FM 5-15 (1944)

Collection

Survival, Water, Medical Field Manuals

Case

Military Manuals

Download PDF ↗ Live URL (may be dead)

Document text

WAR DEPARTMENT FIELD MANUAL

CORPS OF ENGINEERS

WAR DEPARTMENT FIELD MANUAL
FM 5-15

$
This manual supersedes ЕМ 5-15, Í October 1949, including C 1, 2 April 1941, and
C 2, 10 December 1941; and so murh of Training Circular No, 52, War Department,
1942, as pertains to FM 5-15; Training Circular Мо. 96, War Department, 1983,

CORPS OF ENGINEERS

FIELD
FORTIFICATIONS

WAR DEPARTMENT - 14 FEBRUARY 1944

United States Government Printing Office
Washington : 1944

WAR DEPARTMENT,
WASHINGTON 25, D. C., 14 February 1944.

FM 5-15, Corps of Engineers Field Manual, Field
Fortifieations, is published for the informatión and
guidance of all concerned.

fA. G. 300.7 (16 Jun 43).]
By ORDER ОЕ THE SECRETARY or War:

G. C. MARSHALL,
Chief of Staff.

OFFICIAL:

J. А. ULIO,

Major General,
The Adjutant General.

DISTRIBUTION :

B and H 1, 2, 4, 6, 7, 17, 44 (4) ; R 1-4, 6, 7, 17, 18,

44 (5); Bn and H 5, 19 (5); C 5 (10).
(For explanation of symbols see FM 21-6.)

CONTENTS

Paragraphs
CHAPTER 1. GENERAL. ............. 1-2
CHAPTER 2. TERRAIN EVALUA-
TION.
Section І. General._-__-.-.--...-------- 3-9
II. Aids to the study of terrain... 10-11
111. Tactical study of terrain... 12-17

CHAPTER 3. GENERAL FORTIFI-
CATION TECHNIQUE.
Section J. Tools and materials... 2... 18-19
11. General technique... ....-... 20-27

CHAPTER 4. ENTRENCHMENTS
AND EMPLACEMENTS. :

Section I. General___._-.-.-------..---- 28-29
11. Infantry entrenchments for
hasty fortifications.........- 30-36
111. Infantry weapon emplace-
Melts. oc али шок ве та 87-46

IV. Special and standard trench... 47-48
V. Field artillery emplacements... 49-57
VI. Antiaircraft artillery emplace-

meni. lot а 58-65
CHAPTER 5. SHELTERS.

Section I. Сепета1__—-------------------- 66-72
II. Surface shelter8 2 Lec 2l 13-74
ПТ. Cut-and-cover shelters... -- ~ 15-76
IV. Cave shelters... .. -_------- 77-92
APPENDIX І, Glossary of ћегппв_____.-_----_--_--

П. Effects of bombs and projec-
ES 1-3

ИТ. Concrete machine-gun em-
placement....... Е 1-4

IV. 40-mm Antiaireraft tower-... 1-3

Page
1

0-0

26
28

102

126
156
165
181
221

224
229

236
269

This manual supersedes FM 5-15, 1 October 1940, including 0 1,
This manual superscdes ЕМ 5—15, 1 October 1910, including € 1,
Circular Хо, 52, War Department, 1942, ag pertains {о ЕМ5-15,

CHAPTER 1
GENERAL

1. PURPOSE AND SCOPE. Troops in occupied posi-
tions increase their combat effectiveness by works of
an engineering nature called field fortifications. This
manual describes field fortification methods and gives
details of construction of entrenchments, emplacements,
and shelters. It also outlines the principles of terrain
appreciation which apply to field fortifications, and ex-
plains how to combine individual field fortifications
into a unified system by means of organization of the
ground. It does not cover the subject of obstacles, which
is treated in FM 5-30.

2. CLASSIFICATION AND USE OF FIELD FORTI.
FICATIONS. а. Classification. There are two general
classes of field fortifications.

(1) Hasty fortifications. Those initially con-
structed when in contact with the enemy or when con-
tact isimminent. They consist generally of light clear-
ing of fields of fire, foxholes for personnel, open weapon
emplacements, hasty antitank and antipersonnel mine
fields, barbed-wire entanglements, strengthening of
natural obstacles, observation posts, and camouflage.

(2) Deliberate fortifications. Those constructed
out of contact with the enemy, or developed gradually

from hasty fortifications. They include deliberate en-
trenchments, antitank and antipersonnel mine fields,
antitank obstacles, covered weapon emplacements,
barbed-wire entanglements, troop shelters which are
proof against artillery fire and weather, extensive signal
cemmunication systems, gasproof inclosures of com-
mand posts and aid stations, and elaborate camouflage.

b. Use. Field fortifications increase the combat ef-
ficiency of troops. They must be used skillfully to
further the mission of a unit, and must not be allowed
to lead to a passive or static defense. The decisions as
to whether or not to occupy a position and the degree of
fortification to undertake are primarily tactical and
beyond the scope of this manual.

CHAPTER 2
TERRAIN EVALUATION

SECTION I
GENERAL

3. PURPOSE. The purpose of this chapter 18 to de-
scribe the means of evaluating terrain. For a detailed
discussion of the effect of terrain on tactical disposi-
tions and for information on organization of the ground,
see FM 100-5, 7-10, 7-15, 7-20, and 1—40.

4. DEFINITIONS. a. Terrain, from a military view-
point, is an area of ground considered in relation to
its use for military purposes.

b. Terrain evaluation is the analysis of the area of
probable military operations, to determine the effect
of the terrain on the lines of action open to opposing
forces in the area, |

5. INFLUENCE OF TERRAIN. а. The character of
the area or region of military operations often has a
decisive influence upon the course of operations. The
more important factors to be considered in evaluating
terraiu include not only natural features, such as ridges,

streams, bodies of water, woods, and open spaces, but
- also such features as roads, railways, and towns.

b. Ground forms, such as a succession of ridges and
valleys, influence military operations by aiding or
hampering the movement of military forces. An ad-
vance parallel to the ridges and valleys is mechanically
easier than movement across successive ridges.

€. The salient feature of а commander's plan of
action are usually determined so as to take full advan-
tage of favorable terrain features.

6. TERRAIN FACTORS. Regardless of the type of
terrain and the tactical situation, terrain always can be
evaluated in terms of the following five factors: obser-
vation, fields of fire, concealment and cover, obstacles, .
and communications.

a. Observation. Observation of the ground on
which a fight is taking place is essential in order to
bring effective fire to bear upon the enemy. Observa-
tion also aids in increasing the effectiveness of fire
directed оп an enemy stopped by obstacles. Тһе value
of cover and eoncealment is based on denial of obser-
vation to the enemy. Observation also affords infor-
mation as to what both enemy and friendly troops are
doing, making it possible for the commander to control
more effectively the operations of his troops.

b. Fields of fire. Fields of fire are essential to the
defense, An ideal field of fire for infantry is an open
stretch of ground in which the enemy can be seen and
in which he has no protection from fire as far as the
limits of effective range of the infantry weapons.
Fields of fire can be improved by cutting or burning
weeds, grass, and crops; clearing brush and trees; de-
molishing buildings; and cutting lanes through woods,

However, concealment must be carefully considered in
all such work. The time and labor available for this
type of improvement should be considered in evaluat-
ing the terrain.

с. Concealment and cover. Concealment from
view, both from the air and ground, will usually pro-
tect military personnel and installations only as long
as the enemy is unaware of their location. Unconcealed
installations and troops invite destruction. Cover in-
cludes protection from fire, either that provided by
the terrain, or that provided by other natural or arti-
ficial means.

d. Obstacles. Obstacles are obstructions to the
movement of military forces. Some of the common
natural obstacles of military value are mountains,
rivers, streams, bodies of water, marshes, gullies, steep
inclines, and heavily wooded terrain. Proper evalua-
tion of natural obstacles permits the most effective use
of artificial obstacles.

(1) Mountains parallel to the direction of advance
of a force limit or prohibit lateral movement and pro-
tect the flanks; perpendicular to the advance, they are
an obstacle to the attacker and an aid to the defender.

(2) Rivers are similar to mountains in their effect
on forces moving parallel and perpendicular to them.
Rivers flowing parallel to the advance may be used
as routes of supply.

(3) Marshes frequently provide more delay to an
advance than bodies of water, because generally it is
more diffieult to build causeways than bridges. Mech-
anized vehicles can be restricted in movement by dense
woods, marshes, steep inclines, gullies, stumps, large
rocks, and bodies of water.

е. Communications. Communications consist of

roads, railroads, waterways, airways, and their facili-
ties. They are important to both offense and defense
for moving troops and supplies. In most situations,
especially in the operations of large bodies of troops,
the means of communication are of vital importance.
The existing ones generally must be studied thorough-
ly and utilized to the maximum before new ones are
constructed. |

7. OBJECTIVES. Terrain objectives, normally, are
clearly defined features, the capture of which will in-
sure the defeat of a hostile force, or from which the
operation can be continued or the success exploited.
Terrain objectives, in the attack by ground forces, usu-
ally are located in, or in rear of, the hostile artillery
area, One may be a terrain feature affording command
observation, another a critical point in the hostile com-
mand system or on essential supply routes, and another
an obstacle to armored forces. In some situations the
objective is clearly indicated by the mission; in others
16.13 deduced from the situation.

8. MAPS AND RECONNAISSANCE. Maps are the
basis for terrain studies but should be checked by air
reconnaissance, air photographs, and ground recon-
naissance. Works of man, especially routes of com-
типісабіоп, are changing constantly; and even natural
ground forms may change.

9. CORRIDORS. Features such as ridges, streams,
woods, roads, and towns divide all terrain into more
or less separate areas. Such an area frequently consists
of a valley lying between two ridges or an open space
between two wooded areas. The limiting features pre-

vent direct fire or ground observation into the area;
they may be high or low, continuous or discontinuous.
When the longer axis of such an area extends in the
direction of movement of a force, or leads toward or into
a position, the area is called a corridor,

SECTION II
AIDS TO THE STUDY OF
TERRAIN

10. GENERAL. Maps and aerial photographs, sup-
plemented by ground and air reconnaissance, form the
basis for studying terrain. In many cases maps marked
in special ways simplify its study. Often a series of
special maps, on each of which is emphasized a separate
item of military importance such as roads, streams, or
ridges, is necessary. The purpose of this section is to
indicate methods used in preparing such maps.

11. FEATURES OF MILITARY IMPORTANCE. a.
Ground forms. Drainage lines and ridge lines are the
natural basis for studying terrain with respect to the
shape of the ground, Drainage lines always form a
connected system or systems of branching lines, Ridge
lines form similar systems of branching lines, То-
gether, ridge and drainage lines form two interlocking
branching systems which, singly or together, clearly in-
: dicate the general shape of the ground.

(1) Figures 1 @ shows a section of a contoured map.
Figure 1 @ is the same map with the drainage lines em-
phasized. This is generally done in blue. Figure 1 (3)

(D Section of eontoured map before emphasis.

Figare 1.

@ Drainage lines emphasized,

Figure i—Continued.

Ро
(2 Drainage and ridge lines emphasized.

Figure 1—Continued.

(5) 600- and 700-foot contour lines emphasized.

Figure 1— Continued

УЛ
№
Хо
КУ М

Т
W
1

те SN T NN X ЕЕ КЕШЕ
ə.
22 оо
| х NANI
om

700 FT

С} BELOW 640 ЕТ
@ Different elevations emphasized by shading.
Figure 1—Continued

5663979 —44——2 x

emphasizes the ridge lines. Usually this is done in
brown ог red. Figure 1 (4) shows the drainage and
ridge lines emphasized on the same map. The more pro-
nounced ridge and drainage lines are given special em-
phasis by marking them more heavily.

(2) In figure 1 ( the 600- and 700-foot contours are
emphasized with a heavy line. In figure 1 (б the
ground having an elevation over 640 feet has been indi-
cated by hght shading; ground with elevation over 700
feet, by darker shading; and ground with elevation
under 640 feet is unshaded, Elevations on а contoured
map frequently are emphasized by using a separate tint
or color for each range of elevation, to make ground
forms and commanding elevations more apparent.

(3) Figure 2 (1) shows a section of a photomap, and
figure 2 (2) shows the same map after the drainage lines
have been emphasized. ` Usually, unless they are em-
phasized, it is quite difficult to follow the minor drain-
age lines on an aerial photograph or photomap. How-
ever, by stereoscopic examination of suitably overlap-
ping aerial photographs, the minor drainage or ridge
lines easily may be distinguished.

(4) Figure 3 (1) shows a section of an uncontoured
map. Although no contours are shown, a fairly accu-
rate visual picture of the actual shape of the terrain
may be had by interpolating ridge lines halfway be-
tween drainage lines, as shown in figure 8 (2). In general,
шаш ridges divide principal drainage systems. There-
fore, the approximate location of important ridge lines
usually can be determined, even though actual elevations
ате not known.

b. Roads. Figure 3 (3) emphasizes roads. Roads of
different classification or type can be indicated by dif-
ferent colors, Кога division, a map of this nature is

@ Section of photomap.

Figure 2.

С) Section of photomap with drainage lines emphasized.
Figure 2—Continued.

E
ЗЭС oat КЫ,

[ / ys M
x Ж Ек
PEL

(TA

5 Aim wa ,
ak

| Ч کد‎
E b = 2
DATTA

кава а

Figure 8—Continu

often used to emphasize all roads which are able to carry
the division loads.

c. Railroads. Figure 8() emphasizes railroads.
Numbers indicate siding capacities and circles indicate
yards. . |

d. Bridges. Figure 30) emphasizes rivers and
bridges with their capacities.

e. Other features of military importance. Other
features of military шірогбапсе, such as natural re-
sources and water resources, may be emphasized on spe-
cial maps in a manner similar to that used for roads,
railroads, and bridges.

SECTION Ш
TACTICAL STUDY OF TERRAIN

12. PURPOSE. Evaluation of the terrain is an im-
portaut element in every tactical operation. Its tac-
tical study may be mental, oral, or written, depending
upon circumstances. It may be made by the com-
mander himself, ог by any subordinate designated by
him. |

13. LIMITING CONSIDERATIONS. Тһе terrain
studied should include all of the area involved in the
contemplated operation. The details of the study are
affected by other considerations. А commander mak-
ing a tactical study of the terrain is limited by his
mission and by his own and the enemy's capabilities.
G-3, in preparing details of a tactical study of the
terrain, is limited by the capabilities of his own force

and by the commander's decision or directive for the
operation; G-2 usually is limited by the enemy's
capabilities. Тһе specialist, such as the tank com-
mander, the artillery commander, the chemical officer,
or the engineer, will find his study Jimited by the powers
and limitations of his arm or service.

14, GENERAL TOPOGRAPHY. Any deductions
made as to the tactical effects of the terrain must be
based on a knowledge of the topographical features of
the area under consideration. Тһе following usually
should be considered:

a. Drainage system. Streams and valleys are of
particular importance because, together with the inter-
vening ridges, they make up the general framework
of the terrain.

b. Ridge system. This is the complement of the
drainage system and should be approached in the same
manner. А

с. Routes of communication. Тһе road net avail-
able for tactical maneuver or supply, the presence or
absence of rail facilities, navigable waters, and airplane
landing facilities, all come under this subhead.

d. General nature of the terrain. АП the fore-
going information is summarized briefly in а final
paragraph.

15. MILITARY ASPECTS OF TERRAIN. The facts
upon which further conclusions are based having been,
stated, the study now proceeds to the evaluation and
interpretation of these from the military point of view.
At this point the study resembles an intelligence study,
an operations study, or both. As a means of systemati-
zation, the area is divided for purposes of discussion

into natural subareas; or, if there are no distinctive
natural boundaries, into subareas delimited with regard
to the tactical situation. Within each subarea, terrain
elements affecting the military situation are consid-
егей; where applicable, each element is considered both
from the enemy's viewpoint, and from our own.

16. CRITICAL TERRAIN FEATURES. Asa result
of the study just indicated it frequently becomes clear
that a certain terrain feature, for example a dominant
hill or ridge, or an obstacle to mechanized attack, will
be critical iu the contemplated operation, or that its
possession by either the enemy or by our own forces will
have a marked influence upon the operations of either
side. If there is such a terrain feature, it should be
discussed briefly at this point; if there 18 not, a state-
ment to that effect should be made.

17. TACTICAL EFFECT OF TERRAIN. This por-
tion of the study should summarize the effect of the
terrain on the immediate tactieal or administrative
situation. Using a systematic approach, frequently it
is desirable to discuss separately the effect of the terrain
upon each enemy eapability, and then to discuss in a
similar manner its effect upon each line of action
contemplated by our own troops.

CHAPTER 3
GENERAL FORTIFICATION
TECHNIQUE

SECTION I
TOOLS AND MATERIALS

18. TOOLS. Tools normally used for hasty fortifica-
tion work are carried by the infantry. These may be
supplemented by additional tools obtained from en-

WIRE CUTTERS SHOVEL

Figure 4. Entrenching tools carried by infantry soldiers.

PACKED IN CARRYING CASE

FOLDED FOR CARRYING

fOR USE AS A PICK

FOR USE AS A SHOVEL

e
Figure 4—Continued.

gineer supplies. Each infantry soldier carries à small
entrenching tool (fig. 4) on his pack. Standard-sized

tools are supplied in infantry entrenching tool sets
(figs. 5).

4 CROWBARS

r Î
— чо |} | | 26 AXES
250 D-HANDLED
SHOVELS

125 PICK МАТТОСК5

9 WIRE CUTTERS

2 MAULS

ААА ААА ААА Ал АЛАЛЫ ААА АДАЛ АА,
(3

SCALE 3FT.

po UU
Figure 5. Principal tools carried in infantry entrenching tool set.
19, MATERIALS. Materials for fortification are sup-
plied through engineer dumps, and include antiperson-
nel mines and firing devices, lumber, barbed wire and
pickets, and materials for reveting, camouflage, shelter
construction, and concrete construction. Antitank
mines are supplied like ammunition.

SECTION II

GENERAL TECHNIQUE

20. CLEARING FIELDS OF FIRE. Suitable fields
of fire are required in front of each entrenchment or :

26 SAWS

emplacement. In clearing them the following princi-
ples must be observed :

a. Do not disclose position by excessive or careless
clearing (fig. 6).

b. In areas organized for close defense, start clear-
ing near main line of resistance and work forward at
least 100 yards.

с. In all cases leave a thin natural screen бо hide de-
fense positions (fig. 7).

d. In sparsely wooded areas, remove the lower
branches of scattered, large trees. Occasionally 16:15
desirable бо remove entire trees which might be used ав
reference points for епешу fire.

e. In heavy woods, complete elearing of the field of
fire is neither possible nor desirable, Restrict work to
thinning undergrowth and renioving lower branches
of large trees. In addition, clear narrow lanes for fire
of automatic weapons (fig. 8).

f. Remove or thin thick brush. It is never a suitable
obstacle and obstructs the field of fire.

g. Demolish other obstructions to fire, such as build-
ings and walls, only when resulting debris provides
less enenry protection.

h. Mow grain crops and hay fields or, if ripe and
dry, burn them if it will not disclose the position.
Usually this is practicable only for a deliberate position
organized prior to contact with the enemy.

i. Drag away cut brush to points where it will not
furnish concealment to the enemy nor disclose the
position. I

j. Before clearing the fields of fire make a careful
estimate as to how much clearing сап be done in the
time available. This estimate often determines the
nature and extent of the clearing to be undertaken, since

ORIGINAL TERRAIN

ARS

RIGHT - AFTER PROPER CLEARING

Figure 6. Clearing fields of fire.

566397 *-—44———83

EN RIGHT
(JUST BEHIND THIN NATURAL SCREEN)

Figure 7. Thin natural sereen,

'вподвом одешојпв 101 e1g Jo SIULI Sutrtə[O 78 AMAA

аолу ЛИМ AW3N3 'G3AON38 LON
$14830 “ӨМНҮЗЛО HONW 001-9МОНА

гж
QN — k

репиппод--4 940814
Ф
“435:34н05 AW3N3 'Q3AOW3H 3913 30 ЗМЛМ
111934|31 S33H1 ONY н5пнанзома A INO — 1H91U

a field of fire only partially cleared may afford the
enemy better concealment and cover than the area in
its natural state, Estimates may be based on table I,
which makes no allowance for the removal of debris.
Additional allowance must be made for this, depending
upon the amount of debris, length of haul, and equip-
ment available,

TABLE Г. Man-hours required to clear 100 square yards -

4 A Man-hours
Description of clearing Tools used . required
Medium clearing—clearing under- | Saws, axes__ зи

growth and some trees not exceed-
ing 12 inches in diameter.

Light clearing—-clearing small brush | Ахе8------- 1%
only.

21. CAMOUFLAGE. Concealinent is of prime impor-
tance in locating defensive works. Before any exca-
vation is started, all turf, sod, leaves, or forest humus
is removed carefully from both the area to be excavated
and that on which spoil is to be piled. This material is
set aside and replaced over the spoil when the work
is completed. ‘To prevent discovery of the work during
excavation, camouflage nets are suspended from stakes
or trees before excavation is started, The workers con-
fine their activities to the area beneath the camouflage
net, The net is suspended high enough above the
ground to permit excavation without snagging equip-
ment or entrenching tools on it. After the excavation
has been conipleted and the spoil covered with sod or
other natural camouflage material, the net is lowered
close to the ground so that it is inconspicuous from
ground observation. Nets are kept in position when
the weapon is not being fired. Arrangements are made

to withdraw or lift the net during action. For a more
complete discussion of camouflage, see КМ: 5-20.

22. EXCAVATION. Excavation is usually by pick
and shovel. The nature of the soil, tools available,
condition and experience of men, presence of the enemy,
amount: of light to work by, size of excavation, and
weather conditions, all affect the rate of excavation.
Because of the large number of variables involved,
precise data cannot be given. Аз а rough guide, it may
be stated that in medium soil, using standard size
tools, a mam in good condition can excavate between 20
and 30 cubic feet per hour. Table II gives estimates
for excavation of man-hours required to build the
various types of infantry weapons emplacements de-
scribed in chapter 4.

Тавів II. Excavation and camouflage data for infantry weapons

emplacements
Б Man-

N ours re-

Weapon Туре ої om- в 3 Pon m ашке

placement* flaged (cubic struet in

(feet) feet) medium
soil

Rifle... su e Foxhole..... 10x 10 37 1%

Automatic те. _______ засобу 10 x 10 37 15
N 125 1

Rocket launcher_______ Pit-foxhole „| 10x 10 | 287 414
қ Ртб па 5х 5 50 8
Machine gun, light, са]. || Horseshoe. ..| 15х15 | 123 7
.80. 2-foxhole....| 12х 12 74 8
Machine gun, heavy, |[Horseshoe...| 15 x 18 140 8
cal. .30. {3 foxhole....| 15 х 15 111 5
60-mm. mortar........ Ріф l. Дала си 14 х 14 70 4
81-mm. шог аг... ао 16 х 16 108 6
Circular... 21x21 110 5
37-mm. AT gun........ FARS 29 x 29 195 10
Rectangular | 27х36 | 550 | 28
57-mm. АТ gun........ Fan......... 24 х 89 410 21
105-mm. howitzer M3__! Cireular..... 29 х29 430 22

“866 chapter 4 for details of emplacements. 1 Without foxholes. ? With foxholes»

23. DISPOSAL OF SPOIL. Excavated soil is much
lighter in color and tone than surface soil and must be
hidden carefully lest its presence disclose the fortifica-

М 22 И 20 f A
4 2 а

С
юэ?!
“хүү, =

SPOIL BEING CONCEALED CORRECTLY
Figure 9. Disposal of spoil.

tion (fig. 9). There are several ways to dispose of spoil.
a. It may be used to form a parapet if the topsoil is
carefully saved and used to cover the parapet. Turf,

sod, leaves, or other litter from under nearby bushes or
trees are used to make the parapet resemble its surround-
ings.

b. It may be removed and carefully hidden under
trees or bushes or in ravines, Care must be taken to
avoid revealing tracks.

с. It may be collected and used, partly camouflaged,

to form parapets for dummy positions,
24. DRAINAGE. Lack of proper drainage increases
the maintenance work and the hardships of the troops
occuping the fortifications. It must be provided for in
the lay-out and construction of all works.

a. Proper location. Proper location Jimits but does
not eliminate the drainage problem. If possible, low
points and drainage lines are avoided, and trenches are
located on slopes (fig. 10). A slope of 1 percent causes
all water to run to the lowest part of trench, from which
it can be easily drained., Slopes exceeding 214 percent
cause erosion.

b. Surface and rain water. Surface and rain water
сап be largely excluded by deflecting it through the use
of small ridges (fig. 10) into ditches passed around the
fortification, or over it by means of flumes,

e. Subsurface water. Surface water may be re-
moved by the use of sumps or of drainage ditches (fig.
10) run to natural drainage lines from low points in en-
trenchments or emplacements. Sumps are located at
low points and emptied by bailing, siphoning, or pump-
ing. They should be à minimum of 115 feet square and
1 foot deep.

25. REVETMENTS, A revetment is a retaining
wall, or facing, for maintaining an earth slope at an

"зЯвцтвар 201 рајеоој Арлодола цэчэхт, ‘OT әл

нда MOVIVHS

HON3H1 NIH31VM 30
Й мола 40 м01453 9

HON3ML QHVONYLS

ної
е

GN3931

"HON3H1 ONhOuv

u3lv4 зОуанп5 19314
—3 01 3015 MO1NO 43114
7169$ ним нома MOTIYHS

мола / 39vNIVHO

но ЗИП OL
HOLIG зоумума

angle steeper than its natural angle of repose. In all
but the hardest ground, when the position 15 to be oc-
cupied for more than a few days, some measures must
be taken to prevent crumbling of walls. Decreasing the
slope for this purpose also decreases protection afforded
by the emplacement and makes concealment more diffi-
cult. Revetments require considerable labor and mate-
rial, but reduce maintenance and insure stability. Earth
walls in entrenchments and emplacements not only are
subject to normal erosion processes and wear and teur
of constant occupation, but also must withstand heavy
earth shock caused by explosion of bombs and artillery
shells. "There are two kinds of revetment, the retain-
ing-wall type and the surface or facing type.

a. Retaining-wall type. This typo is self-support-
ing and acts by its weight. Dimensions of the excava-
tion must be increased to allow space for this type of re-
vetment,

(1) Sandbag revetment. These are particularly
useful for emergency work, for repairs, and on the
interior slopes of earth parapets,

(a) The standard sandbag measures 14 by 2614
inches when empty, aud has a string attached 3 inches
from the top. When three-fourths full, the bag weighs
from 40 to 75 pounds, depending upon nature and
moisture content of the filler, The average filled sand-
bag weighs about 65 pounds, and occupies a space 434
by 10 by 19 inches. The following data are useful in
estimating the number of sandbags required for reveting
purposes :

1. If a single row of stretchers is used, as occa-
sionally is done for small revetments,
about 160 sandbags are required for each
100 square feet of surface to be reveted.

