Russian Light Tank T-46 (Tier III)

The T-46 Light Tank was developed in an attempt to improve the mobility of the T-26, the most numerous Soviet tank from the mid-1930s until the German invasion of 1941. The T-26 suspension consisted of eight small road wheels carried in pairs on small bogies. The bogies were supported in pairs by leaf springs. This was less effective than the Christie suspension used on the BT series of fast tanks, and so in 1935, S. Ginzburg of the OKMO team at Zavod No.185 was ordered to produce a new version of the T-26 using the Christie suspension. A small production run of seventy tanks was planned.

The project was abandoned after the production of a number of prototypes (or possibly of all seventy tanks from the first production run). The T-46 proved to be too complex to mass produce (a flaw that would also cause the failure of the T-25). It also offered little or no benefit over the BT series tanks. Ginzburg and his team were ordered to concentrate on improving the design of the T-26, and produced the T-26S Model 1937.

One brigade is known to have used some of the existing T-46s during the fighting in Finland in 1940, where the Red Army suffered a humiliating setback. A few T-46 prototypes were deployed in October 1941 as one of the desperate measures to stop the German advance to Moscow. Although it is not clear weather these T-46s ever engaged in actual combat, they were used in a static defense line. With wheels and tracks removed and buried into the ground, emerging turrets had the role of a static pilebox.

Type	Light infantry tank
Place of origin	Soviet Union
Service history
Used by	Soviet Union
Wars	World War II
Production history
Designer	S. Ginzburg, L. Troyanov, OKMO
Designed	1939–41
Manufacturer	Factory 174, Omsk
Produced	1941–42
Number built	69
Specifications ([1])
Weight	14 tonnes
Length	5.20 m (17 ft 1 in)
Width	2.47 m (8 ft 1 in)
Height	2.16 m (7 ft 1 in)
Crew	4
Armor	12–37 mm
Main armament	45 mm Model 1938 gun (150 rds.)
Secondary armament	7.62 mm DT machine gun
Engine	diesel model V-4 300 hp (220 kW)
Power/weight	21 hp/tonne
Suspension	torsion bar
Fuel capacity	350 l
Operational range	220 km
Speed	60 km/h (37 mph)

Historical Gallery

Russian Light Tank BT-7(Tier III)

The BT tanks (Russian: Быстроходный танк (БТ), Bystrokhodny tank, lit. "fast tank" or "high-speed tank"^[1]) were a series of Soviet cavalry tanksproduced in large numbers between 1932 and 1941. They were lightly armoured, but reasonably well-armed for their time, and had the best mobility of all contemporary tanks of the world. The BT tanks were known by the nickname Betka from the acronym, or its diminutive Betushka.^[2]

The direct successor of the BT tanks would be the famous T-34 medium tank, introduced in 1940, which would replace all of the Soviet fast tanks, infantry tanks, and medium tanks in service.

BT-2, BT-5, BT-7, BT-7M
BT-5
Type	Light cavalry tank
Place of origin	Soviet Union
Service history
In service	1932–45
Wars	Spanish Civil War, Soviet–Japanese border conflicts, Winter War. World War II
Production history
Designer	J. Walter Christie, Morozov
Designed	1930–31
Manufacturer	KhPZ
Produced	1932–41
Number built	BT-2: 650 BT-5: 1884 BT-7: 5556
Variants	BT-2, BT-5, BT-7, BT-7M
Specifications (BT-5)
Weight	11.5 tonnes (12.676 tons)
Length	5.58 m (18 ft 4 in)
Width	2.23 m (7 ft 4 in)
Height	2.25 m (7 ft 5 in)
Crew	3
Armour	6–13 mm
Main armament	45-mm Model 32 tank gun
Secondary armament	7.62-mm DT machine gun
Engine	Model M-5 400 hp (298 kW)
Power/weight	35 hp/tonne
Suspension	Christie
Fuel capacity	360 litres (95 US gal)
Operational range	200 km (120 mi)
Speed	72 km/h (44.7 mph)

Design

The BT tanks were "convertible tanks". This was a feature designed by J. Walter Christie to reduce wear of the unreliable tank tracks of the 1930s. In about thirty minutes the crew could remove the tracks and engage a chain drive to the rearmost road wheel on each side, allowing the tank to travel at very high speeds on roads. In wheeled mode the tank was steered by pivoting the front road wheels. However, Soviet tank forces soon found the convertible option of little practical use in a country with few paved roads, and it consumed space and added needless complexity and weight. The feature was dropped from later Soviet designs.

