PT-76 амфибиялық жеңіл танкының сипаттамасы

Amphibious light tank
A prototype was built at Kirov Plant in 1950 and the tank was officially adopted on 6 August 1951 with the designation PT 76. Production started at the Stalingrad Tractor Factory (STZ). The tank was subsequently modified. In 1957, the D 56T gun was replaced with the D 56TM with double baffle muzzle brake and fume extractor and the hull was raised by 13 cm, additionally the tank was equipped with new vision and communications devices.

The PT 76 has a typical tank layout: the steering compartment at the front, the combat compartment in the center and the engine compartment at the back. The tank has a three man crew, with the commander also acting as the radio operator and gunner. This reduces his effectiveness as an observer. The commander and loader stations are located inside the turret, the commander sits on the left side of the main gun and the loader sits on the right. They have a large oval shaped double hatch, which opens forwards on top of the turret. The driver sits in the center of the front of the hull and has a one piece hatch that opens to the right, with three vision blocks and periscopes located beneath the main gun at the top of the sloping glacis plate. Under the driver's seat, there is an emergency hatch that can be used by all crew members. At night, the center periscope is swapped for a TVN 2B night vision device which gives the driver clear vision up to 60 meters.

Its main armament consists of a 76.2 mm D 56T series rifled tank gun, which has an effective range of approximately 1,500 meters and a rate of fire of six to eight rounds per minute. This gun is 42 calibers long. The PT 76 carries 40 rounds for its gun. A typical ammunition load consists of 24 x OF 350 Frag HE, 4 x AP T, 4 x API T and 8 x BK 350M HEAT rounds (with AP T rounds substituted for HVAP when available). The gun is mounted in an oval dish type circular truncated cone turret with flat, sloping sides which is mounted over the second, third, and fourth pair of road wheels. All PT 76s have a fume extractor for the main gun at the rear of the turret.

The torsion bar suspension consists of six evenly spaced large rubber tired road wheels with the drive sprocket at the rear and the idler at the front. The road wheels are hollow to minimize weight. These hollow road wheels increase the tank's buoyancy by 30%. There are no track return rollers. The first and last road wheels have a hydraulic shock absorber and the steel tracks have 96 links each when new, each link has a single pin. There is a small, thin, horizontal skirt over each track. Its straight 6 cylinder, 4 stroke water cooled diesel engine was developed under the designation "V 6" by halving the "V 12" engine from the T 54/55. It develops 240 hp (179 kW) at 1,800 rpm which gives it a road speed of 44 km/h and a range of 370 km to 400 km. The vehicle can cross 1.1 m high vertical obstacles and 2.8 m wide trenches and climb 52° gradients. The engine has a cooling system and an initial heater (intended for use when the air temperature is −20 °C or colder). The PT 76 has a 5 speed manual shaft type transmission system similar to the one in the T 34/85. The gearbox has four forward gears and one reverse. The vehicle has a side clutch that enables it to make turns and a handbrake. The tank has four mounts for additional external fuel tanks at the rear of the hull. The two on the corners are for flat type external tanks and the two in the center are for a drum type. These additional tanks increase the range from 370 to 400 km to 480–510 km. The PT 76 is a reliable, simple to operate and highly mobile reconnaissance vehicle and is ideally designed for amphibious operations, but it has many limitations as a fighting vehicle.

