BATTLEFIELD CALCULATIONS
Section II . SEEING, HITTING, AND KILLING
8-4 PLANNING FACTORS
a. The ability to observe is determined by:
(1) The capability and range of the sensor, human eye, optics, etc.
(2) The line of sight based on the terrain.
(3) Visibility based on day or night, weather, and battlefield obscuration.
b. The probability of hit (Ph) is based on:
(1) The capability of the weapon system.
(2) The accuracy of the round.
(3) The range.
(4) Gunner proficiency.
(5) Target speed and exposure.
c. The probability of kill (Pk) is the probability of killing the target if it is hit based on the:
(1) Velocity and penetrating power of the round at a given range.
(2) Angle of impact.
d. Ammunition expenditure is forecast by considering the:
(1) Number of targets.
(2) Ph and Pk.
Example: How many rounds are need to kill 10 targets if the probability of hitting the target is 90 percent and the probability of killing (if hit) is 80 percent.
10 kills = (# of rounds fired) x ( # of targets hit / # of rounds fired) x ( # of targets killed / # of targets hit)
10 kills = ( # of rounds fired ) x (.9 hits/ round) x (.8 kills/ hit)
# of rounds fired = (10 kills ) / (.72 kills / round fired ) = 10 / .72 = 13.9
The shooter willo require 14 rounds to kill the 10 targets.
8-5. CONSIDERATIONS
Several considerations combine to make lethal frontal engagements of enemy tanks unrealistic beyond 2,000 meters. Because of the approach to armor design, enemy tanks have most of their armor protection concentrated in the formal 60-degree arc of the turret. These enemy armors are difficult to penetrate frontally at any range with kinetic energy (KE) ammunition. However, the sides, top, and rear have relatively thin armor, making them vulnerable to attack from these aspects. Reactive armor has an even greater negative effect on chemical energy (CE) warheads, whether delivered by tank or missile. Although attempts to increase KE penetration capabilities against enemy armor have been fairly successful, the more modern long-rod penetrators achieve this at the expense of some delivery accuracy. Obviously, to achieve a kill, the penetration must first hit the target.
a. Range. It is possible to hit an enemy tank at 3,000 meters, but difficult to do so on the first round of firing than on successive rounds. Further, even given a hit, the Pk will be very low against turret frontal aspects. With a limited number of rounds on board a tank (40 rounds on an M1A1 tank), and the time and logistic support needed for resupply, the commander must manage resources carefully. The idea is to make every bullet count, which requires reduced engagement ranges. There is a balance. Engaging at too close a range frontally will increase Ph and Pk, but will reduce the number of targets that can be destroyed before the attacker is on the friendly unit’s position. If mission considerations take priority (for example, a delay mission), the engagement ranges may be extended at the cost of the number of kills possible before resupply is required. The ideal planning range is 1,500 meters. This can be extended with recognition of degraded Ph, degraded Pk against turret frontal armor, and reduced kills with the onboard load of ammunition. A planning range of 1,000 to 1,500 meters is appropriate if obscuration is expected.
b. Target exposure. The number of targets affects defensive operations. Defense missions imply a superiority in enemy combat vehicles. The implication for the defender is to kill enemy vehicles and to keep on killing them over a long period of time. Then, when the attacker-to-defender ratio is sufficiently reduced, at least locally, the defender must seize the initiative from the attacker. Speed of the threat attack presents problems. Speed causes more targets to be at a given point during a specific period. The counter to this must be to spread the fight through the depth of a sector. Depth in the brigade sector will normally be achieved by deploying company teams in depth within the battalion sectors. Rarely could a brigade afford to thicken the battlefield sufficiently to have battalions in depth, and there would be significant C2 problems. At the other end of the spectrum, the team commander will normally fight his team intact on one position at a time. He will not split the company team and fight platoons in depth from different positions. This does not preclude moving platoons separately from one company team position to the next. Selecting restrictive terrain with chokepoints will help regulate the flow of the attacker into the killing area. Given effective fire distribution, the defender should be able to kill at least three vehicles per defending tank against the enemy flank before the enemy can begin to return fire.
c. Fire distribution. An optimum direct-fire distribution plan would result in each target being killed only once. More targets and shooters in the fight make this increasingly difficult to achieve. It is difficult enough at platoon and company levels. A battalion EA will almost certainly result in less efficient fire distribution due to duplication, masking, dead space, and obscuration. In an ideal situation, good fire distribution should allow a defending team with terrain masking that is engaging from the flank at 1,000 to 1,500 meters to quickly destroy a reinforced threat company. If the terrain is not ideal for such close engagement, the defender must adapt these principles to the terrain for longer ranges but recognize that this will degrade visibility, C2, Ph and Pk, and favorable direct-fire combat ratios.
d. Obstacle use. An effective obstacle plan will increase target exposure times or angles of attack by slowing, stopping, or turning the enemy.
e. Areas of fire and observation. When employed in the defensive role as part of a battalion, the tank company defends a strongpoint 1,000 meters wide and 500 meters in depth. There are 300 meters between platoons. The arc of observation for a tank with a stationary turret is restricted to the gunner's and the commander's sights, an arc of 18 degrees. There are normally 150 meters between individual tanks.