2. If alternate headers and stretchers are used,
as is proper, about 320 sandbags are ге;

quired for each 100 square feet of surface
to be reveted,

SECTION ELEVATION SECTION ELEVATION

CHOKES AND SIDE SEAMS OUT CHOKES AND SIDE SEAMS IN
(WRONG) (RIGHT)

ELEVATION ELEVATION
JOINTS NOT BROKEN JOINTS BROKEN
(WRONG) (RIGHT )

ых >
SECTION ELEVATION SECTION ELEVATION
ALL STRETCHERS STRETCHERS AND HEADERS
(WRONG) (RIGHT)

Figure 11. Sandbag revetment,

3. If sandbags are used for fills, parapets, or
breastworks, about 195 are required for
each 100 cubic feet of fill.

(b) Ordinary sandbags should be used for tempo-
rary reveting only. Where bags are to be in place for
a month or longer under average conditions of moisture,
they must be rotproofed or filled with soil partially

stabilized with cement or bitumen. The latter method
usually is simpler in the field.

(e) Sandbags are laid as follows (fig. 11):

. Fill bags uniformly about three-fourths full.

. Tuck in bottom corners of bag after filling.

. Build walls with slope 3 on 1 to 4 on 1.

. Place bags perpendicular to slope.

. Place bottom row headers.

. Alternate intermediate rows as headers and
stretchers.

- Complete with a top row of headers.

. Place side seams and choked ends on the inside.

. Вгеак joints and beat bags into place aud
into rectangular shape with back of shovel,
or tamp with feet.

(2) Sod revetment. Thick sod makes durable re-
vetments, Sods are cut about 18 by 9 inches, laid grass
down, except for top layer, and pinned together with
wooden pegs. The procedure given for sandbag
revetment applies.

b. Surface or facing revetment. Surface or facing
revetment must he supported, and serves mainly to pro-
tect the reveted surface from effects of weather and
damage due to occupation. When strongly constructed,
it retains loose material. Its top should be about 8
inches below the ground level to prevent its being
snapped or damaged if tanks cross the reveted wall.

(1) Issue material. Issue material, such as burlap
and chicken wire, wire mesh, expanded metal (ХРМ),
or corrugated iron, for this type of revetment may be
obtained in limited quantities at engineer dumps.
These materials are held in place against the surface
to be reveted either by wooden pickets (at least 3
inches in diameter) or by issue steel pickets. Pickets

Оу Set. зн

5 бо ~

are driven into the floor and held at the top by hold-
fasts. In installing this буре of reveting (fig. 12), the
following operations are necessary :

(a) Cut grooves for pickets into wall to be re-
veted, Space 114 to 6 feet apart, depending upon re-
veting material to be used.

(b) Prepare holdfast in front of each groove.
Hold fast anchor picket should be from 8 to 10 feet
from wall.

Figure 12. Installing burlap und chicken-wire revetment.

(d) Drive all pickets at least 114 feet into floor and
fasten tops to anchor pickets with two turns of No. 10
wire, Draw pickets tight by racking. Pickets draw
material tight against surface to be reveted.

(2) Natural material. Since issue material often
is difficult to obtain in the field, most reveting is done

with natural material such as brush and cut timber
obtained at the site.

(а) A brushwood hurdle (fig. 13) 15 a woven revet-
ment unit usually 6 feet long and of required height.
Brushwood less than 1 inch in diameter at butt is woven
on a framework of sharpened pickets driven into the
ground at 18-inch intervals. When finished, hurdle is

ғ. сыз
б Жо
Gir SUN

Figure 13. Building а brushwood hurdle.

removed and carried to erection site where pickets are
driven into floor and held in place by holdfasts.

(b) Continuous brush revetment (fig. 14) is con-
structed by driving 3-inch pickets at 1-pace intervals
about 4 inches from face of surface to be reveted.
Space behind the pickets then is packed with small,
straight brush laid horizontally. Pickets are drawn
tight by means of holdfasts.

БАТЫН ЛЭ
Rr

Figure 14. Continuous brush revetment.

PARAPET
STRUTS

“ОЛ ا‎
GROUND UNE
IN MEDIUM SOFT SOIL

LOWER PIT ONLY WILL
REQUIRE REVETMENT

Figure 15. Cut-timber revetment.

natural means of reveting foxholes and emplacements.
16 is similar to continuous brush revetment, except that
a horizontal layer of small timbers, cut to length of
wall to be reveted, is used in place of brush. Pickets

ENEMY
—

LON I$ SLOPE

GROUND
LINE

ENEMY

— a

ION I$ SLOPE

GROUND
LINE

4" MIN. DIAMETER ANCHOR
LOG POST ` STAKE

Figure 16. Breustworks (height varies).

are held in place by holdfasts or struts. When avail-
able dimension lumber may be used in a similar
manner.

26. BREASTWORKS AND PARAPETS. Breast- |
works and parapets are built for protection when soil
conditions or subsurface water prevent excavation.
They also are used with dug-in emplacements to save
extra digging. They are built at least 3 feet thick at the
top to protect against caliber .30 bullets and against
shell fragments. Also, they should be free of loose
rocks and pieces of wood. Fignre 16 illustrates various
types of breastworks.

27. PROTECTION AGAINST TANKS. So far as
practicable, entrenchments and emplacements are built
to provide protection against tanks. Rocks or other
pieces of hard material should not be left on or near the
surface of the ground within 3 or 4 feet of the lip of the
entrenchment or emplacement. "Гһе pressure on such а
rock caused by a tank collapses earth walls which other-
wise would be able to withstand the passage.

26639744 — 4 45

CHAPTER 4
ENTRENCHMENTS AND
EMPLACEMENTS

SECTION I
GENERAL

28. EMPLOYMENT. a. It must become a habit of all
soldiers to seek protection from enemy fire, advantage
being taken of natural cover such as ditches or holes
in the ground. Whenever the situation becomes sta-
bilized temporarily, they dig entrenchments for them-
selves and emplacements for their weapons. This ар-
plies to crews of all weapons; personnel guarding road
blocks, bridges, rear installations, and tactical head-
quarters ; and troops in bivouac or assembly areas.

b. In all defensive situations troops are trained to
strengthen their positions and seek protection by the
immediate construction of hasty field fortifications.

c. In the attack troops are trained to drive forward
until the objective is captured and consolidated, taking
full advantage of all existing cover. Positive measures
are taken to insure that the momentum of attack 15 main-
tained. А change from the offensive to the defensive is
a responsibility of command and is justified only when
necessary to avoid ruinous losses.

29. REQUIREMENTS. Entrenchments and emplace-
ments must meet the following requirements:

a. Permit each individual or weapon crew to accom-
plish the assigned fire mission.

b. Ве simple and easily constructed.

e. Provide maximum protection with minimum time
and labor.

d. Provide all-around defense.

e. Afford maximum concealment.

f. Provide protection against mechanized attack.

SECTION II
INFANTRY ENTRENCHMENTS
FOR HASTY FORTIFICATIONS

30. GENERAL. Entrenchments are located to cover
a selected area with fire and, at the same time, provide
concealment from aerial and ground observation and
protection from enemy fire. These requirements are
met when the troops are located in one- or two-man fox-
holes as described in this manual To confuse the
enemy, judicious use must be made of decoys or dummy
positions.

31. FOXHOLES. а, General. Foxholes are entrench-
ments normally dug for individual protection when con-
tact with the enemy is imminent or in progress. They
provide excellent protection against small-arms fire, ar-
tillery shell fragments, airplane fire or bombing, and
the crushing action of tanks. Тһе one- and two-man
foxholes are basic ty pes, the choice of type resting with

the squad leader if not prescribed by higher authority.
The two-man foxhole is used when men must work in
pairs or when, for psychological reasons, battlefield com-
radeship is desirable.

b. Use. For units within the battle position, fox-.
holes are sited with the longer side generally parallel
to the front, but they are distributed around weapon em-
placements to provide for all-around defense. "Troops
occupy their foxholes only when an attack is imminent
ог т progress. In some situations, where the need for
rest is paramount, commanders may permit soldiers to
stop excavation before full depth has been reached.

32. ONE-MAN FOXHOLE (fig. 17). a. Dimensions.
(1) The size and shape of the foxhole are affected by
the following:

(a) It is as small as practicable, to present the mini-
` mum target to enemy fire.

(b) Itis wide enough to accommodate the shoulders
of a man sitting on the firestep.

(с) It is lorg enough to permit the use of large-size
entrenching tools.

(d) It is at least 4 feet deep to the firestep, from
which the standing occupant should be able to fire.

(e) А sump is dug in one end for bailing out water
and for the feet of the seated occupant.

(2) The foregoing cousiderations result in the di-
mensions shown in figure 17. The soldier should mem-
orize these simple dimensions: 2 feet wide, 314 feet long,
4 to 5 feet deep depending upon the height of the man,
and additional depth at one end for the sump.

b. Details of construction, In most types of soil
the foxhole gives positive protection against the crush-
ing action of tanks, provided the soldier crouches at least

SPOIL FROM EXCAVATION
USEO TO CONSTRUCT ALL-
AROUND PARAPET.

GROUND LINE

МА 4 to ЕК
DEPENDING ON
HEIGHT OF MAN

SECTION

Figure 17. One-man foxhole, (Camouflage omitted.)

2 feet below the ground surface (fig. 18). In very sandy
or very soft soils i& may be necessary to revet the sides
to prevent caving in. Тһе spoil is piled around the
hole as a parapet, 3 feet thick and approximately 15 foot

MINIMUM 2 FEET CLEARANCE
REQUIRED TO РВОТЕСТ` AGAINST
TANK TRACKS

MINIMUM
CLEARANCE
2 FEET

Figure 18. One-man foxhole protects against tanks,

high, leaving a berm or shelf wide enough for the soldier
to rest his elbows upon while firing. If turf or topsoil
is to be used to camouflage this parapet, the soldier first
removes the topsoil from an area 10 feet square and sets
it aside until the foxhole 1s completed.

с. Foxhole with camouflage cover. It may be
practicable for the soldier to vemove the spoil to an in-
conspicuous place and to improvise a camouflage cover
for his foxhole (fig. 19). "This technique is especially
effective against a mechanized attack supported by foot
soldiers, Riflemen remain concealed until the tanks
have overrun the position ; then they rise up and combat
the enemy foot soldiers following the tanks.

VITANDA

W |

ЭМ ылы уулт 5 BEN x p
DETAIL OF CAMOUFLAGED X: quf y Ies
COVER cu S С.
Ф

Figure 19. One-man foxhole with camouflaged cover.

33. TWO-MAN FOXHOLE (fig. 20). The two-man
foxhole consists essentially of two adjacent one-man
foxholes. Since it is longer than the one-man type,
the two-man foxhole offers somewhat less protection
against tanks crossing along the long axis, as well as
against airplane strafing and bombing and artillery
shell fragments, Figure 15 shows a two-man foxhole
revetted in soft or sandy soil. |

34. INDIVIDUAL PRONE SHELTER. Prone shel-
ters (fig. 21) seldom are dug m forward areas. They
may be authorized in rear areas when ground attack is
unlikely, or when the warning service insures sufficient
time to constrüct foxholes. The prone shelter, being
shallow, does пої provide protection against the crush-

2
==

ONE "MAN
FOXHOLE

(9 Figure 19— Continued,

ing action of tanks and is no£ suitable asa firing position.
The prone shelter gives considerable protection against
hostile artillery and aviation and against small-arms
fire.

35. CONNECTING TRENCHES, Connecting trenches
(fig. 22) are conspicious to aerial observers and on

aerial photographs, and thus reveal the defensive dis-
positions. Continuous connecting trenches are not dug
asa normal procedure. When two forces are in contact
and dispositions have been revealed beyond any ques-

SPOIL FROM EXCAVATION
"USED TO CONSTRUCT ALL~
AROUND PARAPET

ENEMY

Ё
roce
ТҮНТ

ИША

Figure 20. Two-man foxhole. (Camouflage omitted.)

tion, a few short trenches may be dug in inconspicious
places to permit necessary daylight movement across
exposed areas, Necessary connecting trenches also may
be dug in close country, such as jungle, where the posi-

tion probably will not be disclosed. Further, they шау
be dug whenever the improved protection, control, com-
munications, and supply outweigh the sacrifice of con-
cealment.

36. OBSERVATION POSTS. Wien observers are lo-
cated in exposed positions, they should be well protected
and concealed.

PARAPET `

Nan REST

4105 FT. 1
DEPENDING ON
HEIGHT OF MAN М

SECTION
6) Figure 20—Continued.

a. Both the one-man foxhole (fig. 17) and the two-
man foxhole (fig. 20) with camouflaged cover (fig. 19)
are suitable for use as observation posts.

b. The covered observation post (fig. 93), although
a good type, takes considerable time to build. Since
the overhead cover provides splinterproof protection
only, this type of observation post is valuable only when
well concealed. It requires 21 cubic feet of excavation
per foot of length, or a total of 105 cubic feet per 5-foot
section.

МЭХ
РАВАРЕТ

SPOIL USED FOR РАВАРЕТ
Figure 22. Shallow connecting trench. (Camouflage omitted.)

11804 цог) длөв40 ределогу “gz AMNA
МА 1УМ011235-55082 мула

HONSYL
SONVYLNS

зоумуча

303 dWfis u3Au3580

#05 1У36

И ИУ

SSVNIVHO
403 40105

HL9N31 ми 2;

S901 ма NIN >

< — P
эмп ампонз °
пунпіум

NO VAu3sgO
ноз SNIN3dO

59980МУ5

SECTION III
INFANTRY WEAPON
EMPLACEMENTS

37. GENERAL, Because of their advanced positions,
infantry weapons such as machine guns, antitank guns,
mortars, and cannon generally require emplacements for
the protection of weapons and crews, and foxholes to
protect personnel not sheltered in the emplacement.
Careful attention is paid to camouflaging emplacements
against both ground and aerial observation, Dummy
emplacements are constructed for deception. (See
table II for an estimate of the man-hours required to
dig the emplacements described in this section.)

38. AUTOMATIC RIFLE. The automatic rifle is
fired from а one-man foxhole and does not require
special emplacement.

39. CALIBER .30 MACHINE GUN (LIGHT). "There
are two types of emplacements for this gun: the horse-
shoe type and the two-foxhole type.

a. Horseshoe type (fig. 25). (1) The gun is placed
in firing position ready for immediate action. Lying
down, if exposed to fire, the crew first excavate about
15 foot beneath the gun and then a similar depth for
themselves, thus making an open shallow pit (fig. 24).
The spoil is piled around in a parapet.

(2) The emplacement 18 completed by digging out
а horseshoe-shaped trench, about 2 feet wide, along the
rear and sides of the pit, leaving a chest-high shelf to the
center and front to serve as a gun platform (fig. 25).

PARAPET— ^

"о
:DEPTH -BELOW GROUND LINE:
LIGHT MG — ABOUT № FT.
HEAVY MG— 110 1 k, FT.
Figure 24. Initial stage in horseshoe type emplacement for cali-

ber .80 machine gun (light or heavy). (Camouflage omitted.)

BERM ABOUT IFT.

Чиг!

PARAPET ЗЕТ. THICK /
` ALL AROUND 4 `

WIDE
INCDUS

SECTION
Figure 25. Horseshoe type emplacement for caliber .30 machine

gun (light).

—
UN PLATFORM
3$FT. WIDE-

(Camoufluge omitted.)

The spoil is piled around the emplacement to form a
parapet at least 3 feet thick and low enough to permit
all-around fire.

(3) This emplacement furnishes protection against
small-arms fire and shell or bomb fragments. In firm
soil this emplacement offers protection against the
crushing action of tanks. In loose soil, logs about 8
inches in diameter, placed across front, rear, and sides
of the emplacement and embedded flush with the top of
the ground, help to make the emplacement resistant to
the crushing action of tanks. When tanks appear about
to overrun the position, the gunners pull the weapon to
the bottom of the treuch at the rear of the emplacement
and then crouch down to either side.

b. Two-foxhole type (fig. 26). This emplacement
consists of two one-man foxholes close to the gun posi-
tion. To lay it out, a short mark is scratched on the
ground in the principal direction of fire. On the right
of this mark a foxhole is dug for the gunner. On the
left of the mark and 2 feet to the front, another foxhole
is dug for the assistant gunner. The spoil is piled all
around the position to form a parapet, care being taken
to pile it so as to permit all-around fire of the weapon.
In firm soil, the two-foxhole type provides protection
for the crew and the weapon against the crushing action
of tanks. When tanks appear about to overrun the ро-
sition, the gun is removed from the tripod and taken
into one foxhole, the tripod into the other. The gunner
and assistant gunner crouch in the holes.

e. Choice of type. Аза firing position, the two-
foxhole type is a little less flexible than the horseshoe
type, but it is easier to construct and more nearly tank-
proof than the horseshoe type. Therefore, the two-fox-
hole type generally is preferred.

40. CALIBER .30 MACHINE GUN (HEAVY). Тһеге
are two types of combat emplacements for this gun: the
horseshoe type and the three-foxhole type. In addition,

PRINCIPAL SPOIL FROM FOXHOLES
DIRECTION USED FOR ALL- AROUND
PARAPET

OF FIRE
‹ v

prO AS

й хэс
GUN PLACED HERE ЭЭ охнО.Ё. POR"
TO FIRE TO REAR У GUNNER ”

Figure 26. Two-foxhole type emplacement for caliber .80 machine
gun (light). (Camouflage omitted.)

there is an antiaircraft type for use when the gun is
mounted on elevator for fire against air targets,

a. Horseshoe type (fig. 27). This emplacement is
similar to the one described for the light gun (par. 39).

866397? —44 ———5 61

The open shallow pit for the heavy gun (fig. 24) is
dug somewhat deeper, from 1 to 114 feet below ground
level. Construction procedure is the same. This em-
placement permits easy traverse of the gun through
180°. То fire aimed shots to the rear, the gunner must
get out of the trench and sit on the forward part ої:
the gun platform. In most types of soil, tanks can run
over this emplacement without destroying it, the

: Apes

- gest

Figure 26—Continued.

“weapon, or the occupants. In loose soil, logs about 8
inches in diameter placed across the front, rear, and
sides of the emplacement and embedded flush with
the top ої the ground help to make it tankproof. Upon
the approach of tanks, the crew, without dismounting
the weapon from the tripod, move it to the rear into
the horseshoe trench and then crouch down to either
side. .

b. Three-foxhole type (fig. 28). The tripod legs
for the heavy machine gun are reversed when the

WC вааз уар?
СУ Y. , | Е Zp,
Fie sre 47002 wd

З. GUN PLATFORM
‚ WAIST HIGH

. у=

192

КОД: 27. К 4 ` <

uif РА Pa a 1 Е У Ы

m EUM Ч Ян. mri M Ч M 5 TRENCH ABOUT

777! dit мон ОГ 3FT. WIDE

ЕТ —
PLAN

SECTION

Figure 27. Horseshoe-type emplacement for caliber ,30 machine
gun (heavy). Camouflage omitted.

weapon is fired from the three-foxhole emplacement,
This allows the gun to be mounted close to the gunner's
foxhole, which is immediately behind the weapoh.
The assistant gunner occupies the foxhole to the left.
The third foxhole remains unoccupied until it becomes
necessary to fire the gun to the left, at which time the

See
1 о“ ` ENEMY ° Й
19 $ d

` FOXHOLE

TRIPOD ОҒ GUN
зт. 18 REVERSED

Ж yet

КҮ
т E

“PARAPET: ЗЕТ THICK Ч ~
ALL AROUND’

Mala T

Figure 28. Three-foxhole type emplacement for caliber 30
machine gun (heavy). Camouflage omitted.

gunner and the assistant gunner shift to the right
(couterclockwise). The spoil is piled all around the
emplacement to form a parapet, care being taken to
pile it so as to permit all-around fire of the weapon.
When tanks appear about to overrun the position, the
gun is dismounted from the tripod and the tripod is
collapsed. One member of the crew takes the gun with
him into his foxhole; the other takes the tripod.

c. Comparison of combat types. In general, the
horseshoe type and the three-foxhole type of emplace-
ment are both satisfactory. Аза firing position, the
three-foxhole type is less flexible than the horseshoe
type, but in some soils it may be more tankproof. "Тһе
three-foxhole type has the advantage of using standard
foxholes. However, the horseshoe type permits the gun
to be restored more quickly to its firing position follow-
ing а tank attack, since the gun remains on the tripod.
For the latter reason, the horseshoe type generally is
preferred for the heavy machine-gun.

d. Antiaircraft type (fig. 29), The caliber .80 heavy
machine gun, provided with elevator, is emplaced in
а circular pit about 4 feet in diameter at the bottom,
deep enough to provide protection and yet allow the
gun to engage ground targets. It is used only where
defense against air targets is the primary considera-
tion, as it does not provide the protection afforded by
the horseshoe and three-foxhole types.

41. 60-MM MORTAR EMPLACEMENT (fig. 30). a.
Open type. This consists of a rectangular pit large
enough to accommodate the mortar, the gunner, and the
assistant gunner. Тһе emplacement is kept to the mini-
mum size to afford protection against airplane fire and
bombing and against artillery shells, but it allows room
for firing the mortar and storing necessary ammuni-
tion. Тһе front edge 16 sloped so that the aiming stake,
about 10 yards to the front, is visible through the sight
and so the weapon's fire will be clear. "The spoil from
the excavation is piled all around the pit to form a low
parapet. Foxholes for members of the mortar squad
not required at the gun are prepared not far from the
emplacement. Additional ammunition is placed іп
nearby shelters.

SPOIL USED
TO CONSTRUCT
ALL-AROUND

PARAPET

PARAPET GROUND LINE

PROFILE

Figure 29. Antiaircraft emplacement for caliber 30 machine
gun (heavy) with elevator. (Camouflage omitted.)

« N МА
А АГ
` цох
%
`
И
ze
Z
£ ¿

7 EXCAVATION
ABOUT ЗЕТ.
DEEP

NOTE: SPOIL PILED
ALL AROUND AND
GAMOUFLAGED

» ASSISTANT GUNNER

Figure 30. Open emplacement for 60-mm mortar. (Camouflage
omitted.)

b. Two-foxhole type (fig. 31). This shows the 60-
mm. mortar in action with only the base plate dug in,
the crew operating from one-man foxholes. This two-
foxhole type of emplacement is preferred when the mor-
tar is in defilade.

42. 81-MM MORTAR EMPLACEMENT (fig. 32).
Except for somewhat larger dimensions, this emplace-
ment is the same as the open type described above for
the 60-mm mortar. А revetted ammunition niche may
be built into the side of the pit.

43. ROCKET LAUNCHER. There are two types of
emplacement for this weapon, the pit-foxhole type and
the pit type.

а. Pit-foxhole type (fig. 33 (D). This emplacement
is a circular pit, 3 feet in diameter and about 314 feet
deep, large enough for two men. It permits the assist-
ant rocketeer to turn with the traversing weapon, so
that he is never behind it when it is fired. The emplace-
ment is shallow enough to permit the rear end of the
rocket launcher at maximum elevation to be clear of the
parapet, thus insuring that the hot back-blast from the
rockets is not deflected to the occupants. This em-
placement is поб tankproof. "Therefore foxholes for the
crew are dug nearby. As the antitank. mission of this
weapon requires that it be kept in action against hostile
tanks until the last possible moment, these foxholes will
be occupied. only when а tank is about to overrun the
emplacement.

b. Pit type (fig. 33 ©). In firm soil the diameter of
the circular pit (fig. 33 (1)) сап be increased to 4 feet and
an additional circular pit 2 feet deep and 2 feet іп dia-
meter excavated in the center. This leaves a circular

(роугшо әЗенпошес))

чејлош 9101-09 103 149шээс( то ојоцхој

OMT те

опат

е
D — x ~. `
_ ⁄ у FEES
ael a — Z.
ILL
27 PE
EXCAVATIO:

ABOUT 4 ЕТ.

AIMING STAKE ABOUT
10 YARDS TO FRONT

~ У

В------авал ati
SECTION
®

Figure 32. 814001 mortar emplacement. (Camouflage omitted.)

fire step 1 foot wide and about 314 feet below the surface.
When tanks appear about to overrun the position, the
rocketeer- and assistant rocketeer crouch down into the
lower pit. When the tanks have passed, the rocket
launcher quickly is returned to action.

EMPLACEMENT
15 WAIST DEEP

SPOIL. FROM.
, FOXHOLES. B
'EMPLACEMENT

FOXHOLE

FOXHOLE
PLAN
(D Pit-foxhole type.

Figure 83, Emplacements for antitank rocket launcher,
(Camouflage omitted).

€ NOTE:
E З SPOIL
2 REMOVED

SECTION
@ Pit type.
Figure 38— Continued.

