AIR FORCE PAMPHLET 14- 210 Intelligence

Attachment 7

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Attachment 7

A7.1. Introduction. According to DIA's BDA Quick Guide (PC- 8060- 1- 96, Feb 96), collateral damage is assessed and reported during the BDA process. Broadly defined, collateral damage is unintentional damage or incidental damage affecting facilities, equipment or personnel occurring as a result of military actions directed against targeted enemy forces or facilities. Such damage can occur to friendly, neutral, and even enemy forces. During Linebacker operations over North Vietnam, for example, some incidental damage occurred from bombs falling outside target areas. Consequently, there was an effort to minimize such collateral damage to civilian facilities in populated regions. Determining collateral damage con-straints is a command responsibility. If national command or theater authorities do not predetermine con-straint levels for collateral damage, a corps or higher commander will normally be responsible for doing so.

A7.1.1. When a commander is planning strikes near his own forces, there is always some element of risk. Usually, conservative calculations will be prepared (except under emergency conditions) and will lead to minimal risks to friendly forces. Planning may also lead to maximizing collateral damage to enemy facilities near struck targets.

A7.2. Risk. A planner may accept different levels of risk when weapons are to be used near friendly forces. Risk levels are: negligible, moderate, or high (emergency).

A7. 2.1. At a negligible risk distance, troops are fairly safe. Such a risk would be considered if nuclear weapons were to be used near friendly troops. Any greater risk would be accepted only when significant advantages could be gained.

A7.2.2. At a moderate risk distance, anticipated damage levels are tolerable, or at worst a minor nui-sance. Moderate risk might be considered acceptable in close air support operations.

A7.2. 3. At an emergency risk distance, some injuries and fatalities may occur. An emergency risk should be accepted only when absolutely necessary and be exceeded only in extremely rare situations.

A7.3. Safe Distances for Friendly Troops (Conventional Weapons). When computing nonnuclear damage to enemy forces, the effectiveness index lethal area is used. Lethal area is sometimes incorrectly assumed to be a circle, and attempts are made to determine the resulting lethal radius. This cannot be done because the lethal area is not a physical area but instead an integrated probability over the area of effectiveness.

A7.3.1. Some agencies have been provided safe distances using damage criteria developed for deter-mining effectiveness against enemy soldiers, such as the 5- minute casualty criterion. These distances are much larger than the lethal radii discussed above but are still not considered suitable for the safety of friendly troops. For friendly troops, a much more stringent criterion for safety has been estab-lished. Effectiveness indices (EI) have been established to provide numerical values to establish the relationship between the target, weapon, and operational factors that influence the weapon's effective-ness. The effective target dimensions (length X width) cannot be used to determine a minimum safe distance from the impact point. Refer to the separate JMEM document Risk Estimates for Friendly Troops, 61A1- 3- 9. This document contains information pertaining to safe distances and provides esti-mates as to the percentage of casualties that could be expected to friendly troops by the delivery of 180

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munitions from friendly aircraft in close air support of those troops. Information is also provided per-taining to the minimum safe distance from bursting munitions that would ensure safety for personnel involved in training exercises, firepower demonstrations, testing and storage of munitions, etc.

A7.4. Safe Distances for Friendly Troops (Nuclear Weapons). Conventional weapons have relatively small effective radii against personnel, but their use in close support of tactical operations still involves some risk to friendly forces. Nuclear weapons increase this risk considerably because of their larger effective radii. Therefore, in the analysis of a potential nuclear target close to friendly troops or to a friendly civilian population, safety risk must be carefully evaluated. The following discussion of troop safety criteria is summarized in table A7.1.

Table A7.1. Troop Safety Criteria for Radius of Safety.

A7.4.1. When nuclear weapons are considered for employment against close- in targets, troop safety considerations may determine whether or not nuclear weapons will be used. If they are used, troop safety may influence the selection of yield, delivery means, location of the desired ground zero (DGZ), height of burst (HOB), and time of burst, as well as the ground commander's scheme of maneuver. Because of delivery errors and prevailing weather and terrain conditions, calculating the risk to friendly troops involves the use of probabilities and good judgment. It would be desirable to have a 100 percent assurance that no friendly casualties would result from our use of nuclear weapons, but as long as the possibility of delivery error exists, such an assurance is unlikely. As a rule, the com-mander will want a very high assurance (0. 99 probability) that his troops will not be exposed to weapon effects higher than those considered acceptable.



Unwarned, exposed Negligible Two- thirds of the thermal input (cal/ cm2) required to produce first degree burns on bare skin, or 5 rads nuclear radiation.

Moderate The thermal input (cal/ cm2)) required to produce first degree burns on bare skin, or 20 rads.

Emergency Two- thirds of the thermal input (cal/ cm2) required to produce sec-ond degree burns on bare skin, or 100 rads.