Christie, a race car mechanic^{[citation needed]} from New Jersey, had tried unsuccessfully to convince the U.S. Army Ordnance Bureau to adopt hisChristie tank design. In 1930, Soviet agents at Amtorg, ostensibly a Soviet trade organization, used their New York political contacts to persuade U.S. military and civilian officials to provide plans and specifications of the Christie tank to the Soviet Union. At least two of Christie's M1931 tanks (withoutturrets) were later purchased in the United States and sent to the Soviet Union under false documentation in which they were described as "agricultural tractors."^{[citation needed]} Both tanks were successfully delivered to the Kharkov Komintern Locomotive Plant (KhPZ). The original Christie tanks were designated fast tanks by the Soviets, abbreviated BT (later referred to as BT-1). Based both on them and on previously obtained plans, three unarmed BT-2 prototypes were completed in October 1931 and mass production began in 1932. Most BT-2s were equipped with a 37 mm gun and a machine gun, but shortages of 37 mm guns led to some early examples being fitted with three machine guns.

The sloping front hull (glacis plate) armor design of the Christie M1931 prototype was retained in later Soviet tank hull designs, later adopted for side armor as well.

The BT-5 and later models were equipped with a 45 mm gun.

Russian Light Tank Tetrarch (Tier II)

The Light Tank Mk VII (A17), also known as the Tetrarch, was a British light tank produced by Vickers-Armstrong in the late 1930s and deployed during theSecond World War. The Tetrarch was originally designed as the latest in the line of light tanks built by the company for the British Army. It improved upon its predecessor, the Mk VIB Light Tank, by introducing the extra firepower of a2 pounder gun. The War Office ordered 70 tanks, an order that eventually increased to 220. Production was delayed by several factors, and as a consequence, only 100 to 177 of the tanks were produced.

The tank's design flaws, combined with the decision by the War Office not to use light tanks in British armoured divisions, ruled out the use of Tetrarchs in the North African campaign. As a result, the majority of the tanks remained in Britain, although 20 were sent to the USSR as part of the Lend-Lease program. In early 1941, the Royal Armoured Corps formed three squadrons for use in overseas amphibious operations; one of which was equipped with Tetrarchs. In May 1942, a small number of Tetrarchs formed part of the British force which participated in the invasion of Madagascar, and, in June 1942, Tetrarchs were attached to the 1st Airborne Division after it was decided that the design allowed its use as an air-portable light tank to support British airborne forces. The Tetrarchs were transported and landed in specially designed General Aircraft Hamilcar gliders.^[4] A lack of gliders prevented their participation in the Allied invasion of Sicily in 1943; instead they were attached to the new 6th Airborne Division and became part of the 6th Airborne Armoured Reconnaissance Regiment.

The division used approximately 20 Tetrarchs during the British airborne landings in Normandy in June 1944. The tanks were successfully landed by glider, but they did not perform well. Several were lost in accidents, and those that did see action proved to be inferior in firepower and armour to the armoured fighting vehicles of the German forces. A few days after the beginning of the operation, the tanks were removed from direct engagement with German armour and used only to provide fire support. By August 1944, most of the Tetrarchs in action were replaced with Cromwell cruiser tanks, and the remainder were replaced by the M22 Locust in December 1944.

Tetrarchs did not see any further combat and were deemed obsolete by 1946; the last was retired in 1950. There were several variations on the Tetrarch design, including the Alecto self-propelled gun and the Light Tank Mk VIII, but none of these were ever used in active service with the British Army.

