The PMN () series of blast

anti-personnel mine Anti-personnel mines are a form of mine designed for use against humans, as opposed to anti-tank mines, which are designed for use against vehicles. Anti-personnel mines may be classified into blast mines or fragmentation mines; the latter may ...

s were designed and manufactured in the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

. 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 filling when compared to most other anti-personnel landmines. For comparison, most anti-personnel blast mines (e.g. the

VS-50 VS-50 (suborbital rocket VS-50) is a joint development of sounding rocket from the Institute of Aeronautics and Space (IAE) and German Aerospace Center (DLR). Characteristics It is a suborbital vehicle that uses solid fuel, having two stages: ...

) contain around 50 grams 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 ...

, which typically destroys all or part of a victim's foot. In marked contrast, a PMN-1 contains 249 grams of explosive which can easily destroy a victim's entire leg (frequently requiring amputation high above the knee) in addition to inflicting severe injuries on the adjacent limb, which may also require some form of amputation due to blast injury. The majority of anti-personnel mine victims (e.g. those who step on an M14 mine containing 29 grams of explosive) have a very high probability of survival, though inevitably they suffer permanent disability regarding their gait. 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 case (brown or black in colour) with a black rubber pressure-plate and contains

TNT Trinitrotoluene (), more commonly known as TNT, more specifically 2,4,6-trinitrotoluene, and by its preferred IUPAC name 2-methyl-1,3,5-trinitrobenzene, is a chemical compound with the formula C6H2(NO2)3CH3. TNT is occasionally used as a reagen ...

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. 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 with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...

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 detonator, firing both it and the adjacent

tetryl 2,4,6-Trinitrophenylmethylnitramine commonly referred to as 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 ...

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 s ...

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 ...

. *Height: 57 mm *Diameter: 112 mm *Main charge weight: 240 g

(initiated by a 9 gram

) *Total weight: 600 g *Fuze: MD-9 (stab-sensitive) *Operating pressure: 5.8 kg 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/

based explosive that is quite similar to

Composition B Composition B, colloquially Comp B, is an explosive consisting of castable mixtures of RDX and TNT. It is used as the main explosive filling in artillery projectiles, rockets, land mines, hand grenades and various other munitions. It was also ...

. 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 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 with ...

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 ( RDX/

) *Total weight: 420 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 booster charges. It is made of pentaerythritol tetranitrate (PETN) phlegmatized with trinitrotoluene (TNT) by melt casting.B. M. Dobratz & P. C. C ...

. 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 fuze 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 ( RDX/

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

Render-safe procedure

It is considered extremely dangerous to disarm PMN mines by removing the fuze, 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 MC-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

deminer 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 contr ...

s. 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 ''In situ'' (; often not italicized in English) is a Latin phrase that translates literally to "on site" or "in position." It can mean "locally", "on site", "on the premises", or "in place" to describe where an event takes place and is used in ...

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

Iraq Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to the north, Iran to the east, the Persian Gulf and K ...

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

Variants

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

Myanmar Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...

* 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 (; bg, България, Bǎlgariya), officially the Republic of Bulgaria,, ) is a country in Southeast Europe. It is situated on the eastern flank of the Balkans, and is bordered by Romania to the north, Serbia and North Macedo ...

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 A sympathetic detonation (SD, or SYDET), also called flash over or secondary/secondaries (explosion), is a detonation, usually unintended, of an explosive charge by a nearby explosion. Definition A sympathetic detonation is caused by a shock wav ...

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. Alfred N ...

RDX 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 begins to ...

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

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