44. 37-ММ ANTITANK GUN EMPLACEMENT. For
this weapon there are three standard types of emplace-
ment, each adapted to a special situation. For flat ter-
rain the circular emplacement (fig. 34) is preferred,
since it permits all-around fire. For sloping terrain

FOR BARREL ARE DUG,
WHEN NOT FIRING,GUN

15 PLACED IN THESE
PITS 50 А5ТО BE BELOW
LEVEL OF PARAPET

GUN CLEARS PARAPET
ALL AROUND з! GROUND
PARAPET. Fw] LINE

SECTION
Ф

Figure 34. Circular type emplacement for 87-mm antitank gun.
L (Camouflage omitted.)

the rectangular-pit emplacement with ramp (fig. 85) is
preferred, since it gives partial defilade and protection
against ground observation. When the direction of
enemy approach can be foreseen definitely, as in cover-
ing a road block in a defile, the fan type emplacement
(fig. 36) is preferred, since the gun can be fired instantly
without being moved from the cover position.

Figure 34— Continued.

a. Cireular type emplacement (fig. 34). This em-
placement consists of a circular pit, 11 feet in diameter
and 1 foot deep. measured from ground level, with an
all-around parapet 4 feet wide and approximately 9
inches high. The banks should be sloped so that the
gun can be moved into and out of the emplacement.
Pits for the wheels and a slit in the parapet for the gun
barrel allow the gun to be lowered below the parapet
when not firing, at which time the crew takes cover іп
nearby foxholes, An ammunition pit may be dug in
the center of the emplacement or into the parapet. Ad-
ditional ammunition is placed in nearby shelters. The
gun 15 maneuvered quickly to fire ir any direction by
elevating the barrel, lifting the trails, backing the gun

to the center of the emplacement, turning it in the de-
sired direction, and pushing it forward against the
bank.

b. Rectangular pit type emplacement (fig. 35).
This emplacement consists of a rectangular pit 10%
feet wide, by 14 feet long, and 81% feet deep. То get the
gun into and out of the pit, a ramp is dug either straight
out of the pit or at an angle thereto, depending upon the
Sector of fire assigned to the gun. If the ramp is turned
at an angle to the pit, the elbow is curved so that the
gun can be moved around the corner. 'The gun is
backed into the rectangular pit when not in firing posi-
tion. The spoil is piled alongside the excavation to
form a parapet. Several foxholes may be dug inside
the emplacement without interfering with the move-
ment of the weapon. Additional foxholes are dug
nearby for the remaining members of the gun crew.

e. Fan type emplacement (fig. 36). This type of
emplacement permits little traverse but great speed in
going into action. Тһе ramp is to the rear of the
eniplacement. і

45. 57-MM ANTITANK GUN EMPLACEMENT. Fig-
ure 37 illustrates the basic type of emplacement for this
weapon. lt permits fire through an arc of approxi-
mately 1109, and even more if protection is sacrificed
by modifying the parapet. 'The ramp normally is in
rear of the emplacement, but it may be to the front if
terrain conditions require. The spoil is piled on both
sides of the emplacement to form a parapet approxi-
mately 2% feet high and 3 feet thick. Foxholes for
the gunner and the assistant gunner are dug within the
emplacement. Additional foxholes for other members
of the crew are dug nearby.

х a де сэт,
Pen `
~, ~
%2
:
9
2

@
PERSPECTIVE б й

RAMP
ЕТ: ~ АА К!
6 EN Шылым AL
| зет. MING

FIRING _
POSITION

DEPTH

XM
OOS

“тщ

' — И е 6%
USED TO COVER POSITION

CONSTRUCT
'PARAPET PLAN

Figure 85. Rectangular pit type emplacement for 37-mm anti-
tank gun, (Camouflage omitted.)

E и

3 { їл 457
ATO SPA y e СД ha Y й i
p. Me

| VERIS

v 4 М у 3 4 npa К? 1 h

( “у ЫН. Ani "n MN “н 2 m i
e Ч 1 ҮШ ШЕ ME LM { as ша

ЦЭ ei

SPOIL PILEO TO EXCAVATION
FORM РАВАРЕТ FOR GUN IS
I$ ЕТ. DEEP

PLAN

Figure 36. Fan type emplacement for 37-mm antitank gun.
(Camouflage omitted.)

566397?—44 ——5 77

46. 105-MM HOWITZER M3 EMPLACEMENT. Fig-
ure 88 illustrates a circular emplacement, 19 feet in
diameter, permitting all-around fire. The pit is dug

Figure 37. Fan type emplacement for 57-mm antitank gun. (Cam-
ouflage omitted. Excavation is 2 feet deep.)

about 2 feet deep and the spoil is piled in a low parapet
all around the emplacement. A ramp is dug to the
rear. Foxholes for members of the crew are dug
nearby.

AMMUNITION ;,
SHELTER

Figure 88. Emplacement for 105-mm howitzer МЗ. (Camouflage
omitted.)

SECTION IV

SPECIAL AND STANDARD
TRENCH

47. SPECIAL TRENCH. а. Purpose. To meet the
needs of the field artillery the special trench (fig. 39)
has been developed. Where several men must be pro-
vided protection within a limited area, special trenches
frequently are nsed because they take less space than
foxholes. Because they are especially suitable for use

PLAN OF "ОНЕУВОМ” PLAN OF "у"

PARAPET PARAPET

GROUND
LINE

CROSS ~ SECTION

NOTE: LEGS ОН BAYS ARE 6FT. OR LESS IN LENGTH

Figure 39. Cross section and typical plans of special trench
used with artillery emplacements, (Camouflage omitted.)

under a camouflage net, they normally are constructed
and occupied by artillerymen and by personnel at rear
installations.

b. Construction. The special trench is 2 feet wide,
or less, and from 3 to 5 feet deep. It is dug in short
lengths, in the shape of a chevron, a Y, or any other

PARAPET

TRENCH
BOARD

ҒІНЕ POSITIONS
STAGGERED
BOTH SIDES
OF ТВЕМСН

PARAPET
EL8OW REST

@ Cross section.

Figure 40, Standard trench.

trace which fits into the space available, Changes in
direction are made to reduce the effects of bombs, ar-
tillery shells, or aerial strafing.

48. STANDARD TRENCH. a. Purpose. The stand-
ard trench (fig. 40) offers, much less protection, is
harder to conceal, and requires more time and labor
to construct than foxholes. However, it improves coni-

1
2 ЕТ.

FIRE POSITIONS
5

Figure 40. Standard trench—Continued.

— en,

ELBOW REST

munication, control, supply, and evacuation. 'The use
of trenches is а command decision. Standard trenches
might be used to advantage in the following situations:

(1) Communieation trenches in stabilized situations
where either concealment is available or the advantages
to be gained justify exposure.

(2) Entrances to shelters or groups of shelters.

x2" ORIkA"

OFFSET OF
CROSS SECTION STRINGERS
PROVIDES FOR

OVERLAP AT
OUTER EDGE OF CROSS PIECES JOINT
4" FROM END OF STRINGERS he" OR Ta"

SIDE ELEVATION END ELEVATION
OF SUPPORT OF SUPPORT
Figure 41. Detail of trench board and support.

(3) Operations in extreme cold, where the soldiers,
who remain in heated shelters until the last minute,
must be able to get to firing positions under cover.

(4) In jungle and forest warfare, where movement
of tanks is impossible or very restricted and where
there is concealment from all types of enemy observa-
tion, particularly aerial photography. ;

b. Construction. The standard trench (fig. 40@)
is 4 feet wide at the top, 2 feet wide at the bottom, and
515 feet deep. The spoil is used to construct an irregu-
lar parapet 3 feet wide on each side of the trench. То
aid in concealment, the trench is irregular in plan (fig.
40@) and is built in short sections. Trench boards
(fig. 41) should be installed in all standard trenches.
Lumber or cut timbers may be used. The trench is
deepened so the top of the trench board is 515 feet
down, and the bottom of the trench is shaped into &
trough for drainage. In soft ground, supports for
flooring are required.

e. Fire positions. The standard trench is used
either as a fire or communications trench. Fire posi-
tions (fig. 40) are staggered 5 to 10 yards apart on both
sides of the trench. They are dug 2 feet wide, 214 feet
into the trench wall, and deep enough so the ground
line is chest high. Fire positions are constructed in all
standard trenches both to increase combat effectiveness
and to prevent the enemy from distinguishing between
fire and communication trenches.

SECTION V

FIELD ARTILLERY
EMPLACEMENTS

49. GENERAL. a. This section is a guide to the con-
struction of protective works for field artillery weapons
and personnel Field artillery filed fortifications pro-
vide protection for—

(1) Individuals and small groups such as observers,
command post personnel, the battery executive, switch-
board operator, and others.

(2) Ammunition.

(3) Gun crews.

b. Fortifications are planned to—

(1) Permit delivery of fire within prescribed zones.

(2) Permit direct laying against tanks.

(3) Take advantage of ground formations to lessen
labor.

(4) Take advantage of natural cover and ‘conceal-
ment.

(5) Allow the piece to bé moved quickly to an alter-
nate position.

(6) Provide personnel protection against artillery
fire and air bombardment.

(7) Be simple enough to construct with minimum
effort and time.

(8) Provide comfort during prolonged occupation.

e. Fortifications are begun as soon as practicable
after positions have been selected. They are so planned
that their progressive improvement is possible, using
tools and materials supplied in tables of equipment,
supplemented only by such additional material as is
locally available. It should- not be assumed that the
occupation of a position may be so brief that fortifica-
tions are unnecessary.

50. PRIORITY OF CONSTRUCTION. a. On going
into position, work is done to gain the following results,
listed in their general order of priority:

(1) Ability to deliver fire on time.

(2) Concealment.:

(3) Protection of personnel and ammunition.

(4) Alternate firing positions. Sometimes this
may be third priority.

(5) Other protective measures.

b. The following is an example of the procedure fol-
lowed by a 105-mm howitzer section in daylight occupa-
tion of a previously selected position:

(1) Place the piece in firing position, prepared for
all-around fire if required; lay the piece and otherwise
prepare to execute fire missions. Concealment is taken
into account in selection of the position, and contin-
uously thereafter.

(2) Construct necessary camouflage.

(3) Dig entrenchments for personnel and shelters
for ammunition.

(4) Repeat above procedure for alternate positions.

51. PROTECTION FOR PERSONNEL. Standard
types of entrenchments are employed for protection
against aerial and artillery bombardment as well as
possible ground attack.
`a. Personnel at supply points, in bivouacs or assem-

bly areas, and at installations other than gun emplace-
ments are best protected in foxholes (par. 31) or prone
shelters (par. 34).

b. Personnel] at gun emplacements may utilize spe-
cial trenches (par. 47).

с. Personnel employed as observers occupy modified
foxholes or covered observation posts (par. 86).

d. In stable situations personnel protection may be
increased by constructing appropriate shelters (ch. 5).

52. AMMUNITION SHELTERS. The construction
of ammunition shelters begins as soon as the battery has
prepared for firing and is concealed (par. 50). Shelters

are so located and constructed that they are well con-
cealed, protect ammunition against hostile fire and the
weather, and contain the quantities desired near where
they аге (о be used. Usually projectiles, powder charges,
fuses, and primers are stored in separate shelters, at
least two shelters for each item, so that a direct hit
cannot destroy all of any one of Өег, The protection
required for the several components of separate loading
ammunition is the same as for complete rounds of fixed
or semifixed ammunition. The following methods are
employed : |

a. Initially, or where ground conditions limit ехса-
vation, ammunition is placed in natural depressions
and dispersed in relatively small quantities.

b. Pits may be hastily dug, and branches or rocks
placed at the bottom to prevent contact of ammunition
with wet earth. Я

e. Time permitting, appropriate shelters may be
constructed. Representative shelters for 105-mm and
155-mm ammunition are shown in figures 42, 48, and 44.
For further data concerning the storage and protection
of ammunition in the field, the quantity of ammunition
per shelter, and distance from other shelters required
to localize effects of a direct hit, consult the appropriate
Field Manual or Technical Manual for the weapon
concerned.

(1) Shelters in parapet of emplacement. Shelters
constructed and concealed in emplacement parapéts
(figs. 42 and 43) are convenient for ammunition han-
dling, inconspicuous, and also keep ammunition dry.

(2) Open-pit type (fig. 44). This shelter consists of
a pit for handling and a shelf for stocking ammunition.
Similar shelters may be used in battery dumps.

53. ANTIAIRCRAFT EMPLACEMENT FOR CALI-
BER .50 MACHINE GUN, AIR-COOLED (fig. 45).
This is а circular pit, 9 feet in diameter and of such:
depth that the weapon can engage ground targets.

GROUND LINE

PARAPET

SAND BAGS

DROP CURTAIN
(PAULIN)

FLOOR LINE OF
EMPLACEMENT

4* DIA. LOGS X
6" DIA. LOGS
oe

===
FLOOR LINE OF
EMPLACEMENT

LONGITUDINAL SECTION

Figure 42. Ammunition shelter in parapet. (Camouflage
omitted.)

54. EMPLACEMENTS FOR 105-MM AND 155-MM
HOWITZERS AND 4.5-INCH GUN. Standard em-
placements for all models of 105-mm and 155-mm how-

itzers and the 4.5-inch gun are so constructed that the
same emplacement is suitable for any of these weapons.
The standard emplacements for these weapons аге of

PARAPET

EA 622502255 Y cr Sr
GROUND .LINE 2 D DEN
de з атори

CERA == < =ë 58: ӨГ

6*DIA.. LOGS aa = i E. рэн

~ FLOOR LINE OF
EMPLACEMENT

1 H SUMP

LONGITUDINAL SECTION

Figure 43, Ammunition shelter in parapet with handling pit,
(Camouflage omitted.)

two types: the surface type and the 24-foot-diameter pit
type.

a. Surface type emplacement (fig, 46). This con-
sists of a built-up parapet of earth or sandbags in front

GROUND LINE

2 LENGTH REQUIRED
ENEMY SECTION ON LINE'S: B" FOR 21 ROUNDS-4
А 42 ROUNDS- 8",

Figure 44. Open-pit type ammunition shelter. (Camouftage
omitted.)

of the piece, an ammunition pit on its left side, and
special trenches to accommodate the gun crew. Special
trenches for six men usually are provided on the left ої
the piece and for two on the right,

SAPLING MAT
PLAN COVERING

3' MIN AT
THE TOP

GROUND
LINE

бр À

SECTION

Figure 45. Antiaireraft emplacement for caliber .50 machine gun,
air-cooled. (Camouflage omitted.)

b. 24-foot-diameter pit type emplacement (fig.
47). This consists of а circular pit, approximately 2

feet deep and 24 feet in diameter, with a sloping ramp аб

the rear to get the piece into and out of the emplacement.
The emplacement is surrounded by a parapet approxi-
mately 11% feet high except at the ramp, which usually
is left open to permit rapid withdrawal of the piece.
Ammunition shelters of the type indicated in para-
graph 52 are located in the рагареё on either side of the

незнања

PARAPET

36" шен

AMMUNITION PIT

ARMPIT HEIGHT

HANDLING PIT

SUMP
SP£CAL TRENCH

NOTE.
SPECIAL TRENCH Spoil from special trenches and
ammunition pit used for parapet
If sand bags are used for parapet
fengthen parapet sp as fo provide
more protection for special
trenches.
Figure 46. Surface type emplacement for 105-mm and 155-mm
howitzers (all models) and 4.5-inch gun. (Camouflage omit-
ted.)

piece. To save extra digging after the parapet is com-
pleted, covered special trenches, located under the para-
pet, are constructed either prior to or at the same time
asthe main pit. Spoil from the main pit, the ammuni-
tion shelters, and the special trenches is used to build
the parapet.

SPECIAL TRENCH

ж
8 AA
,

с.
об
— F SAPLING-MAT

GOVERING

AMMUNITION
SHELTER

APPROXIMATE
LIMITS OF SPOIL

SPECIAL
& TRENCH

RAMP
.|r-0N-5 SLOPE

43' APPROX.
PLAN

NOTE:

BY PULLING THE WEAPON TO THE REAR UN-
TIL THE AXLE IS iN THE CENTER OF THE EM-
PLACEMENT, THE WEAPON MAY BE SWUNG
PARAPE T AROUND TO FIRE TO THE REAR OR IN ANY
š DESIRED DIRECTION (FOR ALL-AROUND DE-
3 MIN. FENSE).

GROUND LINE

SPECIAL
TRENCH SECTION THRU RAMP

Figure 47. The 24-foot-diameter pit-type emplacement for 105-mm
and 155-mm howitzers (all models) and 4.5-ineh gun. (Camou-
flage omitted.)

5663979 —44— 1 93

55. EMPLACEMENTS FOR 155-MM GUN. а.
There are two similar types of emplacements, one for the
155-mm gun МІ (fig. 48) and the other for the 155-mm

5
c
a.
&
$ [x AMMUNITION
г Ss SHELTER E
E RAMP DOWN ——— q ——
ес SN — 7 Бе
Ce S ааг Й

TRENCH SPECIAL TRENCH 6' DEEP

SAPLING-MAT
COVERING

— 70' APPROX:
PLAN

3' MIN.
Т, PARAPET, GROUND
3 и LINE
= - ХЭГ” U” а

tees HANDLING PIT
sume”

SECTION THRU RAMP

Figure 48. Emplacement for 155-mm gun M1. (Camouflage
omitted.)

gun M2, МЗ, or modified ӨРЕ (fig. 50). Тһе only
difference іп the general lay-out and construction of
these two emplacements is that the emplacement for

the M1 gun is somewhat larger and has no recoil pit.
An alternate emplacement is required if it is necessary
to cover & greater sector of fire than that provided
by normal traverse in the emplacement.

b. Each of the two type emplacements is & fan-
shaped pit about 2 feet deep, with a ramp at the rear.

Figure 49, Lay-out of emplacement for 155-mm gun M1.

Ammunition shelters are located in the parapet оп
either side of the piece. Covered special trenches {0
accommodate the gun crew also are located under the
parapet. Тһе parapet and ramp are built as described:
in paragraph 54b above.

e. Тһе outline of the emplacement is marked out on
the ground, as indicated in figure 49 for the M1 gun,

APPROX, LIMIT OF SPOIL

аў. SHELTER

AMMUNITION

HANDLING ит

52' АРРКОХ:

”
«j X SPECIAL TRENCH
у 6' DEEP

SAPLING- MAT
COVERING

І-ОМ-5 SLOPH

PLAN

PARAPET

GROUND LINE

SECTION THRU RAMP

Figure 50. Emplacement for 155-mm gun M2, МЗ, or modified
СРЕ. (Camouflage omitted.)

and in figure 51 for the МО, МЗ, or modified GPF. Тһе
center line of the emplacement is along the principal
direction of fire of the weapon, which is indicated
before lay-out and construction of the emplacement are
started.

56. TRAIL SUPPORTS (fig. 52). Trail logs facili-
tate traversing the 105-mm howitzer beyond its normal
limits, They are especially desirable if wide-angle or
all-around fire is necessary. Except in wet or soft
ground during continuous firing, the 155-mm gun and

Figure 51. Lay-out of emplacement for 155-mni gun M2, М8, or
modified GPF.

howitzer require no trail support beyond that afforded
by the trail spade. This support is provided by placing
a large log or timber under the shoe perpendicular to
the trail. Тһе timber should be 12 inches square and
12 feet long, extend 6 feet on each side of the spade,
and be flush with the ground surface.

57. WEAPONS PLATFORM (fig. 53). If timber is
available, an improvised log platform may be con-
structed by burying three or four sills in the ground

B" DIA.
TIMBER

GROUND LINE
8" DiA, TIMBER

Figure 52. Detail of trail supports for 105-mm howitzer.

parallel to the direction of fire, and laying upon them
at right angles, a row of straight logs. These can be
held in place by wiring or spiking the top layer to the

sills, or by covering the entire platform with 6 inches
of earth, Тһе top of the completed platform should
be flush with the ground on either side.

TO LINE OF FIRE.
Figure 58. Gun platform for 105-mm howitzer,

SECTION VI

ANTIAIRCRAFT ARTILLERY
EMPLACEMENTS

58. GENERAL. This section is a guide for construct-
ing protective works for antiaircraft guns, personnel,
and matériel. Such construction takes several hours.
So that it can be done in an efficient and orderly man-
ner, certain parts of the work are given priority.
Highest priority always is given to the mission. When-
ever possible, for purposes.of secrecy, new positions
are constructed and occupied during darkness, all
camouflage being completed before dawn. The follow-
ing outline gives, in general, the procedure to be fol-
lowed in fortifying a position.

a. Ешр|асе matériel ready for firing as soon as pos-
sible. If the position is to be excavated, matériel is
emplaced off to the side oi the final positions.

b. Dig foxholes or special treuches near the em-
placement for personnel.

с. Provide hasty camouflage, if working in daytime.

d. Make necessary excavation at final position.

e. Emplace matériel in final position with minimum
interference to mission, and put in firing order.

f. Continue to build up and fortify the position as
time permits.

59. REQUIREMENTS. a. While it is desirable to
give every protection to persounel and equipment, the
prime consideration always must be the efficient, use of
the equipment. А typical fortification for antiaircraft
matériel embodies the following features:

(1) A parapet 3 to 4 feet high surrounding the em-
placement. 'The parapet should be at least 3 feet wide
at the top, and its outside slope should be from 807 to
45°. See tables XXIII and XXIV for required thick-
ness for different materials.

(2) An inner diameter of the absolute minimum
permitting efficient operation. "Тһе inside walls should
be made as steep as the soil permits, preferably a slope
of 12 on 1.

(3) An inside depth permitting the gun or instru-
ment to depress to its minimum elevation. IÍ the guns
are located on level ground or at the bottom of a valley
where all targets must bé above the horizontal, the
parapet can be built to trunnion height.

(4) Barrel stops preventing fire into adjacent units.

(5) Provisions for drainage.

100

b. In stabilized situations it is desirable to remove
the wheels of the 40-mm gun to a place of greater safety ;
but if the situation is such that the fire unit may have
to move at a moment's notice, this cannot be done.
Sandbagging the wheels is advisable, provided it does
not interfere with operation of the weapon. Also, in
stabilized situations the bogies of 90-mm guns are re-
moved, provided a draw bar is available for the pur-
pose. If they are not removed, they should be covered
with sandbags for their protection.

60. SHELTERS. a. Personnel, Normally, protec-
tion 1s required against blast and splinters of shells and
bombs and penetratión of small-arms bullets. Such
protection is obtained by dispersion and concealment
and by use of foxholes (par. 31) or special trenches
(par. 47) located’ in the immediate vicinity of the
emplacement. .

b. Ammunition. (1) Some ammunition is stored
in niches in the parapet of the emplacement. Fre-
quently ammunition cases buried in the parapet, with
open ends flush with the inside face of the parapet, are
used for this purpose; or types of shelters similar to
those described in paragraph 59 may be used. А suit-
able cover must protect live ammunition from being
struck by ejected shell cases.

(2) The bulk of the ammunition carried by the gun
battery 18 stored in battery dumps. Usually two are
built per battery. Where time is limited an open-pit
type of ammunition shelter may be used. (See par.
52с(2).) However, shelters with 3 feet or more of
overhead cover are better. А trench or pit covered by
8-inch or larger logs and earth is one suitable type. А
cut-and-cover shelter, similar to the one shown in figure

101

86, may be used both as an ammunition shelter and to
Store extra equipment. А trench or sandbagged pass-
ageway with at least one right-angle turn to retard
blast effect should lead to the entrance of the shelter.

61. GUN BATTERY EMPLACEMENTS. a, 90-mm
antiaircraft gun МІ on MIAL mount (fig. 540).
Unless it is possible to prepare the emplacement ahead
of time, the emplacement for the gun on the М1А1
mount is built in two stages: first, the main pit, ramp,
and outrigger trenches are excavated; the gun is then
emplaced, leveled, and prepared for action; second,
parapets are built and, when necessary, revetted; am-
munition niches are provided; outriggers covered; and
the ramp closed off. Note that—

(1) The outrigger trench is covered to prevent њ
break in the parapet, and yet in a manner to permit
ready withdrawal of the outriggers. It is overlaid with
brush or boards and covered with dirt in sufficient depth
to make a continuous parapet around the gun.

(2) Protection is furnished in the ramp by a wall
of sandbags or a revetted dirt wall that can be readily
removed.

(3) Four ammunition niches are provided. Each is
formed by placing four boxes of ammunition in the para-
pet with ends flush with the inside wall and then re-
moving the exposed end of each box.

(4) А short tunnel is built in the parapet for the
power transmission cables.

b. 90-mm antiaircraft gun M2 on M2 mount (fig.
543)). The emplacement for a gun on the M2 mount is
similar to that for one on the M1A1 mount described in
a above, except that it is somewhat larger, has a ramp
at either end, and has а greater inside depth.

102

с. 4.7-inch antiaircraft gun МІ оп MI mount (fig.
54(3). Тһе emplacement for the 4.7-inch antiaircraft
gun is similar to that for the 90-mm gun M2 on mount

OUTRIGGER TRENCH

MUST BE COVERED TO
PREVENT, BREAK IN THE NICHE FOR 4 BOXES

PARAPET AND YET PERMIT 3 {4 ROUNDS EACH)

READY WITHDRAWAL < Qf 0 ‚ AMMUNTION °
s 1/42

CONSTRUCT ALTAN

AROUND PARAPET:

GROUND LINE REMOVABLE SANDBAG.
T

BREASTWORK

7 АН TO LOW
THRU PARAPET hw вата

SANDBAGS

RAMP ION 5 SLOPE

SECTION "А-А"
© 90-mm antiaircraft gun M1 оп M1A1 mount.

Figure 54. Guu battery emplacements, (Camoufluge omitted.)

163

M2. Basically, it is a circular pit 22 feet in diameter
and 6 feet 3 inches deep from the top of the parapet.
The pit is provided with niches for the side outriggers
and with two ramps for the front and rear bogies.

COVERED AMMUNITION
NICHE. CONTAINING
FOUR BOXES

ul
а
212 PARAPET
NOTE: 5 Ч
REMOVABLE SANDBAG 2
BREASTWORK MAY ВЕ . 19
PLACED AT ENDS OF [«—— 9-6"
RAMPS. TO WITHDRAW
PLAN MATERIEL REMQVE

SANDBAGS

468 TO CENTER
SECTION "A м ОҒ EMPLACEMENT

Г SECTION "BB"
THRU AMMUNITION NICHE THRU OUTRIGGER TRENCH

®© 90-mm antiaircraft gun M2 on M2 mount.

