The PMN () series of blast

anti-personnel mine An anti-personnel mine or anti-personnel landmine (APL) is a form of land mine, mine designed for use against human, humans, as opposed to an anti-tank mine, which target vehicles. APLs are classified into: blast mines and fragmentation mines; ...

s were designed and manufactured in the

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. They are one of the most widely used and commonly found devices during

demining Demining or mine clearance is the process of removing land mines from an area. In military operations, the object is to rapidly clear a path through a minefield, and this is often done with devices such as mine plows and blast waves. By cont ...

operations. They are sometimes nicknamed "black widow" because of their dark casings.

PMN-1

The design of the PMN-1 mine dates from the late 1950s. It is particularly deadly because it contains an unusually large

explosive An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An ex ...

filling when compared to most other anti-personnel landmines. For comparison, most anti-personnel blast mines (e.g. the VS-50) contain around of

high explosive An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An exp ...

, which typically destroys all or part of a victim's foot. In marked contrast, a PMN-1 contains of explosive which can easily destroy a victim's entire leg (frequently requiring

amputation Amputation is the removal of a Limb (anatomy), limb or other body part by Physical trauma, trauma, medical illness, or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as cancer, malign ...

high above the knee) in addition to inflicting severe injuries on the adjacent limb, which may also require some form of

due to

blast injury A blast injury is a complex type of physical trauma resulting from direct or indirect exposure to an explosion. Blast injuries occur with the detonation of high-order explosives as well as the deflagration of low order explosives. These injuri ...

. The majority of anti-personnel mine victims (e.g. those who step on an M14 mine containing of explosive) have a very high probability of survival, though inevitably they suffer

permanent disability Permanent may refer to: Art and entertainment * ''Permanent'' (film), a 2017 American film * ''Permanent'' (Joy Division album) * "Permanent" (song), by David Cook *"Permanent", a song by Alex Lahey from ''The Answer Is Always Yes'', 2023 Other ...

regarding their

gait Gait is the pattern of Motion (physics), movement of the limb (anatomy), limbs of animals, including Gait (human), humans, during Animal locomotion, locomotion over a solid substrate. Most animals use a variety of gaits, selecting gait based on s ...

. However, the amount of explosive inside a PMN-1 mine is so large that the risk of victims dying is significantly greater and, assuming that they survive their injuries, the degree of disability inflicted is much more severe. These mines are palm sized and cylindrical in shape. The PMN-1 has a

bakelite Bakelite ( ), formally , is a thermosetting polymer, thermosetting phenol formaldehyde resin, formed from a condensation reaction of phenol with formaldehyde. The first plastic made from synthetic components, it was developed by Belgian chemist ...

case (brown or black in colour) with a black rubber pressure-plate and contains

TNT Troponin T (shortened TnT or TropT) is a part of the troponin complex, which are proteins integral to the contraction of skeletal and heart muscles. They are expressed in skeletal and cardiac myocytes. Troponin T binds to tropomyosin and helps ...

explosive. The PMN-1 mine is armed by removing a steel ring-pull at the end of the horizontal fuze. When in position, the pin on the end of the ring-pull holds a spring-loaded striker back from the stab-

detonator A detonator is a device used to make an explosive or explosive device explode. Detonators come in a variety of types, depending on how they are initiated (chemically, mechanically, or electrically) and details of their inner working, which of ...

. Pulling out the ring-pull starts an arming delay, which comprises a thin steel wire (held under tension by the spring-loaded striker) which must cut through a small strip of

lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

before it is freed. The process of cutting through the lead strip takes between 2 and 12 minutes, depending on ambient temperature. After the wire has completely cut through the lead strip, the spring-loaded striker is freed and slides forward a few millimetres before stopping, blocked by the sliding gate of the pressure plate mechanism. At this point the mine is fully armed i.e. the only thing holding back the spring-loaded striker from the stab-detonator is a weak creep-spring on the pressure plate mechanism. Subsequently, any downward pressure on the pressure plate (i.e. when someone steps on the mine) overcomes the upward pressure of the creep-spring and pushes down the sliding gate that holds back the spring-loaded striker. This action frees the striker which flips forward into the stab

, firing both it and the adjacent

tetryl 2,4,6-Trinitrophenylmethylnitramine or tetryl ( C7 H5 N5 O8) is an explosive compound used to make detonators and explosive booster charges. Tetryl is a nitramine booster explosive, though its use has been largely superseded by RDX. Tetryl is a ...

booster Booster may refer to: Amusement rides * Booster (Fabbri ride), a pendulum ride * Booster (HUSS ride), an evolution of the Breakdance ride * Booster (KMG ride), a pendulum ride Arts, entertainment, and media Fictional characters * Booster, a cha ...

which triggers

detonation Detonation () is a type of combustion involving a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it. Detonations propagate supersonically through shock waves with ...

of the main

explosive filling. It is not a

blast resistant mine A blast resistant mine is a landmine (intended for anti-tank or anti-personnel purposes) with a fuze which is designed to be insensitive to the shock wave from a nearby explosion. This feature makes it difficult or impossible to clear such mines u ...

