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1. Background

a. Saturation of unexploded submunitions has become a characteristic of the modern battlefield. The potential for fratricide from UXO is increasing. It applies throughout the battlefield (e.g., special operations forces [SOF]) in deep operations, maneuver forces in close operations, and the movement of forces and support operations within the rear area). Commanders must consider risks to soldiers, sailors, airmen, and marines from UXO and integrate UXO into their antifratricide planning. This tactics, techniques, and procedures (TTP) publication provides the methodologies for planning, implementing, and executing procedures to protect forces from unexploded submunitions.

b. United States (US) or allied casualties produced by friendly unexploded submunitions may be classified as fratricide. Locations where unexploded submunitions have been or may be encountered require accurate tracking to assist commanders in reducing the potential for fratricide. Currently no system exists to accurately track unexploded submunitions to facilitate surface movement and maneuver. This publication addresses the impact of UXO on operations at the operational level and below and describes TTP to assist leaders at all levels in reducing the hazards of UXO. This chapter establishes the scope of the UXO problem and focuses on the potential effects of UXO on all surface forces throughout the battlefield (including SOF).

c. Joint Publication 1-02 defines unexploded explosive ordnance as "explosive ordnance which has been primed, fused, or otherwise prepared for action, and which has been fired, dropped, launched, projected, or placed in such a manner as to constitute a hazard to operations, installations, personnel or material and remains unexploded either by malfunction or design or for any other cause." Although ground forces are concerned with all unexploded ordnance, the greatest potential for fratricide comes from unexploded submunitions. For this reason, the scope of this publication focuses on unexploded submunition hazards. However, if the situation warrants, the tracking process described in later chapters can be used to track all potential UXO hazards. While US weapon system examples are used in this publication, most foreign militaries possess similar systems. Appendices D-E list types and quantities of US and foreign submunitions ordnance. Family of scatterable mines (FASCAM) operations are beyond the scope of this publication.

2. Hazards

Both surface and air-delivered ordnance produce unexploded submunitions. Several factors, such as the delivery technique, age of submunition, ambient air temperature, and type of impact medium, influence the reliability of submunitions. The actual hazard area produced depends on the type of ordnance and the density of the UXO.

a. Surface Delivery Systems. The Army and Marine Corps employ a variety of rockets, missiles, and cannon artillery. Each system is capable of delivering improved conventional munitions (ICMs) that contain submunitions. A typical Army heavy division is equipped with 9 Multiple Launched Rocket Systems (MLRSs) and 72 tubes of cannon artillery. Cannon artillery basic load is generally 60-70 percent dual-purpose, improved conventional munition (DPICM), while 100 percent of the MLRS and Army Tactical Missile System (ATACMS) basic loads are submunitions. Thus every MLRS and ATACMS fire mission and over half of the fire missions executed by cannon artillery produces UXO hazard areas. Additionally, the Tomahawk land attack missile. Version D (TLAM-D), is the submunition version of the Tomahawk missile and has the potential to produce similar UXO hazard areas.

(1) MLRS Unexploded Submunition Hazards. MLRS submunition function reliability requirement is no less than 95 percent. With a 95 percent submunition function reliability, 1 MLRS rocket (with 644 submunitions) could produce up to 38 unexploded submunitions. A typical fire mission of 36 MLRS rockets could produce an average of 1368 unexploded submunitions. The numbers of submunitions that fail to properly function and the submunitions' dispersion determine the actual density of the hazard area.

(2) Cannon Artillery. Cannon artillery employs the same submunitions as MLRS. The difference is the number of submunitions per round. A battalion-2 (24 cannon firing 2 rounds each for a total of 48 rounds) with a 95 percent submunition reliability produces, on average, 212 unexploded submunitions.

b. Air Delivery Systems. There is no set air delivery mission profile. Most airframes are capable of delivering a variety of submunitions. The UXO hazard area depends on the submunition, mission profile, target type, and number of sorties. Air Force and naval air power employ cluster bomb units (CBUs) containing submunitions that produce UXO hazard areas similar to MLRS/cannon artillery submunitions. Air delivered canisters contain varying amounts of CBUs (see Appendix C). One CBU-58 or three CBU87/CBU-52 contain approximately the same number of submunitions as one MLRS rocket. AB-52 dropping a full load of 45 CBUs (each CBU-58/CBU-71 contains 650 submunitions) may produce an UXO hazard area that is significantly more dense than an MLRS UXO hazard area. A typical F-16 flying close air support (CAS) against a point target may drop two CBUs per aircraft per run, thus producing a very low-density UXO hazard area. Again, the type and number of canisters dropped will determine the density of the UXO hazard area.

3. UXO Impact on Forces

UXO affects operational and tactical planning and execution of operations. Types of munitions employed, self-destruct times, and submunition densities must be evaluated regarding the forces that deal with them. Variables affecting the degree of risk include, but not limited to, the types of submunitions employed; protection available to US personnel (e.g., armored vehicles versus dismounted infantry); mission of the affected force; and terrain and climatic conditions within affected operational areas. Planners must consider the risks of UXO for any mission, regardless of the unit.

a. Operational Impacts of UXO. Planners need to consider the types of submunitions, where they are/were employed, and their potential impact on future operations. Without careful planning, maintaining the operational tempo will be difficult in an UXO environment. Planners must allocate additional time for the operation if a deliberate breach or bypass of UXO hazard areas is required. Additionally, planners should consider--

(1) Tracking and reporting requirements.