The PT 76 is amphibious, it has a flat, boat shaped hull which is hermetical and ensures minimal resistance when the tank is afloat. It can swim after switching on the two electric bilge pumps, erecting the trim vane which improves the vehicle's stability and displacement in the water and prevents water from flooding into the bow of the tank. Switching the driver's periscope for a swimming periscope enables the driver to see over the trim vane. When not in use the trim vane is stowed in the front of the bow under the barrel of the main gun and serves as additional armor. Bilge pumps keep the tank afloat even if it leaks or is damaged. There is a manual bilge pump for emergency use. The tank is propelled through the water by two hydrojets, one on each side of the hull, with the inlets underneath the hull and the outlets at the rear. There are also additional assistant water jet inlets on both sides of the hull over the last road wheels. The rear outlets have lids that can be fully or partially closed, redirecting the water stream to the forward directed outlets at the sides of the hull, thus enabling the vehicle to turn or go in reverse. To turn to the left for example, the left water jet is covered, to turn to the right, the right water jet is covered. To make a 180° turn, one water jet sucks in water while the other pushes it out. This system was designed by N. Konowalow. It is the same system as the one used in the BTR 50 APC, which was based on the PT 76. The tank can swim at up to 10.2 km/h and has a range of 100 km. It can cross most water obstacles and can also swim in the sea. However, its amphibious design makes it disproportionally large for a vehicle of its weight and allows less armor protection than other light tanks. The main disadvantage of the BMP 1 and the BRM 1 when compared to the PT 76 is the absence of a powerful main armament. However, the BRM 1 is fitted with more modern reconnaissance equipment. Also, both vehicles have stronger front armor and superior mobility features and the BMP 1 can carry up to 8 fully equipped soldiers inside. The PT 76 is still on active service in a number of countries mainly in the developing world. The Russian Army is reported to have used PT 76 units in the war in Chechnya. The PT 76 is used/stationed by/in following Russian units/bases: 61st tank repair plant (1), 61st Kirkinesskaya marine brigade (26) from Sputnik, which is part of the Murmansk military district, 175th marine brigade (26) from Tumannyy, which is part of the Murmansk military district and 336th Belostokskaya marine brigade (26) from Baltyysk, which is part of the Kaliningrad military district. In Ludowe Wojsko Polskie (LWP), PT 76s and PT 76Bs were used by the reconnaissance subunits of tank divisions and mechanized divisions and Coastal Defense units including the 7th Lusatian Landing Division (officially known as 7th Coast Defense Division). PT 76s were in service with the Indian Army and they were in reserve status before they were withdrawn from service in 2009, after which they were used for target practice by the army and as static memorials at various military facilities. (they had already been used in the preceding Battle of Ban Houei Sane, which was just across the border in Laos however). Thirteen PT 76s, of the PAVN 202nd Armored Regiment spearheaded an assault against approximately 24 Green Berets, 500 South Vietnamese irregulars and 350 Laotian Royal soldiers. The defenders fought back with their 106 mm M40 recoilless rifle (one at the entrance took out three PT 76s until it was knocked out), and ineffectively with M72 LAWs (one shot disposable 66 mm Light Anti Tank Weapon). They requested support from nearby Khe Sanh Combat Base, which was unable to help, as it too was under siege.]] The Battle of Ben Het was the only PAVN–US Army tank battle during the course of the Vietnam War. 10 PT 76s faced 3 M48s. On March 3, 1969, the Special Forces' Ben Het Camp was attacked by the PAVN 202nd Armored Regiment. The 202nd was given the task of destroying the camp's 175 mm self propelled guns. One of the PT 76s had detonated a land mine, which not only alerted the camp, but also lit up the other PT 76s attacking the firebase. Flares had been sent up, thus exposing adversary tanks, but sighting in on muzzle flashes, one PT 76 scored a direct hit on the turret of a M48, killing two crewmen and wounding two more. A second M48, using the same technique, destroyed a PT 76 with their second shot. At daybreak, the battlefield revealed the wreckage of two PT 76s and one BTR 50 armored personnel carrier. On April 24, 1972, the US special experimental 1st Combat Aerial TOW Team arrived in South Vietnam. It consisted of two UH 1B helicopters mounting the new BGM 71 TOW and technicians from Bell Helicopters and Hughes Aircraft Corporation. It deployed in the Central Highlands, where it commenced gunnery training. From May 2, the team made daily flights in search of enemy armor, with the missiles mounted in the XM26 three tube launcher. On May 9, PAVN armored units attacked Ben Het Camp; the TOW team destroyed 3 PT 76s and broke up the attack. On May 26, the PAVN made another attempt to retake the city of Kontum. TOW aircraft were brought in at first light and found PAVN tanks moving almost at will through portions of the city. Conventional air strikes would have been risky for friendly forces, and the TOW proved to be ideal for picking off enemy tanks. At the end of the first day, the two TOW helicopters had destroyed 9 tanks and damaged one more. Four destroyed and one damaged were PT 76s.

The PT 76 saw action with Indian forces in the Indo Pakistani War of 1965 and 1971. The superior tactics of the Indian Army enabled the PT 76 to play a vital role in the Eastern theater of the 1971 war where the PT 76s proved superior to the obsolete Pakistani M24 Chaffee light tanks despite being outnumbered. A good example of such an engagement was the Battle of Garibpur, where an Indian Army Infantry Battalion with only 14 PT 76s was able to maul a much larger brigade strength unit of Pakistani armor and inflict heavy casualties. During the battle 8 Pakistani M24 Chaffee tanks were destroyed, 3 captured at the cost of 2 PT 76.

The PT 76 also saw service in the Six Day War (1967) during which the Israeli army destroyed or captured a few PT 76 tanks. During the Yom Kippur War in 1973 PT 76s were used during the crossing of the Great Bitter Lake by the Egyptian 130th Marines Brigade. The People's Armed Forces of Liberation of Angola (FAPLA) deployed PT 76s during the Angolan Civil War, as did Cuba during its lengthy military intervention in that country. One FAPLA PT 76 was destroyed by a South African Ratel 90 armoured car during Operation Moduler. At least six others were captured by South African expeditionary forces over the course of that conflict. During the Yugoslav wars, the PT 76 served with the Yugoslav People's Army and later the army of the Krajina Serbs in a few battles during the Ten Day War in Slovenia (1991) and Croatian War of Independence (1991–1995). The Indonesian Marine Corps used its PT 76Bs on the Indonesian island of Ambon during Maluku sectarian conflict in 1999 2003, and also in mid 1970s during Operation Lotus (Operasi Seroja).

