The DM 1274 anti-tank mine (also DM 1233, DM 1399, AT2) was created and adopted by the Bundeswehr in 1980 for remote mining by MARS2 MLRS systems and mine laying installations and was used by the armed forces of Great Britain, Germany and Norway. Externally, they can be distinguished: DM1233 and DM1399 have parachutes (of different types) attached to the top of the hull, while DM1274 (DM1274A1) does not have them. In September 2022, Germany transferred 2 MARS 2 MLRS installations and 200 shells to them to Ukraine. At the same time, minefields of these mines were discovered in the Kherson region. In addition, these mines were also discovered near Donetsk.
Designed to disable enemy tracked and wheeled vehicles. Enemy vehicles are damaged by exploding a shaped charge under the bottom of the vehicle.
Structurally, the mine is a corrugated body (1) made of green plastic. Twelve folding spring-loaded steel legs (2) are inserted into the longitudinal grooves of the body and are hingedly fixed at the lower ends. These legs, when folded, ensure the vertical position of the mine on the ground. In the transport position and during the flight of the mine to the installation site, these legs are held in place by a steel tension band (3) that covers the mine body. This tension band is locked and held in this position by a special locking fungus that comes out of the mine and is part of the protection system. After the mine is thrown out of the cassette and falls to the ground, and the process of transferring the mine to the combat position begins, the fungus will release the locking band. Since the band is springy, it will unfold in a line and separate from the mine. The released paws will forcefully fold back and place the mine body in a vertical position. Organizationally, the mine consists of two main blocks: 1. Warhead. 2. Functional part (10). The warhead is a thin-walled steel case (4), inserted into the plastic mine body, filled with a composition of hexogen (94.5%), plasticizer (4.5%) and graphite (1%) (6). The code of this BP according to the German nomenclature is R 8151. The total mass of the explosive is 780 grams, which provides penetration of up to 140 mm of armor. From above, the case is closed with a plate (5) made of red copper, which forms a cumulative recess of a hemispherical shape. From below, the case has a cup (7) for the intermediate detonator of the blasting device. A cap (8) made of elastic plastic is fixed on top of the body. It is spring-loaded from the inside by two springs (9). In the mine's transport position (when it is in the cassette), this cap is pressed inside the cumulative recess, which allows you to reduce the distance between the mines in the cassette. After leaving the cassette, this cap is pushed out by a spring. The role of the cap is twofold: first, it prevents the mine from lying on the ground (in other words, standing "on its butt") until the upper part of the body's legs are thrown back. The mine, thanks to the cap, will definitely lie on its side (unless it accidentally falls on the bottom). The second task of the cap is to maintain free space above the cumulative recess for the entire duration of the mine's combat operation. The main target sensor is the S3 sensor, located in the upper part of the mine body, and is an electric contactor with an antenna that rises above the mine to a height of about 45 cm. The antenna is a steel spring wire. In the transport position (when the mine is in the cassette and until the legs are folded back), the antenna (13) is wound around the upper part of the body and is held in place by the legs (2). As soon as the legs are folded back in the process of bringing the mine into combat position, they will simultaneously release the antenna, which, due to its springiness, will straighten and take a vertical position. The sensor is electrically connected to the DM 1234 fuse (11), located in the functional part of the mine (10). When the target (tank or other vehicle) deflects the antenna by more than 20 degrees, the sensor will send a signal to the fuse via wires running inside the body. The electronic part of the fuse processes the signal and, depending on the characteristics of the signal, either gives a command to explode or rejects the signal. To give a command to explode, the antenna must be deflected for a certain duration. The fuse does not react to short-term deflections and swings caused by gusts of wind, impacts of flying objects (clods of earth, fragments, bullets, etc.), etc. The functional part of the mine is located in the lower part of the case and, in turn, is divided into two main units. The lowest unit is the battery pack. It contains two lithium batteries that power the electronic and electrical circuits of the fuse located above the battery pack. When the mine is stored in the cassette, the batteries are disconnected from the mains. At the beginning of the process of ejecting the mine from the sub-cassette tube, special devices (activators) located near the mains of the batteries connect them to the mains of the fuse. And from this moment on, the batteries become the power source. It is impossible to remove the batteries from the unit. In addition to the batteries and activators, the battery unit contains the S7 sensor, which registers ground shaking and shock waves from explosions of other ammunition, and briefly disables the fuse electronics, thus preventing unauthorized mine explosion. This ensures the mine's resistance to close bursts of any ammunition, and in particular demining charges. The battery unit also contains a plug to which the programming cable is connected. This cable is used to set the mine's combat time from the mine detector's control panel. The wires from the plug are led through the battery unit to the electronic part of the fuse. Above the battery unit is the DM 1234 fuse, which is organizationally divided into a mechanical part and an electronic circuit. The mechanical part of the fuse performs the task of preventing unauthorized explosion in case of false activation of the electronics before the mine is in the combat position. This is achieved by the fact that a safety bracket protrudes from the mine body and rests against the wall of the sub-cassette tube, which keeps the initiation circuit (electric detonator, detonation amplifier, main charge) in the open state until the mine flies out of the sub-cassette tube, touches the ground, and the program for bringing the mine into the combat position is worked out. The electronic circuit of the fuse is turned on after the mechanical part has worked out the removal from the fuse. The electronic circuit first of all monitors the battery voltage and, in the event of a decrease in the battery voltage below a certain level, gives a command for the mine to self-destruct in advance. This eliminates the failure of the mine due to a power failure (old, leaking or frozen batteries). At the same time, if by the time the mine is brought into combat position, the batteries cannot, for any reason (expired storage period, frozen, etc.), provide the voltage necessary for the operation of the electronic circuit, the mine will completely fail. However, it is impossible to determine this externally, and all that remains is to wait for the doubled maximum combat operation period (192 hours). If the position of the mine in combat position changes (movement, tilt), this is registered by the S7 sensor, and the electronics give a command to detonate the mine. This prevents manual passage through the minefield.
