The T-54 and T-55 tanks are a series of main battle tanks (according to some sources) although not recognised medium tanks (the very concept of "main battle tanks" was applied only to tanks beginning with T-64A, armed with 125-mm tank gun) that were designed in the Soviet Union. The first T-54 prototype appeared in March 1945, just as the Second World War ended. The T-54 entered full production in 1947 and became the main tank for armored units of the Soviet Army, armies of the Warsaw Pact countries, and others. T-54s and T-55s were involved in many of the world's armed conflicts during the late 20th and early 21st century.
The T-54/55 series eventually became the most-produced tank in history. Estimated production numbers for the series range from 86,000 to 100,000. They were replaced by the T-62, T-64, T-72, T-80, and T-90 in the Soviet and Russian Armies, but remain in use by up to 50 other armies worldwide, some having received sophisticated retrofitting.
Soviet tanks never directly faced their NATO Cold War adversaries in Europe. However, the T-54/55's first appearance in the West in 1960 spurred the United States to develop the M60 Patton.
T-54
Production of the initial series of T-54s began slowly as 1,490 modifications were made. The Red Army received a tank that was superior to World War II designs and theoretically better than the newest tanks of potential opponents. The 100 mm gun fired BR-412 series full-calibre APHE ammunition, which had superior penetration capability compared to the T-34 that it replaced.
The serial production version, designated T-54-1, differed from the second T-54 prototype. It had thicker hull armour (80 mm on the sides, 30 mm on the roof and 20 mm on the bottom). As production ramped up, quality problems emerged. Production was stopped and an improved T-54-2 (Ob'yekt 137R) version was designed. Several changes were made and a new turret was fitted. The new dome-shaped turret with flat sides was inspired by the turret from the IS-3 heavy tank; it is similar to the later T-54 turret but with a distinctive overhang at the rear. It also had a shorter bustle. The fender machine guns were removed in favour of a single bow-mounted machine gun. The transmission was modernized and the track was widened to 580 mm. The T-54-2 entered production in 1949, at Stalin Ural Tank Factory No. 183 (Uralvagonzavod). In 1951, a second modernization was made, designated T-54-3 (Ob'yekt 137Sh), which had a new turret without side undercuts, as well as the new TSh-2-22 telescopic gunner's sight instead of the TSh-20. The tank featured the TDA smoke generating system. A command version was built, the T-54K (komandirskiy), with a second R-113 radio.
T-54A and T-54B
In the beginning of 1950s, the personnel of the OKB-520 design bureau of the Stalin Ural Tank Factory No. 183 (Uralvagonzavod) had been changed considerably. Morozov was replaced by Kolesnikow, who in turn was replaced by Leonid N. Kartsev in March 1953. The first decision of the new designer was to fit the 100 mm D-10T tank gun with the STP-1 "Gorizont" vertical stabilizer. The new tank gun received the designation D-10TG and was fitted into the T-54's turret. The new tank received night vision equipment for the driver and was designated T-54A (Ob'yekt 137G). Originally, this had a small muzzle counter-weight, which was later replaced with a fume extractor. It was equipped with an OPVT wading snorkel, the TSh-2A-22 telescopic sight, TVN-1 infrared driver's periscope and IR headlight, a new R-113 radio, multi-stage engine air filter and radiator controls for improved engine performance, an electrical oil pump, a bilge pump, an automatic fire extinguisher and extra fuel tanks. The tank officially entered production in 1954 and service in 1955. It served as a basis for T-54AK command tank, with additional R-112 radio set (front line tanks were equipped with R-113 radio set), TNA-2 navigational device, ammunition load for the main gun decreased by 5 rounds and the AB-1-P/30 charging unit, which was produced in small numbers. In October 1954 a T-54A tank, designated as T-54M (Ob'yekt 139) served as a testbed for new D-54T and D-54TS 100 mm smoothbore guns and "Raduga" and "Molniya" stabilization systems, which were later used in the T-62. These were not completely successful, so further T-55 development continued to use the D-10 series guns. It was fitted with V-54-6 engine developing 581 hp (433 kW). It never went into production.
A new version, based on T-54A, designated T-54B (Ob'yekt 137G2), was designed in 1955. It was fitted with a new 100 mm D-10T2S tank gun with STP-2 "Tsyklon" 2-plane stabilizer. It entered production in 1957. During the last four months of production, the new tanks were equipped with an L-2 "Luna" infrared searchlight and TPN-1-22-11 IR gunner's sight, and OU-3 IR commander's searchlight. Modern APFSDS ammunition was developed, dramatically enhancing the penetrative performance of the gun to keep it competitive with NATO armor developments. T-54B served as the basis for T-54BK command tank which had exactly the same additional equipment as the T-54AK command tank.
