Vietnamese army has upgraded Soviet-made PTS-M, a tracked amphibious vehicle especially designed for river crossing operations. The vehicle is able to transport military equipment or personnel with a payload capacity of 10,000 kg on water. The upgraded version of the Vietnamese army is fitted with ZU-23-2 anti-aircraft twin-cannon.

Vietnamese army PTS-M amphibious tracked vehicle armed with ZU-23-2 anti-aircraft cannon at military parade in Vietnam. (Picture source BaoDatViet)

The PTS-M tracked amphibious vehicle first appeared in 1969, it's a modified version of the PTS. The two vehicles are based on the elongated chassis of the Soviet-made ATS-59 tracked artillery tractor. The crew compartment is at the front of the vehicle and is fully sealed against NBC attack. The crew enter the cab via two circular hatches in the roof.

There is a large cargo area at the rear of the vehicle, for the Vietnamese army version, the ZU-23-2 is carried immediately at the rear of the crew compartment in the cargo area.

In the water, the PTS-M is propelled in the water at a maximum speed of 12 km/h by two propellers in tunnels under the rear of the hull and steering is by two rudders at the rear of the hull.

The ZU-23-2 also known as ZU-23, is a Russian-made towed 23 mm anti-aircraft twin-barreled automatic cannon. It was designed to engage low-flying targets at a range of 2.5 km as well as armoured vehicles at a range of 2 km and for direct defense of troops and strategic locations against air assault usually conducted by helicopters and low-flying airplanes.

The ZU-23-2 is armed with two 2A14 23 mm auto-cannons on a small trailer which can be converted into a stationary mount for firing the guns. Two types of fixed ammunitions are fired by the ZU-23-2, namely armour-piercing-incendiary-tracer (API-T) and high-explosive incendiary-tracer (HEI-T).