Mine-explosive obstacles are the most important element of defense, and their organization requires the use of special equipment. The placement of mines on the ground can be carried out in various models using different methods of work. An interesting way of installing mines was implemented in the American project of the M128 GEMSS mining system. This product could, in the shortest possible time, create large fields with the use of anti-tank or anti-personnel mines of several types.
A new principle
By the early seventies of the last century, the US Army had several systems for quickly mining the terrain with several types of explosive devices. Used special artillery shells, cluster bombs and ground devices. These products, in general, met the current requirements, but did not always suit the troops. In this regard, in the early seventies, the development of a new land-based mining system with the required characteristics and capabilities began.
M548 transporter with M128 installation. Photo Tankograd.com
The development of a new model was carried out with the participation of specialists from the engineering troops and was completed in the middle of the decade. In 1975, the new model was adopted under the designation M128 GEMSS (Ground Emplaced Mine Scattering System). Soon, the army received the required number of new systems and deployed them in areas of alleged conflict. New equipment was primarily sent to Europe.
When developing a promising mining system, an unusual principle of scattering mines over the territory was used. Instead of pyrotechnics, a centrifugal-type mechanism with an electric drive should have been used. The principle of operation of such an installation was to disperse a mine using a rotor, followed by sending it towards the field.
The GEMSS system was not particularly complex in design. It was proposed to build a towed system based on a wheeled trailer, carrying several basic devices. Such a product could be towed by any available equipment and mine the terrain on the go. At the same time, it was possible to change the main parameters of the barrier. In particular, the density of mining along the front directly depended on the speed of the tractor.
Design
The M128 product was built on the basis of the standard M794 two-axle trailer, widely used in the US Army. This trailer was made in the form of a frame with a floor, to which a two-axle undercarriage was attached from below. The latter was a bogie with leaf spring suspension. A towing device was attached to the front of the trailer frame. To stabilize the platform in the parking lot or when performing some operations on the corners of the trailer, there were jacks.
GEMSS system, right side view. Photo Tankograd.com
A launcher was placed in the front of the trailer, which provided the release of mines. Its "nozzle" was directed backward in the direction of travel: the mining system scattered explosive devices behind it. Behind the launcher was a large cylindrical casing with a pair of magazines for transporting mines and the means for supplying them to the launcher. At the rear of the trailer, a casing was provided with its own power plant, which was responsible for the operation of all other devices. The main body of the installation was made of low-thickness armor steel and provided protection against bullets and shrapnel.
The launcher from the M128 system had a horseshoe-shaped casing with stiffening ribs, inside which a rotor with its own electric drive was placed. From the bottom back on the casing, a branch pipe was provided for supplying mines from the store, and above it, a branch pipe for ejecting mines. The installation was placed on a special support with some inclination to the right (relative to the direction of movement). The support was equipped with its own drive, with the help of which it had to constantly rotate the launcher around a vertical axis.
For storage and transportation of mines, a pair of drum magazines were used, placed in a transverse cylindrical body. On the sides of such a body were magazines, in the center - their drives and the system for supplying mines to the launcher. Each store contained 400 minutes (total ammunition - 800 minutes). The mines were placed inside a rotating feeder-impeller and were sequentially fed to a conveyor belt for feeding to the launcher.
Diagram of an anti-tank mine of the FASCAM family. Figure Fas.org
All the main mechanisms of the M128 GEMSS mining system were electrically driven. The energy for the electric motors was generated by its own low-power diesel generator located in the rear of the trailer. Also, the system included a remote control, with the help of which the calculation could control its operation.
In terms of overall dimensions, the M128 mining system corresponded to the base trailer. The total height, taking into account all the special equipment, is slightly more than 2.5 m. The own weight of the product is 4773 kg. Gross weight with ammunition load of 800 mines - more than 6350 kg. The trailer was allowed to be towed by any available equipment with the required characteristics. There were no restrictions on the speed of towing on the highway. Rough terrain speed was influenced by a number of factors.
FASCAM mines
The M128 system was supposed to provide the installation of several types of mines from the FASCAM (Family Of Scatterable Mines) line. Depending on the task, military engineers had to scatter M74 anti-personnel fragmentation mines, M75 cumulative anti-tank mines, or practical M79 on the ground. All these products had a unified cylindrical body with a diameter of 119 mm and a height of 66 mm.
M128 during operation. Mines flying away are visible at the top of the frame. Shot from newsreel
The M74 anti-personnel mine weighed 1.4 kg and carried 410 g of explosives. The anti-tank M75 had a charge of 585 g. The practical ammunition weighed 1.6 kg and could simulate the ballistic parameters of combat. Instead of a charge, he carried a weight simulator.
