FM 90-7
Scatterable Mines
mines is a complex obstacle. The RC
SCATMINEs are laid without regard to clas-
requires that the enemy employ its mechan-
sical pattern and are delivered by aircraft,
ical bridging or blade-breaching assets,
helicopter, artillery, missile, or ground dis-
while the AT mines require that the enemy
penser. SCATMINEs provide the maneuver
use a mine-breaching asset. Together, the
RCs and mines create a better obstacle. The
commander a flexible, responsive, and lethal
key to creating effective complex obstacles is
mine-laying capability to affect the enemy’s
knowing the quantity and capability of the
ability to maneuver. All US SCATMINEs
enemy’s breaching assets.
have a limited active life and self-destruct at
a preset time. The duration of the active life
A complex obstacle should affect low-density
depends on the type of mine and delivery
breaching equipment first; then it should
system.
affect more common breaching equipment.
For example, if the enemy has nine mine
SCATMINEs are not an obstacle cure-all for
plows and three blade tanks, the unit can
inadequate tactical planning. Their use
use an AD and mines to force the enemy to
requires extensive coordination, integra-
use both breaching assets. This increases
tion, and control. Indiscriminate use of
the time required to breach. Moreover, by
SCATMINEs causes a rapid depletion of
putting the AD before the mines, the enemy
valuable assets. More importantly, the
must use its lowest density breaching equip-
poorly planned use of SCATMINEs can
ment first. If friendly forces destroy the
impede friendly movement and cause fratri-
blade tanks, they reduce the probability of
cide. For more detailed information on
the enemy breaching the complex obstacle.
SCATMINEs and systems, refer to Part
Another example of complex obstacles is
Two, FM 20-32.
using AP mines, triple standard concertina,
tanglefoot, and AT mines. The wire and
IMPROVISED OBSTACLES
AP mines strip the enemy’s dismounted
infantry away from assaulting tanks. This
Soldiers and leaders design improvised
makes both more vulnerable and enables
obstacles with imagination and ingenuity
the defending force to concentrate on one
when using available materials and other
type of threat. The AT mines prevent
resources. Possible improvised obstacles
armored vehicles from dashing through the
include the following:
wire unimpeded.
Rubbled masonry buildings.
Controlled fires.
PHONY OBSTACLES
Flooded areas created by opening flood-
gates or breaching levees.
Phony obstacles play a key role in obstacle
protection by helping hide a unit’s actual
Damaged vehicle hulks used as road-
obstacles from the enemy. They can also
blocks.
help a unit compensate for shortages of
obstacle resources. A unit can mix actual
COMPLEX OBSTACLES
obstacles with phony obstacles within an
Units can create complex obstacles to
obstacle group. Naturally, this implies risk,
improve the effectiveness of obstacle groups.
and commanders must ensure that they con-
Complex obstacles are a combination of
sider the risk of using phony obstacles.
different types of individual obstacles.
Commanders must also ensure that the
For example, an RC reinforced with AT
emplacing unit creates a phony obstacle
A-6 Individual Obstacles
FM 90-7
that will have the desired result on the
ARMOR THREAT
enemy. An example is a shallow excavation
Units may need to design minefield for
combined with a loose soil berm to simulate
armor threats other than soviet-style forces.
an AD. Another technique is to use mine-
The next few paragraphs describe some con-
field markings where there are no mine-
siderations for designing minefield based
field. To be successful, this technique
on an enemy with armor companies of 12 to
normally requires that the unit establish a
18 combat vehicles. These are minefield
precedent. Highly visible minefield mark-
that a unit can use as building blocks for
ings in a disrupt obstacle group in forward
obstacle groups in mostly open terrain.
areas provide a visual cue to the enemy con-
cerning minefield. Using the same mark-
Width
ings without minefield in a fix obstacle
group may cause the enemy to assume that
An enemy armored company of 12 to 18 com-
bat vehicles will have a probable frontage of
there is an actual minefield where none
500 meters when deployed. To affect the
exists.
enemy, half the enemy company frontage
(250 meters) should encounter the mine-
INDIVIDUAL OBSTACLE DESIGNS
field. An individual obstacle of 250 meters
frontage is an appropriate-size building
The remainder of this appendix provides
block.