. *Height: *Diameter: *Main charge weight:

(initiated by a 9 gram

) *Total weight: *Fuze: MD-9 (stab-sensitive) *Operating pressure: Image:PMN-2_mine.jpg, Two PMN-1 mines: the first example is complete, the other shows the appearance of a PMN-1 after it has detonated Image:PMN Striker Assy.jpg, The striker assembly from a PMN-1 showing the

-shear arming delay. This assembly would be located under the round knurled cap on the right in the picture above

PMN-2

The PMN-2 mine casing is made from injection-molded plastic. In general, the color is leaf-green, but occasionally brown examples may be encountered. The top of the mine has a black rubber X-shaped pressure plate. The filling is an

RDX RDX (Research Department Explosive or Royal Demolition Explosive) or hexogen, among other names, is an organic compound with the formula (CH2N2O2)3. It is white, odorless, and tasteless, widely used as an explosive. Chemically, it is classified ...

based explosive that is quite similar to

Composition B Composition B (Comp B), also known as Hexotol and Hexolite (among others), is a high explosive consisting of castable mixtures of RDX and TNT. It is used as the main explosive filling in artillery projectiles, rockets, land mines, hand grenade ...

. As with the PMN-1, the PMN-2 has an unusually large explosive filling when compared to many other anti-personnel landmines. One significant difference between the PMN-1 and PMN-2 is that the PMN-2 (a mid-1970s design) contains a more modern

fuze In military munitions, a fuze (sometimes fuse) is the part of the device that initiates its function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fu ...

with an integral baffle beneath the pressure plate. This and the X-shaped design of the pressure plate makes the PMN-2 much more resistant to traditional explosive mine countermeasures, which use sudden overpressure to

detonate Detonation () is a type of combustion involving a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it. Detonations propagate supersonically through shock waves wit ...

mines. It can therefore be regarded as a

. In contrast, the PMN-1 (a 1950s design) can successfully be cleared by such methods. The PMN-2 fuze features an arming delay of approximately 60 seconds. When the arming key is rotated and removed from the mine, the arming pin is sheared. This allows the air-bellows inside the mine to be inflated by the compression spring, which in turn lifts a “safety” bar from the path of the slide, unblocking its travel. The arming delay on a PMN-2 is significantly shorter than that of a PMN-1. *Height: 53 mm *Diameter: 120 mm *Main charge weight: 100 g TG-40 (

) *Total weight: 440 g *Fuze: MD-9 (stab-sensitive)

PMN-4

The PMN-4 is a delay-armed, pressure-fired blast-mine. The pressure-plate is black and the body is reddish-brown or khaki. The black rubber pressure-plate has a plastic pressure "spider" concealed underneath, shaped like flower-petals. The diameter of the mine is 95mm and the height is 46mm. The explosive charge weight is 55 grams. This comprises 52 grams of 'TG-40' (a 40/60 TNT/RDX mixture) plus a 3 gram

pentolite Pentolite is a composite high explosive used for military and civilian purposes, e.g., warheads and explosive booster, booster charges. It is made of pentaerythritol tetranitrate (PETN) phlegmatized with TNT, trinitrotoluene (TNT) by melt casting.B ...

. The total weight of the mine is 300 grams. PMN-4 mines contain a significant amount of metal components, so they are readily detectable with a mine detector. Details of the

mechanism are scarce, though given that the PMN-4 was designed during the early 1980s, it is logical to assume that the fuze is more sophisticated and/or reliable than the fuze in the PMN-2 (a mid-1970s design) to compensate for having a smaller explosive filling with significantly reduced destructive power. Similarly, the PMN-4 is almost certainly a

due to the design of the flower-shaped pressure "spider" under the pressure-plate. Cross-sectional diagrams of the PMN-4 showing its components support the view that the PMN-4 is a more sophisticated design than the PMN-2. Examples of the PMN-4 have been encountered in Ukraine and Southern Syria. *Height: 42 mm *Diameter: 95 mm *Main charge weight: 50 g TG-40 (

