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Suppression and the Efficiency of Infantry Soldiers
Dr. Eylam Gofer, Ben Levav, Yohay Gerafi
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Background Combat models tend to focus on:
The battlefield The weapons
Both factors are physical and quantifiable The soldier is less emphasized
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Background cont.
Soldiers are expected to perform different tasks on the battlefield and operate various weapons
They are also affected by:• Physiological factors• Psychological factors• Human-weapons system interface• …
Most of these influences are subjective and therefore vary from one soldier to the other
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Fear results from the
obvious threat to one’s life
Subjective and varied between soldiersIs the basis to the
phenomenon called suppression
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Suppression - Definition
Time-limited degradation of combat efficiency of a unit or an individual subjected to enemy fire
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Quantitative Approach “Macro” approach: Marshall, Wigram, and
Rowland Mainly define degradation measures to combat
efficiency We tried to use a “Micro” approach that
focuses on the soldiers activities in combat and how they are affected by suppression
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Objective Describing, Quantifying and Analyzing Fire
Suppression Effect on Infantry Soldiers in Combat
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Soldier in a “foxhole” or behind a temporary
cover
General Suppression Model
Soldier advancing
Method
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1st
2nd3rd
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Down Hill
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Scanning The Field
of Fire
Target Acquisition
Aiming Firing “BDA”
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Scanning The Field
of Fire
Target Acquisition
Aiming Firing “BDA”
1t 4t3t2t 5t
Soldier Activity Cycle: Length: Rate:
54321 tttttTw
ww T/1 Fire Rate in Training0.66( shots/sec)
Nominal Fire Rate 0.1( shots/sec)
Combat condition degradation[Rowland, 1986]
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Down Hill
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Effect of Suppression
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Scanning The Field
of Fire
Target Acquisition
Aiming Firing “BDA”
Suppressing Event
Direct Fire
Indirect Fire
Suppressing events: Time between events: Rate: Duration of suppression:
ss T/1sT
t
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Suppression Duration Approximate duration: Seconds Not deterministic, variance sources:
• Between soldiers• Between events, for the same soldier• Between the weapons or ammunition that
cause the suppression - mainly caliber Therefore we regard t as a random variable
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t~Gamma),1/|cal(
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Direct Fire Gamma Distributions
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0
0.01
0.02
0.03
0.04
0.05
0.06
משך הדיכוי מתחמושת קליעית )שניות(
תפו
פיהצ
קליע 0.5'
קליע 7.62 מ"מ
קליע 5.56 מ"מ
Suppression Duration (Seconds)
Den
sity
12.7 mm (50 cal.) 7.62 mm 5.56 mm
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General Model
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Suppression Model
The Soldier Activity CycleLength - Tw Rate - w=1/ Tw
Suppressing EventLength - Ts Rate - s=1/ Ts
The Soldier Suppressed Activity
Rate - ’w
Degradation rate
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Results Simulation:
On-going soldier activity cycle A sequence of suppressing events - each
with a random duration “Disturbing” the soldier activity cycle Measuring the activity rate with the
disturbance
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Direct Fire - Fire Rate Under Suppression
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0 0.05 0.1 0.15 0.2 0.25
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Fire Rate Enemy (shots/sec)
Fir
e R
ate
Fro
m F
oxho
le (
shot
s/se
c)
5.56 mm
7.62 mm
12.7 mm (50 cal.)
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Direct Fire - Degradation Rate)%(
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 0.02 0.04 0.06 0.08 0.1 0.12
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Fire Rate Enemy (shots/sec)
5.56 mm 7.62 mm 12.7 mm (50 cal.)
Deg
rada
tion
Rat
e(%
)
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Indirect Artillery Fire Direct fire is usually more accurate due to
range and system accuracy - It is reasonable to assume the majority of the shots fired will hit the vicinity of the post close surrounding, therefore suppressing the soldier in it
Indirect fire is statistical - Not every round will cause suppression
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Probability of Suppression [Mueller & Pietsch, 1978] - empirical study Ammunition calibers examined: 155mm, 81mm The main result: formulation of the probability of
suppression when the ammunition caliber (D) and impact distance (r) are given: P)suppression|r,D(
We have transformed that into P)suppression|R,D( R - the distance of the position from the aiming
point (assuming artillery fire CEP is 30 meters)
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02.0108exp89.0)|( 25 RRuppressionP s
81 mm
155 mm
Distance of the Artillery Aiming Point from the Post (meters)
Pro
babi
lity
of
Sup
pres
sion
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Suppression Duration [Mueller & Pietsch, 1978] give a rather low
empirically-based estimate This, we assume, is due to the absence of real
danger to the subjects during the experiment Again, based on [Rowland, 1986], it is
reasonable to assume figures are about ten times larger
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Indirect Fire - Fire Rate Under Suppression
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Position Distance From Aiming Point (meters)
Time Betweenrounds (seconds)
Position Fire Rate)shots/minute(
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Concluding Remarks The suppression model is one of the building
blocks of the methodology for comparing force configurations based on operational efficiency
The mathematical results can be, and already have been, incorporated in different models, modules and combat simulators
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Unclassified
Thank you!
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