PT 76M – An upgraded PT 76 with a UTD 20 engine developing 300 hp (224 kW), new steering and brake systems, designed by Minotor Service in Minsk. A similar upgrade exists for the BTR 50 series.

– The Chinese obtained a few PT 76s in the mid 1950s. In October 1958, the People's Liberation Army (PLA), decided to develop an indigenous amphibious tank based on the PT 76. The development program was carried out by 201 Institute and 615 Factory. A prototype known as the WZ221 was built and tested in 1959, but the design suffered from a number of problems including engine overheating. The PLA was not satisfied with the performance of the vehicle, which led to the development of a new vehicle based on the Type 60, Type 63 amphibious light tank.

OT 62 TOPAS (OT 62 stands for Obrněný Transportér vzor 62 – "Armored Personnel Carrier model 62") ("TOPAS" stands for Transportér Obrněný PÁSový – "Tracked Armored Personnel Carrier") – A series of BTR 50 variants developed jointly by Poland and Czechoslovakia. They are similar to the BTR 50PK but have hatches in the hull sides, a more powerful PV 6 engine of 300 hp (224 kW) and two projecting bays like the BTR 50PU.

– Command tank based on PT 76 Model 2s and PT 76Bs. It is equipped with an extra R 112 radio.

PT 76(M) – Indonesian Marines PT 76B modernized with PT 2000 upgrade package from Nimda, Israel in 1990s. Fitted with Cockerill Mk 3M A2 90 mm gun (with multi slot muzzle brake), FN MAG as coaxial and pintle mounted machine guns, a larger gunners sight and a new Detroit Diesel 6V92T engine. PT 76(M) – PT 76 used by the Indonesian Marines were upgraded by PT Lumindo Artha Sejati in May 2020. New Detroit Diesel 6V92T engine with 300 hp, Cockerill Mk 3M A2 90 mm gun (with multi slot muzzle brake), new fire control system, new day/night sight, a laser rangefinder, and new gun stabilizer. PT 76(M) with LCTS 90 – Proposed upgrades by Ukrspetsexport in collaboration with PT Lumindo Artha Sejati in mid 2020. The original turret were replaced with John Cockerill LCTS 90MP turret, armed with Cockerill Mk 3M A2 90 mm gun and equipped with autoloader. The upgrades also includes ability to launch Falarick 90 ATGM, new Cummins VT400 diesel engine and Allison transmission, installation of "Zaslon L" active protection system, "Sintez" fire control system, "Bazalt" navigation system, Harris radios and other improvements. TAPIR (Tank Amphibi Peluncur Incendiary Rocket – "Amphibious Incendiary Rocket Launcher Tank") – One PT 76B was modified with the 17 tube 140 mm rocket launcher of the BM 14 17 installed on top of the turret and with the main gun removed. Modified by PT Also Putra Indonesia in 1995. The project was discontinued due to inadequate funding.

(Not to be confused with the Soviet PT 71) – Is a PT 76 upgrade built by Nimda Group Ltd., which includes a 90 mm Cockerill tank gun, a new machine gun, a new fire control system, a laser range finder, night vision devices and a 300 hp (224 kW) Detroit Diesel 6V71T diesel engine. The only known customers were the Israeli and Indonesian armies. It was developed by CB Burevestnik (Nizhniy Novgorod). Its armor piercing tracer rounds fired from 1,120 m can penetrate 100 mm of steel armor. The new weapon can destroy most modern APCs and IFVs. It can also engage aerial targets out to 6 km. The autocannon uses two types of ammunition, splinter tracer and armor piercing tracer. However, it is possible to fire a special zenith shell. The gun can fire single shots, short bursts (2 to 5 rounds), or long bursts (up to 20 rounds). It can also fire continuously up to 120 rounds per minute. This system functions by using the energy generated by each round, not by using an external power source. Firepower is improved 5.5 times in the PT 76E over the PT 76B. The PT 76E is fitted with a more powerful UTD 20 6 cylinder 4 stroke V shaped airless injection water cooled multifuel 15.8 litre diesel engine. It develops 300 hp (224 kW) at 2,600 rpm and is taken from the BMP 1 as is the transmission. The power to weight ratio has been improved to per ton. This also increases the maximum road speed from 44 km/h to 60 km/h, with an average cross country speed from 32 km/h to 42 km/h. Other engine options are the UTD 23 or V 6BF. The vehicle has new tracks. Driver fatigue has been reduced. The vehicle's survivability on the battlefield is improved with the introduction of a new fast acting firefighting system. The vehicle also has improvements in fire control and optical equipment, for instance the new sights 1P67 and "Liga S". This modernization program increases the PT 76's performance by 2.7 times, which is still comparatively low. The vehicle was accepted by the Russian marines in 2006 and about 40 or 50 vehicles were ordered.