The PT-76 (Plavayushchiy Tank 76 or Amphibious Tank 76) is notably one of the most famous amphibious light tank from Soviet era. Around 2 000 units of these tanks were exported around the globe. Despite being a product from 1950s, the tank is still in service with many countries. Currently there are 25 countries using the PT-76 of many variants, mostly upgraded to extend the tanks’ service life.

   The PT-76 also became the mainstay in Indonesian Marine Corps, along with the BTR-50s. Both of these armored vehicles were acquired from Soviet Union in 1962 to support military operations at the time. Around 170 units were actively used during its service peak with the Indonesian Marines. However, a bloody revolt led by Indonesian Communist Party in 1965, which failed and ultimately led to its disbandment and eradication by Indonesian Army. Due to this incident Soviet Union imposed an arms embargo on Indonesia which lasted until the collapse of the Soviet Union in 1991. The embargo brought disastrous impact on the Indonesian military which at the time was mostly comprised of Soviet weapons. This inevitably led to the significant decrease of operational PT-76Bs and BTR-50s, along with many other Soviet-made armored vehicles. Some vehicles were cannibalization for parts in order to keep other vehicles operational.

   Currently there are around 120 units of PT-76s in service with Indonesia. Some of these amphibious tanks were retrofitted with an upgrade package offered by Nimda of Israel, albeit exact numbers are unknown. The upgraded PT-76s are designated as PT-76(M) (not to be confused with Soviet PT-76M variant). The retrofit program started in early 1990s, and several upgraded PT-76(M) tanks joined in a counterinsurgency campaign in the early 2000s against Free Aceh Movement (GAM). Recently, Indonesian company PT Lumindo Artha Sejati was contracted to continue the upgrades with same package and overhauls in order to keep the tanks in combat-ready condition. The newly upgraded and overhauled PT-76 is referred to as the PT-76(M) by the company, although some sources refer to it as the PT-76P. The upgrade package included engine, fire suppression system, new alternator, new cooling and electrical system, along with weapon system replacements, as the old systems were deemed extremely outdated.

   In the upgrade package, PT-76B's original V-6 diesel engine is replaced with newer and more powerful Detroit Diesel 6V-92T engine. This new engine is capable of generating 300 hp, coupled with the original transmission. Maximum speed of PT-76(M) with the new engine is 58 km/h on road and 40 km/h off road. On water, these tanks can move at 9 km/h, propelled by 2 water jets located on the rear. The 76.2 mm rifled D-56T gun is replaced by a 90 mm Cockerill Mk.3M-A2 gun along with new fire control system. This new main gun is capable of firing a wide range of munitions, including APFSDS, HEAT, HESH, HE, and canister rounds. PT-76’s original DShK 7.62 mm coaxial machine gun is replaced with an FN MAG 7.62x51mm general purpose machine gun. The new fire control system includes a new day/night sight and a laser range-finder. It significantly increased the tanks' combat capabilities, as the original PT-76B's was greatly limited during night operations. In addition, upgraded tanks are fitted with a new solid-state all-electric gun/turret stabilization and power control system, increasing accuracy when firing on the move.

   Recently, in December 2020 newer information and details were released, confirming that first batch of 40 PT-76s will receive further upgrades from Ukraine through Ukrainian state-owned company Ukrspetsexport, while the upgrades will be executed together with PT Lumindo Artha Sejati. These upgrades include installation of Zaslon-L active protection system, Cummins VT-400 diesel engine, Synthesis fire control system, Basalt navigation system, newer radio from Harris, as well as AVZK communication system and 4 additional shock absorbers for better suspension. The original tank control levers will be also replaced with a steering wheel, thus improving ergonomics for the crew.

   Interestingly, these upgrades also include purchase of 9 90 anti-tank guided missiles, which can be fired in the same fashion as regular ammunitions from the new main gun. This enables the tank to effectively engage hostile tanks, armored vehicles, building and even helicopters at a maximum range of 4 km.  Indonesia also employs Falarick 105, which can be fired by the Kaplan / Harimau Hitam.

   It is noted that further details on the upgrades including the exact number of upgraded units have not been released, as it is still ongoing. However, it is clear that these upgrades are part of interim measures before the government decides on proper replacements for the PT-76s. There is also a possibility that Ukraine will upgrade remaining operational PT-76s, if the Ministry of Defense deems the upgrade results of the first batch satisfactory. In 2018 the Indonesian Navy reportedly showed interest on Russian Sprut-SDM1 amphibious light tank, though the details on whether the government will proceed with the purchase is still unknown, as they had recently acquired Russian BMP-3F infantry fighting vehicles instead for the marines. On the other hand, PT Pindad and FNSS of Turkey, both of which jointly developed Kaplan / Harimau Hitam medium tank, are reportedly in talks to possibly develop an amphibious tank which will apparently replace the ageing PT-76s. Following these recent upgrades, Ukraine is also offering its amphibious vehicles to Indonesia including BTR-4, pursuing new possibilities of joint production, as well as actively proposing upgrades for older Soviet-era vehicles.

Article by ANINDYA GALIH WIBISONO    Want to publish your own articles? Visit our guidelines for more information.