T-55
Trials with nuclear weapons showed that a T-54 could survive a 2–15 kt nuclear charge at a range of more than 300 metres (980 ft) from the epicenter, but the crew only had a chance of surviving at 700 metres (2,300 ft). It was decided to create an NBC (nuclear, biological, and chemical) protection system which would start working 0.3 seconds after detecting gamma radiation.
The task of creating a basic PAZ (Protivoatomnaya Zashchita) NBC protection system offering protection against the blast of a nuclear explosion and (radioactive) particulate filtration, but not against external gamma radiation or gas, was given to the KB-60 design bureau in Kharkov and was completed in 1956. The documentation was sent to Uralvagonzavod. It was decided to increase the tank's battle capabilities by changing the tank's construction and introducing new production technologies. Many of those changes were initially tested on the T-54M (Ob'yekt 139). The tank was fitted with the new V-55 12-cylinder 4-stroke one-chamber 38.88 litre water-cooled diesel engine developing 581 hp (433 kW). Greater engine power was accomplished by increasing the pressure of the fuel delivery and charging degree. The designers planned to introduce a heating system for the engine compartment and MC-1 diesel fuel filter. The engine was to be started pneumatically with the use of an AK-150S charger and an electric starter. This eliminated the need for the tank to carry a tank filled with air. To allow easier access during maintenance and repairs, it was decided to change hatches over the engine compartment. To increase the operational range, 300 litres (66 imp gal; 79 US gal) fuel tanks were added to the front of the hull, increasing the overall fuel capacity to 680 litres (150 imp gal; 180 US gal).
The ammunition load for the main gun was increased from 34 to 45, with 18 shells stored in so called "wet containers" located in hull fuel tanks (the concept for which came from Kartsev's cancelled Ob'yekt 140. The ammunition load included high explosive-fragmentation and anti-tank rounds and designers also planned to introduce the BK5M HEAT rounds which penetrated 390 millimetres (15 in) thick armour. The TPKU commander's vision device was replaced by either the TPKUB or TPKU-2B. The gunner received a TNP-165 vision device. The loader's hatch-mounted 12.7 mm DShK anti-aircraft heavy machine gun was dropped, because it was deemed worthless against high-performance jets. The tank was supposed to be equipped with the "Rosa" fire protection system. The tank had a thicker turret casting and the improved two-plane gun stabilization system from the T-54B, as well as night vision fighting equipment. To balance the weight of the new equipment, the armour on the back of the hull was thinned slightly.
The T-55 was significantly superior to the IS-2 Heavy Tank in all respects, including the rate of fire of the gun (at least four compared to less than three rounds per minute). Despite somewhat thinner frontal turret armour (200 millimetres (7.9 in) instead of 250 millimetres (9.8 in)) it compared favourably with the IS-3, thanks to its improved antitank gun and better mobility. Heavy tanks soon fell from favour, with only 350 IS-3s produced. The old model of highly mobile medium tanks and heavily armoured heavy tanks was replaced by a new paradigm: the "main battle tank". Parallel developments in the West would produce similar results. Katsev combined all the ongoing improvements being offered, or planned, on the T-54 into one design. This became the Ob'yect 155, and entered production at Uralvagonzavod 1 January 1958 as the T-55. It was accepted for service with the Red Army on 8 May. It suffered a significant lapse in one area: there was no antiaircraft machinegun, which had been present on the T-54.
After 1959, it served as a basis for the T-55K command tank which was equipped with an additional R-112 radio set, an AB-1-P/30 fuel powered accumulator charging unit, and TPN-1-22-11 night vision sight. All this additional equipment made it necessary to decrease the ammunition load for the main gun to 37 rounds and eliminate the bow machine gun. In the beginning of the 1960s, a T-55K was experimentally fitted with a Uran TV relay apparatus for battlefield surveillance. The tank was fitted with an external camera, the picture from which was relayed to a receiver in a BTR-50PU command vehicle. There was an observation camera mounted on a folding mast which was in turn mounted on a UAZ 69 car. The range within which the picture could be relayed varied between 10 and 30 kilometres (6.2 and 19 mi).
In 1961, a T-55 tank was used to test the "Almaz" TV complex which was supposed to replace the standard observation devices right after a nuclear explosion or while fording a body of water. There was a camera mounted on the hull for the driver and two cameras mounted on the turret, one for aiming and one for observation, and the picture from the cameras was relayed to two control screens. The tank had the front hull fuel tanks and bow machine gun removed. The commander was seated in the driver's usual position while the driver sat next to him. The cameras allowed battlefield observation and firing during daytime at ranges between 1.5 and 2 kilometres (0.93 and 1.2 mi). Because of the low quality of the equipment, the trials gave negative results. In the beginning of the 1960s, the OKB-29 design bureau in Omsk was working on adapting the tank to use a GTD-3T gas turbine engine developing 700 hp (522 kW). One T-55 tank fitted with this gas turbine engine passed trials but was deemed unsatisfactory and the design did not go into production.
