Cold Weather Survival
5 - Movement
I. PROBLEMS AFFECTING MOVEMENT
Muscular fitness has two
components: muscular strength and muscular endurance. Muscular strength is the
greatest amount of force a muscle or muscle group can exert in a single effort.
Muscular endurance is the ability of a muscle or muscle group to do repeated contractions
against a less-thanmaximum resistance for a given time. Although muscular endurance
and strength are separate fitness components, they are closely related. Progressively
working against resistance will produce gains in both of these components.
5-2. Influence of Seasonal Changes in Weather and Terrain on Mobility
a. Spring Breakup and Fall Freezeup
(1) The spring breakup and fall
freezeup periods are by far the most difficult seasons in which to maintain mobility.
The period of breakup may last from 3 to 6 weeks and will present restrictions
to movement (fig. 5-1). The snow becomes slush and will support little weight.
Winter roads break down, the ice in waterways melts, rivers are swollen and become
torrents. Movement at this time of year poses many problems, however, movement
is possible in cold areas at all times. Normally, at this time of year, temperatures
drop at night, freezing the surface, and mobility during this period can be maintained.
During the day caution should be exercised in shady areas as they may contain
ice and snow even though daytime temperatures are above freezing.
(2) The period
of freezeup with rain and open or half-frozen waterways will also present barriers
to movement. Complete freezeup may take up to 3
months, often restricting the
movement of heavy equipment across lakes until late January.
(3) The early
winter period, when there is little snow and the ground and waterways are firmly
frozen, will provide excellent trafficability for foot soldiers and vehicles.
Winter. The low temperatures, snow, blustery winds, and bulky clothing and
equipment required during winter hinder movement as it is known in more temperate
climates. By the proper use of specialized equipment for cold weather operations,
mobility can be maintained. Using skis, snowshoes, oversnow vehicles, and aircraft,
mobility is possible. In the barren tundra or on icecaps the hard snow found in
these areas will readily support an individual on foot as well as oversnow vehicles.
In the forested areas the snow will normally be deeper and the temperatures lower.
The depth of the snow and the trees in these areas will prove to be the greatest
obstacles to mobility. With oversnow equipment such as skis and snowshoes, properly
trained, equipped, motivated and conditioned troops can maintain mobility.
Forested Areas. A great portion of the North is covered with evergreen forests
and with numerous swamps and water courses. Few trails exist through the forests
and those that do exist are of poor construction, making progress difficult and
slow. The numerous waterways, once they become frozen, will normally provide excellent
routes for foot and some vehicle movement. Whenever possible they should be used
to the maximum for the ease of movement they offer.
II. FOOT MOVEMENT
Winter cross-country travel in the North
is difficult and complex. Of necessity, travel will be slower, However, with the
proper training in the use and maintenance of equipment, the proper enthusiastic
leadership, and the will to accomplish the mission, nothing is impossible.
Basic Rules for Foot Movement
The following guides are based on experience
factors and should be considered in preparing for cross-country movements in the
a. Insure that all personnel participating in the move
are fully aware of the mission, route, etc. Equipment must be checked and loads
evenly distributed. Dispatch trailbreaking teams far enough in advance to insure
continuous, uninterrupted movement of the main body. Men should be dressed as
lightly as possible consistent with the weather to reduce excessive perspiring
and subsequent chilling. Complete cold weather uniforms must be available while
operating in cold environments. A large proportion of cold weather casualties
result from too few clothes being available to individuals at such time as a severe
change in the weather occurs. Therefore, unit clothing discipline must be enforced
consistent with prevailing weather.
b. The first halt after initiating
a march should be made in approximately 15 minutes. This will allow adjustment
of clothing and equipment. Subsequent halts should be frequent and of short duration
to insure rest and to prevent chilling. Halts should, so far as possible, be made
in sheltered places which will provide protection from the elements. Warm drinks
should be provided during the march if possible.