Tank, Light Mk VII, Tetrarch
Mk VII Light Tank 'Tetrarch'
Type	Light tank
Place of origin	United Kingdom
Service history
Used by	United Kingdom  Soviet Union
Wars	Second World War
Production history
Designer	Vickers-Armstrong
Designed	1938
Manufacturer	Metro-Cammell
Produced	1938–1942[1]
Number built	100–177[2]
Variants	Tetrarch I CS, Tetrarch DD
Specifications
Weight	17,000 pounds (7,600 kg)
Length	13 ft 6 in (4.11 m)[3]
Width	7 ft 7 in (2.31 m)[1]
Height	6 ft 11 in (2.12 m)[1]
Crew	3[1] (Commander, gunner, driver)
Armour	14 mm
Main armament	QF 2 pounder (40 mm) 50 rounds
Secondary armament	7.92 mm Besa machine gun 2,025 rounds
Engine	Meadows 12-cylinder petrol 165 hp
Suspension	Coil spring
Operational range	140 miles (230 km)[1]
Speed	40 miles per hour (64 km/h),[1] off–road 28 miles per hour (45 km/h)

Development history

The prototype of the Light Tank Mk VII (A17), nicknamed 'Purdah',^[5] was first developed in 1937 by Vickers-Armstrong as a private venture, and was intended to be sold either to the British Army or to foreign militaries.^[6] It was to be the latest in a series of light tanksproduced by the company.^[6] The tank was designed to overcome the shortcomings of insufficient armament in earlier light tanks that were fitted only with machine guns.^[7] Vickers-Armstrong installed on the Mk VIIs a 2 pounder 40-millimetre (1.6 in) main gun paired with a 7.92-millimetre (0.312 in) Besa machine gun, and mounted the two guns in a two-man turret. The tank possessed a maximum of 14 millimetres (0.55 in) of armour.^[6][7] The prototype weighed approximately 17,000 pounds (7,600 kg) and was powered by a 165-horsepower (123 kW) Meadows engine. Suspension was on eight road wheels, four per side, with no separate driver or idler wheels and it was capable of a 40 miles per hour (64 km/h) top speed.^[5][8] The Mk VII design relied on an unusual steering method and a mechanical system incorporated into earlier Vickers models.^[9] The front wheels could be steered to allow for gentle turns by bending the tracks. For sharper turns, the system returned to the conventional method of braking one track to turn the tank; the dual system of turning was to designed to lessen mechanical strain on the MkVII and reduce its power wastage.^[1][7][10] The suspension system was also a new design that relied on struts with pockets of air for springing and cushions of oil for damping, and each of the wheels was independently sprung.^[10]

General Sir Alan Brooke, Commander-in-Chief Home Forces, inspecting a Light Tank Mk VII (Tetrarch) at the Army Staff College, 1941

The War Office examined the design and put the prototype through a series of trials during May and June 1938; the model was tested as a possible "light cruiser" since War Office light tank needs were already met by its predecessor, the Mark VI.^[9] The War Office then took the view that the tank was not acceptable as a light cruiser because the Nuffield A13 offered better speed and obstacle crossing performance.^[11] Despite this, it was decided that it was essential for some Tetrarchs to be produced, and it was suggested that they be brought in at the end of the light tank program.^[11] Accordingly, the War Office gave the Tetrarch the official General Staff specification number A17, and, in November 1938, accepted it for limited production after requesting a few minor changes which included the fitting of an external fuel tank to increase the tank's range.^[8] The number to be produced was subject to fluctuation as the War Office vacillated in their demand; in July 1938, it requested that 70 of the tanks be produced, then increased the request to 120 after a three-day conference in November. Production was to begin in July 1940, but meanwhile the War Office temporarily returned to its original order of 70 before increasing the number to 100. The number further increased to 220 after Metropolitan Cammell Carriage and Wagon, a company part owned by Vickers-Armstrong that would be producing the tanks, indicated it had already ordered armour plating for that many tanks.^[2][12]