Figure 54 Continued.

104

d. Power plant M7 (fig. 55). The emplacement for
the МТ power plant is a rectangular pit 914 feet long,
815 feet wide, and 615 feet deep from top of parapet to
bottom of pit. An extension should be connected to the

‚„_ FOUR BOXES EACH, PROJECTILE
SLOPE RAMP ION 7^ AND PROPELLING CHARGE,
BOGIES ROLLED INTO RAMP BLOCKED | , STORED UNDER BOGIES AND IN
AND COVERED. | “OUTRIGGER TRENCHES.
2

OUTRIGGER TRENCHES
COVERED OVER AFTER
GUN IS EMPLACED.

NOTE: REMOVABLE SANDBAG
BREASTWORKS MAY
BE PLACED AT THE
ENDS OF THE RAMPS.
THIS SECTION MUST
BE REMDVED TO
4 WITHDRAW MATERIEL.
DETAIL THRU
OUTRIGGER
ТВЕМСН

Вів то ceNTeR—
®© 4.7-inch antiaircraft gun M1 on M1 mount.
Figure 54—Continued,

exhaust'to carry the fumes out of the emplacement. The
transmission cable is buried, as indicated in n below.
e. Director M4 or M7 (fig. 56@). The emplace-
ment for the M4 or M7 director is a circular pit about 8
feet in dianieter and deep enough to protect operating

105

personnel while allowing full use of the director tele-
scopes at low elevations.

f. Director, М9 or MIO. (1) The tracker for the
M9 or M10 director must be located in the open. Its

ҮГ ЛБ лайн,
bl: уз»
rae

ИЛ TR

ЭРЭ») Б тү 3 4
>” р “уҹу
7 1) i i NS
2 ЖШ) ЕТІНЕ ^ А N2
SPOIL USED TO PLAN :
CONSTRUCT ALL- REMOVABLE

AROUND PARAPET

BREAST WORK

SECTION
Figure 55. Emplacement for power plant МТ.
omitted.)

(Camouflage

emplacement is a circular pit just large enough to ac-
commodate the tracker head with seats attached. Ex-
cept for depth it is about the same size as the pit for

106

the M7 director (fig. 56@)). It is.less deep since the
telescopes are mounted lower,

(2) The trailer is emplaced in a rectangular pit 16
feet long, 10 feet wide, and 8 feet deep (fig. 56@).

SPOIL USED TO
CONSTRUCT ALL+
PLAN AROUND PARAPET

GROUND LINE

SECTION
@ Emplacement for director M7 or M4. (Camouflage omitted.)

Figure 56.

g. Height finder МТ or M2 (fig. 57). The emplace-
ment for the height finder is a circular pit 10 feet in
diameter and deep enough to allow-the ends of the
height-finder tube just to clear the top of the parapet.

107

h. Height finder SCR-547 (fig. 58). Тһе emplace-
ment for the SCR-547 radio height finder is a pit large
enough to accommodate the trailer. There is provision
for swinging the outrigger jacks into position, and at
one end of the pit is a ramp for removal of the trailer.
This ramp is closed off with a sandbag parapet.

i. SCR-268 (fig. 590)). In emplacing the SCR-268
care must be taken that the outside of the parapet is

REMOVABLE
е; BREASTWORK
* TO CLOSE
ENTRANCE.

3-FT. CLEARANCE ТО

І.
ЭЗЕТ. CLEARANCE CONNECT CABLES

TO SWING DOORS

23-FT. CLEARANCE TO PASS FROM
FRONT TO REAR OF TRAILER

INSIDE HEIGHT TO BE B FT,
Ф Emplacement for M9 or M10 director trailer. (Camouflage
omitted.)

Figure 56— Continued,

circular, so that it will have a constant effect on the ele-
vation antenna.

і. 8СВ-545 (fig. 59@). The SCR-545 is emplaced
in a rectangular pit 30 feet long, 16 feet wide, and 8 feet.
4 inches deep from the top of the parapet. "These dimen-
sions allow a 4-foot clearance on all sides for necessary
servicing.

k. SCR-584 (fig. 59@). The SCR-584 is emplaced
in a rectangular pit 25 feet long, 14 feet wide, and 10 feet.
4 inches deep from the top of the parapet. These
dimensions allow a 4-foot clearance on the back and the

108

two sides, and а 1-foot clearance on the front for
necessary servicing. ;

L. ВС scope. Тһе emplacement for the BC scope is
similar to that for the searchlight control station shown

SPOIL USED TO
CONSTRUCT ALL»
AROUND РАНА-
PLAN PET

GROUND LINÉ

SECTION
Figure 57. Emplacement for height finder M1 or M2. (Camou-
flage omitted.)

in figure 64, Ті is a circular pit just large enough to
accommodate the instrument and manning detail, and
of a depth that does not obstruct the view at low angular
heights.

566397? —14——8 109

m. Machine guns. See paragraph 40.

n. Cables. For protection in static positions trans-
mission cable may be buried in a shallow trench. А
trench of the shape shown in figure 60 is best since it
provides drainage away from the cable. IÍ freezing is

SANDBAG WALL ACROSS
REAR PLATFORM FOR
ADDED PROTECTION,

[^
1

REMOVABLE >
BREASTWORK | 3
TO CLOSE
ENTRANCE

4-ЕТ. CLEARANCE TO 2-РТ. CLEARANCE TO
PERMIT REPAIR OF ` OPERATE JACK
RANGE CONVERTER

UNIT

INSIDE HEIGHT TO BE 6 FT.

OUTRIGGER TRENCHES COVERED OVER
LEAVING 4-FT. CLEARANCE AT INSIDE
OF EMPLACEMENT AND SLOPING TO
5-ҒТ, У ІМ. CLEARANCE AT OUTER END

Figure 58, Emplacement for height finder SCR 547. (Camou-
flage omitted.)

likely, the cable is wrapped in several thieknesses of
burlap or cloth to prevent damage when it is dug up

later. In mobile situations cables normally are not
buried.

62. EMPLACEMENT FOR FIRE UNIT OF 40-MM
ANTIAIRCRAFT ARTILLERY. a. Gun and direc-
tor. The emplacement for gun and director of а 40-mm

110

Goo == SSS
— QUE Е РҮ =
С ЯС
— с. "AM “| DW КА Slt —
=e 77 . SN = :
— СИР COGN на
= М) 4 КА , 2 беж ~ uA 49
Noy + , В < A. N. ыз уыл
4 SEMEN `<
PERSPECTIVE

INSIDE HEIGHT ОҒ EMPLACEMENT
3FT-8(N,

0) SCR-268.

Figure 59. Radar emplacements. (Camouflage omitted.)

111

REMOVABLE
BREASTWORK
TO CLOSE
ENTRANCE

ФЕТ, CLEARANCE EACH END TO PERMIT JACKS ТО
BE EMPLACED.

4-ҒТ. CLEARANCE EACH SIDE TO PERMIT REMOVAL,
OF COMPONENT BOXES,

INSIDE HEIGHT ТО BE BFT. 41М,
(2 SCR-545,

REMOVABLE
BREASTWORK
10 CLOSE
ENTRANCE

i-F T.
CLEARANCE 4-ЕТ. CLEARANCE ТО

OPEN SERVICE DOOR,

4-FT.CLEARANCE EACH SIDE TO PERMIT
OPENING OF OPERATION DOORS.

INSIDE HEIGHT TO BE 10 FT. 41N,
(S SCR-584
Figure 59—Continued.

112

antiaircraft artillery fire unit is laid out as indicated in
figure 61. With the director pit so located, the direc-
tor 15 13 feet {гота the pintle center of the gun and the
dead arc extends 70? to the rear from the side outrigger.
The dead arc extends 35? on either side of the gun-
director line. The director pit is 6 feet in diameter. A

BURLAP OR
CLOTH WRAPPING

Figure 60. Trench for burying power-transmission cable.
(Camouflage omitted.)

short tunnel for the cable conneots the director and gun
pits. The inside height of the emplacement is not over
3 feet 9 inches to permit horizontal fire. Ап elevation
stop is constructed to prevent the gun being depressed
below 400 mils in dead arc. When the director is not
used, there is no dead arc. The ramp is closed off with
sandbags or an earth parapet. It is constructed as a
separate unit to make removal easy. Four ammunition
niches usually are provided in the sides of the pit.

113

AMMUNITION
NICHES

COVER OVER FOR

А DISTANCE ар

OF 2 FEET TO KEEP MUZZLI w 2 ,
FLASH OUT OF EMPLACEMENT NM Мере“ ,
5, ‘ALTERNATE POSITION |” ¢

`x `. ОҒ DIRECTOR < 7

^ - Ни" ”

` M ad =” 7
4. Б ут wo?
PLAN
DIRECTOR PIT

GROUND LINE

SECTION

Figure 61. Emplacement for 40-mm antiaircraft gun and direc-
tor. (Camouflage omitted.)

114

b. Power plant M5 or М6 (fig. 62). Тһе emplace-
ment for an M5 or M6 power plant is a rectangular pit
with a trench for the operator at one end. At static
positions cables usually are buried (see par. 61 n). An

SECTION ON LINE "А — A"
Figure 62. Emplacement for power plant М5 or М6.
(Camouflage omitted.)

extension should be provided for the exhaust to carry
fumes out of the pit.
с. Machine guns. See paragraph 40.

115

63. ANTIAIRCRAFT SEARCHLIGHT SECTION
EMPLACEMENTS. а. Searchlight (fig. 63). The em-
placement for the light is а circular pit 1214 feet in
diameter and 4 feet deep from the top of the parapet.

SPOIL USED

TO GONSTRUCT
ALL- AROUND
DRAINAGE TO PARAPET.
LOW GROUND

ROTE:
REMOVABLE SANDBAG
BREASTWORK MAY BE
PLACED IN RAMP

SECTION THRU RAMP
Figure 63. Searchlight emplacement. (Camouflage omitted.)

At one end is а ramp. It is closed off with a sandbag
parapet after the light is in the pit. Protection is lim-
ited because of the necessity for illuminating planes at
low heights.

116

b. Control station (fig. 64), The emplacement for
the control station is a circular pit about 614 feet in
diameter and 5 feet deep from the top of the parapet.
It provides protection for all parts except the binocu-

SPOIL USED TO
CONSTRUCT ALL
AROUND PARAPET

м PARAPET GROUND ЫМЕ

15
SECTION
Figure 64. Emplacement for searchlight control station.
(Caumouflage omitted.)

lars; these must have an unobstructed view of low-
flying airplanes.

e. Machine guns, See paragraph 40.

d. Power plani (fig. 65). The emplacement for the
searchlight power plant is a rectangular pit 18 feet

117

long, 10 feet wide, and about 6 feet deep from the top
of the parapet. It protects power plant and operator.

REMOVABLE BREAST-.

WORK IN RAMP PARAPET

SECTION

Figure 65. Emplacement for searchlight power plant. (Cam-
ouflage omitted.)

An extension should be placed on the exhaust pipe to

carry fumes out of the pit. Searchlight cables should
be buried the same as other cables,

118

64. CALIBER .30 ANTIAIRCRAFT MACHINE
GUNS. а. Multiple, caliber .50 machine-gun carriage
M51. The emplacement for the M51 multiple, caliber
50 machine-gun earriage is similar to that for the М7
generator trailer (fig. 55) except that it is less deep,
being about 4 to 415 feet in depth, measured from the
top of the parapet.

b. Caliber .50 machine gun, water-cooled, M2, on
M2A1 mount (fig. 66). The emplacement for the M2
caliber .50 machine gun, water-cooled, оп ап M2A1
mount is a circular pit 8 feet in diameter and slightly
less than 4 feet deep from the top of the parapet. There
is an additional 3-foot excavation under the parapet on
one side for water chest and ammunition.

c. Caliber .50 machine gun, water-cooled, M2, on
M3 mount. The emplacement for the caliber .50 ma-
chine gun M2, water-cooled, on an M3 mount is the
same as that for the M2A1 mount described above
except that the depth is less, being about 3 feet from
the top of the parapet, and the inside diameter is
greater, being about 9 feet, у

65. MISCELLANEOUS. а. Command posts. Com.
mand posts are protected whenever practicable. Shel-
ters of the type described in chapter 5 give excellent pro-
tection but require considerable time and material to
construct. Ап improvised command post affording
protection from the weather and some protection from
blast, splinters, and small-arms fire is shown in figure
67. А rectangular pit about waist deep is excavated and
the spoil piled to form а parapet about 11% feet back
from the edge of the pit. The bows from a truck are
placed over the pit, and the canvas top from the truck
is placed over them to form a waterproof covering.

119

Similar shelter is given by a tent placed in а, pit sur-
rounded by a parapet.

VAS

RED RECESS

: FOR WATER CHEST

5, AND AMMUNITION
‚ ВОХЕЗ ~

ГО
45
V

PARAPET | MIN.
GROUND У
LINE

3 ёс . SAND BAG
LOGS -BEVETMENT

‘SECTION ON LINE "A - A"

Figure 66. Emplacement for caliber .50 machine gun, water
cooled, M2, on M2A1 mount.

(Camouflage omitted.)

b. Kitchens. For protection, stoves may be placed
in pits surrounded by parapets. However, when this is
done, care must be exercised to prevent fires or explo-
sions from gasoline fumes.

120

(рађтшо зЯврпошво))

А تت‎ ых эь =m тэ - = —
— € = — ~
-— амь т” T =. E xd
—— тра лам М-С 2
куню OLN Si 8 1604 ONYWWO9 JO
= S1IL30 3504х3 OL 03110 N338

теза» ЗИНИН SVH 1399544 30 КОМНОЧ INOS :310N

AACS
1 "PB
TA i:
44% on
.

=>
>
3
а
f

yona} шолу SAoq рин до) suAuuo Зип 3504 pugurutoo рәвтАолйшу 7,9 940514

121

(peo эЗврпошер) сәЗгегісво 101001 un3-o[drj[nur 10) зпошоовійше 9443 па 780 BINS

"IW 03999085 ний 035070 за ЗЕЕ 2534 а "3814 ПМІМОЛІНОН #3۸1130 01

SNNO 1INH3d LSNW Н1432 :310N

122

e. Radios. Radios are protected in pits; each pit is
just large enough for radio and operator and deep
enough that only the antenna is exposed.

d, Vehicles. "The motor and the tires of 8 vehicle
are the parts most vulnerable to fire effect. А large
pit with entrance ramp will give such parts protection
from blast, splinters, and small-arms fire. In hilly
country partial protection is obtained by digging a cut
in the side of a hill large enough to protect the front
end of a vehicle driven into it. The rear tires are pro-
tected by sandbagging.

e. Multiple-gun motor carriage M13, M15, or M16
(fig. 68). Emplacements for multiple-gun motor car-
riages, which are mounted on standard half-tracks, соп-
sist of pits to fit the vehicles. Each pit must be of a
depth to allow the weapons to fire horizontally, and its
bottom must be nearly level. Access to the pit is by a
sloped ramp. Usually the vehicle is backed into the
pit to permit more rapid exit if the need arises.

123

CHAPTER 5
SHELTERS

SECTION I
GENERAL

66. SCOPE. This chapter covers various types of
shelters employed in combat operations. Included is
а discussion of tactical and technical requirements of
shelters, methods of construction, and type designs.
Ammunition shelters are described in paragraph 99.

67. CLASSIFICATION. a. Based on degree of pro-
tection. Protected shelters are classified according to
the degree of protection they afford.

(1) Blastproof and splinterproof shelters. These
shelters protect against rifle and machine-gun fire,
grenades, and light mortars; splinters of most high-
explosive shells and bombs; and blasts of 100-pound
bombs exploding not closer than 50 feet. They do not
protect against direct hits by bombs or artillery pro-
jectiles.

(2) Light shellproof shelters. Light shellproof
shelters protect against direct hits by 105-mm shells and
fragmentation bombs.

124

(3) Shellproof shelters. Shellproof shelters pro-
tect against continuous bombardment of shells up to 8
inches and direct hits by bombs up to 200 pounds, as
well as against blasts of bombs up to 500 pounds ex-
ploding not nearer than 25 feet.

b. Based on method of construction. "According
to the method of construction, which depends on the
character of the ground, materials available, and pro-
tection required, shelters may be further classified as
follows: .

(1) Surface. Surface shelters have maximum ob-
servation and exit facilities and require a minimum of
labor ; on the other hand, they are relatively conspicuous,
require considerable cover material, and provide the
least protection of the shelters mentioned here. They
are seldom used for the protection of personnel in ad-
vanced positions unless they can be concealed in woods,
on steep reverse slopes, or among buildings; or unless
the underground water level is so close to the surface
that the cut-and-cover type of shelter cannot be used.
Shelters consisting of almost any type of small, impro-
vised shed, covered with a layer of earth, may be used
for the protection of ammunition and stores. These
shelters should be of small capacity, well dispersed, and
carefully concealed. I

(2) Cut-and-eover. (a) This type, intermediate
between the surface and the cave shelter, is constructed
in an open excavation which 1s backfilled around and
over the structure to the level of the original surface,
or somewhat above, The resisting power of the over-
head cover is increased by layers of concrete, steel
beams, broken stones, or other materials with high
resistance to penetration.

566397 ?—44— 9 125

(b) The cut-and-cover shelter is better adapted
than the cave shelter for use as a dressing station. It
18 more quickly constructed, more easily cleaned, better
ventilated, and offers easier means of admission and
evacuation of casualties. However, it usually requires
much larger quantities of materials to provide the same
protection, does not resist intensive shelling as well, and
is harder to conceal.

(c) When the use of cave shelters is impractical
because of surface or underground water, hardness of
underlying rock, or the rapidity of exit required, cut-
and-cover shelters sometimes may be used. "They are
also suitable in wooded areas or in buildings, where con-
cealment is easy and ample material is available, and in
situations requiring immediate shelter.

(d) Unless they are constructed partially or wholly
of concrete, cut-and-cover shelters do not offer much
protection against shells heavier than the 6-inch type.

(3) Cave. (a) Cave shelters are constructed en-
tirely below the surface by mining methods, and have
a cover of undisturbed earth. ‘They are the least con-
spicuous of all types, afford effective protection before
completion, and require the minimum material. Their
disadvantages are: limited observation, congested living
conditions, small exits, difficult drainage and ventila-
tion, and time required to build.

(b) It is difficult to increase overhead protection of
these shelters after completion, since protection depends
upon depth at which the chamber is built. For this
reason, in determining the depth, it is important not
to underestimate the protection needed. On the other
hand, it is equally important not to overestimate it
because of the extra time, labor, and material involved.

126

68. TACTICAL CONSIDERATIONS AND БЕ.
QUIREMENTS. a. Purpose. The primary purpose
of a protected shelter is to permit troops or important
installations to remain in comparative safety at or near
their combat positions during hostile bombardment.

b. Terrain. Reverse slope positions, since they are
difficult for artillery to hit and usually are easily
drained, make excellent locations for shelters. Wooded
areas and buildings, which provide materials and
facilitate concealment, are also desirable.

c. Location. It is of the utmost importance near the
front to have the shelters near where the troops who
occupy them are needed. This rule is relatively less im-
portant toward the rear. Facilities for cover and con-
cealment also influence the location of shelters. Every
advantage which the tactical situation permits should
be taken of natural shelter.

d. Ease of exit. (1) The occupants of a shelter
must be able to get out rapidly. This is particularly
important in shelters located near the front, where
troops must be able to get out and oceupy their fighting
positions in the small time available between the enemy
bomhardment and the infantry assault.

(2) Exit is made easier by designing shelters with
small capacity, minimum depth below ground, and un-
restricted entrances.

(3) Large shelters are provided with at least two
entrances, and preferably with a third for emergency
use. Small shelters are provided with exits as neces-
sary. Extra exits should emerge at a different place
from the main exit and where practicable at points
well concealed or camouflaged. Entrances should be
spaced a minimum of 40 feet apart to avoid the danger
of one shell or bomb burst blocking two entrances.

127

Large systems of cave shelters should provide one en-
trance for every 25 men. |

e. Concealment. „ТЕ is important that the location
and number of shelters be concealed from enemy air
and ground observation. Changes in the appearance
of the terrain must be avoided. Materials and spoil
must be concealed or camouflaged as the shelters are
built, Strict camouflage discipline must be enforced
among working parties. Surface shelters may be hid-
den by terrain features such as woods or buildings.
Cut-and-eover shelters should be kept low.

f. Observation. If practicable, shelters should be
located to afford necessary observation, and should be
provided with means ої observation, for example, loop-
holes in a surface shelter, or a camouflaged: periscope
in the roof of a cut-and-cover shelter.

g. Application of types. Because of the time ele-
ment and the construction difficulties in mobile warfare,
the blastproof and splinterproof shelter is the type
usually used. The necessity for shelter becomes greater
as stabilization develops and details of the position
become known to the enemy. In the rear parts of
the defeuded area, larger and deeper shelters are both
permissible and economical. These usually accommo-
date one or two squads or a platoon. They may be
developed from the emergency shelters initially con-
structed. Shellproof and cave shelters are used only in
stabilized situations.

h. Requirements for shelter in advanced рові-
tions, (1) Shelters in the advanced lines should be—

(a) Well distributed, placing troops close to their
combat positions,

(b) Constructed without going to great depths, to
provide for ease of exit.

128

(e) Provided with direct and easy exits, even at
some sacrifice of cover.

(d) Of small capacity (from, two to twelve men).

(e) Of a type that can be constructed rapidly.

(f) Concealed as thoroughly as possible.

(2) These requirements usually limit the type to the
blastproof and splinterproof shelter.

i. Requirements for shelters in rear positions.
Shelters in rear positions may be larger and deeper than
those at the front. Occupants usually have more time
to emerge after warning of attack. Also in these areas

, shelters can be given maximum overhead cover to with-
stand bombardment of light bombs and heavy shells,
giving occupying troops the necessary rest and a feeling
of security. If underground water conditions permit,
the shelters are built entirely below the ground. "They
are carefully hidden from enemy aerial observation.

69. TECHNICAL CONSIDERATIONS AND .RE-
QUIREMENTS, These include— |

а. Subsurface conditions. Subsurface conditions
such as extent and character of underlying rock, posi-
tion and thickness of impervious and water-bearing
strata, and amount of water to be controlled.

b. Facilities available. Facilities available, includ-
ing time, personnel, tools, material, and transportation.

€. Drainage. Drainage of deep shelters sometimes
becomes a complex problem. 16 includes exclusion of
surface and rain water from the entrance, exclusion of
seepage from the interior, and removal of water that
has collected in the interior.

(1) Surface and rain water. Surface and rain
water must.be excluded from all shelter entrances. If
shelter is enforced from a trench and drainage is slug-

129

gish, two sumps may be dug in the bottom of the trench,
at least 6 feet from the sides of the entrance, and
strongly revetted. The bottom of the trench in front of
the entrance must then be graded to the sumps so that
the highest point is in front of the entrance (fig. 97.)
At times it is possible to dig a sump in front of the en-
trance and grade the trench so that only а limited por-
tion drains into it. Direct rainfall into entrances is
prevented either by the design of the entrance or by the
construction of some form of weatherproof shelter above
it. Baffle boards placed at the entrance floor are useful
to keep out surface water.

БООР SHEETING
CORRUGATED SHEET METAL

SPREADER

Figure. 69. Corrugated metal to waterproof shelter roof.

(2) Seepage. Protection against water seeping
into shelters is important. In a surface or cut-and-
cover shelter this is accomplished by placing tarpaper
between the sheeting and the cover. In cave shelters a
strip of corrugated iron may be placed on the cap of the
frame (fig. 69). Sheeting is then driven over the iron.
Space between caps is filled with an additional piece of
corrugated iron supported by struts. Seepage is thus
carried to the sides of the chamber, where it collects in a
ditch leading to a sump,

130

(3) Removal of water from chambers and gal-
leries. Galleries should be driven on a 1-percent (or 1
foot to 100 feet) grade longitudinally, and all slopes
should fall toward a point or points wliere the water
can be disposed of. If the shelter has a level entrance,
regulate slopes so that water will run to the mouth. The
gallery floor should slope laterally in a 1-percent grade
and a diteh should be dug along one side. In a shelter
entered by incline or shaft, a sump must be formed at
the bottom from which water can be removed by
pumping, siphoning, or bailing.

d. Ventilation. (1) Importanee. Ventilation is
а particularly important factor in cave shelters. Tt
includes the following problems:

(a) Providing sufficient circulation of fresh air im
the incline, shafts, galleries, and chamber.

(b) Gasproofing, or exclusion of gas from all parts
of the shelter.

(e) Providing pure air by means of air purifiers
(collective protectors) when the entrances and ventila-
tion shafts are closed during a prolonged gas attack.

(2) Circulation of fresh air. (a) In surface and
cut-and-cover shelters sufficient fresh air usually is
obtained by keeping entrances open.

(b) In cave shelters ventilating shafts usually are
necessary in addition to entrances, 'They are small
vertical shafts, which may be bored from within after
the completion of the shelter. А stovepipe through a
shaft materially assists circulation of the air. In very
large and elaborate systems of shelters a draft may be
created by fans,

(c) A gallery should not be driven more than 60 feet
without artificial ventilation. A gallery with a single
opening is ventilated by forcing fresh air to the working
end through a duct of wood, metal, or canvas. A pres-

131

sure blower worked by hand or power is an essential
item of mining equipment. For excavations of mod-
erate extent а portable forge forms an expedient venti-
lating device. Drill holes through the roofs of galleries
promote ventilation. In a system of galleries having
two or more outlets, air may be forced out from one
outlet and drawn in through another. Screens or doors
may be arranged to guide the distribution of fresh air.
Vacuum operation is never as satisfactory as а pressure
system. ;

(3) Unventilated shelters. Shelters not provided
with collective protectors should be used only by per-
sonnel who are to remain inactive during occupancy.
Since an inactive man requires about 1 cubic foot of air
per minute, the capacity of unventilated shelters is
limited in part by the difficulty of providing unusually
large shelters. Initial air-space requirements: for shel-
ters for not over 12 men are 150 cubic feet per man.
(See table ПТ.)

