Cluster munitions are weapons that open in mid-air and disperse smaller submunitions— anywhere from a few dozen to hundreds—into an area. They can be delivered by aircraft or from ground systems such as artillery, rockets, and missiles.
Commonly, this is a cluster bomb that ejects explosive bomblets that are designed to kill personnel and destroy vehicles. Other cluster munitions are designed to destroy runways or electric power transmission lines, disperse chemical or biological weapons, or to scatter land mines. Some submunition-based weapons can disperse non-munitions, such as leaflets.
Cluster munitions are valued militarily because one munition can kill or destroy many targets within its impact area, and fewer weapons systems are needed to deliver fewer munitions to attack multiple targets. Cluster munitions also permit a smaller force to engage a larger adversary and are considered by some an “economy of force” weapon.
Cluster bombs were first used in World War II, and inclusive of their debut, cluster munitions have been used in at least 21 states by at least 13 different countries. The traditional cluster bomb is still in widespread use with thousands of the munitions being used since the invasion of Iraq began in 2003. They continue to be a favorite among those tasked with destruction of enemy air defenses (DEAD) along with battlefield interdiction against formations of vehicles and troops. Even some close air support missions, especially those where the exact target’s location is unknown, benefit heavily from cluster munitions.
On 21 February, the Egyptian military released a video on its official twitter account of what it claimed were improvised explosive devices planted by “terrorist elements”. However, Amnesty International has analysed this video and confirmed it shows an unexploded US made Mk 118 cluster munition, which could only have been dropped by the Egyptian air force.
Amnesty International arms experts’ analysis of the Mk 118 cluster submunition shown in the video reveals that it is untampered with and in good condition despite its age, with the serial number still clearly visible on its side. This suggests that the submunition has been deployed in recent operations
Because cluster bombs release many small bomblets over a wide area, they pose risks to civilians both during attacks and afterwards. Unexploded bomblets can kill or maim civilians and/or unintended targets long after a conflict has ended, and are costly to locate and remove. Cluster munitions have been highly criticized internationally for causing a significant number of civilian deaths, and efforts have been undertaken to ban and regulate their use.
Cluster munitions are prohibited for those nations that ratify the Convention on Cluster Munitions, adopted in Dublin, Ireland in May 2008. The Convention entered into force and became binding international law upon ratifying states on 1 August 2010, six months after being ratified by 30 states. As of 1 April 2018, a total of 120 states have joined the Convention, as 103 States parties and 17 Signatories.
However, United States’ recently ended its longstanding policy not to use unreliable cluster munitions and to destroy its stocks completely disregards the widely accepted international ban on these weapons, said Human Rights Watch. A Department of Defense policy memo signed on November 30, 2017, by Deputy Defense Secretary Patrick Shanahan indefinitely delays implementation of a ban on using unreliable types of cluster munitions that was due to take effect on January 1, 2019.
Submunitions lacking a self-destruct capability—referred to as “dumb” munitions—are of particular concern because they can remain a hazard for decades, thereby increasing the potential for civilian casualties. Some nations are developing “smart” or sensor-fuzed weapons with greater reliability and a variety of self-destruct mechanisms intended to address the residual hazard of submunitions.
For some nations, replacing “dumb” and high-failure rate cluster munitions may not be an option—China, Russia, and the Republic of Korea maintain that they cannot afford to replace all current submunitions with “smart” submunitions.
A basic cluster bomb consists of a hollow shell and then two to more than 2,000 submunitions or bomblets contained within it. Some types are dispensers that are designed to be retained by the aircraft after releasing their munitions. The submunitions themselves may be fitted with small parachute retarders or streamers to slow their descent (allowing the aircraft to escape the blast area in low-altitude attacks).
Two technical characteristics of submunitions—failure rate and lack of a self-destruct capability—have received a great deal of attention. There appear to be significant discrepancies among failure rate estimates. Some manufacturers claim a submunition failure rate of 2% to 5%, whereas mine clearance specialists have frequently reported failure rates of 10% to 30%. %.
A number of factors influence submunition reliability. These include delivery technique, age of the submunition, air temperature, landing in soft or muddy ground, getting caught in trees and vegetation, and submunitions being damaged after dispersal, or landing in such a manner that their impact fuzes fail to initiate.
The 2008 policy required that the US not use cluster munitions that result in more than 1 percent unexploded ordnance (UXO) from 2019 onward. The new policy allows US military commanders to approve use of existing cluster munitions “until sufficient quantities” of “enhanced and more reliable” versions are developed and fielded. The new policy also facilitates US acquisition of cluster munitions from foreign sources to replenish stocks.
Development of Newer safer accurate Cluster Bombs
The Pentagon is on one hand trying to improve the safety, accuracy and reliability of cluster munitions as well as finding new ways to achieve the same affects smartly. U.S. mainly uses guided cluster bombs in the form of the Wind Corrected Munitions Dispenser (WCMD). This is basically a guided tail-kit attached to existing cluster bombs that uses an internal inertial guidance system to fly towards its target area.
It does not make these cluster bombs precision-guided munitions but increases their accuracy by compensating for wind encountered during the canisters’ fall. The WCMD can reduce humanitarian harm by making it less likely civilians will be hit by a cluster bomb that goes astray (a significant problem in Afghanistan where the older CBU-87 was used widely). It does not make cluster bombs precision munitions that are safe to use in populated areas, nor does it eliminate the duds that endanger civilians after strikes.
Many cluster munitions rely on simple mechanical fuzes that arm the submunition based on its rate of spin and explode on impact or after a time delay. A newer generation of sensor-fuzed submunitions is being introduced by a number of nations to improve the munitions’ and submunitions’ accuracy and to reduce the large number of residual unexploded submunitions. These sensor-fuzed submunitions are designed to sense and destroy vehicles without creating an extensive hazard area of unexploded submunitions.
The SFW has the same canister as the more common CBU-87 or -103, but it contains ten BLU-108 submunitions instead of 202 BLU-97s. The SFW’s submunitions each contain four hockey puck-sized, explosive “skeets” with infrared sensors that guide them to armored targets and self-destruct mechanisms to reduce the number of duds. They have the potential to reduce the civilian cost of cluster munitions because both their canisters and skeets are guided and because their dud rate should be lower. They also target vehicles and do not create an indiscriminate antipersonnel effect.
Another idea is to replace cluster bomb’s grenade-like sub munitions with non-explosive kinetic projectiles. Thus high-speed hot cast iron shrapnel are used to tear apart the enemy and their armor and once the bomb is detonated, its cast iron, pieces fall to the earth and stay there harmlessly rather than like time bombs waiting to be blasted. The degradation of wide area effect destruction effect of a dispenser concept like the popular CBU-87 Combined Effects Munition currently in service, can be partly compensated with improvements in bomb guidance.