Production of the tank was delayed by a number of factors. The War Office put their order on hold in a post-Battle of France decision to focus military production on infantry and cruiser tanks,^[13] due to the poor performance of British light tanks during that battle. Due to the shortage of more suitable tanks, light tanks that were not designed for use against German armour, were nevertheless deployed against them; the resulting high casualties led the War Office to re-evaluate the suitability of the light tank design.^[2] The pre-war role of the light tank, that of reconnaissance, meanwhile had been found to be better suited to scout cars that used smaller crews and had better cross-country abilities.^[2][5] Further delays were caused by the bombing raids of the Luftwaffe during May 1941 against the factories where the tanks were assembled.^[14] These delays resulted in the production of only a small number of Mk VIIs; estimates place the final total produced to be between 100 and 177.^{[Note 1]} The name 'Tetrarch' was given to the Mk VII, on 22 September 1941, on the orders of the War Office. The last of the tanks were built in the first quarter of 1942 and delivered at the end of the year.^[2]

The War Office and the Army were concluding, at this point, that light tanks were a liability and too vulnerable for use in further combat,^[5] and the Tetrarch was considered to be obsolete.^[15] This decision may have marked the end for the Tetrarch in active service; several of the tanks destined to be deployed to the Eighth Army in the Middle East for the North African Campaign were left in Britain when their cooling systems were determined to be unable to cope with the intense North African heat.^[16] However, the demise of Tetrarch was prevented by a decision made by the War Office in mid-1941, as it was considering the equipment to be used by Britain's fledgling airborne forces, formed in June 1940 under the orders of the Prime Minister, Winston Churchill.^[17] When selecting the equipment for the airborne forces, officials at the War Office concluded that gliders would be an integral component; gliders would transport troops and heavy equipment, which, by 1941, was to include artillery and some form of tank.^[18] Plans to transport a tank went through a number of revisions, but, by May 1941, the feasibility of a 5.5 metric tons (5.4 long tons) tank to be carried for 350 miles (560 km) in a glider was accepted, although the aircraft would have to be specifically designed for the task. In a conference held on 16 January 1941, it was decided that the General Aircraft Hamilcar, currently under development, would be used to transport a single Tetrarch tank or two Universal Carriers.^[13][19] The Tetrarch was chosen because it was an obsolete design, and was therefore available to be used by the airborne forces.^[15]

Beginning in January 1944, training exercises were conducted carrying the Tetrarchs and their crews inside Hamilcar gliders. These exercises were successful; during the training by 'C' Squadron of the Glider Pilot Regiment, which specialised in flying the Hamilcars, over 2,800 lifts were made with an average of 50 lifts per crew. Only three incidents resulted in fatalities or injuries, with seven pilots killed during the training.^[20] When the Tetrarch was re-designated as an airborne tank, several changes were made to its design. A number of tanks had their 2 pounder guns replaced with a 76.2-millimetre (3.00 in) infantry support howitzer; these tanks were then designated as Tetrarch 1 CS (Close Support). Additionally, Littlejohn adaptors were added to those Tetrarchs which still possessed their 2 pounders to increase their muzzle velocity and armour penetration.^[5]

Russian Light Tank T-26 (Tier II)

The T-26 tank was a Soviet light infantry tank used during many conflicts of the 1930s as well as during World War II. It was a development of the BritishVickers 6-Ton tank and is widely considered one of the most successful tank designs of the 1930s.^[3]

It was produced in greater numbers than any other tank of the period, with more than 11,000 manufactured.^[4] During the 1930s, the USSR developed a record number of 53 variants of the T-26, including different combat vehicles based on its chassis (flame-throwing tanks, combat engineer vehicles, remotely controlled tanks, self-propelled guns, artillery tractors, armoured carriers). Twenty-three of these were series-produced, others were experimental models.^[5]

The T-26 together with the BT was the main tank of the Red Army's armored forces during the interwar period. Though nearly obsolete by the beginning ofWorld War II, the T-26 was the most important tank of the Spanish Civil Warand played a significant role during the Battle of Lake Khasan in 1938 as well as in the Winter War in 1939–40. The T-26 was the most numerous tank in the Red Army's armored force during the German invasion of the Soviet Union in June 1941.^[6] The T-26 participated in combats with the Germans and their allies during the Battle of Moscow in winter 1941/1942, the Battle of Stalingradand the Battle of the Caucasus in 1942–1943; some tank units of theLeningrad Front used their T-26s until 1944. The Soviet T-26 light tanks last saw use in August 1945, during the Soviet invasion of Manchuria.^[7]

The T-26 was exported and used extensively in the armies of Spain, China and Turkey. In addition, captured T-26 light tanks were used by the Finnish, German, Romanian and Hungarian armies.^[8]

The T-26 was reliable and simple to maintain, and its design was continually modernised between 1931 and 1941. However, no new models of the T-26 were developed after 1940.