Тавһе ПТ. Capacities оў unventilated shelters
Outside air below | Outside air above
90? F. 909 F.

Capac- | Space (cubic fect | Space (cubic feet
Type of shelter (numbor per person)! per person)!
ої men) |— — p
Normal Normal
Rest desk Rost desk
work work

Underground or above-
ground walls of low heat
conductivity?

Aboveground walls of high
heat conductivity,

25 | 3901 540 1 360 725
50 | 400 | 750 | 500 | 1, 000
| 10| 150) 270] 180 860

| 10 200 360 240 500

25 | 235 | 425 270 540
50 | 800 | 540 | 380 720

“л Based on occupancy of 3 hours. >
2 Walls of wood on dry earth have Jow heat conductivity.
з Walls of metal. concrete. Masonry. and damp earth havo high heat conductivity,

132

e. Terrains. Terrain should be considered with
special reference to the effect of slope on the type of
entrance and the rapidity with which overhead cover
can be gained, and to the disposal of spoil.

70. GASPROOFING. a. General. It should be pos-
sible to make all shelters gastight. A shelter not in
use should be sealed to exclude gas. Due to their low.
level, protected shelters are particularly subject to gas
concentrations, and protection must be provided by cur-
tains in entrances. During extended gas attacks men
must be able to work and rest inside the shelter with
gas masks off. This is of greatest importance in shel-
ters where wounded are placed and, in shelters used for
telephone central and signal stations, observation posts,
headquarters, and other activities where the efficiency
of the occupants would be considerably reduced by wear-
ing gas masks.

b. Entrances. The standard M1 gasproof curtain
is used to keep out gas. If it is not available, adjust-
able curtains may be made of blankets on light, sloping
frames, built to: fit snugly the individual entrance.
Frames should be nailed securely to the sides and top of
the entrance timbers. For cave shelters it is sometimes
necessary to place gas curtains оп the steps, but when-
ever possible they should be placed in horizontal en-
trances or horizontal approaches to inclines.

€. Other openings. Windows are covered with sin-
gle curtains. All crevices should be caulked with clay,
old clothes, or sandbags. Plugs, to be inserted during
gas attacks, should be provided for periscope drainage,
and ventilating openings. Flooring or steps in front of
gas curtains should be kept clear of mud and refuse.
Curtains should be kept moist with water or gasproof-

133

ing solutions. Fresh chloride of lime should be kept
on hand and, when the area is gassed, should be placed
between gas curtains at the entrance so that personnel
entering the dugout may neutralize mustard and other
persistent gases on hands and feet.

d. Air locks. Air locks are intermediate chambers
between the outside and inside of shelters. They allow
passage into the shelters, while excluding gas. Figure
70 shows a standard air lock suitable for most types of
surface and cut-and-cover shelters; table IV shows the
bill of materials for its construction. Where desirable,
construction may be modified to provide greater head-
room, Figure 71 shows an air lock used in first-aid
shelters, designed to allow the passage of litters, It is
adaptable to the shelters described in this chapter by in-
creasing their height and width. Table V shows the
bill of materials for its construction.

Curtain doors at each end of the air lock usually are
constructed with standard МІ gasproof curtains. When
an air lock’s outer doorframe projects from the entrance,
the curtain must be about 4 inches wider and 4 inches
` longer than the doorframe. If the air lock is built back
into the entrance the curtain must be the same width as
the doorframe. When not in use the curtain 1s rolled up
and placed on top of the air lock or in a box-shelf above
the top of the doorframe. (For details of the M1 gas-
proof curtain see TM 3-350.)

e. Collective protectors. (1) These devices are set
up outside shelters to purify incoming air by removing
chemical agents. Several types are designed to meet
specific needs, Most collective protectors are driven by
electric motors. Power is provided by a portable gen-
erator set, or taken from commercial sources when avail-
able. Connected directly with the motor is an air blower

134

DIAGONAL f
і

HING

Д TARPAPER
— LINING

| PE MW КЗ h
MÁ 3-4" ce 1-7 Ч -
ТОР VIEW (CURTAINS REMOVED)

к STRIPS Я
CH END

DETAIL D

SIDE ELEVATION i END ELEVATION

Figure 70. Standard air lock for shelter.

135

— ії:‏ ل ل ل ل ا -_________________ a a‏ سس

и зорова тэлсэн тон 3u3I9A 1810],

Z б. сір рипод | с 2 Е ров | — 71. 5. oq

g е (|77777 PUNO DPOP| ее SeN

волт

се зо + (ос није том | јовјелепба 801 “әрім вәцош gg Р 3 тэ4 84181,
(pexoq) 65 25 Ес ЦЭ | ore et ete ek LA | ан a витеуто 330)

6- [Ee ассан цә | 7-777 yoo] РТ 4q soyour g Aq 1 |^ ^ -- 77-- 91498 dog

eg 5 0 СН (7727777 332} ст Áqsopurtp£q]|- 311 Surowig

082 сб 7773eejersnbg |^77 777777777777 воцо 9 44 1 ГП Затчувочв Pus 10014

98 2020 роз youg | 777 4283 OT Aq вәцош p 446 | 11111 90181} 10014

261 |? (|777 това |7777777 999рс1 Aq воцош 0 546 7777777777 77777 aurea

(spunod) зчаюлм | «азобу qua 9218 шө

(OZ 73) 220) 420 popuvjs sof вроагро fo ЦІЯ — "AT 8ЧЧУД,

136

CONTAINER FOR
GAS CURTAIN
WHEN NOT

=
SIDE PANEL A
И

TARPAPER UNDER FLOOR E:
SECTION ОМ LINE "А-А"

SECTION ON LINE 8-8 12" :

(GAS CURTAINS REMOVED)

STANDARD M 1
GAS CURTAIN CONTAINER

lr STRIPS OF
BLANKET

SIDE PANEL Мо!

е2] SIDE PANEL No.2
DETAIL-C DETAIL о
(SHOWING GAS CÜRTAIN)

Figure 71. Air lock for first-aid shelter.

137

CURTAIN
CONTAINER

. SIDE і
PANEL Мо, |

SECTION ON LINE 'E-E"

TARPAPER
LINING

F
TOP VIEW OF ROOF PANEL
I"x6" BOARDS

А 23 = "x
INSIDE VIEW OF SIDE PANEL Мо | 3"3 CLEATS
(SIDE PANEL No.2 SAME-REVERSED) SECTION он LINE F-F'

QOF

SIDE
PANEL No.l

SIDE ——
PANEL Мод

256"
SILL

LINING

OETAIL H ISOMETRIC DETAIL OF J
(645 CURTAIN REMOVED)

138

091
261
96

958

(spunod) 1t319 A,

AH HOO NHNNN DOS

Куцавад)

тал

"воле 1991
эг Р gor ‘әр sououl 9g
nee Capa ША ДЕРЕС ТА
pea ee 3997 ат Aq воцош ç Aq I
ka OPSAT онаа, ор"
банн 29; 21 Аа зецош 9 Aq t

ope ge ис səuour 9 Aq I
проніс зээ) ОТ Aq səuour 9 Ха 2
mate Seals а кта саны SANE ор---7-
oe hee 399] 21 Aq зоцош 9 <q 2
а 399} СІ Aq seqout 8 44 Z

9215

pexoq |

о ee eS ЕРАЗ ов weno
мани: Jaurejuoo итал)
"вувоә
‘SUE

puse | "Зшовад

(I4 '8y) злођоуа pip-jsaif 40} удо} 410 sof зрогагјош fo MA "A ляу,

159

which draws outside air through a metal hose or pipe,
forces it through a canister for purification, and thence
into the shelter. Since concentration of gas invariably
is greater near ground level, the air intake should be as
high as practicable. Тһе collective protector M1, which
16 a typical type, has a capacity of 200 cubic feet of air
per minute under normal operating conditions.

(2) Collective protectors are obtained from the
Chemieal Warfare Service, and are installed in shelters
intended to be used for а considerable time, such as
shelters for command posts, resting troops, and first
aid. Only shelters which have been made reasonably
airtight should be equipped with collective protectors.

f. Sanitary conveniences. Sanitary conveniences
should be provided in all but air-raid emergency shelters
and surface type shelters. Disposal is by chemical
closets, septic tanks, or drainage into special sewers.

71. OVERHEAD COVER. Figure 72 shows a typical
overhead cover for protection against penetration and
explosion of projectiles.

a. Bursting layer. Тһе bursting layer covers the
entire top of the shelter and extends beyond the top a
distance equal to the depth of the shelter floor below the
ground. The burster layer is made of standard bursters
(fig. 78), standard reinforced concrete beams (fig. 74),
rubble masonry, or poured concrete. Table VI shows
required thickness of burster layers for different pro-
jectiles.

b. Distributing layers. The distributing layers
tend to distribute the effects of explosion. Тһе lowest
distributing layer also bears the weight of the overhead

140

cover and transmits it to the berms of natural soil. The
minimum length resting on the berm is equal to the
thickness of the bottom cushion layer, plus 1 foot. Logs
wired together, steel I-beams, rails, or concrete beams set
on edge, are used in distributing layers.

Cushion layers. Cushion layers between burst-
ing layers and distributing layers are made of sand,

r
2 d 1 КАИ A ЈА Loi
кенде 2222

exe: аъ ОВЕ. ËA RIS. Seana 1 CAMOUFLAGE LAYER
AI i i, BURSTER LAYER

Б;

АВА АИ ae?
Эр Оне

oe
2 Seer eal’

3 ut У оби iode мето ue. ТОР CUSHION LAYER
РОАН RE
кее
PSU =! у VASA

ANSA 2%
INB" LOCS WIRED TOGETHER dcs
Low L

DISTRIBUTING LAYER

A use
rent
ул Ç all

угу ие)
ЁОЛ vs ax

yz uS = SGN ЎТ NATURAL EARTH BERM
SUPPORTS PROTECTIVE

Хуа) E
ТАМРЕО EARTH < COVERING,
AR ngi ERU 15

BOTTOM CUSHION LAYER

in ry E 4

un | [we

š ! OTHER SUITABLE MA-

| | SHELTER | TERIALS MAY BE SUB-

З Па STITUTED AS EXPLAIN-
ED IN ТЕХТ,

Figure 72, Typical overhead cover for cut-and-cover shelter.

gravel, tamped earth, crushed rock, or. brick rubble.
Preferably the top layer is of a granular material such
as gravel or crushed rock, and the other layers are of
tamped earth.

566397? —44——10 141

Ч 2
< & Z

Sy СТИ
N Y 1 | Z!
RO | ї Z !

il EN | 1 12 1

ирас рны == = د‎

теты
Ë S J Zl 1

л
Ld

SIDE VIEW

CONCRETE TO BE WEIGHT 145 LB.
(ФЕТ. OF È IN.DIA.ROD

OR #6 WIRE

BURSTER ASSEMBLY

Figure 73. Standard burster block for burster layer.

142

За 9 DEFORMED

1 CONCRETE TO BE
про 2000 088/0. IN. (мін)

MADE tN LENGTHS OF 6,12 АМО (SFT.

WEIGHT 401.85 PER ЕТ.

‘FOR 6'— Q" BEAN -24 FT Vg 0 ROO AND SFT 1/4 Ó ROD
FOR 12-07 BEAM- 4B FT Муф НОО АМО IBFT '/ ф ROD
FOR I5'CO" BEAM- 60 FT МФ ROD ANO 22.5FT 4 Ô ROD

CONCRETE BEAM

Figure 74. Reinforced concrete beam for burster or distributing
layers.

d. Example. Тһе following 18 an example indicat-
ing the design of ап overhead cover to provide protec-
tion against 105-mm projectiles (fig. 72). Materials
available are: standard concrete bursters, logs (8-inch
minimum diameter), crushed rock, and earth.

Assume a design as follows:
1 burster layer
2 distributing layers
3 intermediate layers

(1) Total overhead cover required:

From table X XII, 30 inches concrete.

(2) Burster layer:

From table VI, 10 inches of standard burster
blocks are required, that is, two thicknesses.
Equivalent thickness from table VI is 8 inches

concrete.

(3) Balance of overhead cover:

Equivalent thickness is (1) minus (2) or 99
inches concrete.

143

Taste ҮІ. Minimum thickness of burster layer in inches

Projoctile
Material 100-pound
. 75-mm | 105-mm | 155-mm GP
bomb
Reinforced concrete slab (2,000
pounds per square inch min-
imuin)..-.---2.22-2.-9-22--2 5 8 16 24
Standard reinforced concrete
burster blocks or beams. 5 10 20 30
Rubble masonry-..-.-...-....- 8 12 24 36

(4) Distributing layers:
Use two layers of 8-inch logs, or total of 16 inches.
16

From table VII, equivalent thickness is g ог 8

inches concrete.
(5) Cushion layers:

Total equivalent thickness is (3) minus (4) or
14 inches concrete.

Use three layers, top layer to be granular mate-
rial, that is, crushed rock, and other two lay-
ers to be tamped earth.

Bottom cushion layer should be approximately
2 feet thick, or, from table VII, the equivalent

thickness is: T. or 315 inches concrete (ap-

proximate}. This leaves the equivalent of 14
minus 315, or 1015 inches of concrete to be di-
vided between the remaining two cushion
layers.

Middle cushion layer (tamped earth):

From table VII, 103 times 7 equals 36 -- inches
or 3 feet. (approximate).

144

Upper cushion layer (crushed rock) :
From table VII, 105 Š times 3.5 equals 18 +
inches, or 114 feet ( NUM

TABLE VII. Relative thickness of materials required to provide
same overhead protection

Material MEN
Reinforced сопсгеўе-------------—-------------- eras 1
Rubble masonry... aah Ен 1.5
Logs, 8-inch minimum diameter____----.___-------- 2
Crushed stone or дтауе1-_------------------------- 8. 5
'ramped earth... ааыа л ere 7

72. STANDARD CONSTRUCTION MATERIALS.
a. General. Standard materials for construction of
protected shelters are supplied by engineer agencies.
Their use results in economy of materia] and labor, but
they require transportation. Іп ordering these mate-
rials, if the size timber required is not available, a larger
size may be substituted.

b. Timbers. Round timbers cut near the site often
will be used in place of dimensioned lumber. Table
VIII gives sawed timbers and equivalent round timbers.

145

TABLE VIII. Equivalent timbers used as beams

Equivalent
Sawed timbors (width by depth) | Area (занага | roind timber | Area бзачаго
inches)

1:Вуг4 esses aces 4 3 7. 1
Deby 6-2. а ваш ниши 9 4M. 15.9
2by4_ e ur p de E 8 4 12. 6
2by6___._ ЕКИ ИК 12 5 19. 6
2by8. ecl. ша 16 6 28.3
2-by 10 сада 22252 20 7 38. 5
3 by 3.....-.--- шал, 9 зи 9. 6
З ру ашаам 18 6 28.3
З by 10.2.2... ша 30 8 50. 3
3 by У ро tease 36 9 63. 6
У IE LIS лы Da 16 5 19. 6
5 by 10........- MS SEHE 50 10 78. 5
6 by 6-.--- "—— эээ 36 7 38. 5
S by Вас лав E 64 10 78.5
8 by 123 96 13 132, 7
8 by 14........- ETAR 112 14 154. 0
&by 16. ыша саз асы 128 15 177.0
12:by 12352252 а 144 14 154. 0

NOTE. The equivalent round timbers are also safe as columns. Іп making up the
table, primary consideration was given to resistanee to bending. However, іп every
ease the round timber will resist more vertieal shear than the timber of rectangular
cross section to which it is equivalent.

€. Corrugated steel arches. Arches are made from
heavy corrugated steel. Figures 75, 16, and ТТ show de-
tails of standard types. The gauge of the corrugated
metal sheets will vary with the type of overhead cover
to be supported.

146

CROSS SECTION
ELEVATION

APPROX WEIGHT
PER PLATE (L8)

[GAGE [МЕНТ |

Ге тю | h-a"
|—4 | 56 —] ALTERNATIVE
FOOTING

Figure 75, Corrugated metal arch for two-man shelter,

1
> PLATE

FULL PLATES

CROSS SECTION

ANY MULTIPLE OF 2'-6*
STD,5-O"PLATE
2“ || 5тр,2—6" 2'-e" 2"
PLATE STAGGER Г

ІШІШІ
ALL PLATES ARE INTER—
CHANGE ABLE SIZE ШИ
I

ELEVATION
Figure 76. Semicircular corrugated metal arch for shelter.

DETAIL OF
PLATE JOINT

4 $ STANDARD I2-SAGE
PLATES PER SECTION

"APPROX, WEIGHT ,
PER PLATE(POUNDS)

LENGTH [FULL
OF PLATE |Р PLATE
[

LATE,

| 2-e | 68 | зв |
L 5-0" ат | те |
L 19-0” [рат | изт |

147

d. Gallery and shaft cases. Cases are designed as
linings, without additional material except battens for
use in horizontal galleries, inclined passages, and shafts
driven under ground by mining methods. Cases also

APPROX, WEIGHT NOTE.
PER. LIN.FT.(LB! 6 STANDARD
P FULL PLATES
PER SECTION
187 .
Ex B
226LB.
OBTAINABLE
! IN MULTIPLES
[ 5 |286:8.| OF 27 FT.
LENGTHS UP

O ANO
INCLUDING
10 FT.
Sl
SECTION A--A
CORRUGATED
2”
iit
iB" 4 TARPAPER
BOLT STRIP
DETAIL OF
PLATE JOINT сес СТ
(SEC.B-B) КОЛА OF MULTIPLATE JOINT

RE
ШИШ IOTEN ДЦ

он 2"
р e |
SIDE ELEVATION
Figure 77. Cireular corrugated metal arch for shelter.

may be used in constructing entrances to cut-and-cover
shelters. Note that frames in e below require sheeting
in addition. Dimensions of lumber used in cases vary
with the size of gallery or shaft (table IX). The

148

standard common gallery case, using dimensioned lum-
ber and round timbers, and the improvised shaft case
using round timbers, are shown in figures 78 and 79.

САР 37x10" САР 6" DIA. LOG
3'- 6" LONG э 40" LONG

6-4"
в"

R
[же

COMMON GALLERY IMPROVISED GALLERY
CASÉ CASE

Figure 78. Gallery cases for cave shelters.

SIDE ELEVATION CORNER DETAIL
Figure 79, Improvised shaft case for cave shelters.

e. Chamber, gallery, and shaft frames. (1)
Standard frames are shown in figure 80. They are used
in horizontal or inclined passages, or in shafts, to sup-
port sheeting. In shafts, all timbers of a frame are the
same size as frame posts. Тһе dimensions permit frame

149

spacing not over 4 feet on centers.

provised from round timber.

(2) The chamber frame is used in rooms or cham-
bers of cave shelters. The posts may be 6- by 6-inch
timber, or round straight logs at least 6 inches in diam-
eter at the small end, and as free as possible from knots.
Caps are 6- by 10-inch timber.

САР 6"xB"x 4-0"

6"
SPREADER

Frames can be im-

САР 6"к:0"х 96"

I"x6" SPREADER

€'x6" POSTS

ДЕ А:

CHAMBER GALLERY
FRAME
Figure 80. Standard frames for cave shelters,

COMMON GALLERY
FRAME

f. Dimensions of standard galleries and shafts.
Tables IX, X, and XI give sizes of various classes of
galleries and shafts driven by mining methods, and in-
clude bills of material.

Тавь IX. Dimensions of standard timbered galleries

Size of gallery

Най...

150

Height

6 feet 4 inches
6 feet 4 inches
6 feet 4 inches
4 feet 6 inches

Inside, сїсаг

Width

E 8 feet 6 inches.
INCUN 6 feet 6 inches,
DX 3 feet 0 inches.
аю 3 feet 0 inches.

2 feet 10 inches. ____ 3 feet 0 inches,

2 feet 4 inches

ees 1 foot 10 inches.

UU ''''б б а Бр !аТН т M —— m n.h..1 QW. Й Й(0( Щ-; «ЗВ:

"GL

(POTD)
punod сі’
ТО "54
Ха от £q т ОАТ,
`ur 9 Hg
Ха от 54 ОМД,
Ur F 43 &
4q 01 Хас aug
. Ut P WS
44 01 4q $ 990

{29324 вше

—_ 2 222
89820 оця рио hayol «ор вурмароші fo ці,

penes о
"UL 0 HE
Ха 01 Aq I OAL
076
Aq от 44 £ OM,
шор
Ка от ^ч g aug
`ur9 eg
ка от 44 8 euo

попа

` Seren" OR]
“(рот)
punod 42220
"ur 0318
Aq oF 49 I oA],
Ur g8 4 F
а 01 да 6 OA,
"urge
Ха от да g опо
"urge
Ха 01 Aq $ euo

лен

151

| 709
(рот)
punod 2'0
"ur

"jj 5 44
ка Р OML
"ut
зро Aq
Ха т ом,
ш
37 € Ад
ха с 9ug
"ul
712 Aq
Aq ӯ ouo

әш»
Атә[үвЗ [BUS

HO (o тр че

Or)”
punod 770

"ur

0 31 ¢ Aq
ӯ Aq p OMT,

90181]
Алопва 429824

Ато пошшогу | 410Ц68 18910

(sq)

AES EAD OLF | зчЗтом 18104,

(POT) “(шо
punod y'0 | зөрвөг48) siren

44 томі, |777-77-7--1epseidg

ome

Kiei 194840 ue

зашла} доче рит Плођов sof porsazpiu fo үү

"ІХ arav

152

g. Standard sheeting. Sheeting supports the earth
in chambers and galleries, and in inclines and shafts
where frames rather than cases are used. ‘T'wo-inch
sheeting is furnished for the roof, and 114-inch or 2-
inch sheeting for the sides. Normally, it is in 5-foot
lengths where frame spacing is not over 4 feet on cen-
ters, and in 4-foot lengths where frame spacing is not
over 3 feet on centers, It varies from 4 to 10 inches in
width. Side sheeting is used for headboards and stair-
risers, which are 1% by 10 inches by 3 feet 6 inches in
stepped inclines. Where ground conditions are favor-
able, round poles, 215 inches in diameter at the butt and
4 бо 5 feet long, may be substituted.

NOTE:
CUT FROM 2". 4"
LUMBER.
Figure 81. Wedge for driving sheeting.

h. Wedges are used in driving galleries and shafts
and also to brace timbers tightly against the walls and
roofs of the excavation, holding them in place during
settling. Dimensions of a common-type wedge are
shown in figure 81. Other sizes may be used as needed.

i. Bunk posts. Bunk posts, 4 by 4 inches and 2 by
by 4 inches, respectively, support the double tier of
bunks in shelters. The 4 by 4’s should be placed under
the caps of the frames for additional support. Round
timber, 4 inches in diameter at the small end. may be
substituted.

153

j Use of lumber. Commercial lumber is used for
items such as props, bunks, gas curtain frames, battens
for holding timbers in place during construction, strap-
ping together incline and shaft cases, and making bomb
recesses and baffle boards. Scrap lumber is used with
wedges for blocking timbers in place.

k. Tools. Common tools include pick, ‘shovel,
crowbar, pickmattock, sledge, hammer, saw, maul, ax,
adz, tape, level, plumb line, pliers, and wire cutters.
Special tools, such as the air compressor or earth-mov-
ing equipment, may be of great help.

SECTION II
SURFACE SHELTERS

73. GENERAL, a. Surface shelters generally are
constructed of local materials, such as lumber from de-
molished houses or cut logs covered with earth. Cor-
rugated metal also is employed. They are usually
built for temporary use, or as expedients when the
construction of more protective types is restricted by
unfavorable conditions of ground soil or water. They
are of small capacity, well dispersed, and carefully
concealed. |

b. Most surface shelters give protection only
against effects of blast, splinters, and gas. They are
unsuitable in areas subject to continual bombardment,
and are erected in advanced positions only when they
ean be well concealed in woods or among existing build-
ings, or sited on steep reverse slopes. They are usually

154

oceupied by troops seeking shelter from enemy bom-
bardment or gas attacks.

e. This type of shelter is especially suitable in mo-
bile warfare when the details of a position are not known
to the enemy. Аз the enemy becomes acquainted with
the dispositions, shelters furnishing more protection
are required,

74. 'TYPES OF CONSTRUCTION; a. Wood shelters.
Wood shelters protect personnel against blast, splinters,
and gas attacks of short duration. They can be ех-
tended lengthwise to increase capacity. Baffle walls
divide shelters into compartments. Figure 82 shows
details of one type of shelter that gives protection
against blast and splinters. Тһе bill of materials for
it appears in table ХИ.

b. Metal shelters. Metal shelters are superior to
wood shelters because they are erected more rapidly,
require less outside cover, present smaller targets, and
give greater protection from weather; also, the shelters
arch section gives greater resistance to blast, earth
shock, and movement. Тһе disadvantages are the use
of a critical material and the transportation of the
material to the site. The most satisfactory type to
build is circular, sunk one-third its height into the
ground, and covered with excavated material (fig. 83).
In this type the vertical surface exposed to blast is
reduced, and the earth movement resulting from an
underground explosion tends to lift the entire shelter,
exerting little destructive force. Figures 83 and 84
show corrugated metal shelters which afford protection
against blast and splinters. Tables XIII and XIV
show bills of materials for construction.

155

“236 FLOOR JOIST 218 SILLS

CROSS SECTION C-C"

FRONT ELEVATION

NOTE:
4 WIRE TIES

PER STUD ALL
AROUND,

138" SCABS

CROSS SECTION SHOWING
ALTERNATIVE CONSTRUCTION

Figure 82. Surface shelter constructed of wood and utilizing

156

earth blast wall.

фі аду ROOF а

ње и 0- SANDBAG
КУ MIN. EARTH COVER s ` Zu RI BAFFLE WALL
Y ши шаш K i 3-0"
216 CEILING Sos | Е 5 Сет
АНбАКО d к „>, | ёо46Х-2
[AIR SN : oci EE Ae
ы СК
Ed малу GREG.
о равним
вээ oC] o «ріш,
чує знов зер ERPS |
m 8. iL гі | Ая
236 Е|ОО8 JOIST 3-6 6-0"
LONGITUDINAL SECTION "А-А"
WALLS AND ROOF OF SHELTER TO HAVE TWO 1-6 MIN. рь
THICKNESSES OF 16" SHEATHING, FIRST LAYER TARPAPERL y I&2"COPING
TO BE APPLIBO HORIZONTALLY AND SECOND NS MEC.

