
SNOW COFFIN
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i. This table can be used as a general guideline to determine which shelter to construct.
SNOW PACK SNOW DEPTH EST. HRS. TO
CONSTRUCT
RECOMMENDED
SHELTER
LOOSE < 2 FEET 2 A-FRAME COMPACTED 4-6 FEET 2-3 SNOW COFFIN COMPACTED > 6 FEET 3 SNOW CAVE
ICED N/A 2-3 SNOW TRENCH
N/A N/A 1-2 FALLEN TREE
N/A > 4 FEET 1-2 TREE-PIT
N/A > 2 FEET 30 MIN SNOW WALL
5. F IRES. Fires fall into two main categories: those built for cooking and those built for
warmth and signaling. The basic steps are the same for both: preparing the fire lay, gathering
fuel, building the fire, and properly extinguishing the fire.
a. P reparing the fire lay. There are two types of fire lays: fire pit and Dakota hole. Fire
pits are probably the most common.
(1) Without a platform in the snow, the fire will sink. Create a platform as
follows:
(a) Lay several green logs side by side for the size of your fire.
(b) Build your fire on top of the platform or,
(c) Dig down to the earth and start fire.
(d) Create a windbreak if possible.
(e) Avoid using wet rocks. Heat acting on the dampness in sandstone,
shale, and stones from streams may cause them to explode.
(2) D akota Hole. (WSV.02.05a) The Dakota Hole is a tactical fire lay. Although
no fire is 100% tactical.
(a) Reduces the signature of the fire by placing it below ground.
(b) By creating a large air draft, the fire will burn with less smoke than the
fire pit.
(c) It is easier to light in high winds.
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DAKATA HOLE
b. G ather Fuel. Many Marines take shortcuts when gathering firewood. Taking a few
extra minutes can mean the difference between ease and frustration when building a
fire.
(1) T inder. Tinder is the initial fuel. It should be fine and dry. Gather a double
handful of tinder for the fire to be built and an extra double handful to be
stored in a dry place for the following morning. Dew can moisten tinder
enough to make lighting the fire difficult. Some examples of tinder are:
(a) Shredded cedar/juniper bark, pine needles.
(b) Slivers shaved from a dry stick.
(c) Natural fibers from equipment supplemented with pine pitch (i.e.,
cotton battle dressing).
(d) Cotton balls and petroleum jelly or Char-cloth.
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DAKATA HOLE
b. G ather Fuel. Many Marines take shortcuts when gathering firewood. Taking a few
extra minutes can mean the difference between ease and frustration when building a
fire.
(1) T inder. Tinder is the initial fuel. It should be fine and dry. Gather a double
handful of tinder for the fire to be built and an extra double handful to be
stored in a dry place for the following morning. Dew can moisten tinder
enough to make lighting the fire difficult. Some examples of tinder are:
(a) Shredded cedar/juniper bark, pine needles.
(b) Slivers shaved from a dry stick.
(c) Natural fibers from equipment supplemented with pine pitch (i.e.,
cotton battle dressing).
(d) Cotton balls and petroleum jelly or Char-cloth.
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(2) K indling. This is the material that is ignited by the tinder that will burn long
enough to ignite the fuel.
(a) Small sticks/twigs pencil-thick up to the thickness of the thumb.
Ensure that they are dry.
(b) Due to a typically large resin content, evergreen limbs often make the
best kindling. They burn hot and fast, but typically do not last long.
(3) F uel Wood. Fuel Wood is used to keep the blaze going long enough to fulfill
its purpose. Ideally, it should burn slow enough to conserve the woodpile,
make plenty of heat, and leave an ample supply of long-lasting coals.
(a) Firewood broken from the dead limbs of standing trees or windfalls
held off the ground will have absorbed less moisture and therefore
should burn easily.
(b) Refrain from cutting down live, green trees.
(c) Softwoods (evergreens and conifers) will burn hot and fast with lots of
smoke and spark, leaving little in the way of coals. Hardwoods (broad
leaf trees) will burn slower with less smoke and leave a good bed of
coals.
(d) Learn the woods indigenous to the area. Birch, dogwood, and maple
are excellent fuels. Osage orange, ironwood, and manzanita, though
difficult to break up, make terrific coals. Aspen and cottonwood burn
clean but leave little coals.
(e) Stack your wood supply close enough to be handy, but far enough from
the flames to be safe. Protect your supply from additional precipitation.
(f) If you happen to go down in an aircraft that has remained intact, a
mixture of gas and oil may be used. Use caution when igniting this
mixture.
c. B uilding the Fire. The type of fire built will be dependent upon its intended use,
either cooking, heating, or signaling.
(1) C ooking Fires. Cooking fires are used to cook food and boil water.
(a) T eepee Fire. The teepee fire is used to produce a concentrated heat
source, primarily for cooking. Once a good supply of coals can be
seen, collapse the teepee and push embers into a compact bed.
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(2) H eating Fires. Heating fires are used to dry clothing and provide a means of
signaling.
(a) P yramid Fire. Pyramid fires are used to produce large amounts of light
and heat, to dry out wet wood, and provide coals for cooking.
TEEPEE FIRE PYRAMID FIRE
d. S tarting Fires. Lighting fires falls into two categories: modern methods and primitive
methods.
(1) M odern Methods. Modern igniters use modern devices we normally think of
to start a fire. Reliance upon these methods may result in failure during a
survival situation. These items may fail when required to serve their purpose.
(a) Matches and Lighters. Ensure you waterproof these items.