c. The buddy system
is mandatory in the North and men must be instructed to watch their buddy carefully
for early signs of frostbite. Individuals must not be allowed to fall out of the
line of march, except in an extreme emergency. If this should occur, proper care
must be taken to insure that he does not become a cold weather casualty. Normally,
the second-in-command will bring up the rear of the column and, in each halt,
will check the men and report their condition to the leader.
detailed reconnaissance is most important to insure successful mobility in the
northern areas. Maps may or may not exist and those that do exist may not always
be accurate. In planning a move, maximum advantage must be taken of map studies,
aerial photographs, ground and aerial reconnaissance. Without detailed reconnaissance
and prior planning, unit movement may be slowed or stopped by long detours or
e. Marching in single file is often the best formation. It
maintains track discipline, camouflage, and reduces the number of trailbreakers
and reconnaissance parties required. Natural obstacles may limit the use of other
formations. Large units in single file however, become excessively long and will
be slow to react to enemy action to the front or rear. Tactical considerations
will often require the use of other formations. The double track of vehicles
be used as pathways for foot troops, but will rarely afford ease of movement for
ski or snowshoe mounted troops.
(1) The purpose
of trailbreaking is to make the march of the main body as easy and fast as possible
in order that the troops will arrive at their destination
in good fighting
condition. Trailbreaking accomplished at any time of the day or night through
deep snow and difficult terrain is hard and timeconsuming
work. The progress
of trailbreaking is dependent on the terrain, weather and snow conditions, vegetation,
physical condition of the trailbreaking detachment and, finally, on the tactical
situation. Therefore, plans must be carefully made and trailbreaking parties well
(2) In addition to trailbreaking, the mission of providing frontal
security for the main body is a normal function of the trailbreaking party. Approximately
of a unit is given the mission of trailbreaking and frontal security for the march,
for example, the battalion normally assigns one rifle company this mission. The
quartering party may accompany the trailbreaking party or may follow later. The
company in turn assigns one rifle platoon to lead, functioning simultaneously
as a trailbreaking party for the lead company. Since the trailbreaking unit is
the first to arrive in the new bivouac area, its commander is also responsible
for establishing temporary security of the area. When the quartering party arrives
in the bivouac area they will perform the normal functions of a quartering party
as outlined in FM 7–20.
b. Planning. Based upon an estimate of the tactical
situation, terrain, weather and snow conditions, the most suitable route is selected
for the movement. As a general rule terrain features which offer least resistance
will be followed. In selecting a route, consideration must be given to all of
(1) Open terrain. In order to keep the main body sufficiently
dispersed, ski trails are more widely separated in open terrain. For concealment,
normally one ski trail is broken across open terrain. When possible the trail
is broken close to the edge of the forest so shadows will help conceal the trail
and troops moving over it. In open terrain light tracked vehicles should be used
for breaking trail and for towing the trailbreaking party by skijoring to the
maximum extent to save time and energy of the individuals. At times it may be
desirable to break additional trails to expedite troop movement across open areas.
Covered terrain. Whenever possible, time and situation permitting, the
trail should follow along forest terrain with little or no underbrush. It provides
good concealment and protection against wind. The trail should be broken close
to bushy trees in orderto provide better concealment. Thickets and windfall forest
areas should be avoided, as it requires a great amount of effort to break a trail
in areas of this type. If a triple trail is broken for sleds, wide curves must
be made when changing direction and the bushes and branches must be cut from the
inside of the curve. The thoroughness with which the small trees, bushes, and
branches on both sides of the broken trail are cleared will depend on the time
allowed the trailbreaking party.
(3) Hilly and mountainous terrain.
When the situation permits, valleys will most often provide the easiest route.
Frozen rivers frequently afford the easiest route in this type of terrain. If
the valleys cannot be used, the trail may be broken on the lee side of the ridge
line or hill mass that dominates the valley. Care must be exercised to detect
avalanche snow conditions and bypass these areas as necessary. Use gentle inclines
when climbing uphill or descending.
When trails are broken downhill the speed
of the trailbreaking party is often slow,
because of soft and deep snow. However, when packed, the same trails may make
the speed of the skiers in the main body too fast. This will result in many falls,
especially during darkness.
