One of the ways to protect armored vehicles from cumulative ammunition is mesh screens of a special configuration. Such attachments are capable of destroying an approaching grenade or rocket, eliminating its detonation, or provoking a warhead to trigger at an suboptimal distance from the armor. Mesh screens are traditionally used to protect combat vehicles, but can also be installed around stationary structures. For example, the Russian defense industry offers the so-called. the Loza engineering protection system.
The experience of recent local conflicts shows that stationary objects of troops, such as checkpoints, barracks, warehouses, etc., can be fired upon using any weapon. Depending on their capabilities, the enemy can use small arms, light artillery or anti-tank systems. The latter, despite their different purpose, are quite capable of inflicting significant damage on structures and buildings. Thus, buildings and structures may require special protective equipment.
The Loza engineering protection system deployed in addition to the brick-lattice fence
In the late nineties, the Scientific and Production Association of Special Materials (St. Petersburg) considered the current threats and needs of the troops, and also studied possible approaches to the protection of facilities. Taking into account the results of such studies, the company has developed a new version of anti-cumulative protection of buildings, based on well-known principles. The promising development was named the Loza engineering protection system.
The Vine project was based on the well-known and proven principle of protecting an object with a mesh screen. Once in the path of a cumulative munition, such an obstacle provokes its detonation or violates the integrity of the charge - in both cases, the impact on the protected object is sharply reduced. At the same time, NPO SM specialists took into account some of the features of the cumulative warheads and formed an updated look of the screen, capable of showing higher characteristics.
The main element of the Loza protection system is a rectangular screen-module. It is a frame made of metal profiles reinforced with triangular gussets at the corners. Each such module has a width of 2 m and a height of 2.5 m, which makes it possible to cover any standard fence or fencing with screens. The frames are equipped with special devices for quick assembly and connection of several modules into a large structure of the required configuration.
A metal mesh is stretched on the frame with an interlacing of the Rabitz network type. The size and shape of the cells of such a grid is determined in accordance with the parameters of the most common cumulative ammunition used with the popular anti-tank grenade launchers. The relatively small sizes of the rhombic cells guarantee the contact of the flying grenade with several sections of the wire at once. Sufficient strength of the wire and the network woven from it, in turn, allows you to destroy the warhead of the ammunition or provoke its premature operation.
Since one network cannot always provide the required protection against any conventional ammunition, the designers of the NPO of special materials made the Loza system two-layer. It contains two rows of mesh barriers, located in a special way. The outer row of screen modules forms a straight line or contour of the required shape, while the inner row is a broken line along its entire length.
Installation of the Loza engineering protection system is not the most difficult task. It is proposed to dig in or drive in support pillars of a given height along the perimeter of the protected object. The distance between the individual posts is equal to 2 meters - across the width of the module frame. Separate screens are installed between the posts in one line, forming the first defense perimeter. In the event of an attack, it is he who will have to absorb the kinetic energy of the ammunition and take over part of the shock wave and cumulative jet when it is detonated.
"Vine" at another object
The second row of protection is installed on the same support pillars using the proposed mountings. It is proposed to mount two other modules behind each screen of the first row at a large angle to it. Three modules form a triangular structure with two lines of protection. Two vertices of such a triangle are located at the pillars, and the third is located on the side of the protected object. The joint use of two rows of screens with their installation at an angle to each other is said to significantly increase the combat characteristics of the entire complex.
According to the manufacturing organization, the Loza protection system can be equipped with additional means of preventing access. Brackets with fasteners tilted 45 ° outward can be attached to the support posts of the system. They should be hung with barbed wire, which will not allow the intruder to get over the screens.
The "Loza" system shows the best results during installation in compliance with all the developer's recommendations. It is recommended to install it at a distance of about 10-20 m from the protected object, which eliminates all the main risks during shelling. According to official data, in the optimal configuration, the screens remove the high-explosive effect on the building, and also reduce the risks associated with fragments and a cumulative jet to a safe level.
It is argued that the engineering protection system can be used to improve the safety of various objects of low height. At the same time, it serves as a special addition to other standard protective equipment and structures. For example, there is a brick or concrete fence around a warehouse, headquarters or other facility, which, by definition, will not withstand shelling from anti-tank weapons. At a given distance from such a fence, a "Vine" can be deployed, as a result of which the object will receive comprehensive protection from intruders and various weapons.
A characteristic feature of the Vine screens is their purpose. This protection system is intended only for equipping stationary objects. A modification for installation on armored vehicles was not developed. In this respect, the domestic screen differs from some foreign developments, the authors of which tried to create a universal protection for installation on stationary and mobile objects.