guidelines for individual obstacles. Units use
individual obstacles as building blocks for
Depth
obstacle groups. Standard obstacles allow
rapid estimating for resourcing (time, man-
Minefields must have enough depth to sup-
power, equipment, and materials) that is
port the obstacle effect based on the enemy’s
critical in making the force’s obstacle effort
breaching capability. If the commander
wants a disrupt or fix effect, the minefield
effective, efficient, and timely. They allow
should require the enemy to expend at least
units to train on the installation of individ-
one breaching asset (for example, 100
ual obstacles as drills.
meters if the enemy has a mine-clearing line
FMs 5-34, 5-102, and 20-32 provide details charge (MICLIC)). For the turn-and-block
on specific standard obstacles.
effect, the depth should increase to force the
enemy to expend more breaching assets. For
These standard obstacles are not the only
an enemy not equipped with line charges,
types of obstacles that units should consider.
the depth can decrease. If the enemy has no
Instead, units should consider modifying
mechanical breaching assets, the depth can
standard obstacles or creating their own
decrease even further.
standard obstacles based on METT-T and
other resource availability. For example, the
Antitank Mines
standard minefield in FM 20-32 are focused on a soviet-style tank and motorized infan-The two options are track-width and full-
try threat. These minefield may not be
width fuzed AT mines. Compared to the full-
appropriate for a mixed force of light infan-
width fuzed mines, track-width fuzed mines
try and tanks.
have a lower probability of encounter.
Track-width fuzed mines require a den-
The following paragraphs provide some
sity of 1.0 per linear meter of front; how-
basics for designing minefield based on the
ever, adding one row of full-width fuzed
type of threat.
mines can reduce the resources required
Individual Obstacles A-7
FM 90-7
while increasing the probability of encounter
formation, it has a frontage of 40 to 200
for the minefield. This results in one row of
meters. Using 200 meters as the enemy’s
full-width fuzed mines and two rows of
maximum frontage, the standard minefield
track-width fuzed mines.
must target half of its frontage (100 meters).
Camouflaging the mines and total pattern
Antipersonnel Mines
aids tremendously in increasing the effec-
tiveness of the disrupt and fix minefield.
The minefield focuses on the mounted
threat, so if the enemy has mounted breach-
ing assets, AP mines normally will not make
Depth
much of a difference. However, if the enemy
A 45-meter depth complicates a light infan-
lacks mechanical breaching assets, adding
try’s breaching attempt. A light force
AP mines can help prevent dismounted
employs grapnel hooks, hand-placed explo-
breaching.
sives, bangalore torpedoes, and portable
explosive line charges. The 45-meter depth
Antihandling Devices
requires multiple uses of those assets.
The emplacing unit determines the require-
ment for AHDs based on the threat. Nor-
Antitank Mines
mally, units use AHDs only if they expect
The minefield focuses on the dismounted
covert or other dismounted breaching
threat. Normally, AT mines are useful only
attempts.
if the enemy has vehicles.
Irregular Outer Edges (IOEs)
Antipersonnel Mines
The purpose of IOEs is to confuse the enemy
The M16A1 AP mine provides the best mix
about the orientation of the minefield and to
of lethality and density for the disrupt or fix
increase the probability of an encounter.
minefield. The M18 Claymore mine is
There may be cases where an IOE is desir-
able, such as a fix or block effect. The IOE
another choice. The M14 AP can be used;
does not have to be part of the standard
however, it requires a much higher linear
minefield.
density.
LIGHT THREAT
Antihandling Devices
Designing standard minefield to achieve a
The emplacing unit determines the require-
specific obstacle effect against a light force is ment for AHDs based on the threat. At least
a unique challenge. There are no strict doc-
some mines, especially those on the leading
trinal frontages associated with an enemy
edge of the minefield, should have AHDs.
light infantry company; however, a typical
march formation for a dismounted infantry
company has a frontage of 40 to 200 meters.
Irregular Outer Edges
The following paragraphs describe consider-
The IOE’s purpose is to confuse the enemy
ations for designing standard minefield for
about the orientation of the minefield and to
a light threat.
increase the enemy’s probability of encoun-
ter. Use of the IOE is normal only in rela-
Width
tively open terrain.