(4) Water routes. Frozen lakes, rivers,
and creeks offer the most suitable routes for the trails. They also help in land
navigation. For best protection and concealment, the trailbreaking party skis
very close to the shore or on the bank, as this facilitates better concealment
of the individuals and units, their trail, and any quick movements into the wooded
areas of the shore. Sometimes in winter, and especially in the spring, there may
be water under the snow surface on surfaces on the lakes and rivers, thus causing
the running surfaces of the skis to freeze. Check for concealed water under the
snow before starting to break trail across the ice. Areas in which water is found
under snow should be bypassed. If this is not possible, the crossing site must
reinforced with snow or with a combination of brush and snow. Also, the
thickness of the ice must be carefully checked before using any ice route. The
minimum thickness of ice for one rifleman on skis is 5 cm (2") ; for an infantry
column in single file on foot, 10 cm (4") ; and for the single light artillery
piece or 1/4-ton truck, 4 x 4, 20 cm (8"). See load bearing capacity tables
in FM 31–71. Warm water springs are prevalent in northern areas of operations
and create a hazard to both foot and vehicle movement. Many of these springs do
not freeze, even in extremely low temperatures, and may cause streams to have
little or no ice and some lakes to have only thin ice. Their presence in muskeg
or tundra areas can cause weak spots in otherwise trafficable terrain. These areas
should be either bridged, reinforced, or bypassed.
(5) Obstacles. Since
even minor obstacles retard the march, they are bypassed whenever possible. If
a wide obstacle is met, such as a ridge or a steep
riverbank, several trails
are broken over the obstacle so that the main body can cross it on a broad front.
Trees and brush are cut well below the bottom of ski tracks in order to avoid
twigs and branches entangling in ski bindings and tow ropes. Obstructions such
as fences may be cut in order to allow the skier to pass through.
and snow condition. In early winter there is more snow in open terrain than
in dense forest; therefore, the trail should be broken close to the forest edge.
In late winter the reverse is true. In early spring more snow can be found in
ditches, ravines, and on the shadowy side of hills. Maximum advantage should be
taken for movement during periods of reduced visibility, such as snowstorms. These
storms will conceal movement and at times completely camouflage the trail after
the unit has moved over it. Care should be exercised to preclude moving directly
into a strong wind. Movement in the same direction of the wind usually requires
much less effort. Under the most adverse conditions, navigation will also become
extremely difficult. Trails may become covered very quickly after being broken,
requiring the distance between the trailbreaking unit and the main body to be
conditions such as driving snowstorms will slow the movement
but will facilitate security.
(7) Darkness. Skiing and snowshoeing at
night is slow and exhausting. Therefore, the trail for a night march must be broken
along the easiest terrain
available. Avoid all rough terrain if possible. Navigation
of the trailbreaking party demands special skill in darkness and during periods
visibility. Rivers, creeks, ridge lines, and forest boundaries should
be used as aids to navigation in spite of the fact that the broken trail might
become longer. Because of the darkness it may be necessary to leave guides posted
at locations where the main body may take the wrong course.
(8) Enemy activity.
When breaking trail within the frontline area, the requirements for concealment
are most important. Therefore, the trailbreaking party is forced to ski along
covered terrain whenever possible. However, if the mission requires fast movement,
a trail is broken along the shortest course, paying less attention to concealment.
The security mission normally given the trailbreaking unit will take on added
importance and may require more support for this unit.
(b) These responsibilities
affect the course of trail. In frontline areas the trail should be broken along
terrain features which facilitate observation and deployment of the main body.
Also, the route should follow terrain which offers a sound approach and suitable
places fortemporary defense. Sometimes it is necessary to check critical terrain
features located near the trail before the trailbreaking party movesforward. Elements
of the trailbreaking party may occupy certain security positions and remain stationary
until the main body has passed these critical points, at which time they may rejoin
the rear of the column. For the purpose of deceiving the enemy, it may be desirable
to create numerous false trails crisscrossing and angling off in all directions.
