By Stephen Turner, Counter Threat Solutions Ltd
The IED has become the insurgent’s weapon of choice in Afghanistan and now trending globally responsible for approximately 67 per cent of coalition casualties1. The Taliban Senior Leadership (TBSL) has recognised the benefits of employing the IED and has stated:
“One of the top three priorities for the spring offensive is to increase indirect attacks against Coalition Forces using IEDs2.”
Whilst the actual number of IEDs encountered within the Allied area of operations has now stabilised, there will be a continuing requirement for EOD force elements to be provided with effective weapons for countering IEDs for as long as Allied Forces are deployed in Afghanistan and other areas of hostility. The level of technical sophistication of IEDs employed by insurgents in Afghanistan remains relatively low, but the insurgent has demonstrated consistently the ability to employ tactical innovation and evolutionary development to continue to maintain and increase the effectiveness of the IEDs that he employs.
The majority of IEDs that are encountered currently in Afghanistan are either victim operated or command initiated, with approximately 80 per cent of devices being of the victim operated (VO) improvised pressure plate (PP) variety. The insurgents have responded to the coalition use of metal detectors to locate IEDs and the overwhelming majority of VO PP IEDs are now of low metal content and are difficult to detect. Over time, the nature and type of the IED main charge employed by the insurgent has also changed. Most IED main charges are now contained within plastic containers in order to minimise the potential for devices to be detected through the use of metal detectors. The average size of a main charge has also increased. Devices solely intended to attack dismounted troops have a main charge of approximately 3-5 kg of home-made explosive (HME). Devices intended to attack vehicles often have main charges containing in excess of 20 kg of HME.
A recent trend has seen the increased use of secondary and tertiary devices and approximately 30 per cent of all IED incidents now involve complex scenarios where either multiple IEDs are employed or multiple means of initiation, including booby traps, employed on the same IED. To further complicate the task of the IED searcher and EOD operator, most IEDs are either buried in the ground or in compound walls thus presenting very little of an obvious target for the EOD operator to attack.
The Ground Ordnance Land Disruptor (GOLD) has been designed to provide a safe and effective method for dealing with one of the most hazardous types of IED, the buried victim operated device. GOLD is a user filled, explosively driven system that renders safe buried IEDs through a combination of disruption, component separation and expulsion from the ground. The technology readiness level (TRL) of GOLD is 9. GOLD is now in low rate initial production and has been sold to a number of allied nation specialist units. GOLD is extremely effective at both disrupting and destroying buried IEDs and provides a reliable method of dealing simply with the type of IEDs encountered most frequently in Afghanistan. GOLD achieved a success rate of 83 per cent when tested against buried IEDs in hard desert ground in Jordan and has now been procured by allied NATO countries.
GOLD CHARACTERISTICS AND METHOD OF OPERATION
GOLD consists of three basic assemblies: a propulsion assembly, a warhead assembly, and a ground penetrator. The basic system components are shown in Figures 1 and 2. The system has an operational weight of 7.5 kg and is completely inert until filled with explosive prior to operational use.
The propulsion system consists of a single assembly that holds a series of explosively driven plates. The propulsion system is slotted to take the warhead assembly and this joint is a simple push fit. The propulsion system is driven by a conventional military plastic explosive such as C4 or PE4. Approx-imately 150 g of explosive, arranged hemispherically over a driving plate, is sufficient to drive the warhead assembly up to 60 cm into very hard ground. The explosive in the propulsion system is initiated by a conventional detonator or blasting cap. The propulsion system uses a series of interleaved metal and rubber plates to reduce peak stresses on the disrupter and to improve its penetrative performance in very hard ground.
The warhead assembly is a cylindrical hollow metal tube that has push fit joints for attachment of the ground penetrator and propulsion assembly. The lower section of the warhead assembly is configured with longitudinal grooves that create linear explosively formed projectiles which provide this device with its principal disruptive means of operation. The warhead is a user-filled item and is only fitted with explosive and the means of initiation immediately prior to use. The quantity of explosive employed can be varied by the user depending on the threat and required effect. To improve the speed of loading and the integrity of filling, the delay detonator and main explosive charge are placed into a charge holder. The warhead tube has a number of longitudinal grooves that facilitate the creation of coherent, linear explosively formed projectiles that disrupt and separate IED components in the ground. The warhead explosive charge is initiated by a non-electric delay detonator which is in turn initiated by a shock tube that is threaded through the propulsion explosive charge.
Method of Operation
On initiation of the propulsion explosive charge, force is exerted through the propulsion system and the GOLD warhead is driven into the ground. Detonation of the propulsion charge also initiates the pyrotechnic delay in the warhead detonator. After a pre-determined delay, the delay detonator functions and detonates the main warhead explosive charge. The high pressures thus generated causes the warhead assembly to expand along its radial axis and the presence of grooves on the outer surface of the warhead assembly results in the creation of linear explosively formed projectiles as a result of the Misznay-Schardin effect. These high velocity projectiles move out along a radial axis from the warhead assembly and disrupt and separate any IED components in their path. The fragments are eventually stopped due to the resistance of the ground. The blast wave from the warhead initially follows and then overtakes the warhead fragments and causes further separation of the IED components. The detonation of the warhead explosive charge also produces a significant volume of gaseous detonation products.
GOLD has entered low rate initial production (LRIP) and a number of systems have been built to support qualification testing and demonstrations.
GOLD has been tested during development against a variety of realistic IED targets including the following:
a. IED main charges with a mass up to 35kg in palm oil type plastic containers.
b. IED main charges based on ERW/ UXO (typically a 105mm smoke carrier shell filled with ballast) with a mass of approximately 13kg.
c. Low metal content pressure plates.
d. Power source configurations of various types.
e. Secondary means of IED initiation such as radio control switches or anti-lift switches attached to IED main charges.
f. Daisy-chained IEDs with multiple warheads.
1 LF EOD & Search branch statistics.
2 HQ ISAF C-IED Advisory, Plans and Policy Team, stated at the 5th UK C-IED Conference.
ABOUT THE AUTHOR
Stephen Turner is the founding director of Counter Threat Solutions and brings 25 years of experience in defence and security operations with government agencies. He started with an early engineering career which developed into specialist units and organisations with focus on actionable dynamic intelligence developing the fusion of Attack the Network and C-IED methodology.
This article first appeared in the Counter-IED Report, Spring/Summer 2014 edition, published by Delta Business Media.