Operating principle
The principle of operation of the GEMSS system was quite simple. The installation of remote mining using a tractor should have been carried out along the front. The speed of movement was determined in accordance with the required density of mining. Slower speed provided a shorter distance between mines, while its growth contributed to a decrease in density. Using the control panel, the operator could change other parameters of the future minefield.
The feeders of the two drum magazines had to constantly rotate and bring mines to a special conveyor. He supplied ammunition to the launcher. Inside the latter there was a rotating rotor with its own drive. Under the action of the rotor, the mine had to pass along the guide wall of the installation body. The high rotor speed generated centrifugal force. Then the mine fell to the upper branch pipe and flew out under the action of this force.
The energy of the rotor was enough to disperse the throwing of the mine to a distance of 50-70 m, depending on its type and mass. The rate of fire of such a system could be set by the operator; its maximum value is 4 mines per second.
View from a different angle. You can see a flying mine. Shot from newsreel
During operation, the launcher could be fixed in one position or make turns in different directions. Due to this, mining of a strip of arbitrary width was ensured. In the first case, mines were scattered in a strip no more than a few meters wide. With the maximum deviation of the launcher, the mine flew 30-50 m from the line of movement.
Using two standard magazines with 800 mines and observing the optimal speed, the M128 installation could organize a barrier with dimensions of 1000x60 m in one pass. By changing the rotor speed or the trailer's speed, it was possible to influence the parameters of the minefield. At the same time, excessive speed or reduced rate of fire could damage the density of the installation of mines.
In service
The FASCAM family of mines was put into service in 1975. Soon, the M128 GEMSS remote mining installation was also adopted. Over the next few years, dozens of such products were manufactured in the interests of the US engineering forces. The new equipment was distributed between the sapper battalions of the tank and motorized rifle divisions. This unit was supposed to have 8 units.
The first new engineering systems were received by the formations stationed in Europe. According to known data, American formations at European bases received and deployed 69 GEMSS installations. A similar number of such devices remained in the United States. Engineering equipment was regularly used as part of combat training activities. The crews of the M128 went to the fields of training battles and carried out conditional mining of the terrain using inert M79 mines. During their service, the M128 systems never had to participate in a real operation and organize mine-explosive obstacles in the enemy's path.
Application of the M128 system by a field engineer. Diagram from Field Manual FM 20-32
Active operation of GEMSS systems continued until the early nineties, when it was decided to replace them with other samples. The developed means of mining were inferior to the M128 in terms of the size of the ammunition load and the main characteristics, but they were lighter and more compact. Since 1991, new means of remote mining, compatible with the mines of the FASCAM family, have begun to enter service with US engineering units. The appearance of these products gave rise to the gradual decommissioning of obsolete GEMSS.
The process of decommissioning and decommissioning engineering systems lasted several years and ended in 1995. According to various sources, some of the M128 GEMSS products were retained and sent to storage. Other mining systems were disposed of as unnecessary.
Advantages and disadvantages
The M128 Ground Emplaced Mine Scattering System towed remote mining system was an interesting piece of engineering technology capable of providing fast and high-quality organization of mine-explosive obstacles. The installation was distinguished by a rather simple design, but at the same time it carried a large supply of mines, could use ammunition of various types and disperse them over a large area. All these factors led to the fact that at one time the M128 was put into service and received a certain distribution.
However, the GEMSS product was not without its drawbacks. Its main problem could be considered the size and weight, which imposed certain restrictions on the operation. So, the installation needed a tractor capable of towing a trailer weighing more than 6 tons, including over rough terrain. The presence of a large and heavy trailer to some extent impaired the mobility of a sapper battalion or company. When mining in the path of the enemy, the trailer could attract attention and become an easy target.
It is known about some difficulties associated with the use of a centrifugal launcher and drum magazines. As part of these devices, a significant number of moving parts were present, which led to the risk of damaging the mine at different stages of the mechanism's operation. In addition, there were problems with the reliability of the stores.
The mines of the FASCAM line used to some extent complicate the operation of the installation. Due to the characteristic method of operation, the M128 system could not be used in some areas. Mines could not be thrown on solid ground or other surfaces that could damage them if dropped. The presence of vegetation, snow cover or other obstacles interfered with the normal laying, and could also lead to premature self-destruction of ammunition.
The M128 GEMSS remote mining system was one of the most interesting examples of US engineering technology. It implemented unusual ways of working with ammunition, which ensured high performance. However, obtaining the desired opportunities was associated with a number of difficulties and problems. In this regard, the M128 gave way to newer mining systems that use different principles of operation.