LAYER DIAGONALLY. TARPAPER OVER.

2x4 WALER
SECTION "B-B"

i © 65
TARPAPERÍ — ARTH я й
ЗЭЭЛЭЭ ҚОСЫНЫ

Figure 82—Continued.

566397? —44— —11 157

(spunod)
TURIS AM,

------4-------------- piepuejq

"воле
3091 orenbs 801 ‘Pp зоцош og
Е т 5547045 28188-0)

Е А RY POT
DAE IY aa 399] 01 Ха souour 2 А4 T
Е a ЈЕ səuəur 9 441
23 err зөө) 05 £q soqour p Åq &
VE E 399] С; Ха 5оцош 9 Aq 2
РЕ yoo} ОТ Aq sayon; 9 Aq г
2215201 309] 8 Aq soour 9 Aq g
Невена а ҙәр 91 Aq səuour 9 Aq g

M 399] ОТ £q воцош 9 Aq 2
-------- зөө) РТ Aq воцош 8 Aq Z

Ка Ee Чая
9825: с yvy
Gl. og пон
000 р 300} jeour]
ар. рон а УУ puuoq
OOF НЕ punoq
EE... [525 515 Чэ
090 2 172277 3891 әзер
OD AU ERES ET Че
© шинээ РС!
ӨЗ ро у t YBH
$65 "xxx чә
B [DP чоң
SL Етем чов
ба јелен туга yov
&yusut зал

Ыш;

оправа ом ------ POT лу
НИНЕ Нея А естік sseqpusg

See Seem see шшш зедва а],
NOM AME pozruwA[62 SIM

SIEN
T0 5191484 рие Зшаогу

зрнадялня зипувоця рив тоор]
----------- 5199 рив 819 [8 AA

певана ج کے ا ی‎ Пода
cem a کک کے چک و‎ Suiovig

ИИ 75 - врта

EE &jsrof хоор оптвії
"sis pus 'sdvo

‘sysiof Suireo ‘59510[ 20014

шоп

(28 "8ц) 22у poom aonfins sof учет fo nig

ІХ чл,

158

SANDBAG а SANDBAG

1001

по FLOORING 7-2
"oc (

p
©
+
р

Аб,
a BAFFLE |

z ТЕ
ч

PLAN s-os 2
END WALLS SHEATHED

ON BOTH SIDES, I"x6"

INTERIOR SHEATHING CETT

HORIZONTAL, EXTERIOR 176 MINEARTH COVER, SANDBAGS
DIAGONAL. TAR grace" ; Ёс,

CORRUGATED
METAL

STRIP

CORRUGATED METALS
7-6" DIAMETER Í р

GROUND DETAIL OF
SUNEN PLATE JOINT

| | „SHELTER ONE-THIRD
1216” BELOW GROUND LEVEL

2"x6" FLOOR JOIST 2-00.

SECTION ON LiNE"p-B"

Figure 83: Surface shelter constructed of a circular section of
corrugated metal and utilizing sandbag blast wall.

159

43414 CURVED ANGLE

SANDBAG
BAFFLE WALL

ШӘЛІ

+
+
y

шээс ilio ==
и -___-_-- | кавез гэв”
E ДИ МЕТА ШШ || CE
|

р
š
4

MUT
НЯ)

8
(710%

3341 curved ANGLE i

T21BATTEN

+ ыны.

ч СЕ watt,

|. hosok s-o

ЕЕ RUE

LINE oF SANDBAGS- 8

“ра е ЕМО WALLS SHEATHED
1-6" Мин, БАНТ COVER etos қ ON BOTH SIDES. 176”.
2 INTERIOR SHEATHING

HORIZONTAL, EXTERIOR
P DIAGONAL . TARPAPER

Y
254 BATTENS
S F LOORI 2-2 JO" SILLS

SECTION ON LINE"B-B"

Figure 84. Surface shelter constructed of semicircular section

160

of corrugated metal and utilizing sandbag blast wall.

768 e1nSg ut uos 29,98 [80W pojesn1100 18A02-DUe-)n3 991 о} 0518 Ajddu ‘sseqpavs 0644 49410 'sorg;uenb өлөдү "HION.

61605. ок сас как ак вн Е К И RE TT Ек 32194 18301,

"gore
OL ¿g (---------- пом | 399; олепђе 801 ‘apra вәдәш gg |------------------ 1odudiu,
070 1 095 | 9003 exunbg |o 777777777777 7777777777 ор= 25 п ое a Зицувечя
00» 001 (77 300} exenbg | 7777777777777777 вадош 9 44 | (7777777-777777777777 10011
219 y | [7 77 Чон | ^^ 499} СТ Aq ѕәцош 9 Áq g |^ ^7 777 77 яв тва; рия
002 о |--------- Vows |-------- зәәр OT Аа ѕәцош 9 446 |:7777777777777777 35101 10011
: 9 - == = ад ата 4901-07 |__________-_- 5 Ноа ров
085 8 I 9 ----э 4 400j-5(7, 28188-01 prepuwjg! вупи Чл [89U pagen
po Apung шп 9218 шә}

(gg '9U) 4070s ү0јәш рарвталоо зор тв ооо 40/ Sproo јо ma

ЧИХ ялау,

161

(26787) ci tee РИ ОО
T Et live. punog О ОИ ИИА 208
II ID 22223 B d boc EVER UN iE РОТ
684 амин анхлан ioc анхан EE prepuejg
“Bole
OL ГОРИМЫН ЕУ, под | Зөэр orenbs 801 ‘әри soqour og
90% |0809 TTL цову о а қы prepusjg
orc 6», cp E чови (777399) 81 Aq your И Aq p Aq f
000 % 009 (|7777 оо) eaunbg |----------------- seqour 9 Aq I
201 wc OLLI qoup |-------- 325} 8T Aq soyour р Aq 8
759 Өр ре цә |------- 399} ZT Ха soyaurg 446
099 Ж. Бене и цәяя (7777777 3091 ZT Ха вәцәш Qt Aq g
OST 2 uu SEES d pes тэдэ 399] 81 Aq зецоці OT 492
‘ р әна 40019121|---------------э--н--
446 Т % ----әуда ОГО ргеравзе(
ам | Өмнөө — ша Ew

iv dris iae R дода ли],
чает ввварчва
7-7--e[dus роато
"Sut
-чувоця оше puo pus 10014
SSE Р NE suojjeq
Nan S[[IS рив 'sduo "єрпля

Dip NS лотоса

азе ава асын: srodeo[g
7804 рив

SAU чум [ejour poyeznii107)

шет

(28 729) 421248 pppu ротобталоо ‘чоролоицох ‘aonfins sof siap fo mg ‘AIX TEV],

162

SECTION III
CUT-AND-COVER SHELTERS

75. GENERAL. a. Cut-and-cover shelters are the
most common type in combat zones. Тһе shelter is
constructed in an open excavation, and spoil is back-
filled around and over it to the ground level or some-
what above, It is built of local material, sized lumber
or timber, or corrugated metal. Тһе protection afforded
depends оп the type of construction and the overhead
cover. (See par. 71.)

b. This type of shelter is used to protect personnel,
supplies, and matériel. It is especially suitable for
command posts and first-aid or dressing stations, since
it is easily cleaned and ventilated and admittance and
evacuation of casualties can be easily accomplished.

c. For drainage the floors of the shelter slope
slightly toward the entrance. Excavation should be
no greater than necessary to accommodate the shelter,
and dirt should be packed tightly around the frame.

76. TYPES OF CONSTRUCTION. a. Wood shel-
ters. Wood shelters generally are built without floors.
Figure 85 and table ХУ describe a cut-and-cover shelter
built with dimensional lumber. Figure 86 and table
XVI describe the same type of shelter, using logs. This
type gives blastproof and splinterproof protection. The
thickness of overhead cover should not be increased
unless a heavier type construction is used. Figure 87
and table XVII describe a two-man shelter of wood,
built with branch gallery cases.

163

E- 44" POSTS

Me 3 XIO" MUOSILLS
Е 2": 6" SLEEPERS
i56" FLOORING

HS SIDE PANEL МОЛ

+ 4'k4" POSTS

LIE sioe panet мол

1256 STUDS- I2"0.C.

MENT
ЈЕ | CENTER LINE
QF TRENCH A

!
SANDBAGS

ROOF PANEL
м, <
fH
А š
ЗАМОВАС
КЕМЕТМЕМТ |

TRENGH 2 L
BOARDS, 7

SECTION ON LINE "A-A"

Figure 85. Cut-and-cover shelter constructed of
dimensional lumber.

164

o
ш =
= m
3 зо
° 9
z u
1
2 ч
< 2%
Š
a
5 40%
оо a а
rz 3 a
ac і5 2
ш | ш
Ë z ° z
ч © > 2
з 9 т =
°
z
n o
yc >
= ш É
x 4 в. 9
or ы. ш
E ud M
“5 poo
шо о ©
та x 1
то Я бо
в.’
E о
ИК
к m
GROUND

NO.I

6-2" л p ха lm
2xe'srujs i NIS РОТ
DRAINTO Я N TEN

sune) Бс NI 22%. 6" SLEEPERS
|

— —— Q x O"MUDSILL
зв'я азот
SECTION ON LINE “G — GC“

@
Figure 85—Continued.

165

?"x6" PLATE

DOUBLE
SHEATHING

TARPAPER

сыла NND N,

у
N
N
\
6:6; а 220311
5-63 Mosa
5-65 8 M
TARPAPER |
STRIP у
Zue"slLL —
1 SIDE PANEL NO. | - SEC"A- A" METHOD OF

CONNECTING PANELS

B aw
ШТ: 127 бИ 12727 12" be

NOTE: L
їх6"00981 Е SHE ATH-

ING DN ALL PANELS.
FIRST LAYER DIAGO-
NAL,SECOND AT

RIGHT ANGLES TO
STUDS OR JOIST, 2x6"
TARPAPER BETWEEN,

"hm +3" |
SEG/D Mick
г, 2"x6"PLATE 135135

7 NOTE:
END PANEL
№.4-8
ЗАМЕ А$

5748 END PANEL

М0.4-А 2k6"STUDS
REVERSED | `

548
2"х6" SILL 1

SEC?E-E" END PANEL МО4-А

i L
Tz КВ E 75

SX XI
WN

Figure 85—Continued.

166

29288: | ата m A HA Р аса ü

777774399] лвештр |7777 --цвәш your с ‘OPI вәцош ZL
Е n ictus =) лвэш7 хэмнэхийн ---әЗпей-01
08 091 Bootes Wm цә ро 2277777777777777 š рма
y ғ ЕАН punog |----------------- 6 oN ^qour-5
9 9 Sas aa punoq |= P TR АГ

x M MEE ПОДА |i uro EU а талас с лдар ық са
E d eec Ond rr uA E Suo] Your ү нн

уза пита SI. [X АИ ENT 48 3“
684 I чәе P Ур
CET 9 man Tin по | 299] orenbs SDT “рім seqout 92
ZL £ Е. = Чое | 37-37 399) Z1 Ач вәцәш 9 491
009 ‘£ 006 777773e9j emenbg |---------<------------- ор”
POT ВЕРУ 4 772129 зээр олепђе ade peur ЗН яэцэ 9 Aq Í
S8 et Васе Noe 777-00 g1 Ач seqour p iq є
ай ёо ple sss ss qosa |`" T YT op
988 5 12222559 фону | 72502382 329} үү Aq souour 9 Aq &
por 1 85 TTT С 125 22721227 399} СТ Aq SINI 9 Áq 6
#55 үз, ا‎ чову 77770077 399} v] Aq soour 9 Aq 6
789 9T ID ОБЫР ogg 77777007 ләә) g Aq вацош 8 Aq 6
079 ҮР Е e човя 7 399; 91 Aq ѕәцош OT Aq 6
091 є» о WI HOB |-------— 389] 01 Aq вацопт у Aq р
755 C. و‎ Ia цовя 77770007 499} үт Aq зэцочт 9 Aq р

Goh | áum ma ong

pratt tial JIPA [830],

хол, --yunq “Зи эц “әлім
Болох Jung fpoziuvA[82 әлім
pre er Vee Er SSvqpueq
маллан чийн yung ‘sordegg

“SEN
Qon i a speu 8чцоо т

vo a ees а рт 4201 Ary

------------------ тэ4зате 1,
------------- "Sui0UIq oouW

-------------- "т7Вищуваця

Surely yug
Qure} J001 ‘SIOpVIH
STS зв рив $974
зоре ate E ECL ` "врпза
S1adoe[g
Race prr M EE: S3810f јоо
И SR ус Ше pni
57 - 27
rox са ада са 75489

шә}

(48 784) sequen; pouorsuaup fo pojonajuoo 1231248 49000-Dun-jmo 40} арыәрш fo mg "AX "iav

167

NOTE: a Se

STRUTS,BRACE S
AND STRINGERS
ТО BE "MIN.
DIAMETER:

SANDBAG НЕУЕТ-
MENT

А TRENCH BOARDS

ІІІ
A

PRAEDIA
4" MIN.DIA. LOGS

ын
bh

ын

SECTION THRU TRENCH ON LINE "A-A"

Figure 86. Cut-and-eover shelter constructed of logs.

168

„9-9. INIT NO NOJ153S 8

dose, ав SSNS, __ =
„8 РРО NUT M UR TEES c СЯ

-С

s |

Рой نے‎ С.

ЕЕ по ране 33 WIG NIW, S
Y3A09 НІЧУЗ

SECTION ON LINE "C

кїн,

400848319М 3405 901 u313WV/O 'NIW,9

"уза ама ми „У 38 01 S8S39NI81S ONY

5 30798'510815' 51508 YOI 5907
:310м

LOG REVETMENT

Figure 86— Continued,

169

от |” ЧЭ 6 оо о бб рхеривуд POT sdeqpueg
9 Sever УУ ЦОЛ PUR тәте 3199] олапре 801 pra soyour gg |77--------------- Joder,
9), РОМ ЭС атала Тао О И АН ӨН ОЗИНЕ о POG SeN
1 b punog |---=-----------------=--- Зио| Чош | 'e3nes от |7777--------- seu Suyooy
ро —— STE ПОВОДА за ТУ ит ни Е piepuejg [7777777777777 ° HOOT плу
Qg کچ ر‎ чәе (77777 Your © узарту Aq Loyoureyp хахнхцара зөцон9)27777777777777777777 Joo
990 عدا‎ youg |7--вәцәш $ 399} z Aq 193eurerp штитити Бэцой1р | 77777777777777 заолі рел
81 777777UWow | 7 səqgourgI 3991 2 Ха 103eurgrp шпоициш воцош p (7777777777777777 puo [eA
р8 ЭГтттттт цэвэр |^--seqmourg 3991 21 Aq 1одошттр шпици ѕәцощ р |--------------- эр “түз ү
ро vw Tot | --seuour p 3891 д Ха 1әзәштегр шпопини səyəulp |------ 493|9Ц8 Jo avy “51504
Ser. (222707 yoey 177777 пошт Q 399] 0 Aq Jaqaurerp ur urut soour p |7777-7-7--- Атоо surely увод
po^ D | 2225 youd | -ѕәҷош 9 3991 9 Aq 193eurerp Unuitu[Ur sau, p (77777-7 qno 03 “oor ‘JULIJ
p. з мово | səuəurg ләә) Т Aq 1egoursrp ишинд вецош у | 7 оол pus тоор ‘29901.19
0 | рого чову | "seuout Qr 399; ç Aq ледошттр шишиши sogoul p |------ тоол рие хоор 55131416
A3nuentb qun 9215 1193]

——————— — — کک‎ —————— ППИ او ا ا ا ا و‎
(98 80) 491243 бор 42й02-риз-то sof soria fo та ‘TAK зла“,

170

FOR GREATER OVERHEAD PROTECTION A MORE
RESISTANT MATERIAL MAY BE SUBSTITUTED
FOR EARTH FILL,

LINE OF
ÉXCAVATION

STANDARD
TRENGH

‘SLOPE FLOOR —
TO FRONT

TRENGH
BOARDS

TARPAPER
COVERING

Шау ИН iy
Š Y BRANCH GALLERY
CASES
xio“ SPREADER
| 210" BOTTOM LINE

[SAND 65 ЗЭ,
ШШ

1754" BATTEN

2а" т y, nh ОҒ STANDARD
ТВЕМСН سل‎ А
BOARDS Мала ЛЕНЕ ИНДА а далд

FRONT ELEVATION

Figure 87. Two-man eut and cover shelter constructed of
branch gallery cases.

171

OIG ‘T |77---:--

се D OOO и“ поч
8 9 —— o7 Чә
е p ee punoq
€ а, | lE punog
18 2 ед гс Ча
РС, MEE, ват чон
002 1 So ер чону

(опо) Aynuent qun

271----е-------4-|------------е--2---2----.--.4Х.....-.-..... 192194 18301,
вола

заар arends 901 Spa зецо Өр |------------------ зодна 191,
---4---------21.--.2-. равричћу | 777-777---7------s89qpusg
7---:--------------------- POE |7777777------5-----ой
UR T ams museum У ая e cm POL were А SIGN
-------- 399; FI Aq soqout у Aq т |777777-7-7---------sueyWg
EE төө) УТ Aq seqour 8 Aq 6 |----------ә pue pem youg
ت‎ чәч | 77777-77-7----7S0890 Алая)

әй шоп

(18 '3y) «гцаця uəpoom ‘unu-om) sof spou fo jpg ‘АХ HIVE,

172

b. Metal shelters. Metal shelters are quickly and
easily constructed, are blastproof and splintér-proof,
and give the greatest protection against water and earth
shock. Flooring is necessary. Figures 88 and 89 and
tables XIII and EE describe types of corrugated

sien е”
2-27-н-2-8 ee 2-0" миљи иста
2x4 BUE. ne Diagonal. Mr eR

BOLTED OR NAILED
TO FRAME WALL

Ч) AND TO CORRUGATED
METAL.

A و‎ === `
* у К! 553 CURVED ANG
5 и зе ИЕ EO "
Ї1 йн

|
l
al
31

а
|

А WS)
Ly
CENTER LINE ОҒ TRENCH.

PLAN
GROUND
LINE

SECTION ON LINE "A-A"

Figure 88. Cut-and-cover shelter constructed of semicircular

corrugated metal arches.
566397%--44---12 : 173

,B-8, INI NO NO!193S

„01-,1

„2-2 Tn 2-і ;2-2
ELE EERE

NOTE: TARPAPER
QUT SIDE SHEATHING

BOTH ENDS.

531914 T103,9-2015-v
531414 1104,0-01015-9

ININ дмлоно

TVLIW Q31v9nuH05
OL ONY TIM 3^vud3 OL Q3 livN
ча 031108 319Nv QIAN ix эх»

HORIZONTAL
4FULL PLATES
STANDARD

CORRUGATEO

SHEATHING

Z x6"

Је
inued.

Ф
Figure 88— Cont

SECTION ON LINE "C

це

=
«
u
2
o
ш
NE
ом
ам
ч

ахау

174

GROUND LINE

qma m пни Йинал

imp 3m 7А
зам чо GNI

ТҮ

ЦОНХ ЭН

SECTION ON LINE “А-4
пе 19" 8
S CUM 4454 CURVED ANGL

met
НШІ яншуй run fg

SA
14 " лыу
ја сина 5
f 22100
4 фер >
Ë: T'~6"DIAMETER 22222
! ! 3 >= a Р" END WALLS SHEATHED
гэв "FLOOR 201 g

ON BOTH SIDES, Гх6"
INTERIOR SHEATHING
HORIZONTAL; EXTERIOR
DIAGDNAL, TARPAPER
SECTION ON UıNE "B-p" OUTSIDE.

Figure 89. Cut-and-cover shelter constructed of circular cor-
rugated metal arches.

175

7777цвеці youl-g ‘әрі зоцош ZL
posa eae gre етен ө81188-01
еее 77776 Соқ “цош-%

“Bole

399; алапбв gor Sprm soqout gg
“soyoul

у 399} ст Aq your М Ад p Sq +

А зоџош 9 Aq 1
M MENSIS о: ор---=-
77389) рү Aq sayon р Lq g
Pastore 399] 21 Aq зоцош ф Ка g
NOTA 399] 61 Ха вәцош от Aq g
cr 429} FT Aq вөцош 01 542

odo. elu eS prepums{

#86 Е
а eg. |2753 900) 1'&ourT
9 061 (777 400} вашу]
9 @ тз -^--7punoq
681 po — алж ЦЗЯ
9 9 НЕГЕ ЖЕР AE punoq
ії ДЕ. UE рипод
04 е рт: поч
706, Єз. dE ИЕ чови
086 T 208 (777 300} элп bg
£68 FI ECRANS ATH U08
FT po | Тоо YoRy
068 ӨГ. "Toon чової
099 AO [TRIER чон]
181 € 227775 1 нис:

‘ Ф ----eqe]d 300-01
ие { Ӯ тема voor а]

puces Хапивоб gun

ong

здам |6301,
Brae MEE липа ‘Bungou ər A
yung ‘рэ2таз 1839 Эл
в хопа ‘sardeg

аткан ныл کک ج‎ тәйедйізі,

m Ru US HE орфив pessno
SOSS RATO 31128948 рів тоор]
mo pde $9781] yung
хатуурсан 7777777783990)
тетін "вв рив ‘sdvo рид
S10doo[g
URS a Sie came SIES
"SHOQ ров
SMU YIM увдоці poje8nlo[)

(88 AH) „20205 102224 pa0n 1409 4дба02-рит-рпо мурологигя 40f зүрэгэррш fo 140 СТПАХ Way,

176

metal shelters, These provide blastproof and splinter-
proof protection. Figure 90 and table XIX describe a
two-man shelter of corrugated metal which may be

FOR GREATER OVERHEAD PROTECTION A MORE
RESISTANT MATERIAL MAY BE SUBSTITUTED
FOR EARTH FILL,

LINE OF

STANDARD
TRENCH

TRENCH .
|/ SLOPE FLOOR 1
TO FRONT 3 і

тн 2-04

LONGITUDINAL SECTION 7 CORRUGATED
232" CLEATS

2"x В°х 5-0" FLOORING
^8" SILL

GROUND
LINE

i" INE OF
| EXCAVATION
CO METALI AG (Ше
PATE у М | OF STANOARD
а 2124 АЎ "і.
TRENCH xs mM
BOARDS en

FRONT ELEVATION

Figure 90. Two-man cut-and-cover shelter constructed of cor-
rugated metal arches.

either cut-and-cover construction in loose soil, or cave
type in firm soil.

177

$59

[4 6 OUEST punoq
[4 г, aime punoq
96 7 [лг ос под
91 eg НЫЕ: ҷо
[42 б- ubere youq
Бор 8 Ме ов
801 8 7 -8п013998 4001-0

poe syan aun

Я ЕЕ АА ров
БНА VET х POT
"вола

3007 олвпрв 801 “өриа зоцош og
Sona акынды ies рїершв)с
ЭЛЧ QUE 1091 СГ £q səuour 2 Aq 2
паран 499} QT Ха вәцош 8 Aq g
Pre cx ION эЯс8-01 “ивш-ол(,

rade cM VPE 518912)

тттравоадовч риш ‘оор ‘SIRS
‘SHOQ рив

smu IM воцоле peno

ong

шо

(06 '39) 421248 107924 рәруобпллоә иош-ой sof 049101 fo mg “XIX зла,

178

€. Gallery frames or eases. By heavy construction,
similar to that required for cave shelters with standard
gallery frames or cases (par. 72), light-shellproof and
even shellproof cut-and-cover shelters can һе соп-
structed. Such shelters are, in effect, cave shelters con-
structed by cut-and-cover methods. Overhead cover is
provided as outlined in paragraph 71.

SECTION IV
CAVE SHELTERS

77. GENERAL. а. Cave shelters normally are built
in rear areas. They take longer to build than other
types but, when time is available for construction, are
preferable to other shelters because they give maxi-
mum protection.

b. An accurate estimation of the necessary protec-
tion Is essential for economical construction, since it
determines the depth of the chamber. А too-shallow
chamber site gives too little protection, or else requires
difficult and uneconomical later operations to deepen it.
А. chamber set too deep wastes labor, time, and mate-
rials. Frequently in hilly terrain a tunnel dug into the
Side of a hill may serve as a cave shelter, thus elimi-
nating the need for shafts and inclined entrances.

c. Most cave shelters are in earth. Construction in
rock is unusual except in certain types of permanent
fortifications. |

d. Standard methods and materials simplify and
expedite construction. А consolidated bill of materials

179

for a cave shelter built of standard parts may be made
up from the bil] of materials in tables ХХ and XXI.

Exo зе-- h 53- Эвгүй
ж зак a 50- e |
—_— ENTRANGE — — .

45 INCLINE 45 INCLINE

GALLERY TYPE

, aes зола» S]
= u s и oH

21
d, 4$ INCLINE 45' INGLI

12 BUNKS | гевимк5 EH

.
ы
©

c
z
х

€^

RECESS TYPE

Figure 91, Schematic lay-out of gallery and recess cave shel-
ters showing entrances and inclines leading down to shelter.

These tables list the materials required to construct gal-

lery or recess chambers, passages, grenade pits, inclines,
and air locks.

180

78. TYPES. Examples of cave shelters for various
purposes are: |

` а. Infantry cave shelters (personnel). Figure 91
Shows the standard arrangement of both recess and

Ч ООР
ЕЕ r=
s ا‎

=
||

SECTION ON LINE “АА

?"ROOF SHEETING 2'HO* STRUT

SECTION ON LINE "8 —B”
BURSTER LAYERS NOT SHOWN

PLAN
Figure 92, Recess cave shelter.

gallery types; figure 92 and table X X, the recess type
with inclines; figure 93, the recess type with vertical
shafts; and figure 94 and table X XI, the gallery type.