In burned-over areas or thin deciduous forests, concealment from aerial observation
is practically impossible. A single trail clearly indicates the whereabouts and
approximate size of the unit making it. Miscellaneous trails, therefore, create
confusion. Of course, the breaking of false trails is time consuming and
also acquaint the enemy to the fact that a sizable unit was required for the amount
of work accomplished.
(9) Number of trails used. The number of trails
to be broken depends upon the size of the column using them, the tactical situation,
and time available for trailbreaking. An organization of battalion size normally
requires two or more march trails and one or more communication trails for messenger
service and control of the march column. In cases where time is very limited for
preparations, only one trail may be established for a battalion. When contact
with the enemy becomes imminent, greater emphasis is placed on security and less
emphasis placed on trailbreaking. The possibility for a rapid deployment of the
troops requires that the number of trails or tracks be increased from that of
a routine cross-country march.
c. Organization. The trailbreaking party
preceding units mounted on skis should also be mounted on skis. The trailbreakers
of elements on snowshoes should also be mounted on snowshoes. Mixing of skiers
and snowshoes on the same track is not recommended. Snowshoes tend to compact
the snow on ski trails making it difficult for the main body to follow on skis.
The lead company normally will be assigned the mission of breaking trail for one
complete day. It is replaced by another company on the following morning. One
rifle platoon at a time is assigned as lead platoon and is called a Trailbreaking
Party. It may also include engineers whose duties would include reconnoitering
ice routes, seeking suitable terrain for permanent type winter roads, preparing
ice reinforcements, and performing other engineer tasks. Forward observers may
also accompany the trailbreaking party.
(2) Depending on terrain conditions,
1 to 2 oversnow vehicles, when available, should be assigned to the party to be
used for breaking trail in open terrain, skijoring, and carrying individual loads
and platoon equipment. In unfavorable terrain conditions the vehicles remain under
company control or with the higher echelon. The trailbreaking party consists of
its organic rifle squads, called Trailbreaking Squads. A trailbreaking party is
expected to break trail approximately a half a day at a time, but may be rotated
sooner depending on local conditions. Trailbreaking squads, in turn, are normally
rotated as often as necessary in order to maintain the speed necessary to complete
the mission in time.
d. Trailbreaking Squad. The organization, duties,
and special equipment of the trailbreaking squad are indicated in figure 5-2.
Squad leaders must insure that their men have a suficient number of tools of proper
size before moving out. The tools are part of the tent group equipment and are
used in preference to entrenching tools. To conserve energy and toassure an uninterrupted
march, the leading man (breaker) of the squad is regularly relieved.
deep and heavy snow a relief may become necessary every 150 meters (150 yds).
When the change is ordered by the team leader, the man to be relieved steps sideways
out of the path and falls in at the rear of the team. The man following him then
becomes the breaker. Special equipment is exchanged by passing it to the next
man in line during the rotation. The breaking team will be relieved by the reserve
team as directed by the squad leader whenever the point team tends to slow down
due to fatigue.e. Trailbreaking Party. The trailbreaking party consists
of two or more trailbreaking squads. Normally a rifle platoon will be assigned
this mission, especially if the snow is heavy and the weather severe.
of the squads is always designated as the base squad and is responsible for navigation
and the general direction to be followed. The platoon leader and the navigation
detail directly under his control will follow the base squad. When deadreckoning
is required, the base squad breaks the center trail and works slightly ahead of
the other squads for the purpose of maintaining the proper direction of the squads
which are moving on both sides of the track made by the base squad (fig. 5-3).
In cases where the party follows easily recognizable terrain features, such as
small creeks or the edge of open terrain, the base squad follows next to this
terrain feature, making navigation easier. The other squads are echeloned to the
right or left, and their breaker (the first man) to the right or left of the last
man of the squad ahead (fig. 5-4).
Interval between the trails varies from about 15 meters (15 yds) in covered terrain
to approximately 100 meters (100 yds) in open areas, depending
on the local
situation. The depth of the party varies from 100 to 200 meters (100 to 200 yds).