The Omsk OKB-29 group tested three experimental T-55 tanks (designated Ob'yekt 612) between 1962 and 1965 that were fitted with an automatic gearbox controlled by electro-hydraulic systems. The trials found that such gearboxes were prone to frequent breakdowns in tanks. At the same time the Ob'yekt 155ML, a T-55 fitted with a launcher for three 9M14 "Malyutka" (NATO code: AT-3 Sagger) ATGMs mounted on the rear of the turret, was tested. Along with standard tanks a flamethrower-armed version was designed (designated TO-55 (Ob'yekt 482)), which was produced until 1962. It was fitted with 460 litre tanks filled with flammable liquid instead of the frontal hull fuel tanks. The flamethrower replaced the coaxial machine gun. This was a much better way to mount a flamethrower than in the experimental Ob'yekt 483, based on the T-54 tank, where the flamethrower replaced the main gun. TO-55 flamethrower tanks were withdrawn from service in 1993.
During the 1950s, the T-55 remained a significantly smaller and lighter tank than its NATO contemporaries—the U.S. M48 Patton and the British Centurion—while maintaining good firepower and reliability but light armor. The 100-mm D-10T tank gun had a larger bore than its Western counterparts.
In January 1945, some captured German tanks and vehicles were shipped to the Ordnance Research and Development Center, Aberdeen, Maryland, for tests and examination. The criteria for penetration in the tests was for at least fifty percent of the mass of the projectile to penetrate the armor. The M3 90 mm gun, firing the most widely equipped T33 armor-piercing round penetrated roughly 6 inches (150 mm) of steel armor at 100 metres (330 ft), while the T30E16 HVAP round penetrated 10.5 inches (270 mm) at the same range. These tests were carried out before the T-54/55 tank entered production, so it was not known how the popular 90 mm gun on the M46, M47, M48 and other western tanks would perform against the armour of the post-World War II Soviet tanks.
The data shows that the T33 AP round would fail to penetrate the frontal armour of the T-54/55 at any range, while the T30E16 HVAP round would only be able to penetrate the armour within 700 metres (2,300 ft). The T33 round could penetrate the side armour of the turret at about 800 metres, while the T30E16 HVAP round could do this at any practical range.The most popular anti-armor round the Soviets used for the D-10 tank gun was the 100 mm BR-412 APHE, first used on the SU-100 tank destroyer during World War II with an 80% probability of penetrating 135 millimetres (5.3 in) of steel armour at 1,000 metres (3,300 ft) fired from the D-10S tank gun. The BR-412D and BR-412B rounds developed in 1946–1950 had slightly superior performance over the 90 mm T33 and the M82 armor-piercing rounds.
This disadvantage lasted until the Soviet tanks began to be surpassed by newer Western developments like the M60 Main Battle Tank and upgraded Centurions and M48 Pattons using the 105 mm rifled Royal Ordnance L7 gun. Due to the low velocity of rounds from the 100 mm gun, and the tank's simple fire-control system, the T-54/55 was forced to rely on HEAT shaped-charge ammunition to engage tanks at long range well into the 1960s, despite the relative inaccuracy of this ammunition at long ranges. The Soviets considered this acceptable for a potential European conflict, until the development of composite armor began reducing the effectiveness of HEAT warheads and sabot rounds were developed for the D-10T gun.
| Specifications (T-55) | |
|---|---|
| Weight | 36 tonnes (39.7 ST) |
| Length | 6.45 m |
| Width | 3.37 m |
| Height | 2.40 m |
| Crew | 4 |
| Armour | hull front 100 mm @60°, turret front 205 mm (rounded), hull side 80 mm @0°, lower hull side 20 mm @0°, turret side 130 mm (rounded), hull rear 60 mm @0°, turret rear 60 mm (rounded), hull top 33-16 mm, turret top 30 mm, hull floor 20 mm |
Main
armament | D-10T 100 mm rifled gun |
Secondary
armament | 7.62 mm SGMT coaxial machine gun, (12.7 mm DShK heavy machine gun) |
| Engine | Model V-55(V-54) V-12 water-cooled. 38.88-l diesel 581 hp (433 kW) |
| Power/weight | 14.6 hp/tonne |
| Transmission | Mechanical synchromesh, 5 forward, 1 reverse gears |
| Suspension | Torsion bar |
| Ground clearance | 0.425 m |
| Fuel capacity | 580 l internal, 320 l external (less on early T54), 400 l jettisonable rear drums |
| Speed | 48 km/h (30 mph) |
Source : Wikipedia
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