The 4AHM-100, AHM-200, AHM-200-1, AHM-200-2, PMN-150, and PMN-250 are Bulgaria

Bulgaria

Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...

n directional fragmentation mines that can be used with proximity fuze

Proximity fuze

A proximity fuze is a fuze that is designed to detonate an explosive device automatically when the distance to target becomes smaller than a predetermined value or when the target passes through a given plane...

s to function as anti-helicopter mines.

Description

The systems were developed by the Institute of Metal Science and are based around electronic fuzes with broadly similar functionality. The fuzes use two sensors. The first, an acoustic sensor, arms the mine as a helicopter approaches. The second sensor is a radar

Radar

Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...

 sensor, which locates the target and triggers the mine at the optimal point. The mines all use a number of large Misznay Schardin effect warheads to project large numbers of fragments to an effective range of around 200 meters. Jane's Mines and Mine Clearance speculates that IFF

Identification friend or foe

In telecommunications, identification, friend or foe is an identification system designed for command and control. It is a system that enables military and national interrogation systems to identify aircraft, vehicles, or forces as friendly and to determine their bearing and range from the...

 could be integrated into the fuse circuit to discriminate against friendly aircraft.

PMN-150 and PMN-250

The PMN-150 and PMN-250 are large directional fragmentation mines that scatter fragments in a 60 degree horizontal arc. The PMN-150 produces approximately 1,500 fragments that have an effective range of 150 meters. The PMN-250 is a larger mine which produces 2,100 fragments that have an effective range of 250 meters. The mines have a number of electronic fuzes available including three microwave fuzes, an acoustic fuze and a seismic sensor. The mines can be remotely triggered or deactivated.

Anti-Transport Mine

The "Anti-Transport Mine" is a large circular directional fragmentation mine that uses an internal fragmentation matrix and five Misznay-Schardin plates

Misznay-Schardin effect

The Misznay–Schardin effect, or platter effect, is a characteristic of the detonation of a broad sheet of explosive. The explosive blast expands directly away from the surface of an explosive...

. The fragmentation matrix produces a large number of small fragments, and the Misznay Schardin plates produce large fragments that can penetrate armoured vehicles.

The mine appears to be based on the PMN-250 mine, and the mine is likely to have an effective range of 250 meters.

4AHM-100

The 4AHM-100 uses four 30 kilogram mines with a single central sensor. The mines are triggered simultaneously when the sensor detects a target inside the effective footprint of the mines. The mine is currently at the prototype stage.

AHM-200

The AHM-200 weighs 35 kilograms and contains 12 kilograms of TNT. The mine's warhead has two sections, a large rectangular warhead with a pre-notched fragmentation liner that produces 1,960 fragments, and a secondary warhead with five Misznay Schardin plates that produce large self-forging fragments. The fragments scatter in an arc of 20 degrees to an effective range of 200 meters, and will penetrate 10 millimeters of armour at 100 meters.

AHM-200-1

The AHM-200-1 weighs 90 kilograms. Like the AHM-200 it consists of two sections, a large circular fragmentation warhead with a filling of ball bearings, and a horizontal section with five Misznay Schardin effect plate charges. The two sections are mounted on a sturdy tripod with a sensor mounted above that contains a Doppler radar fuze and an acoustic fuze. The mine has an effective range of about 100 meters.

AHM-200-2

The AHM-200-2 weighs 90 kilograms, and is similar to the AHM-200-1, except that it uses a rectangular fragmentation warhead that produces 1,960 fragments.