Type	Light infantry tank
Place of origin	Soviet Union
Service history
In service	1931–1945 in USSR 1936–1953 in Spain 1940–1961 in Finland
Used by	Soviet Union  Spanish Republic  Finland  Republic of China  Turkey  Nazi Germany  Kingdom of Romania  Kingdom of Hungary  Afghanistan
Wars	Spanish Civil War Second Sino-Japanese War Soviet–Japanese Border Wars World War II Soviet invasion of Poland Winter War Eastern Front (World War II) Anglo-Soviet invasion of Iran Soviet invasion of Manchuria Chinese Civil War
Production history
Designer	Vickers-Armstrongs, OKMO ofBolshevik Plant in Leningrad
Designed	1928–1931
Manufacturer	Factory No. 174 named after K.E. Voroshilov in Leningrad,Stalingrad Tractor Factory
Produced	1931–41
Number built	10,300 tanks and 1,701 other vehicles[1]
Specifications (T-26 mod. 1933[2])
Weight	9.6 tonnes (10.6 short tons)
Length	4.65 m (15 ft 3 in)
Width	2.44 m (8 ft)
Height	2.24 m (7 ft 4 in)
Crew	3 (commander, gunner, driver)
Armour	Bottom: 6 mm (0.24 in) Roof: 6–10 mm (0.24–0.39 in) Hull and Turret: 15 mm (0.59 in) (front, rear, sides)
Main armament	45 mm 20K mod. 1932/34 tank gun (122 rds.)
Secondary armament	7.62 mm DT tank machine gun(2,961 rds.)
Engine	4-cylinder gasoline flat air-cooledT-26 (Armstrong Siddeley type); engine volume 6,600 cc 90 hp (67 kW) at 2,100 rpm
Power/weight	9.38 hp/t
Transmission	single-disk main dry clutch, drive shaft, gearbox with five gears, steering clutches, final drives
Suspension	leaf quarter-elliptic springs
Ground clearance	380 mm (1 ft 3 in)
Fuel capacity	290 L (64 imp gal; 77 U.S. gal) [with additional 110-L fuel tank]
Operational range	Road: 220–240 km (140–150 mi) Off-road: 130–140 km (81–87 mi)
Speed	Paved: 31.1 km/h (19.3 mph) Gravel: 22 km/h (14 mph) Off-road: 16 km/h (9.9 mph)

British origin

The T-26 was a Soviet development of the British Vickers 6-Ton (Vickers Mk.E) light tank, which was designed by the Vickers-Armstrongs company in 1928–1929. The simple and easy to maintain Vickers 6-Ton was intended especially for export to less technically advanced countries: the Soviet Union, Poland, Brazil, Argentina, Japan, Thailand, China and many others. Vickers advertised the tank in military publications, and both the Soviet Union and Poland expressed interest in the Vickers design. In the spring ( Northern Hemisphere) of 1930, the Soviet buying committee, under the direction of Semyon Ginzburg, arrived in Great Britain to select tanks, tractors and cars for use in the Red Army. The Vickers 6-Ton was among four models of tanks selected by Soviet representatives during their visit to Vickers-Armstrongs. According to the contract signed on May 28, 1930, the company delivered to the USSR 15 twin-turreted Vickers Mk.E (Type A, armed with two .303 calibre (7.71 mm) water-cooled Vickers machine guns) tanks together with full technical documentation to enable series production of the tank in the USSR. The ability of the two turrets of the Type A to turn independently made it possible to fire to both the left and right at once, which was considered advantageous for breakthroughs of field entrenchments.^[9] Several Soviet engineers participated in assembly of the tanks at the Vickers Factory in 1930.^[10]

The first four Vickers 6-Ton tanks arrived in the USSR at the end of 1930. The last tanks did not arrive until 1932, when series production of the T-26 was already in progress. The British tanks were issued to Soviet factories for study in preparation for series production and to military educational institutions and training units. Later, some tanks were given to military supply depots and proving grounds.