The process of bringing a mine into combat position: Mine in the cassette tube. From the Scorpion minelayer control panel, a signal is sent to the mine via a cable network, which sets the time of the mine's combat operation. When the "Fire" button is pressed on the Scorpion minelayer control panel, the mine's capacitors are charged from the vehicle's on-board network and at the same time the mine's batteries are connected to the electronic part of the fuse. After a split second, the pyrotechnic cartridge drops the cover of the cassette tube and then the ejector charge throws out five mines located in one cassette tube. After the mine has left the tube, its safety bracket, which previously rested against the wall of the tube, pops out, which makes it possible to further execute the program for bringing the mine into combat position. From this moment, the mine's combat operation time begins to count down. During the flight, the spring lifts the mine cap outward, due to which the mine, once on the ground, will either lie on the ground on its side or bottom. The cap will not allow it to lie on the ground upside down. 5 minutes after the mine leaves the tube, the program for bringing the mine into combat position will complete its work. At the same time, the last points of the program, which take 10–11 seconds, will be executed only if the mine hits the ground before that. During the execution of the program for bringing it into combat position, the pyro cartridge opens the spring-loaded tape that held the spring-loaded legs and simultaneously returns the detonator holder with the detonator to the combat position. The released legs, due to their springiness, sharply fall to the sides and raise the mine into combat position (if it was lying on its side until this moment). In the future, these legs provide the mine with a stable vertical position. From this moment on, the mine is in combat mode and will explode if it is tilted or its antenna is caught by the vehicle body. The combat use of mines is possible only with the Scorpion minelayer. For this, five cassettes are installed in the Scorpion minelayer launch container. The minelayer has six launch containers in total. The minelayer thus carries 600 DM1274 (DM1274A1) mines. The mines in the cassette tube are stacked one after the other and are separated by plate and conical springs that are in a compressed state. Behind the first mine is an ejector powder charge weighing 35 grams, which pushes all five mines out of the cassette tube at once (however, not simultaneously from all cassette tubes of the cassette, but sequentially at certain intervals set on the minelayer control panel). Thanks to this ejection system, all five mines fall on the terrain in a group in one line at distances from the minelayer: Mine 1 — 10–18 meters, Mine 2 — 17–23 meters, Mine 3 — 23–29 meters, Mine 4 — 29–35 meters, Mine 5 — 34–42 meters. Of course, the minelayer’s launch containers are installed at an angle to the machine’s axis of movement, which provides a kind of distribution of mines on the terrain. Figuratively speaking, if the machine’s axis of movement is taken as the trunk of a Christmas tree, then the groups of mines form the branches of this Christmas tree.
Defused mines are destroyed using two charges of explosives weighing 500 grams each, which are applied to the mine body. In this case, it is necessary to withstand at least 96 hours from the moment of detection of such a mine. Destruction of defused mines by shooting from small arms or automatic guns, as well as using mine trawls, is prohibited due to the ineffectiveness of such methods. A mine explosion is possible in the following cases: 1. Target impact on the antenna: sensor S3 is triggered. 2. Change of position: attempt to tilt the mine or if it has not assumed a vertical position after falling (sensor S1/S7). 3. Expiration of the term: self-destruction timer is triggered. 4. Voltage drop: the control device has recorded a decrease in the energy of the power sources below the threshold. The explosion does NOT occur if: 1. The antenna is affected by short-term random factors (wind, occasional blows of branches). 2. An electronics or power failure occurred before it was brought into combat position. 3. The mechanical part of the fuse failed during activation. 4. The mine is affected by ground shaking or a shock wave from nearby explosions (thanks to the S7 sensor).