(b) Convex Lens. Binocular, camera, telescopic sights, or magnifying lens
are used on bright, sunny days to ignite tender.
(c) Flint and Steel. Some types of flint & steel designs will have a block
of magnesium attached to the device, which can be shaved onto the
tinder prior to igniting. Other designs may have magnesium mixed
into the flint to produce a higher quality of spark.
(2) P rimitive Methods. Primitive fire methods are those developed by early man.
There are numerous techniques that fall into this category. The only method
that will be taught at MCMWTC is the Bow & Drill.
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(3) B ow & Drill. (WSV.02.05b) The technique of starting a fire with a bow &
drill is a true field expedient fire starting method, which requires a piece of
cord and knife from your survival kit to construct. The components of the
bow & drill are bow, drill, socket, fire board, ember patch, and bird’s nest.
(a) B ow. The bow is a resilient, green stick about 3/4 of an inch in
diameter and 30-36 inches in length. The bowstring can be any type of
cord, however, 550 cord works best. Tie the string from one end of the
bow to the other, without any slack.
(b) D rill. The drill should be a straight, seasoned hardwood stick about
1/2 to 3/4 of an inch in diameter and 8 to 12 inches in length. The top
end is tapered to a blunt point to reduce friction generated in the
socket. The bottom end is slightly rounded to fit snugly into the
depression on the fireboard.
(c) S ocket. The socket is an easily grasped stone or piece of hardwood or
bone with a slight depression on one side. Use it to hold the drill in
place and to apply downward pressure.
(d) F ire board. The fireboard is a seasoned softwood which should be 3/4
of an inch thick. Cut a depression 3/4 of an inch from the edge on one
side of the fireboard. Cut a V-shape notch from the edge of the
fireboard into the center of the depression. This notch is designed to
collect and form an ember, which will be used to ignite the tinder.
(e) E mber Patch. The ember patch is made from any type of suitable
material (i.e., leather, aluminum foil, or bark). It is used to catch and
transfer the ember from the fireboard to the bird’s nest.
(f) B irds Nest. The bird’s nest is a double handful of tinder, which will be
made into the shape of a nest. Tinder must be dry and finely shredded
material (i.e., outer bark from juniper/cedar/sage brush or inner bark
from cottonwood/aspen or dry grass/moss). Lay your tinder out in two
equal rows about 4 inches wide and 8-12 inches long. Loosely roll the
first row into a ball and knead the tinder to further break down the
fibers. Place this ball perpendicular onto the second row of tinder and
wrap. Knead the tinder until all fibers of the ball are interwoven. Insert
the drill half way into the ball to form a partial cylinder. This is where
the ember will be placed.
(4) Producing a fire using the bow & drill.
(a) Place the ember patch under the V-shaped notch.
(b) Assume the kneeling position, with the left foot on the fireboard near
the depression.
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(c) Load the bow with the drill. Ensure the drill is between the wood of
the bow and bow string. Place the drill into the depression on the
fireboard. Place the socket on the tapered end of the drill.
(d) Use the left hand to hold the socket while applying downward
pressure.
(e) Use the right hand to grasp the bow. With a smooth sawing motion,
move the bow back and forth to twirl the drill.
(f) Once you have established a smooth motion, smoke will appear. Once
smoke appears, apply more downward pressure and saw the bow
faster.
(g) When a thick layer of smoke has accumulated around the depression,
stop all movement. Remove the bow, drill, and socket from the
fireboard, without moving the fireboard. Carefully remove your left
foot off the fireboard.
(h) Gently tap the fireboard to ensure all of the ember has fallen out of the
V-shaped notch and is lying on the ember patch. Remove the fireboard.
(i) Slowly fan the black powder to solidify it into a glowing ember.
Grasping the ember patch, carefully drop the ember into the cylinder of
the bird’s nest.
(j) Grasp the bird’s nest with the cylinder facing towards you and parallel
to the ground. Gently blow air into the cylinder. As smoke from the
nest becomes thicker, continue to blow air into the cylinder until fire
appears.
(5) Trouble Shooting the Bow & Drill.
(a) The drill will not stay in depression- Apply more downward pressure
and/or increase width/depth of depression.
(b) The drill will not twirl- Lessen the amount of downward pressure
and/or tighten bowstring.
(c) Socket smoking- decrease the amount of downward pressure. Wood
too soft when compared to hardness of drill. Add some lubrication:
animal fat, oil, or grease.
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(d) No smoke- Wood may not be seasoned. Check drill to ensure that it is
straight. Keep left hand locked against left shin while sawing.
(e) Smoke but no ember- V-shaped notch not cut into center of the
depression or not enough heat generated.
(f) Bowstring runs up and down drill- Use a locked right arm when
sawing. Check drill to ensure that it is straight. Ensure bowstring runs
over the top of the left boot.
(g) Birds nest will not ignite- Tinder not dry. Nest woven too tight. Tinder
not kneaded enough. Blowing too hard (ember will fracture).
e. E xtinguishing the Fire. The fire must be properly extinguished. This is
accomplished by using the drown, stir, and feel method.
(1) D rown the fire by pouring at water in the fire lay.
(2) S tir the ember bed to ensure that the fire is completely out.
(3) Check the bed of your fire by feeling for any hot spots.
(4) If any hot spots are found, start the process all over again.
REFERENCE:
1. FM 21-76, Survival, 1992.
2. Chris Janowski, A Manual that could save you life, 1996.
3. John Wiseman, SAS Survival Guide, 1993.
4. AFP 36-2246, Aircrew Survival, 1996.
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