Article from Schweizer Soldat. LASSO: simple but ingenious

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1 Article from Schweizer Soldat LASSO: simple but ingenious The challenge facing all armed forces today is how to provide their armoured personnel carriers, reconnaissance vehicles and infantry fighting vehicles with better protection against mines and ballistic attack. One design solution offering a high degree of protection has been developed in Thun, Switzerland, by RUAG. The conflicts in Iraq, Afghanistan and Africa illustrate very clearly that vehicles developed during the Cold War era no longer provide their crews with adequate protection in asymmetrical combat environments. Generally speaking, they have adequate armour protection against shrapnel, fragments and medium to heavy machine gun fire. The vehicles' basic protection frequently needs to be reinforced with add-on armour and sometimes with reactive appliqué armour panels as well. These provide limited protection against the anti-tank weapons used in street battles in built-up areas. However, these additional protective measures also increase the weight of the vehicles, making them less manoeuvrable and increasing fuel consumption without protecting them against booby traps. Lessons learned by the Americans The inadequate protection on their vehicles forced the Americans to act. Deaths and injuries to their soldiers caused by a wide variety of explosive charges, known as Improvised Explosive Devices (IEDs), were too great not to look for better means of protection. The first step was the Mine Resistant Ambush Protected or MRAP vehicle. The MRAP programme includes three different vehicle categories: support vehicles, transport column escort protection vehicles, and vehicles for mine clearance and IED removal. All three categories provide protection against small arms fire, artillery shell fragments and mines containing up to 10 kilograms of explosive. Everyone is affected All countries with troops deployed in conflict areas are faced with the task of protecting their soldiers. This includes traditional methods such as reinforcing vehicle armour, jamming radio-controlled roadside bombs and laying smokescreens. However, protected vehicles are not yet available everywhere. One general described the dilemma like this: "If we increase our armour protection, then the Taliban simply bury bigger mines or they pack more explosive into their booby traps". A solution from Thun RUAG Land Systems, based in Thun in Switzerland s Bernese Oberland, is marketing what appears at first sight to be a simple wire mesh screen under the name LASSO (Light Armour System against Shaped Ordnance). LASSO is the culmination of years of experience with munitions and their effects. The screen provides up to 60 percent protection against ballistic attack by the RPG-7 anti-tank grenade launcher, commonly available worldwide. RPG-7 rounds operate on the anti-tank shaped charge principle and are capable of penetrating between 320 and 450 mm of armour steel at a range of 100 to

2 a maximum of 200 metres. The weapon is easy to operate. It does not have a high hit probability and relies on the skill of the firer. Currently, an RPG-7 can be easily bought on the black market for less than 100 dollars. It is used in large numbers by regular and irregular formations in so-called asymmetrical conflicts in the Middle East, Asia and Africa. It is used not just against armoured vehicles but also against fortified weapon positions. Armoured vehicles and infantry fighting vehicles are particularly at risk in close terrain. Author: Lieutenant colonel Peter Jenni, Muri /Berne, is deputy editor-in-chief of the journal SCHWEIZER SOLDAT

3 -3- Decades of expertise and experience Research and development work into large-calibre munitions has been conducted for more than 30 years in Thun. Until 18 years ago, the work was carried out at the Konstruktionswerkstätte Thun (KW), founded in 1847; in the 1990s, this became the Schweizerische Unternehmung für Munition AG (Swiss munitions company). Since RUAG was formed ten years ago, the work has been continued by the Warhead Division of the RUAG Land Systems business unit. Only recently, RUAG Land Systems together with GEKE of Germany established a new company, which has resulted in a significant increase in the capacity for research, development and testing of protection products. According to Anthony Rossi, Systems Manager Protection & AIF at RUAG Land Systems, the development, manufacture and marketing of the LASSO wire mesh screen system is a central element of the protection system product sector. The idea of developing LASSO emerged some three years ago after indications from the sales and marketing front, from international conferences, and from armed forces that have formations deployed in conflict regions. The design engineers idea was to discover the lightest possible protection system. Existing auxiliary systems generally weigh between 1.5 and 3 tonnes. Compared to their nominal power-to-weight ratio, this makes the vehicles too heavy, limits their mobility and restricts the crew's field of vision. Thanks to their knowledge of how RPG-7 rounds are designed and how they function, the experts in Thun, together with partner company Geobrugg AG in Romanshorn Switzerland, came up with the idea of a steel mesh design. The aim is to weaken the effect of the round before it impacts the armour to the extent that it no longer poses a threat to the vehicle and its crew. In other words, a solution had to be found to prevent the round, weighing between 1.8 and 2.1 kg, with a diameter of between 58 and 105 mm and travelling at a velocity of 300 m/s, from fully exploiting the effect of the hollow charge jet. Numerous trials using different mesh geometries, varyingly tensioned mesh structures, different fixing methods, computer simulations and tests conducted both in the firing tunnel and in the open have led to the fully-marketable product.

4 -4- The LASSO mesh screen is constructed from 4 mm thick, high-tensile, deformation-resistant special steel. The mesh gauge is smaller than the RPG-7 calibre. The trials were photographed and filmed using high-speed cameras and measured by a velocity radar. Tests to ascertain resistance to jolting and vibration were also conducted. Unique advantages In a short space of time, the experts in Thun have successfully brought to market a means of protection that has three significant advantages over its competitors: LASSO weighs a good 50% less than any competitor's product. Compared with systems that employ steel profiles arranged horizontally, the steel grille s geometry offers greater protection. This is because an incoming round rarely impacts at an angle of 0 degrees. At a more acute impact angle, the horizontal steel profile design runs a greater risk of the grenade and its triggering mechanism striking the vehicle's protection and releasing the hot armour-piercing copper jet. It is precisely this risk that needs to be avoided. The LASSO system has hardly any adverse effect on the crew's field of vision, especially that of the driver. If individual sections of mesh are torn by one of more impacts, the component will need to be replaced in the rear support area. The crew can restore an M113's all-round protection in a few hours, without the need for special tools. Remember, too, that LASSO is also ideal for providing static, fortified positions with protection against anti-tank weapons.

5 -5- Initial market success Just six months after being brought to market in September 2008, LASSO has achieved a major success over competitor products. The Danish armed forces will fit LASSO to their M113 armoured personnel carriers that are deployed in Afghanistan as part of the UN peacekeeping mission. The Danes took this decision because the Thun solution is well-proven, provides excellent protection, weighs little and does not obscure the crew's field of vision. Demonstrated to an international audience On 21 and 22 October 2008, a demonstration was held before a group of international experts on the Ochsenboden firing range in Canton Schwyz. Representatives from 19 countries were present. Judging by the comments made, the visitors were impressed with the capability of the system developed in Thun. Senior managers at RUAG Land Systems are convinced that their product will play an important role on the international market.