Screen after being hit by an RPG-7 grenade
From the point of view of the basic principles of work "Loza" does not differ from other similar systems. Moreover, its design uses such principles in a rather interesting way. An approaching grenade must hit the outer mesh screen, which leads to known consequences. The grenade is either destroyed mechanically or detonated at an excessive distance from the attacked target.
In the latter case, the explosion and the cumulative jet break through the network of the first screen. However, further on their way, at some distance from the first screen, the second one appears. A significant part of the remaining energy of the jet is spent on making a hole in a new obstacle, after which the remaining jet is dispersed in the air. Even if part of the hot gases or molten metal reaches the protected object, they will not be able to damage it. At the same time, a pair of nets will retain a significant part of the fragments.
In the best case, hitting the net will destroy the grenade. In advertising materials from NGOs, special materials were shown the result of such a development of events. Having hit the first screen, the PG-7V grenade of the RPG-7 rocket launcher split into many separate parts, which, moreover, were seriously deformed. Instead of a single grenade launcher shot, a curved fairing and grenade body, a dented engine shank, and torn off and twisted fins were demonstrated. The torn screen mesh, however, did not look better after the impact of the grenade.
According to NPO SM, the mesh screens of the Loza system are uniquely resistant to explosions of cumulative ammunition. When a PG-7V grenade is hit, the mesh is destroyed on an area of no more than 5 square dm - the screen rupture has a diameter of 20-25 cm. Thus, one grenade hit disables about 1% of the entire area of the screen module. The rest of the product area is likely to maintain the required characteristics and can continue to perform its tasks.
It should be noted that screens made of metal mesh, especially supplemented with brackets with barbed wire, can be protection not only against anti-tank weapons. They are also capable, at a minimum, of apprehending the intruder and preventing him from quickly entering the restricted area. The presence of a "thorn" makes it difficult to overcome the obstacle through the top in the most serious way, and it takes a lot of time to cut the mesh. In addition, the second row of screens becomes an additional obstacle. We can say that the "Loza" in combination with any other fence creates a real multipurpose echeloned defense.
According to the available information, the Loza engineering protection system, developed and presented in the late nineties, quickly found its buyers and went into series. Various military and civilian structures appreciated the original proposal of domestic engineers, as a result of which the NGO of special materials was able to master the production of a new type of product.
Fragments of a rocket-propelled grenade after a meeting with the "Loza"
According to various sources, the Vine screens have been deployed at multiple sites across the country. At the same time, particular attention is drawn to the well-known facts of the use of engineering protection systems on the territory of the Chechen Republic. In the recent past, military units and civilian objects of this subject of the federation, for obvious reasons, were exposed to special risks. The available means of protection were not always able to cope with the current threats, and therefore the Loza-type systems were not superfluous.
Objects in other regions, which were not characterized by the problems of Chechnya, could use the engineering protection system as an addition to the existing means of protection. In this case, it could be used, first of all, as a second fence around the object. The anti-cumulative function turned out to be not the most necessary, but also not a superfluous addition.
It is curious that the operators were not always able to comply with all the manufacturer's recommendations and deploy the engineering protection system in the optimal configuration. According to NPO SM calculations, the Loza shows the best results when the screens are installed at a distance of at least 10 m from the protected object. In this case, an incompletely destroyed cumulative jet or fragments manage to lose all their energy in time and cease to threaten their goal. Decreasing the distance to the screen can increase the risks.
Nevertheless, it was not always possible to install the screens at a sufficient distance. As a result, the structure of mesh modules was mounted, including in the immediate vicinity of the object's own fence. To what extent this reduced the effectiveness of the barrage - is unknown. However, it can be assumed that with a pair of mesh screens, the concrete fence protected people and material better than without them.
Loza engineering protection systems are still being produced and operated. Apparently, since the beginning of the 2000s, modular anti-cumulative screens supplied by NGOs of special materials have been regularly deployed at new and new facilities in different parts of the country. There is no information on the number of systems produced, but it can be assumed that the number of serial kits has long gone into the hundreds. "Loza" remains in the product catalog of the developer company, and to this day it is offered to potential customers.
Mesh screens of several models have already entered service with a number of armies and, as some events show, they cope with their task, dramatically reducing the negative impact of ammunition on the protected equipment. In some cases, we are talking about the installation of unified grids on both combat vehicles and stationary objects. The domestic project of the Loza engineering protection system also provides protection for various buildings, but does not provide for the installation of screens on machines. However, the “narrow specialization” of this system allows you to get rid of the potential problems associated with universality, and to obtain the desired potential for protection. Numerous orders for the supply of modules for installation at certain facilities have long ago become a clear confirmation of the high characteristics of the Loza.