An enemy infantry company typically con-
Leaders should not limit their view of
sists of three platoons. In march (column)
reinforcing obstacles only to minefield.
A-8 Individual Obstacles
FM 90-7
Note that throughout this manual, individ-
possible obstacle arrays to support specific
ual obstacles are depicted as shaded rectan-
effects.
gles, unless a specific variety of obstacle is
It also is important to fit standard obstacles
discussed. Those shaded rectangles repre-
to the terrain. For example, units do not
sent individual obstacles. The actual type of
need to lay row minefield in a straight line.
individual obstacle depends on METT-T,
They must array the obstacle based on the
Leaders should consider the full range of
weapon systems and the terrain to achieve a
individual obstacle varieties when installing
specific effect. Figures A-6 through A-8,
individual obstacles. Leaders have as many
pages A-10 and A-11, show some examples
options as their imaginations allow.
of how to use standard obstacles in different
arrays to achieve an obstacle effect.
Standard obstacles enable planners at all
INDIVIDUAL OBSTACLE ARRAY
echelons to estimate resource requirements
based on linear obstacle requirements. Like
The standard row minefield in FM 20-32
all planning factors, they provide a base for
are classified as disrupt, fix, turn, and block.
estimating requirements and must be
Although these minefield are classified that
adjusted to the factors of METT-T. Produc-
way, the array of individual obstacles is
tion rates decrease because of limited visi-
what supports the obstacle effect. Units may
bility; nuclear, biological, and chemical
use any of these minefield or other obstacles
(NBC) threat environment; reduced troop
to achieve an obstacle effect if the array
strength or proficiency; and adverse weather
supports the desired effect. Figure A-5 shows
conditions.
Individual Obstacles A-9
FM 90-7
A-10 Individual Obstacles
FM 90-7
Individual Obstacles A-11
FM 90-7
Appendix B
Obstacle Numbering, Reporting,
Recording, and Tracking
This appendix describes the obstacle num-
The designation for the HQ is a letter fol-
bering system and the requirements for
lowed by three numbers. For example, XVII
obstacle reporting and recording.
Corps is shown as Z017; 23d Armored Divi-
sion is shown as A023; and the 103d Air-
borne Division is shown as I103.
OBSTACLE NUMBERING
Obstacle zones are indicated by a single let-
The obstacle numbering system shown in
ter starting with “A” and continuing in
Table B-1, page B-2, consists of 11 alphanu-sequence. Obstacle Zone A in XVII Corps is
meric characters and an obstacle status sym-
distinguished from Obstacle Zone A in 77th
bol character. This number is compatible
ID by the HQ designation (Z017-A versus
with the Tactical Engineer Command and
1077-A). The second obstacle zone in 77th
Control System (TECCS) that augments the
ID would be Obstacle Zone B (I077-B).
Maneuver Control System (MCS). An obsta-
Obstacle belts are indicated with a single
cle number provides the following informa-
digit following the obstacle zone designator
tion concerning an individual obstacle:
starting with “l” and continuing in
HQ that established the obstacle zone in
sequence. For example, the first obstacle
which the obstacle is located.
belt in Obstacle Zone C of the 5th Cavalry
Obstacle zone designation (if any).
Division is shown as C005-C1.
Obstacle belt designation within the
Obstacle groups are depicted by a single let-
obstacle zone (if any).
ter starting with “A” and continuing in
Obstacle group designation within the
sequence. For example, the first obstacle
obstacle belt.
group in Obstacle Belt 2 of Obstacle Zone B
Individual obstacle type.
in the 77th ID is I077-B2A.
Individual obstacle number.
The individual obstacle type is expressed by
Obstacle status.
one or two letters as shown in Table B-2,
If units do not use obstacle zones and belts, pages B-3 and B-4. For example, AD obsta-or if the HQ directs obstacles outside an
cles in I077-B2A are shown as I077-B2A-
obstacle zone or belt, an asterisk is used in AD. Standard block minefield in the same place of the obstacle zone or belt designator.
group are shown as I077-B2A-MB.