) *Total weight: 300 g *Actuation force: 5–15 kg

Render-safe procedure

It is considered extremely dangerous to disarm PMN mines by removing the

, unless they have only recently been laid and are in good condition. Even if this is the case, what appears to be a standard PMN-1 mine may in fact be the PMN-3 or MS-3 versions, which feature an integral

anti-handling device An anti-handling device is an attachment to or an integral part of a landmine or other munition such as some fuze types found in general-purpose air-dropped bombs, cluster bombs and sea mines. It is designed to prevent tampering or disabling, ...

which is specifically designed to kill deminers. In any case it is very easy to boobytrap a standard PMN mine by attaching a pull-fuze to it, or by placing an ML-7 pressure-release antihandling device underneath. Therefore, the standard render-safe procedure for PMN mines is to destroy them

in situ is a Latin phrase meaning 'in place' or 'on site', derived from ' ('in') and ' ( ablative of ''situs'', ). The term typically refers to the examination or occurrence of a process within its original context, without relocation. The term is use ...

using a small explosive charge. Image:PMN AP-mine.JPEG, PMN-1 type mines found in

Iraq Iraq, officially the Republic of Iraq, is a country in West Asia. It is bordered by Saudi Arabia to Iraq–Saudi Arabia border, the south, Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq border, the east, the Persian Gulf and ...

(2003) Image:mine sweep.jpg, U.S. Army soldier with various PMN-1 mines near

Fallujah Fallujah ( ) is a city in Al Anbar Governorate, Iraq. Situated on the Euphrates, Euphrates River, it is located roughly to the west of the capital city of Baghdad and from the neighboring city of Ramadi. The city is located in the region ...

Variants

* Type 58: Chinese copy of the PMN-1. * MM 2: Burmese copy of the PMN-1 used in

Myanmar Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...

. * Gyata 64: Hungarian copy of the PMN-1. *

PM-79 mine The PM-79 is a small, circular Bulgarian blast-resistant anti-personnel mine, superficially similar to the Russian PMN. The mine uses a unique trigger design; on the top of the mine, beneath a thin rubber cover is a dish shaped pressure plate. Pr ...

Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...

n variant of the PMN-1. * MS-3: Has existed since at least 1973. It looks similar to the PMN-1, but has a small "blister" in the centre of the pressure-plate, incorporating a spring-loaded, pressure-release

. The explosive content is 310 grams of

. The total weight of a MS-3 is 630 g. An MS-3 requires a minimum load of between 5 and 6 kg on the "blister" to prevent detonation. As a result, armed MS-3 mines will always be encountered under some sort of heavy object, such as beneath an OZM bounding mine or sometimes an anti-tank mine to act as an

. Note that detonation of an MS-3 under an anti-tank mine may cause sympathetic detonation of the larger munition. Additionally, an MS-3 could simply be used as a conventional boobytrap device without being buried, for example deliberately planted inside a building or a vehicle with some form of weight on top such as a suitcase. * PMN-3: looks similar to the PMN-2, but incorporates a battery-operated tilt-switch

designed to kill/wound deminers. The explosive content is 80g

phlegmatized A phlegmatized explosive is an explosive that has had an agent (a phlegmatizer) added to stabilize or desensitize it. Phlegmatizing usually improves the handling properties of an explosive (e.g. when munitions are filled in factories.) Tr ...

i.e. RDX and

paraffin wax Paraffin wax (or petroleum wax) is a soft colorless solid derived from petroleum, coal, or oil shale that consists of a mixture of hydrocarbon molecules containing between 20 and 40 carbon atoms. It is solid at room temperature and melting poi ...

. The total weight of the PMN-3 is 600g. This mine has been encountered in

Chechnya Chechnya, officially the Chechen Republic, is a Republics of Russia, republic of Russia. It is situated in the North Caucasus of Eastern Europe, between the Caspian Sea and Black Sea. The republic forms a part of the North Caucasian Federa ...

References

External links

Cross-sectional view of PMN-1 mine showing firing mechanismAnimated cross-sectional view of a PMN-1 showing the arming and firing mechanisms in operationPMN-2 Dissection article (details its components and their operation)
fro
Ambidextrous Magazine (issue 4)
* *{{ORDATA, 6107, PMN-2
Exploded views of the PMN-1 & PMN-2 (Russian language website)Evaluation of a Silent Killer: the PMN Anti-Personnel Blast Mine
Anti-personnel mines Land mines of the Soviet Union