PMN-3 Antipersonnel Mine

Design and principle of operation

The PMN-3 mine consists of a body (with an integral electromechanical fuze), as well as an explosive charge and a power source.

The mine has a plastic body (pos. 1). It contains a socket for the power source (pos. 12) and a compartment with a removable cover (pos. 17) for the explosive charge (pos. 25). The cover is removed from the compartment by means of a green nylon tape (pos. 9). A light indicator (pos. 8) is located on the side surface of the body. Next to the handle (pos. 11) of the self-destruct time selector, the mine self-destruct time markings are applied, and on the base side of the mine there is an outline of the power source with “+” and “-” signs.

The integral electromechanical fuze consists of: an activation unit with a safety pin (pos. 15); a pressure target sensor covered with a rubber cap (pos. 4); an anti-removal element (tilt sensor) (pos. 14); an electronic unit (pos. 5) with a light indicator (pos. 8); a self-destruct time selector (pos. 10) and a safety-and-firing mechanism (PIM).

The activation unit consists of a spring-loaded plunger (pos. 16) with a plate and contacts. In the transport position of the mine, the plunger is held by the safety pin (pos. 15), inserted into the slot of the plunger. For ease of removal, the pin is fitted with a red nylon tape.

The pressure target sensor consists of a spring-loaded crosspiece (pos. 2) with a screw and a contact (pos. 3). The rubber cap (pos. 4), which covers the crosspiece, is secured on top of the mine body by a cover (pos. 6) and a union nut (pos. 7).

The tilt sensor (pos. 14) (ball switch) ensures actuation of the mine when it is tilted by more than 90°.

The electronic unit (pos. 5) is a circuit board with radio components mounted on it and performs the functions of the delayed arming mechanism, indication unit, anti-disarming device, firing device, and self-destruct mechanism. It provides the delayed arming time and transition of the mine to the armed position, as well as actuation if an attempt is made to remove the power source or upon expiry of the self-destruct period.

By flashing for (4.5±1.5) min (after the safety pin is pulled), the light indicator (pos. 8) signals that the power source is connected and that the electronic unit is serviceable.

The self-destruct time selector (pos. 10) allows one of five mine self-destruct time settings (12 h; 1-2-4-8 days) to be set by turning the handle (pos. 11).

The safety-and-firing mechanism is a dual-igniter, safety-type mechanism consisting of: ЭВ-1 (pos. 24) and ЭВ-2 (pos. 19) electric igniters of the НХ-ПЧ-А type; a slider (pos. 22); contacts (pos. 18), a striker (pos. 20); and an МГ-8-Т detonator (pos. 21). In the transport position of the mine, the slider, being restrained from movement by the shear pin (pos. 23), provides a break in the mine firing train. When the ЭВ-1 electric igniter functions, the slider moves, shears the pin, and closes the contacts (pos. 18) of the ЭВ-2 electric igniter firing circuit. The ЭВ-2 electric igniter functions, the striker pierces the МГ-8-Т detonator, which detonates and transfers detonation to the booster detonator (pos. 26) and the explosive charge (pos. 25) of the mine.

The charge (pos. 25) is made of pressed A-IX-1 explosive and has a booster detonator (pos. 26) made of PETN explosive with a mass of 1.1 g.

The power source (pos. 12) is placed in a special socket closed with a cover (pos. 13).

The mine packaging contains: a screwdriver-type key and a resistor. The key is required for unscrewing/screwing in the plug of the power source socket, as well as for conveniently moving the self-destruct selector handle from one position to another. The 1.6 kΩ resistor is used when checking the serviceability of the power source.

When the safety pin of the activation unit (pos. 2) is pulled, the contact (pos. 3) closes, the power source (pos. 1) is connected to the indication unit (pos. 5) and the delayed arming mechanism (pos. 6), the light indicator (pos. 4) begins to flash and illuminate for (4.5±1.5) min, and then goes out. Upon expiry of the delayed arming time (8.5±1.5 min after removal of the safety pin), the power source is connected to the self-destruct mechanism (pos. 8), the firing device (pos. 9), and the anti-removal device (pos. 10). The mine transitions to the armed position. When pressure is applied to the target sensor (pos. 11) or when the position of the mine changes by more than 90° (tilt sensor pos. 12), the firing device (pos. 9) and the safety-and-firing mechanism (pos. 13) function, and as a result, the explosive charge (pos. 14) detonates. Detonation of the mine is also initiated when the anti-removal device (pos. 10) functions during an attempt to disarm the mine by removing the power element or upon expiry of the time set on the self-destruct mechanism (pos. 8).

Safety precautions

Mines are transported to the emplacement site in their standard packaging.

Before use, the mine must be inspected to ensure the presence of the safety pin and the absence of mechanical damage to the mine body.

It is prohibited to

1. Allow mines, with or without packaging, to fall from a height of more than 1.5 m (such mines are prohibited from use).
2. Remove the safety pin when the charge is installed in the mine.
3. Install the charge in the mine if the light indicator does not illuminate after the safety pin is removed or illuminates continuously (does not flash).
4. Remove the power source from the mine if the safety pin has been removed.
5. Move the mine to the emplacement site after the light indicator has stopped flashing.

Attention! The mine is emplaced only with the pressure sensor facing upward.

After removing the pin, the mine must be held in the hand with the charge compartment facing away from oneself.

Mines in which, after removal of the pin, the light indicator does not illuminate or illuminates continuously are not permitted for use and are subject to destruction.

Preparation and emplacement

PMN-3 mines are emplaced manually

• In summer, in the ground or on the ground with concealment by soil or vegetation.
• In winter, on the surface of the ground or in snow with concealment by snow.

In hard compacted snow, mines are emplaced in the same manner as on the ground.

Before emplacement, it is necessary to

1. Open the packaging.
2. Inspect the mine and ensure the presence of the safety pin, as well as the absence of mechanical damage to the mine body.
3. Set the self-destruct time selector to the required position.
4. Check and install the power source in the mine.

To check and install the power source, it is necessary to

1. Connect the 1.6 kΩ resistor and voltmeter in parallel to the power source; the voltage must be not less than 8.75 V.
2. If the voltage is less than 8.75 V, it is necessary to briefly short-circuit the positive and negative contacts of the power source 1-2 times (for no longer than 1 s).
3. Check the voltage of the power source again; if it is less than 8.75 V, replace the battery.
4. Unscrew the plug of the power source socket.
5. Insert the power source into the socket as indicated on the mine body.
6. Screw in the plug.

Emplacing the mine in the ground

1. Dig a hole to the diameter of the mine, 3-4 cm deep.
2. Using the green tape, remove the cover from the charge compartment.
3. Holding the mine with one hand and directing its charge compartment away from oneself, remove the safety pin.
4. Verify normal operation of the mine by the flashing of the light indicator.
5. Install the charge in the mine and close the compartment with the cover.
6. Place the mine in the hole with the target sensor facing upward.
7. Conceal the mine and, no later than 3 min (after removal of the safety pin), leave the mine emplacement site.

In winter, when the snow layer is up to 10 cm, the mine is emplaced on the ground surface. When the snow layer is more than 10 cm, the mine is emplaced in the snow so that the concealment layer of snow above the mine is not more than 5 cm.

Removing and disarming PMN-3 mines is prohibited!

Emplaced mines are destroyed by detonating explosive charges with a mass of 0.2 kg placed next to the mine, or by repeated passage over the minefield by tanks equipped with mine rollers.