Obstacle Numbering, Reporting, Recording, and Tracking B-1
FM 90-7
The individual obstacles in an obstacle group The obstacle status symbol is the last charac-are indicated by a two-digit number starting ter of the obstacle number. The status sym-with “01” and continuing in sequence. There- bol shows whether the obstacle is—
fore, the first block minefield in obstacle group Planned (/)
I077-B2A is I077-B2A-MB01. The second
Being prepared (-).
block minefield in the group is I077-B2A-
Prepared, but not executed (+).
MB02. If the obstacle group consists of a sin-
Executed or completed (x).
gle obstacle, it is also shown as I077-B2A-
MB01.
For example, if the first of the block mine-
field discussed in the previous paragraph is
If the corps or division orders the emplace- completed, the obstacle number is I077-B2A-ment of an obstacle group outside an obstacle MB01X. If the corps reserve obstacle dis-zone, then there is no obstacle zone or belt cussed in the previous paragraph is pre-designator. Instead, units replace the obstacle pared, the obstacle number is Z017-**A-zone and belt designators with asterisks (*). BA01(+).
For example, if XVII Corps orders the demoli-
tion of a bridge (abutment only) as a corps Obstacle numbering for protective obstacles reserve obstacle and this is the first such may require procedures that vary slightly obstacle, then the obstacle is indicated as from those described. Units should report Z017-**A-BA01. If the 1st Brigade, 77th ID, protective obstacles; however, identifying the orders an ADAM/RAAM scatterable minefield individual obstacles is difficult using the in Obstacle Zone B and outside all obstacle obstacle numbering guidelines without guid-belts, the designation is I077-B*A-SF01.
ance from the higher HQ. A technique is for
B-2 Obstacle Numbering, Reporting, Recording, and Tracking C1, FM 90-7
Table B-2. Obstacle type abbreviations.
M—Minefield/Munition Field
W—Wire Obstacle
MB
Block
WA
Double-apron
MC
Chemical
WC
Concertina
MD
Disrupt
WF
Tanglefoot
MF
Fix
WG
General-purpose, barbed tape
MH
Hasty protective
WN
Nonstandard
MN
Nonstandard
WR
Roadblock
MO
Point
WT
Triple-standard
MP
Protective
S—Scatterable Minefield/Munition Field
MQ
Nuisance
SB
Gator
MS
Standard-pattern
SF
ADAM and RAAM
MT
Turn
SM
MOPMS
MU
Dummy/decoy
SV
Volcano
A—Miscellaneous
SW
Scatterable mines (generic)
AB
Abatis
H—Hand-Emplaced Munitions
AC
Chemical by explosives
HC
Claymore
AD
AT ditch
HH
Hornet/WAM
AF
Thermobaric or flame
HO
Other
AH
Log hurdle
HS
SLAM
AL
Log crib or log obstacle
I—Improvised Explosive Devices
AM
Movable obstacle (car, bus)
ID
Directional, special-purpose explosive
hazard
AN
Expedient nonstandard obstacle
AP
Post obstacle (hedgehog, tetrahedron) IO
Omnidirectional, special-purpose
explosive hazard
AR
Rubble
Obstacle Numbering, Reporting, Recording, and Tracking B-3
C1, FM 90-7
Table B-2. Obstacle type abbreviations (continued).
AT
AT ditch with AT mines
B—Bridge Demolition
BA
Abutment
AW
Earthwork
(berms, parapets, dunes, pits)
BC
Abutment and span
T—Booby Traps
BS
Span
TA
Booby-trapped area
R—Road Crater
TB
Booby-trapped bodies
RD
Deliberate
TE
Booby-trapped equipment
RH
Hasty
TM
Booby-trapped material
RM
Mined
U—Unexploded Ordnance
TP
Booby-trapped passage/
confined space
UC
Chemical UXO hazard area
TS
Booby-trapped structure
UH
UXO hazard area
TV
Booby-trapped vehicle
UN
Nuclear hazard area
units to assign default obstacle zone,
linked directly to specific company teams.
belt, and group designators for protective ob-
The first protective minefield that Team A,
stacles outside control measures. For exam-
TF 1-2 emplaces has the obstacle number
ple, 77th ID assigns W, X, Y, and Z (it is
I077-W1A-MP01X.
unlikely that the division will ever have
enough actual obstacle zones to require
OBSTACLE REPORTING
these letters) as default obstacle zone desig-
nators for subordinate units as follows:
An obstacl