Members of the weapons squad may be assigned to the navigation detail, to flank
security missions, to assist the vehicles in breaking their trail off the ski
trails, and similar duties. The weapons squad may follow and improve the trails
being established, as directed by the leader of the trailbreaking party. From
the area where vehicles are temporarily halted due to
the close proximity of
the enemy, one track may be widened into a triple track to facilitate the movement
of heavy weapons, ammunition, and warming tents. This equipment is usually moved
forward by man-drawn sleds.
(3) The trailbreaking party moves far enough ahead
of the column to permit a steady rate of march by the main body. This distance
varies according to the tactical situation, snow, weather conditions, and terrain
encountered. For covered movements through territory controlled by friendly troops,
the trailbreaking party normally precedes the main body by 1 hour for each 5 km
(3 miles) of marching distance. For example, if a 25 km (15 miles) march
planned, the trailbreakers leave 5 hours in advance of the parent unit. For uncovered
moves, the trailbreakers precede the main body by a distance
dictated by the
f. Techniques. The trailbreaking squad may break
a normal or triple track as required. On normal track the first man makes his
tracks so that the grooves are a little wider apart than usual, approximately
30 cm (1'). The trailbreaker usually uses the one step technique. In deep and
soft snow, however, his
steps will be shorter than normal and he will be forced
to lift his skis at each step to prevent the tips from running under the surface
of the snow. Progress will be slow and may be exhausting. Therefore, the man in
the breaker position must be rotated often.
(1) When track-laying vehicles
and cargo sleds cannot be used any further due to the tactical situation, the
crew-served weapons, ammunition and warming tents must be moved to the units in
man-drawn sleds. Therefore a triple track is broken because the normal trail is
too narrow. When starting a triple trail (1, fig. 5-5), the leading three men
of the breaking team will break a normal trail of two grooves. The third groove
is started by the fourth man who keeps one ski in the already broken groove and
makes a new groove with his left (right) ski, depending on which side of the original
groove the new track will be broken. Alternate men behind the fourth man, both
in breaking and reserve teams, ski along the original tracks made by the first
three leading men, the others following the tracks made by the fourth man. This
creates a trail with three tracks, a triple trail (2, fig.5-5). This provides
proper type of trail for pulling mandrawn sleds. Due to the fact that sleds
tend to destroy the ski trails, only one of the ski trails will be prepared as
a triple trail and this trail will be used for man-drawn sleds only.
trails must be kept separate from the trails and roads established for vehicles
and cargo sleds, due to the fact that the vehicles tend to destroy
trails and, conversely, the skiers on the winter road tend to harass the vehicular
traffic. Signal wire layed alongside the ski trail must be located far enough
to the side so as not to become entangled with skis and ski poles. When crossing
the ski trail the wire must be buried well below the trail or secured overhead,
whichever is most desirable.
Marking the Trails
a. The trailbreaking squad marks its trails
as uniformly as possible. The types of markings used must be known to the unit
that follows. When several squads are operating, marking by the base squad is
usually sufficient. The marking is simple, and recognizable by night as well as
by day. Temporary trails through new snow need simple markings only where the
trails or roads are crossed by other trails. Trails that are frequently used for
long periods are more permanently marked. The following can be used as trailmarkers:
Twigs on trees and shrubs broken in a predetermined manner, or blazes (nicks)
in tree trunks made by using a hatchet or machete.
(2) Poles or guiding arrows
planted in the snow.
(3) Markers made of rags or colored paper.
b. Snowfalls, fog, poor observation, and uniformity
of the terrain necessitate thorough and frequent markers spaced at uniform intervals
and numbered successively in the direction of march. To avoid the destruction
of trailmarkers by traffic, the markers are placed about 1 meter (3') off the
trail. When strange tracks cross the trail of the unit they are obliterated at
the point of crossing. Guides are posted at crossings, if necessary, to direct
units that follow.
Continue to Land Navigation