Warned, exposed Negligible Two- thirds of the thermal input (cal/ cm2) required to scorch sum-mer khaki uniforms, or 5 rads.

Moderate The thermal input (cal/ cm2) required to produce first degree burns under summer khaki uniforms, or 20 rads.

Warned, protected Negligible 5 rads inside medium tanks, or 3 psi over pressure. Moderate 20 rads inside medium tanks, or 5 psi overpressure. Emergency 100 rads inside medium tanks, or 10 psi overpressure. 181

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A7.4.2. When nuclear weapons are employed at a considerable distance from friendly troops, safety is a matter of concern from the following viewpoints:

A7. 4.2. 1. Areas of fallout contamination from surface bursts may preclude or interfere with friendly force use of, or passage through, these areas.

A7.4.2.2. A reasonable margin of safety must be provided for military and civilian populations of friendly and neutral countries in accordance with the area commander's weapons restraint policy.

A7.4.2.3. Temporary dazzle during daylight conditions, loss of night visual adaptation, or retinal burns may handicap friendly forces if they are not warned to protect their eyes at the time of deto-nation.

A7.4.3. In addition to degrees of risk, one of the following three conditions of personnel vulnerability can be expected at the time of burst: unwarned, exposed; warned, exposed; or warned, protected.

A7.4.3.1. Unwarned, exposed troops are assumed to be standing in the open at burst time but to have dropped to a prone position by the time the blast wave arrives. They are expected to have areas of bare skin exposed to direct thermal radiation, and some personnel may suffer temporary dazzle. For example, this condition can be expected in an offensive situation where the majority of the attacking infantry are in the open and cannot be warned of the burst.

A7.4.3.2. Warned, exposed troops are assumed to be prone on open ground, with all skin areas covered, and with overall thermal protection equal to that provided by a two- layer summer uni-form. For example, such a condition is expected to prevail when a nuclear weapon is detonated over a target at a prearranged time during an attack when troops are expecting the burst but do not have time to prepare foxholes.

A7.4.3.3. Warned, protected troops are assumed to be "buttoned up" in tanks or crouching in foxholes with improvised overhead thermal shielding. For example, such a condition is expected to prevail when nuclear weapons are used in support of an attack by our armored forces.

A7. 4. 4. The predicted ranges for thermal radiation and initial nuclear radiation are provided in the DIA manual, Physical Vulnerability Handbook-- Nuclear Weapons, AP- 550- 1- 2- INT.

A7.4.5. Troop safety distance calculations are usually based on a high assurance of not exceeding a certain criterion for safety. Aircraft and guided missile- delivered weapons require a horizontal buffer distance (d ) of 2 CEP for a very, very high safety assurance (0.99~ for a straight line troop disposi-tion; 2.3 CEP for a very high assurance (0.95) for either a half- circular or a circular troop disposition.

A7.4.6. A weapon set to burst at a fallout- safe height of burst has a 0.50 probability of being below the "selected" burst height on detonation. Therefore, to achieve an assurance of no fallout (of military significance), a vertical buffer distance must be added to the HOB. These distances can be obtained from figures in the Physical Vulnerability Handbook-- Nuclear Weapons, AP- 550- 1- 2- INT.

A7. 4.7. For a very high assurance that friendly troops will not be exposed to any weapons effects greater than those considered acceptable, add 2 CEP to the radius of safety (RS) to obtain the mini-mum safe distance (MSD), and add 3.5 Probable Error in Height (peh) to the fallout- safe height of burst (HOBfS).

A7.5. Macro Models for Computing Collateral Damage . Standard models are available in conven-tional and nuclear weaponeering manuals for use in determining expected collateral damage involving 182

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one or a few sorties and one or a few target elements. The planner can use these models as they stand, based on "average" estimates, or can apply conservative factors as outlined earlier in the sections on safe distances. For detailed target analysis collateral damage avoidance tables for each weapon system and yield can be obtained in FM 101- 31- 2/ AFP 200- 31, Volume II, Nuclear Weapons Employment Effects Data.

A7.5.1. These data can be aggregated into larger models providing insight into large scale situations involving thousands of targets and weapons. One such model is TANDEM (Tactical Nuclear Damage Evaluation Model), developed by the RAND Corporation. This program takes target data such as location and the probability of damage to targets and population centers, vulnerability numbers, inter-relation maps, weapon assignments (yield, height of burst, CEP, etc.) and other factors as inputs. TANDEM is analyzed, and outputs may indicate target damage, collateral damage, and bonus dam-age.

A7.5.2. A number of other programs are available or can be modified to compute large scale collat-eral damage. Nonnuclear weaponeering programs provided by the JMEM for programmable calcula-tors provide an "offset" capability to determine collateral damage. In these programs, the range offset and the deflection offset can be used to represent distances from aimpoint for facilities that may be subjected to collateral damage. These programs can be modified to provide numerous computations. 183



AIR FORCE PAMPHLET 14- 210 Intelligence