(2) Task organization/additional force requirements (e.g., requirement for additional engineer or explosive ordnance disposal assets).

(3) Reconnaissance requirements.

(4) Breaching requirements.

(5) Maneuver requirements (restrictions on avenues/axis of attack).

(6) UXO hazard area marking requirements.

(7) Civil-military operations requirements (impact on civilian population).

b. Tactical Impacts of UXO. UXO inhibits maneuver by potentially restricting use of terrain, increasing reconnaissance requirements, and reducing momentum (speed of maneuver and rates of march). UXO also inhibits night movement, increases risk to combat support (CS)/combat service support (CSS) elements, ties up engineers or other forces clearing/marking lanes, and reduces available firepower because of increased loss of personnel and equipment.

c. Armored/Mechanized Forces. Armored and mechanized forces consist of tracked and wheeled vehicles. Commanders must consider the force as a whole when planning operations. Chance of significant damage to armored, light armored vehicles (LAV), and other wheeled armored vehicles is relatively low. The primary damage occurs where the track or wheel contacts the submunition. Depending on the type of submunition, a mobility kill could occur. There is little possibility of casualties from crossing UXO hazard areas as long as the crews stay mounted. Armored and mechanized commanders must also consider the increased risk to their organic wheeled vehicles and dismounted forces when operating in UXO environments. High mobility multipurpose wheeled vehicles (HMMWVs) and other "soft skin" vehicles accompanying and supporting combat elements are at greater risk. Anytime crews must dismount their vehicles, they are increasing their risk.

d. Dismounted Forces. Dismounted forces face the greatest danger of death or injury from UXO. Unexploded ordnance is a significant obstacle to dismounted forces. Dismounted forces require detailed knowledge of the types and locations of submunitions employed.

e. Wheeled Vehicles. Personnel being transported by wheeled vehicles face nearly the same risk to UXO as dismounted forces. The protection afforded by wheeled vehicles is negligible. Wheeled vehicles are vulnerable to damage from UXO. Chance of catastrophic destruction is slight; however, contact with UXO normally results in disabled wheeled vehicles. Maintenance evacuation may be required depending on the type vehicle and where the damage occurred.

f. Air Assault and Aviation Forces. Air assault and aviation forces are also at risk to UXO. Aircraft in defilade, flying nap-of-the-earth, or in ground effect are vulnerable to submunitions. US Rockeye and Soviet PTAB submunitions incorporate piezoelectric crystals that can react to aircraft in ground effect. Antipersonnel and antimateriel (APAM) and M42/M46 grenades are also sensitive enough to function as a result of rotor wash. It is imperative aviation units know the location of employed submunitions and conduct thorough reconnaissance of the area before conducting operations or occupying assembly areas and forward arming refueling points (FARPs).

g. Amphibious Landing Craft. UXO has the potential to significantly damage certain types of landing craft and in some cases result in casualties of embarked personnel.

4. UXO Hazard Quantified

This section compares the UXO hazard area encounter probability with a minefield encounter probability. The probability of encounter is roughly equal for a minefield and an UXO hazard area of equal density (Figures I-1 and I-2). The minefield is more lethal as every mine is designed to detonate by some action, where the unexploded submunition results from a malfunction and may or may not detonate upon contact. They may also detonate without contact because of climatic changes, corrosion, etc., Figures I-3 and I-4 illustrate the expected damage/casualties for various densities of UXO hazard areas. Comparing Figure I-1 with Figures I-3 and I-4 gives a potential impact on the mission.

a. Figure I-2 illustrates the vehicle probability of encountering a single unexploded submunition versus the hazard area UXO density. The UXO probability of encounter is very similar to that of a minefield; however, the lethality of the UXO hazard area is lower.

b. Figures I-3 and I-4 show the expected damage and casualty rates for various densities of DPICM and bomb live unit (BLU) 97 UXO hazard areas. These charts represent one vehicle/person passing through a one-half kilometer deep UXO hazard area. The probabilities shown are per vehicle/person. To calculate the expected number of casualties, multiply the number of vehicles/persons (or passage lanes) by the probability of encounter. The X-axis (mines per meter front) is a linear density expression of the average number of mines within a 1 meter path through the minefield's depth. The vehicle and tank probabilities differ because of the differences in width and the area in contact with the ground (track versus tire width). Each chart is based on Army Materiel Systems Analysis Activity Studies that show 40 percent of the duds on the ground are hazardous and for each encounter with an unexploded submunition there is a 13 percent probability of detonation. The probability lines within the graphs reflect 13 percent probability of detonation per encounter. Thus, even though an unexploded submunition is run over, kicked, stepped on, or otherwise disturbed, and did not detonate, it is not safe. Handling the unexploded submunition may eventually result in arming and subsequent detonation. Troops moving through a hazard area must be fully familiar with the hazards of the submunitions they will encounter.

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