181

VERTICAL SHAFT

AS'INCLINE

GRENADE PIT
SECTION “А-А”

AMMUNITION SHELTERS
BELOW LEVEL ОҒ
PERSONNEL SHELTERS

SHELTERS

VERTICAL SHAFT

TRENCH

SCHEMATIC PLAN

Figure 98. Schematic lay-out of recess cave shelter with ver-
tical shafts,

182

“91481 JO puo )ч 591003007 998

ЇР (891) 468/77777 jesepaweurp |-77777777777 PU ne үргэн гэ э8 89-01 177777 аута розувато Әлі
SSL (09) 088 77777 439} тво - usəur your-g ‘өрім воцош сл 1777777777 Sxunq ‘2914399 әл
891 (ва) 067 || 7 — КЕСЕ NC HE M ERE pspumg rrr вөйрәдү
96 SE cd UE поза [------—- jeep Aq səuour р AG MT || 7777777777777 тод
801 E “yoga | 1 399] p Aq səuour 9 Aq І [77777 777777777777. eq
ZII Ze اه‎ a a” [7777707 392} р Aq вөцош 8 Aq 41 | 7777777777 OC
007 05 Е 77 өөр р Aq soyour OT Aq XT | z 8рчә 3419945
599 (21) басс чозя [o зоөр р Aq вецощ р Ади 77777777777 7077 9q
259 (6) 9F каны цәву (33137777 зөөр p £qseuoutg Aq Ж 007 od
099 (2) ИИ еа ни youd [777 399] p Aq вәцәш 8 Ха МТ || 7777 77777 777 2а
006 (00) сот 7 ysy |--7---- 399p y 4q вәдәпі от Aq iy | сэр "Buryeoqg
00€ (ағ |с чозя [7077007 jeg p Aq зоцошр Aq g | 77 77 од
21% (9) z Ро 3311 qows LL 399) р Aq soqourg AQ g | 77777777 “od
618 QU TT ЦОВД 77727777T 3993 р Aq зацопі g 484 |^ 7 7 2427-2065
posh ер 04 7777 - ҷое |-------- зээр р 4q воцош OT £q g | z do “3urqoəug
816 (T RESI IS qos | 3311 Ләә; 91 Aq sayour р 44 6 |-------------” “сг маа 4804
Р69 (е A yəy 177777777 ЗЭЭР ФТ 54 59Ч901 + АЯ 2 |777777-98ІМ68019 ‘JUBI yung
92% (Е) РАНЕ UE 77777777 9993 Z1 Aq ѕәцоц p Aq 6 | 77 ова пәр шел) xung
491 O OT чозя | зөэр OT Aq вәцәш OT 442 [Z -snng
OST ODE quu n чозя [77777 399p pT Aq sayour p Aq p 777777777777 --xunhq ‘53504
988 2." + ја n pie дәнң (7777-2277 таз) +} Aq зацоц 9 449 | 7777-7 Ар әшедҙ pue 53504
OLLI GG (оп ро цовя 70700000000 000000007 Jequreq) [777777777 souresy Aere)
(реле) | с арені то ong шәп

нн ا‎ — n — nv А

чаи чо

{56 735) 494998 гато 88200. 40f 10743400 2 Я ‘XX TYL

183

001 MD sen каш сс ТЕ о "399 9 Ха вәдош 9 Aq g |-777 7777777777777 “со

£88 OE. | 22272 You 77777077 199] g Aq sayout OT Aq g | 7777777777 z do? ‘JU
750 Ч ро А uo. жкен лай Жейм айык а Ды эы uomo) TER OMIT 8о0ци в Клоо)
092 1 85. са dee 55-9-5556 uounuoo) | 7777777777077 завио BED

spd грригав om],

бо ағаны ылы ыы алақ ҚАЗЫМ арени елек а тээг eoe rer pone ees зубом 18104,

Y (ду ар па ane IT MR POL eo ee UTE SEN
851 (ғ) 8 Вии! CC Е yoo} 8 Aq вэцош 9 Аа 1 |^77777777777777 7777 #19938 Я
096 `g (ә) ӨТ розу: хэв 0177 | са ate ae see Елен чошшогу |-77-77-7-77-77777 soSuo AD

sobnssod om J,

"ЛАЙЫ ӨШ сасе сенікі кы дэн Sk siya pupa ке әй eer ea eens erm учтем [E30],

or (0) от [777777 punog fort 7777777777 77 | Нах od

от (2) 0L | BURO јел пен sss me Puer POC ид N ER STP’ NT
ST (8) et | 77777777 punoq cep 6 ON ‘YOU, |--------------- жина ‘odie

NA í &juent) yun 9218 Баг
рэгт ог)--4242491Ч/)

pənunuoo—(g6 30) 497128 2002 882094 dof prsou fo тя “ХХ TIVI,

184

"91491 JO puo 16 69104100) дән

E ڪڪ‎ Ma MEE ICE л л.

001
(0.21
(GT) 001
2

от

(ФІ) 061
m ре
(2) 09

шоог з--------------ртирив1б
ae 399] 9 Аа воцош OL Aq XT

uer зөө) р Aq ѕәцош от Aq ИТ

— — : 399] + Аа səuour 01 Жа 6
EE 399] р Ха soqout OT Aq ИТ

gI <q ввцэш g 44 f‏ 4891 اید
ттттттэллтцоц цоо)‏ ا کے

Па ИЕ 399; 21 Ха seqour 9 Aq T
deca зээ) р Aq вәцош OT Аа Z
-------- 3993 q Аа 594241 9 Ха МТ
ие 3991 $ Aq səuour от Aq %1
-------- 1201 с Аа =әцош 9 Aq 511
------- 4903 с Ха зацош QT Aq ИТ

ПЕЧ re TET рївод з ува
с (Зигриві u10330q)

шор рив әрі 'Виподца
(8ш

-раві 103404) do} “8шэәчд

PES EET з198 рив влорвон

ақын келе Sa pO MOTOR RE 519393

ИЕ RE: 59589 LABO

кения oq
ағы па siiis c 5Әрів "gurjoeug

185

685 2 78 REE LIE
888 ОР. pU Dt

491 от ел
081 са и
988, б. E GSE

056 81 98'- үт
PZO ‘T Pa Uc
021 'e LE. „етуу voe

(spunod) 131944 | Аздавло

i-r чозя |-77--7-77--777-77777-7399J р Aq səqour QT Aq g
Ligand цовя |7---------<---------фәр – Aq sayout 01 Aq Z
UIN UO (7777777777 gaa QT Aq воцош б 6400
— Чәв{ |--------------------4аа} рү Ад seqout p Aq $
uu ЧовЯ |--------------------499} Фү Аа воцош 9 Aq 9
iced ysg |-777-777--77----------ezis uouluroo ‘S0880 Алотівку
IE поєд |-7---------<-------әдв uoururoo “sour ләре)
пана чові |---7---------------әде ioqureqo 'sourei] Кл9Ц86)
1197]

—— ——ÀÀ—À

GPZ

Р g |-------- punoq
(pexoq)

зе ныс қылдық 4984
2 + pe чов
ҮС бо л "eoe rr чәч
821 po «Доу UO

мае т 44ynuen® чад

Т------------------------------|-------- IUFM [JOL

Weare зар гү ree oes POT | 7 777777777777 7778I8N

--------4---.------------- IW [|77777777-777-78uUI841n9 sexy

— 399} ст Aq səqour 2 Aq Т |-777-7---------eureij шеф

as 329} 9 Aq səupurg Aq 1 |7777--------<-- JOYS тв)

2-205 *--дәә} ZT Aq воцош р Aq 6 |^77777-7------eure1j шер
9218 911

ہے ل ہے ا i‏

8320] 1р om,

репампоб--(26 '8U) 299918 save 352304 sof 10140301. fo Ma “ХХ зла],

186

“ө1481 JO pue 18 39309100; 998

. .

670 “F

(pexoq) 89

14 АЕ qoum
Ob” uS rs pas assia UO
ОЙ. Я punoq
08: Еее punoq
op. JL Dra punoq
008: | do три а 77400] «өч
006: O ла 300} вет
s OT Шин.
ЗН хожоо Эс ХЭ чә
55 ІС ueq
8 БЭЛЭН Wi
фе» (ere НА чә
ү" Босат С yos
IB" lee нео Oe
Яг ay 4054
ТЕ? (nz E цә
буз. qul e Чә
086. LT Bs eae чозя
HEU с с 4094
6:- uu oe ee tee чэн
E сэрнэ тамен your
pp" lero 4284
8L. WI epe youn
9 Ex ete л ше чән
Ж ee Ке Vou
що т уро ЕЕ ово
Per канате CES Цзя

¿S Z Sa ipi ттт-тї-ттлттэттэтэ Юм [930],

ттан ышын а ды ванн mmn meme UIN 0193100 885)
иен кі әкеліне сынын 5Зваризя
ИЕ Nene MER MD 208 ‘SEN
BA SSS APs со аку АМ КЫ AT POT SUSEN

Bee S Na Pat Ре REE 6 ‘ON *ur-% ‘5319819
ылда nas ця иж 2818-01 *pozireAqes OITA

цэн "ur ‘apa чаг ZL ‘BUJU әлм

187

SSSR I Pe mene Я 399] ст Aq seqour 8 Áq T
REET TRS SRT аса оса зөө) 9 Aq seqout 9 Аа I
геол вич Mee ETT 939} 8 Aq sayour 9 Aq
MIND UHR ---499; QT £q зоцош 9 Aq
унал SSS расни 399) 61 Aq seuout 9 Aq
и иста виа ээл, 499; p Ха зоцош p Aq И
Pape ка: 399] $ Aq зоцош 9 Aq %
ety асы ne 399} ç Aq вөцош 9 Aq И
uri pisi Ро eye зээ) р Aq seqour 8 Aq Я
задля Coie ype СОЛО 3993 $ Aq вәцош от Aq Я
манхан 429; € Aq seuout QT Aq Я
S aE ЭНН 393] 9 Ха səqour OT Aq %
зі eS с зөө) р Ха зоцош р Aq
DEED ETE 399] gI Aq 5оцош + Aq
Еак cnc EE 399] РТ Аа зоцош + Aq
Ра 399) 91 Aq зоцош $ Aq
кыла кал Кын ЫК ЕСЕ а К зээ) $ Aq вөцош 9 Aq
о вислані АЕ 199; 9 Aq вәцәш 9 Aq
самалды талды дады ый, 39ə; $ Aq səuour $ Aq

ANA AME S TA

4
Á

1----2-424.1 “-вәйрәм

“POSTIIN; өд 3snur 81149948 jo YIPTA 18401 JUGADA us ING 51440145 JEN? 10) роупдизате 99 Авто APIA 1uo19gIp Jo 30119945 t
7 "399; 9 Jo 43891 HUN 8 20; pombe «өг 800) moys sasoyzuaied ut воля {

20712 бро Р 1577--- i E Бироа Joaren R sees sare ЗЧЭТӨА 18101,

PE- 189 1 DENS Lo Cue EU uu cT 7 77778пооцердо8гиІ

89 96 898 19 = Асы Зла хахаж и. төд

соза | wa | эпо I
ñimun ç

panunuon—(z6 85) 121048 9802 882024 sof үдэр! fo Т “XX savy

188

Aat

2
| — 1
414 BUNK POSTS
ЭН
йөз

КЕТКЕ Ik6"SPRE ADER
SECTION ON LINE "A-A"

PLAN

2"ROOF SHEETING

7 exe CAP
қ 2'kIO"STRUT

INK Posts А
2k4"BUNK FRAME EN |“, 6" SPREADER
6x6" POST
it SIDE SHEETING
4'ke" SILL

SECTION ON LINE "B-B"
Figure 94, Gallery type cave shelter.

566397? —44— —13 189

"peousruanj aq 1snut Зипаоце jo t[2 pLA 1830) JUARA MDI пев yng “Чоц 2811 10) ро 12118415 eq ABUL YIP 1 ө4өрїр Jo 90149949 6
"ава 9 Jo U3U] у 10у рәлтпрәг sor uenb moys 69590309191 ur SANZI 1

51
08

06
805
ZII
021
821
0%
024.
024.
FOL,
079%
021
08%
019,
094 1
vec
286
SPI
079
009
089 $

(spunod)

10319 A

9 Е тес радон |—------------------------- P08
O e puñoq; eo ae E P01
(0) 51 [7777 punog |72777277 6 ON "qour-9;
(00D 009,77 777 jeep төшү |7-------------<-<-----5 93133-01
(08) 001|----- 399; BUY] |7777 цөвөс qout-g рім зоцо gA
(Фе) 8911 7777777777 ЧЕН» Ре as prepuryg
И ен aus Wow |------ 7389] р Aq soqour р 4q ZI
OL! puce em цәзң р п зээ) $ Aq soqout 9 Aq ИТ
S. uev: чов |77777777 399] $ Aq souour 8 Aq мт
66 (7772777 ysy | 77777 399] + Aq воцош QT Aq І
947 06 Io EET I yoeg {77----7- зээ) р Aq sououi + Aq %1
(01) 09 |`” 7 777 ов [77077 399) $ Аа soqout 9 Aq XT
(8) FF |-------7--- чо [77777777 399} р Ха воцош 8 Aq ИТ
(55) 681|77777777777 чозя |^ 7 зөө) $ Ха sayour QT Aq %1
(hy) Sp [Let wow [777777777 303] $ Aq SoqoUI p Аа g
(9) 08 33733371 Wowsp |--------- дөө) р Aq səuour 9 Aq 8
(WIESE. 1275 20280307 чону |--------- 399] $ Аа souout 8 54 Z
(11) 99 |7 377777 чону 777 199) $ Ха səuour OT да 6,
ME Е? чови |7 7777779883 21 Aq зоцой р Aq 2
(Р) 960 (777777777: qoes |-------- 399] РТ Aq вәцош p Aq g
(D) A | 2228-2025 Wow | 77777777 зээ) 8 Aq seqout y Аа Z
КОДАМИ меккелік Чә | 777777 399] 8 Аа 5оцош ОТ Aq 2
(g) тЇ. [т een yeg |----=-=5- 393} 8 Ка sayout $ Ка $
(6) eT рого dou. |за веша: 18910)
т Азцавпо Tun 6218

заз тегу rcc SHEN
a EGE EAN 8914839
TT мапа 'pozruSA[e3 ‘oily
777737777 урд Bupu оп

----<--------4---... водром

UNE TRUE ЛЭ, арника“ за

р Rad нЕ od

plac Sq dcn E од

Е Ta $99138
Te asimyysug] ‘surely yung

"упо 03 ‘оѕтлл5в0лә ‘шеу HUNG
ны ағыза

yang “узо
Азы р анч тал гн 89181} AIBN)

шэн й

жд

1094040
(F6 'Sy) 424108 sano odhg-fisayob sof spamu fo ЦІЯ

ТХХ stavu,

190

b. Command posts (fig. 95). Command posts lay-
outs are not standardized. Note that in figure 95 pas-
sages are common-gallery size and rooms are chamber-
gallery size, similar to those in figure 99. Command

(ENTRANCE СЕ =

COMMAND POST FOR A SMALL UNIT such 9^9"
AS AN INFANTRY PLATOON

ENTRANCE

45" INCLINE

| 3 |
вв 30-6*—4se* st г 222
ї
8-6, 9-6т9-65 өлі 8-р
COMMAND POST COMMAND POST
FOR A COMPANY FOR A BATTALION

a ENTRANCE —————

45" INCLINE

в-619-619-619-619-6р— 28-9"
COMMAND POST FQR А REGIMENT
Figure 95, Typical lay-out of cave shelters used for command
posts, showing entrances and inclines.
191

posts for larger units generally consist of long, re-
cessed chambers along the passage to accommodate en-
listed men's bunks, and small chambers at right angles

2" ROOF SHEETING 4 6XS'CAPS 6%67Р0575
20" STRUTS

pdt RE وک‎ €

ШИ

PLAN
Figure 96. Cave shelter for aid station.

to the passage, normally used as combined offices and
quarters for commissioned personnel. The maximum
length of these rooms without ventilating holes or shafts
is 15 feet. In computing floor space of command post
shelters, the area of passages is not included.

` €. Firstaid shelters, Figure 96 shows passages,
aisles, and inclines adapted Тог the movement of litters.
The rooms are made with standard chamber-gallery
frames, and the connecting aisles with great-gallery

192

frames having caps and sills shortened to 514 feet. The
usual 45° incline is too steep for handling litters and
should be reduced to 31° for this type of shelter.

79. CLASSIFICATION. Cave shelters are classified
as the recess type and gallery type (fig. 91).

a. The recess type is 815 feet wall-to-wall, and em-
ploys the chamber gallery. Тһе passage is at one side,
with bunks perpendicular to the passage. The shelter
is economical in space, labor, and material, requirements
beiug 15 cubic feet of excavation and 113 board feet of
lumber per occupant. It is used wherever conditions
permit.

b. The gallery type is 6% feet wall-to-wall, and em-
ploys the great gallery. The connecting passage or
entrance 15 along the main axis of the chamber, with
bunks on both sides paralleling the passage. Simpler
to construct than the recess type, this advantage is can-
celled by its larger excavation and material require-

` ments—-—93 cubic feet of excavation and 185 board feet of
lumber per occupant,

80. REQUIREMENTS. The factors to be considered
are: approach to entrances; entrances, which may be
inclined or not, as conditions require; room or chamber
proper ; and connecting passages,

81. EXCAVATION. a. Tools. The pick, shovel,
erowbar and pick mattock are the primary tools in
earth exeavation. In advancing an incline or gallery
only enough ground is opened up to accommodate the
timbering.

b. Removal of excavated material. In small head-
ings spoil is shoveled into bags, which are carried to the
place of disposal Im fairly large headings, wheel-

193

barrows and small tramcars may be used. Тһе removal
of spoil through shafts is ordinarily by buckets and
hand-operated windlasses or small power hoists.

e. Concealment. When the shelter is close to the
enemy, spoil is deposited temporarily in those dumps
which can be used by day unobserved by the enemy. At
night men place the spoil in shell holes, old mine craters,
abandoned trenches, sunken roads, behind hedges, or any
other places concealed from the enemy in daylight. It
is bad practice to build mounds of spoil. All material
must be carefully concealed, or camouflaged against
airplane observation, since fresh spoil of whatever color
is easily identified on enemy aerial photographs, The
path to the place of disposal must be concealed, to
prevent the tracks showing on aerial photographs.

82. ENTRANCES (fig. 97). There should be at least
1 foot of initial headcover over the top of the first
case of the entrance proper; and a burster course of 5,
to 19 inches of rock, broken stone, or concrete slabs is
placed above the entrance not more than 1 foot from
the surface. No attempt should be made to strengthen
the head of the incline by logs, rails, I-beams, concrete
arches, extra heavy timbers, or complicated bracing. 14
hit, such material is likely to cause a serious block be-
cause of the diffieulty of clearing away debris in the
entrance. The only protection against grenades being
thrown in (е entrance is a lined pit 6 feet deep at bottom
of the inclined shaft (see fig. 98). This is constructed
after the shelter is completed, and also acts as a sump.
It must be kept clear of debris. Grenade pits are
installed only where ground raids are likely to occur.
The best protection for entrances is concealment from
ground observation and from aerial photography.

194

NOTE:
BURSTER LAYERS

€ NATURAL

GROUND LINE
> x10*x 3-6"
HEADBOARDS

TRENCH

i, STANDARD M t; ñ Ë
BOARDS Ц} GAS CURTAIN У

NOTE: OF ENTRANCE

SLOPE BOTTOM OF TRENCH i xia gae
AWAY FROM ENTRANCE ON 2505
BOTH SIDES. DRAINAGE SUMPS BAFFLE BOARD

BOTH SIDES AT LEAST 6'-0"
FROM ф OF ENTRANCE,

Figure 97, Approach and entrance to incline to cave shelter.

(See FM 5-20.) То avoid ground observation, en-
trances are located on places such as reverse slopes and
along sunken roads. То avoid detection by aerial
photograph, they are located in trenches used for other
purposes, or along other traveled routes. Locating
shelters in woods protects them from both ground and
air observation,

83. APPROACH. a. Definition. The approach is
that portion of ground in front of the entrance to
underground works which must be excavated to provide
necessary headroom without sacrificing overhead cover.

195

The approach usually is necessary, whether the entrance
is from a trench (fig. 97) or from a reverse slope.

b. Approach from reverse slope. Except in cases
where the entrance is from an existing trench, or where
a reverse slope entry is made in а nearly vertical face,
an approach is necessary to reach the first timbered
section. . Usually, it consists of a narrow trench driven
forward into the slope on a slight upgrade to facilitate
drainage, until & vertical face is obtained high enough
for installation of the first gallery case. Revetment
usually is needed near the entrance and, being con-
spicuous on an aerial photograph, the approach must
be carefully camouflaged both during construction and
after completion.

84. DRIVING AN INCLINE WITH CASES. a. Nor-
mal construction, (1) То standardize construction, a
single type of incline, using standard gallery cases
placed vertically, 15 employed (fig. 98). This type,
also known as the stepped incline, may be built by un-
skilled labor. The normal size of case is the common
gallery type.
In driving an incline with cases (fig. 98) the dimensions
of a common gallery case are marked on the ground
at the site of the entrance. Standard common gallery
cases are used except at the top of inclines of standard
trenches, where the posts of the first case are sawed to
5 feet 8 inches instead of 6 feet 6 inches, giving 4 feet
9 inches of headroom. This reduction in the size of the
first case is necessary to maintain adequate overhead
cover above the entrance to the incline.

(2) Excavation for the sill of each successive case
is lowered 10 inches, providing for steps. Cases are
used as described above, except that headboards and

196

COMMON
GALLERY FRAME

OMMON GALLERY CASES BURSTER LAYER
NOT SHOWN

и GROUND PARAPET

MN нь SANDBAGS
ХУ came à ud

кб" CURTAIN
H

T й 15 x10" 3-6"
Lote! HEADBOARDS
ISÉCTION ON LINE A-A

l'x6" BAT TEN STANDARD MI

GAS CURTAINS

STANDARD M I
BAS CURTAIN

Ei x0 3-0 с
SrREADER SECTION ON LINE 'B-B*

Ede -3 РАЋАРЕТ.

CROSS SECTION VIEW

OF 45 INCLINE SANDBAGS | 3%10°POsTs FOR FIRST
й IR CASE сут ТО 5-8"
oT ТЕ
f&G"CURTAIN SHE STANDARD МІ
мот ? Ї GAS CURTAIN
CASES FOR GRENADE | TRE = Idi! TRENCH away FROM
PIT MADE BY CUTTING vm We rt NTRANCE ON BOTH
COMMON GALLERY CASES x I046 H SIDES, DRAINAGE
INHALE ETALONO eine В BAFFLE BOARD 777717. SUMPS BOTH SIDES AT
SECTION OR. LINE "C-C^ LEAST 6-0 FROM 6

(SHOWING ELEVATION OF ENTRANCE.
OF ENTRANCE)

Figure 98. Incline for cuve shelter.

risers are nailed in position to prevent earth from cav-
ing between successive caps and sills. Тһе timbering
follows the excavation closely, to prevent “runs” in
face or sides.

197

(3) In loose, caving soil, the cap must be put in
position first and supported while grooves for the
ground sill and posts are excavated. Two “crutches”
(fig. 99) are used for supports. A crutch is an upright

оке"
HEADBOARO

. SECTION

ее USE IN
STEPPED INCLINE

(SHOWING USE IN PASSAGE) 2"x a"xI0" BLOCK

NOTE:

WHEN USED iN
STEPPED INCLINE
REMOVE 2410

LOCK АМО SHORTEN EYE-SCREW
POST B. TYPE
4"x 4" POST
REAR SID DETAIL AT TOP

МЕМ VIEW

Figure 99. Use of “crutches” in driving gallery with cases,

198

piece of timber carrying a crosspiece equal in length
to the width of two cases. Тһе upright piece rests
upon the ground sill of a case already placed, and is
raised to proper height by wedges. The part of the
crosspiece which projects forward is made 2 inches
higher than the rear part, to support the cap somewhat
above its final level and to allow posts to be easily in-
serted (fig. 99). Тһе rear part is attached to the up-
right piece by an iron rod or short chain. When the
case is set and adjusted to position, crutches are taken
down by removing the wedges, and are placed under the
next cap.

(4) Immediately upon being set, each case is tied
to the top and bottom of the previous one by short
lengths of sheeting. These are later replaced by 1-
by 6-inch battens (see app. I). Тһе number of cases
required for a 45? incline for any depth equals the ver-
tica] depth between levels in inches divided by 10
minus 1.

b. First-aid shelter construction. The construction
of inclines for first-aid shelters is similar to norma]
construction, except that a case of larger size than the
common-gallery type is ordinarily used. While a 45°
slope is usually used for most inclines, a lesser slope is
preferred for first-aid shelters. А 81° slope is fre-
quently used, in which event the number of cases equals
twice the difference in feet in elevation between levels
minusl. This is based on a stairway with 6-inch risers
and 10-inch treads.

