BTM-3 is an army vehicle for quickly laying ditches and trenches in category I-IV soils, that is, the machine is capable of tearing trenches in soils from sandy to frozen. It was created in the USSR in the 1970s for the engineering troops, but has found wide application in many civilian industries. It is used for irrigation and land reclamation works. The machine is mounted on the basis of a heavy artillery tractor AT-T. The working unit is a steel wheel with buckets that lowers behind the machine and rotates, digging a ditch. Star-shaped shafts are located on the sides of the wheel, which scatter the extracted soil to the sides.

Production of the BTM-3 commenced in 1957. It is officially designated as a “High-Speed Trenching Machine”. This machine was used by motorized and mechanized infantry units. Each Soviet motorized or mechanized division (10 000~13 000 soldiers) had 3 of these trenching machines. The BTM-3 was exported to Soviet allies. This trenching machine proved to be durable and reliable. Despite its military nature BTM-3 was also used by civilians for digging ditches, drains, and communication channels. There were also dedicated civilian versions with different rotor design. Successor of the BTM-3 became the BTM-4M Tundra.

This trench-digging machine has a large rotor with buckets at the rear. There are a total of 8 buckets, with 160 l capacity each. The rotor is lowered behind the vehicle and digs trenches. It takes around 5-7 minutes to prepare the machine for digging.

The BTM-3 can dig two main types of trenches. The basic trench is 1.1 deep and 0.9 m wide. The machine can also dig full-size trench that is 1.5 m deep and 1.1 m wide. In both cases width at the bottom of the trench is 0.5-0.6 m.

Earthworking capacity ranged from 270 to 810 m/h, depending on the dig depth and soil type. Maximum earthworking capacity is 1 200-1 400 m/h though in this case the trench will be only 0.4-0.5 m deep. Such trenches were made only if there was no time to dig out standard trenches. In this case soldiers would dig deeper on their own. Another use of these “fake” trenches was to mislead enemy intelligence.

The BTM-3 could dig straight, zigzag, or curved trenches. The rotor unloads the soil next to the trench, creating front and rear parapet of the trench which is around 0.5 m tall and provides additional protection.

Assembly: Kirov factory (Leningrad, USSR)

Year: 1956

Crew: 2

Speed of digging:

→ with a trench depth of 1.1 m 800 m³/h
→ with a trench depth of 1.5 m 560 m³/h

Max speed: 35 km/h

Weight: 26500 kg

Artillery Museum (Petrograd DistrictSt. Petersburg)

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