85. SINKING A SHAFT. а. With cases, Shafts
usually are sunk with cases. А shaft case of required
Size 18 constructed and placed on the site of the shaft,
dimensions of which are marked on the ground outside

199

the case. The case 1s removed, and a hole is dug to the
depth of the case, which is placed in the excavation
with its top flush with the ground. Its posifion is саге-
fully verified, and it 1s secured in position by packing
earth around it. Excavation is continued for the depth
of another case, which 16 put in place as follows: one
endpiece is placed in position; the sides are engaged
with the end and pushed back into position; а pocket-
shaped excavation is made beyond the end of one of thé
sidepieces and running back 3 or 4 inches into the side
wall; the remaining endpiece is inserted in this cavity
far enough to allow its opposite end to slip over the
. Side and fall into place by drawing against the side-
pieces. The case may be toenailed and fastened to the
higher one by short battens. The next case is placed
in the same way, care being taken not to excavate two
consecutive pockets in the same corner. Pockets are
filled by stuffing earth from below before. placing the
next case. Upon reaching the level of the top of the
gallery, pieces on the gallery side of the shaft are omit-
ted if the ground is firm; but, if it needs support, these
pieces are put in place and secured by cleats or braces.
b. With frames and sheeting. In sinking a shaft
with frames and sheeting (fig. 100), the size and posi-
tion of the shaft are fixed first, then the top frame is
1414 down and staked in place, with guide marks on
the endpieces made aceurately in the desired position.
The excavated area is made enough larger than the top
frame to take the sheeting all around. Usually the
interval between the first and second frame can be dug
without driving sheeting. It should be so undercut
that, at the level of the second frame, it will be larger
in each direction than at the top by twice. the thickness
of the sheeting. Gauge rods, cut to the length and

200

width of the excavation and plainly marked at middle
points, should be provided for ease in measuring. Тһе
inconvenience of working under the top frame may be
avoided by marking the sides of the hole carefully and
digging the first inerval before setting the top frame.

3-6* GROUND CINE TOP FRAME

224" BATTENS |
2" SHEETING

PLAN AT TOP

HALVED

422

ISOMETRIC ОР
FRAME JOINT

COMMON

PLAN AT BOTTOM ` SECTION ON LINE "А-д"
Figure 100. Sinking a shaft with frames and sheeting.

When the shaft is deep enough, the second frame is put
in place and nailed together. The top and second frame
are connected by nailing to them four battens of proper
length, two on each side (fig. 100), which suspend the
second frame from the top frame at the proper interval.

201

The second frame 18 placed vertically below the top
frame, using a plumb line.

Sheeting 15 inserted outside the top frame, beveled end
first, bevel inside, and pushed down until its top 1s flush
with the top frame. The lower end of the sheeting is
wedged out from the lower frame to permit insertion
of second interval sheeting, and excavation of the second
interval is commenced. In ordinary soil, the sides of
the shaft require support. "The sheeting is therefore
introduced as the excavation proceeds, wedges previ-
ously placed being driven down as the sheeting is
inserted. If earth pressure becomes great enough to
spring the sheeting planks inward, an auxiliary frame
is added. "This frame is similar to shaft frames, but
4 to 6 inches larger in outside dimensions. Sheeting
rests directly against the outside of this frame, and thus
is held far enough out to allow the third frame to be
placed and wedges to be inserted as before, Тһе auxil-
jary frame then is removed and used in the next interval.
Successive frames are placed in like manner (fig. 100)
until the one directly over the gallery is reached. This
frame is placed at exactly the right height and the shaft
continued to the required depth. А frame is placed at
the bottom, its top level with the gallery floor, and the
sheeting is allowed to rest directly against the outside
of this frame. When the soil permits the sheeting is
omitted, wholly or in part, over the portion of the shaft
which is to form the gallery entrance.

с. Precautions. In sinking shafts, special саге
must be taken to make the excavation no larger than,
required for placing the lining. If space is left out-
side the lining, the earth inay give throughont the entire
height of the shaft, fall against the lining, and crush
itin.

202

86. DRIVING А GALLERY. а. With cases. The
operation is the same as for driving an incline with
cases, except that the excavation is not stepped and
headboards and risers are omitted.

b. With frames and sheeting. (1) Two gauge rods
are prepared, giving the extreme height and width of
the excavation, that is, the height of the frame plus two
thicknesses of top sheeting, and the width of the frame
plus four thicknesses of side sheeting. Тре middle of
each gauge rod is marked plainly. А gallery frame is

Figure 101. Driving sheeting with beveled cap and cap with
strips nailed to 16.

set up, carefully located, and fastened in position with
battens and braces. The top gallery sheeting is started
on top of the сар and driven until held in place by the
earth. It is given the upward pitch necessary to make
room for placing the next frame and sheeting by a
beveled cap, or by strips fastened on top and on the
rear face of a cap (fig. 101). Тһе side sheeting is started
in the same way against the outer faces of the posts,
and is given an outward slant by bracing the outer ends
slightly away from the sides of the gallery. Earth is
excavated and the sheeting advanced, keeping the front

203

ends in solid earth to hold them steady and to give
protection to workmen. |

(2) When the gallery is advanced one interval,
usually about 8 or 4 feet, а second frame is placed. Its
position is verified by the guide marks; its direction hy
& line; its grade by a spirit, mason's, or field level; and
its plumb Бу а plumb line. It is secured in place by
nailing battens to it and .to the preceding ‘frame.

Figure 102. Using wedges in driving sheeting.

Wedges are inserted between the second frame and the
sheeting, to allow room for insertion of the sheeting
for the next interval, and the gallery is continued by the
same method (figs. 102, 103.) When the sheeting can
be advanced only by hard driving, the frames are in-
clined slightly to the rear and afterwards driven
forward until vertical. | .
(3) If, while advancing the sheeting, the pressure
becomes so great as to spring it, a false frame must be

204

used (figs. 104 and 105). "This consists of a cap, a sill,
and two posts connected by mortises and tenons. Posts
have tenons апа cap and sil] have mortises at each end.
The cap may be rounded on top and, for facility in set-

Z'ROOF SHEETING

(ШҮ |

ТЕ
KS Set
шаг
эг
ي‎
Imi

& =
—

—

PLAN
Figure 102. Wall and roof sheeting showing wedges.

ting up and removing, its mortises are longer than the
width of the tenons. The latter are held in place by
key wedges when the frame is in position (fig. 105).
The false frame is usually made the same height as the
common frames, and wider by twice the thickness of

566397^—44 —-14 205

the sheeting. In using this frame, the sill is placed ac-
curately in position a half-interval in advance, posts
are set up, and the cap placed upon them and wedged.

4X6' CAP
TOP EDGE ROUNDED
ду Sy

2"ROOF SHEETING 3x6" BRIDGE

COMMONS
SS GALLERY

WAR

CEO

TAS

4'x4"POST
OUTSIDE EDGE

Figure 104. Details of construction using false frame,

The whole frame is then raised about 2 inches by driv-
ing wedges under the sill, and is secured by battens (fig.
105.) The sheeting now rests directly upon the cap aud
posts, and has enough slant to clear the next frame by its
own thickness. The next frame is set up, wedges driven
under the sheeting. and the false frame is removed.

206

(4) In loose, caving ground, when pressure on the
Sheeting is too great for driving, it is relieved by the use

КІГІТТІ

А!

PERSPECTIVE VIEW
(SHOWING FALSE FRAME IN PLACE)

5ЕС2А-4 ELEVATION

NOTE: DETAIL
DUTSIDE EDGES DF CAP OF MORTISE а ТЕМОМ JOINT
AND POST TO BE ROUNDED.

Figure 105. Perspective view and detail of false frame.

of bridges (fig. 106). These consist of 3-inch blocks
equal in width and length to the cap or post. 'The
frame being in position, a bridge is placed over the cap,
supported at each end by wedges having the thickness of

207

the sheeting. The bridge keeps the rear sheeting from
bearing hard on the cap, thereby allowing an opening
through which the forward sheeting is driven (fig. 106).
Ав the sheeting is driven forward piece by piece, it is
sometimes necessary to pick materia] away from the
point of each board. In this manner the sheeting 15 ad-

l'xe"
SPREADER
STANDARD
WEDGE

234"
TEMPORARY
BATTEN

Figure 106. Isometric view showing use of bridge.

vanced to its final position. "Тһе next frame is blocked
into position, and the same process repeated. When
necessary to hold up the sheeting while placing the next
frame, a false frame, as described above, or posts and
headboard, may be put in place, to be removed when the
next permanent frame is placed. Side sheeting is
driven as for roof sheeting under similar greund condi-
tions. | |

(5) To drive the gallery in very loose soil, a shield
(fig. 107) may be used to prevent earth in front and
above from caving into the gallery. When the excava-

208

tion at the top of the gallery has advanced as far as
possible without causing caving to extend beyond the
top sheeting, a piece of plank a foot wide and equal in
length to the width of the gallery is placed directly
under the top sheeting against the face of the excavation
(fig. 107), and held in place at its ends by braces secured

BRIOGE

2^xl0"x 3-6" 2" RODF SHEETING
STRUTS
Еа s —
Ш rr—————— |7]
Ë | Z | пе ЕР 1 FACSE
COMMON || : - 71 БЕ FRAME
GALLERY FRAME А | |} CF
i pi ) 1 т] Esa А
і 2'kt0"x4- Q'
ШЕ. RI 5-1 ГО SHELD BOARDS
TEMPORARY "Un E 7) Fe
d Эш» Н.
| ёо ЕТ: nen
о | J НЕГО BAT TENS
= Ж. =) Ë
о ЦЕ

PERSPECTIVE VIEW
(SHOWING SHIELD IN PLACE }

g'x4'x5

х4"х 5-0 2"х 4" BRACE
TEMPORARY BATTENS

2"x4^x4'-0
LEER SHELO BATTENS

3x6" x7 O"
BRIDGE
PLAN
Figure 107. Use of shield in driving sheeting in loose, caving
soil.

209

to the gallery lining. Earth 1s removed until a second
plank of the shield can be placed, in the same way, un-
der the first one. This is continued until the entire
face is covered, The top and side sheeting is driven
forward, the top plank of the shield is removed, earth
is excavated, and the plank placed ahead, after which
each plank in turn is removed and placed ahead.

87. CHANGE OF SLOPE. То pass from a horizontal
to an ascending gallery (fig. 108) the top sheeting is
given the proper angle by holding down its back end
with a piece of scantling placed across the gallery, and
the side sheeting is given the proper inclination.
Trenches are cut in the bottom of the gallery for the
lower pieces, if necessary. In passing from a horizontal
to a descending gallery (fig. 117), the roof may be car-
ried forward horizontally and the floor given the desired
pitch by increasing the height of successive frames until
enough headroom is obtained to allow inserting the
top sheeting for the descending gallery at the proper
height and in the new direction. The frame at this
point is mede with a cap upon which sheeting rests
directly, and a second crosspiece below it, serving as a
cap for the descending gallery. From this point for-
ward, frames may be set at right angles to the axis of
the gallery. If the descending gallery is very steep,
and the horizontal pressure of the soil is great, it may
be necessary to strengthen the posts of the last two or
three vertical frames by crosspieces near their upper
ends.

88. CHANGING DIRECTION HORIZONTALLY. a.
In changing direction horizontally with frames and
Sheeting, if the soil will stand unsupported for a dis-

210

tance of one frame interval, 16 is only necessary to place
one or more frames at an angle until the desired change
of direction is gained. Sheeting on the outside is

2"ROOF SHEETING

SECTION THRU ASCENDING GALLERY

2"ROOF SHEETING
ЕТ у N T
еа STE ач ee

TUS
Pg

SECTION THRU DESCENDING GALLERY

Figure 108. Details of construction of ascending and decend-
ing galleries,

placed by running the forward end past the frame and
then inserting the rear end behind the last section of
sheeting (fig. 109). А short section of gallery may

211

be put in to reduce the amount of work (fig. 109).
Frames with extra long caps and sills are required, and
the last one used is given an extra post on the inside
to take sheeting in the new direction.

b. For abrupt changes of direction of large gal-
leries, dig in the original direction past the turning
point and then start the branch gallery in the new

212

direction. (See fig. 110.) 'The interval between the
frames of the gallery of departure at the place of de-
parture must be great enough to admit between them a
frame and the side sheeting of the branch.

e. If the branch is oblique to the main gallery, its
width measured along the gallery of departure may be

u! 4
T
|| < RECTANGULAR BRANCH

I
|
L

=т=т” 121201 GALLERY ОР
Met SIZ ——|— DEPARTURE

GALLERY OF
== DEPARTURE

DBLIQUE BRANCH
| FROM RECTANGULAR
SS BRANCH

Figure 110. Breaking out branches.

greater than that normally between the frames of the
gallery of departure. In this case a short rectangular
branch is first broken out from the side of the gallery of
departure and the new gallery is broken out from the
side of this short branch. The first frame of an oblique
branch should be so set that sides of the posts are parallel
to side walls of the branch, thus giving good bearing
to the side sheeting.

213

d. The floor of a branch is started at the level of the
floor of the gallery of departure. In soil which will
stand for a short time without support, the first frame
may be set up entirely outside the gallery of departure
and may be the same height in the clear as this gallery.
However, when side sheeting is required in the gallery
of departure, the first frame of the branch must be set |
up against this sheeting in the interval between posts.
This makes the clear height of the branch at this frame
less than that of the gallery of departure by a little
more than the thickness of the sheeting. When the
first frame of the branch is set against the sheeting of
the gallery of departure, the sheeting may be pulled
or cut away to permit excavatiori, in either case begin-
ning with the top plank.

89. CHAMBERS. In excavating a wide chamber,
care must be taken to prevent earth from falling from
the roof, Excavation of the entire width of the
chamber at the same time should not be attempted.
Until the roof sheeting can be placed, the roof is sup-
ported by an earth column left standing in the chamber,
and excavation for the side sheeting and next frame is
made around this column. The earth column is gradu-
ally removed as the roof sheeting is placed.

90. LINES AND GRADES. a: Line. In timber con-
struction, a string stretched along shallow saw cuts in
the centers of caps and sills is the simplest method of
maintaining straight lines. Plumb bobs hung from
nails in the center of caps are used for lining by eye.
Sills are leveled and posts plumbed, while the занал or
case is being lined and blocked into place.

b. Grades. The minimum grade that will insure
drainage in galleries and chambers is about 1 foot per

214

100 feet (1 percent). Uniform grades are difficult to
maintain without a level and a grade board. А соп-
venient size of grade board 15 made from a straight-edge
piece of 115-by-6-ineh lumber, 6 to 12 feet long, with а
small cleat nailed on one end. The cleat is of such
thickness that, when the board is placed on а surface
with a carpenter's level on top, the desired grade is
obtained when the level bubble is centered.

91. PLANS AND LAY-OUT. а. Plans. Before start-
ing work, location sketches showing over-all dimen-
sions are necessary so the proper material may be
ordered or prepared.

b. Lay-ont. Work is simplified if the shelter is
placed so that all entrances are perpendicular to the
center line of the chamber. "The chamber is built so
that its longest dimension is perpendicular to the prob-
able direction of enemy fire. Lay a base line parallel
to the long axis of the chamber, and mark this line so
that it can be relaid easily. should it be destroyed. Mark
the center lines of the entrances on the base line, and
from each side of the mark, at a distance equal to one-
half the outside width of the entrance, erect perpendicu-
lar lines to points where the first frames are to be placed.
Perpendiculars to the ends of a frame must be of equal
length, so that the first frames will be set parallel to
the baseline. It,is important that these first frames be
set aceurately. Тһе horizontal distance of each frame
from the base line and the difference in elevation between
the various frames must be determined, usually with
a carpenter's level and square. The axis of incline
must be carried in a plane perpendicular to the base
line, usually by sighting along the sides of the incline.

215

92. RATE OF WORK. For calculating the size of
working parties and the rate of work (including tim-
bering, but exclusive of disposal of spoil on the surface),
the following figures may be accepted as average:

a. Inclines. Common gallery, size 6 feet 4 inches by
3 feet, inside clear dimensions. One relief includes:
one man picking and timbering; one man filling sand-
bags and timbering; and one man carrying for each 10
feet from working face to entrance. Average progress
for each 8-hour shift, about 3 feet 6 inches.

b. Passages. Galleries, common gallery size: work-
ing party the same as for inclines; average progress
for each 8-hour shift, about 4 feet.

e. Chambers. (1) Chamber gallery size, 6 feet 4
inches by 8 feet 6 inches, inside clear dimensions: two
men picking; four men fillmg sandbags and timbering,
who relieve pickmen as they tire; add two men for each
10 feet of carry; average progress for each 8-hour shift,
about 3 feet.

(2) Great gallery size, 6 feet 4 inches by 6 feet 6
inches, inside clear dimensions: working party same
as for chamber gallery; average progress for each 8-
hour shift, about 3 feet 6 inches.

d. Surface carrying party. Опе man can carry
100 sandbags for 200 feet in 8 hours under ordinary
trench conditions. One bag equals 0.5 cubic foot or
about 50 pounds,

216

APPENDIX I
GLOSSARY OF TERMS

The terms used in this manual are defined as follows:

Airlock. An intermediate chamber, with а gasproof
curtain at each end, located between the outside and in-
side of a shelter (fig. 70).

Angle of repose. The steepest slope at which a heap
of material, such as earth, will stand without sliding.

Batten. А strip of wood used for nailing across two
other pieces to hold them together, for covering a crack,
or for holding tarpaper against wood.

Bay. The straight section of a trench between two
bends.

Brush revetment. Cut brush held against a wall by
pickets (fig. 14).

Brushwood hurdle. A woven rectangle of brush-
wood used as a revetment (fig. 13).

Burster blocks. Prefabricated, reinforced concrete
blocks so designed that a number can be wired together
to form a burster course (fig. 73).

Chamber. An enlarged room in a shelter, used as a
bunkroom or for other purposes.

Choked end. The end of a filled sandbag that has
been tied with twine.

Crutch. An upright piece of timber with a cross
plece at the top, used while driving a gallery as sup-
port for the caps until the posts for that purpose can
be inserted (fig. 99).

Dannert barbed-wire concertina, Prefabricated
wire-roll obstacle made of high-strength-steel barbed
wire.

217

Drainage lines. Channels or low lines of the terrain
in which water flows either continuously or intermit-
tently.

Flume. Ап open wooden channel conveying water.

Gauge rod. А. stick, cut to a definite length and
marked at certain intervals, used for checking the size
of the excavation while driving galleries.

Gallery cases. Prefabricated framework used to line
galleries.

Gallery frames. Framework which holds in place
sheeting used to line galleries.

Grenade pit. А pit, usually at the end of an incline,
to catch hand grenades and limit the effects of their
explosion (fig. 98).

Header. Sandbag, stone, or brick laid with its long
dimensions at right angles to the face of a wall.

Impact velocity. Speed of a projectile at the mo-
ment of striking.

Incline. An ascending or descending gallery (fig.
98).

Man-hour. The amount of work an average man can
do in one hour,

Outrigger trench, Special excavations required for
the outriggers of the 90-mm antiaircraft gun.

Perforation, Тһе passage of a missile completely
through an object.

Picket. A stake of wood, wrought iron, or steel used
in constructing revetments and wire obstacles.

Rabbet. A groove ог notch cut in one timber mem-
ber to aid in joining it to another.

Scabbing. 'The breaking off of fragments on the
inside of & wall of hard materia] due to the impact or
explosion of a projectile on the outside.

218

Shaft. А vertical opening of limited cross section
used for ventilating underground shelters and as an
emergency exit.

Shaft cases. Standard size frameworks used to line
a shaft.

Shaft frames. Frameworks holding in place sheet-
ing used to line a shaft.

Sheeting. Planks used to line a gallery or shaft.

Slope. 'The measure of an incline, wall, or ramp in
terms of the ratio of vertical rise in a given horizontal
distance to that horizontal distance.

Special trench. A trench, 2 feet wide or less and
from 3 to 5 feet deep, used primarily for protection of
personnel at artillery and rear iustallations (fig. 39).

Stabilized soil. Soil hardened by addition of a binder
such as cement.

Standard trench. Trench of uniform cross section
that ean be used either as a fire or communication trench
(fig. 400) and (2)).

Streicher. Sandbag laid with its long dimension
parallel to the face of a wall.

Sump. A pit in the bottom of an excavation to col-
lect drain water so it can be pumped or bailed out.

Thin natural screen. Natural growth left in front
of entrenchments and emplacements to aid in conceal-
ing them.

Trail support. A log or other object placed under a.
trai] spade of an artillery piece to provide additional
resistance to recoil (fig. 59).

Trench boards. Flooring used in trenches (fig. 41).

219

APPENDIX П

EFFECTS OF BOMBS AND
PROJECTILES

1. PURPOSE. Fortifications are designed primarily
to withstand effects of bombs and projectiles. Тһе de-
gree of protection provided is dependent upon the time,
materials, and tools available and the types of bombs
and projectiles likely to be used. This appendix is a
guide to be followed in designing protective walls and
covers of fortifications. It describes the effects of vari-
ous classes of bombs and projectiles, and indicates the
thickness of different materials required to protect
against these effects.

2. CLASSES OF EFFECTS. The action of bombs
and projectiles striking their targets may be considered
under the following:

a. Explosion upon impact. Bombs and projectiles
that contain explosives and have instantaneous fuzes
explode upon striking any surface, and are used prima-
rily against personnel above ground level. Walls and
cover thick enough to resist blast and penetration of :
fragments give adequate protection.

b. Penetration. Small arms and other direct-fire
weapons whose projectiles do not contain an explosive
charge depend upon perforation and scabbing for their
effect. Тһе depth of penetration depends upon striking
velocity, size, shape, and weight of the projectiles,
and upon the material they strike. Adequate protec-
tion сап be obtained by getting below ground level ог
behind walls thick enough to resist penetration.

220

c. Penetration and explosion. Bombs and explo-
sive projectiles equipped with delayed-action fuzes com-
bine the effects of penetration and rupture from
explosion. Adequate protection requires cover and
walls thick enough to resist penetration plus rupture and
floors thick enough to resist rüpture. :

3. PROTECTIVE THICKNESS. Protective thickness
is that thickness of a material which is required to pro-
tect against any or all of the effects described in para-
graph 9. Until quite recently there had been a scarcity
of data on protective thickness. An extensive pro-
gram of tests is being followed, but results are not avail-
able for inclusion in this manual. The figures given
in tables XXII, X XIII, and XXIV are approximations
and are not necessarily minimum safe figures, They
are based upon empirical formulas checked against such
tests as previously were made, and contain a factor of
safety large enough to give the indicated protection
nnder ordinary conditions. Figures are given for
tvpical soils and other materials found under field
conditions.

566397? —44-—185 221

"раолојипох Áj[G1njonqggg | 8 $ |46 е (ИТ I
"SITE ододоцог КгвшраО 49 ИФ Р “е 5 АТ
Бери Би 20-90 c
о ~ ГЭ
z S| By ob
| Ë М ві веч
БЕРБЕ! eee
SE 55 4” > “> L9
ue 43134 ЧЧ ЧЕ"
ав | ЗБ | 29 | 72 | “25 | 48
a 8 اچ‎ я) s ДЕ
$| 8| & 8| E[*8

и q77opt--- "e(poo1oj
…[truncated]

Related across Profoundd

Oregon Climate Docs

Grants Pass — Sustainability and Energy Action Plan p.143
APPENDIX IV: METHODOLOGY GRANTS PASS SUSTAINABILITY AND ENERGY ACTION PLAN PROJECT IMPACTS Emissions estimates were refined using the expected impact of individual projects. To do this, updated electricity or fuel usage…
Grants Pass — Sustainability and Energy Action Plan p.144
APPENDIX IV: METHODOLOGY GRANTS PASS SUSTAINABILITY AND ENERGY ACTION PLAN PROJECT IMPACTS (continued) BE-6-1, BE -6-2, BE -6-3: Two brownfield solar panel projects are assumed to be operational on the Foothill Landfill…
Ashland — Climate and Energy Action Plan (CEAP) p.137
CLIMATE TRENDS & PRO JECTIONS | CITY OF ASHLAND, OREGON | FINAL REPORT | 8 (RCP4.5) and high (RCP8.5) emissions scenarios. Projections for each metric are discussed further in the following sections with a focus on …

WEF Publications

Chief Economists Outlook January 2026 p.31
49. The Economist. (2025, 27 November). American consumers are miserable. But they keep spending. The Economist. https://www.economist.com/business/2025/11/27/american-consumers-are-miserable-but-they-keep-spending; Un…
Global Risks Report 2026 p.2
Contents Preface Overview of methodology Key findings Chapter 1: Global Risks 2026-2036: The Age of Competition 1.1 The world in 2026: on a precipice 1.2 The path to 2028: compounding risks 1.3 The path to 2036: over the…
The Global Risks Report 2024 p.80
10000-chip-powering-the-race-for-ai-.html; Nellis, Stephen and Max A. Cherney, “US curbs AI chip exports from Nvidia and AMD to some Middle East countries”, Reuters, 1 September 2023, https://www.reuters.com/technology/…

Epstein Files

EFTA00277580 — • e US Department MAJOR REPAIR AND ALTERATION Of Transportation
• e US Department MAJOR REPAIR AND ALTERATION Of Transportation Federal (Airframe, Powerplant, Propeller, or Appliance) Aviation Administration Form Approved OMB No. 2120-0020 For FAA Use Only Office Identification So- r…
EFTA01224242 — C-CURE 9000
C-CURE 9000 Version 2.30 Galaxy Controller Integration Guide REVISION CO SOFTWARE HOUSE From Tyco Security Products 76 Technology Park Drive Westford. MA 01886-3140 Fax: 978-577-4392 Phone: 978-577-4000 EFTA01224242 C•CU…
EFTA01225244 — SOFTWARE HOUSE From Tyco Security Products
SOFTWARE HOUSE From Tyco Security Products C•CURE 9000 Version 2.50 Card Formats and Smart Card Keys User Guide REVISION HO UM-253 110 EFTA01225244 C•CURE and Software House are registered trademarks of Tyco Security Pro…

Federal Writers' Project

[Andrew Johnson]
k?4.4_,C4 Forms to be /iMed out for Each Interview FOLKLORE NEW YORK STATE New York City NAME OF WORKER FORMA Circumstances of Interview Levi C. Hubert ADDRESS 353 West 118th St. Manhattan. DATE November 28, 1938 SMUT II…
[Spark, The Mighty Man]
7F7 V44-erwiteArt..... SPARKS, THE MIGHTY MAN January 4, 1921 (My 19th birthday) went to the recruiting station on Bast 23rd St. and wenlisted in the United States Marine Corps, for a period of four years. Tomorrow I go …
[Reports]
WORKS PROGRESS ADMINISTRATION OF NORTH CAROLINA Federal Writers' Project Chapel Hill, N. C. October 12, 1938 Mr. Henry G. Alsberg Federal Writers' Project gth and G Streets, N. W. Washington, D. C. Dear Mr. Alsberg: ille…