The Vickers-built 6-Ton tanks had the designator V-26 in the USSR. Three British tanks were successfully tested for cross-country ability at the small proving ground near Moscow on Poklonnaya Hill in January 1931. Kliment Voroshilov ordered the creation of the "Special Commission for the Red Army (RKKA) new tanks" under the direction of S. Ginzburg to define the tank type suitable for the Red Army. The T-19 8-ton light infantry tank, developed by S. Ginzburg under that programme at theBolshevik Plant in Leningrad, was a competitor to the British Vickers 6-Ton. The first prototype of the complex and expensive T-19 was not finished until August 1931. Because both tanks had advantages and disadvantages, S. Ginzburg suggested developing a more powerful, hybrid tank (the so-called "improved" T-19) with the hull, home-developed engine and armament from the native T-19, and the transmission and chassis from the British Vickers 6-Ton.^[9][11]

However, on January 26, 1931, I. Khalepsky (Head of the Department of Mechanisation and Motorisation of the RKKA) wrote a letter to S. Ginzburg with information obtained via the intelligence service that the Polish government had decided to purchase Vickers 6-Ton light infantry tanks as well as Christie M1931 cavalry tanks and to mass produce them with the assistance of both the British and French. Because Poland was then considered, in Soviet military doctrine, to be the USSR's main enemy, the Soviet Revolutionary Military Council took this erroneous information into consideration and decided to pass the aforementioned foreign tanks into Red Army service, starting their production immediately without waiting for completion of development works, in order to counter possible aggression. At that time, the RKKA had only several dozen outdated Mk.V, Mk.A and Renault FT-17 tanks, captured during theRussian Civil War, together with various armoured cars and obsolescent domestic MS-1 (T-18) light infantry tanks. On February 13, 1931, the Vickers 6-Ton light infantry tank, under the designator T-26, officially entered service in the Red Army as the "main tank for close support of combined arms units and tank units of High Command Reserve".^[9][11]

One of the Vickers 6-Ton tanks (equipped with Soviet-made turrets for the pilot batch T-26 tanks) was tested for gunfire resistance in August 1931. The hull was subjected to rifle and Maxim machine gun fire with the use of normal and armour-piercing bullets at a range of 50 m (160 ft). It was found that the armour withstood gunfire with minimal damage (only some rivets were damaged). Chemical analysis showed that the front armour plates were made from high-quality cemented armour (S.t.a Plat according to Vickers-Armstrongs classification), whereas the homogeneous roof and bottom armour plates were made from mediocre steel. Nevertheless, the British armour was better than armour produced by Izhora Factory for the first T-26s due to a shortage of modern metallurgical equipment in the USSR that time.^[12]

The prototype of TMM-1 light infantry tank during tests in spring 1932.

At the same time, the Faculty of Mechanisation and Motorisation of the Military Technical Academy named after F.E. Dzerzhinsky developed two tank models (TMM-1 and TMM-2) based on the purchased Vickers 6-Ton tank design but with an American Hercules 95 hp (71 kW) six-cylinder water-cooled engine, improved front armour (to 15–20 mm), and a driver's position on the left side. TMM stands for tank maloy moshchnosti or "tank of low power". The TMM-1 was equipped with transmission details from the native Ya-5 truck and a ball mount for the DT tank machine gun in front of the hull, whereas the TMM-2 was equipped with an improved gear box, a steering device without clutches and a 37 mm Hotchkiss gun in the right turret. However, representatives from the main Soviet tank manufacturers together with officials from the RKKA Mobilization Department considered the Hercules engine to be too difficult to produce, and the engine tended to overheat inside the engine compartment. Tests of TMM-1 and TMM-2 prototypes performed in the beginning of 1932 demonstrated no advantage over the Vickers 6-Ton and the T-26 (the TMM-2's maneuverability was found to be even worse).^[13][14]

The T-26 entered active service for the Red Army (RKKA) in 1932; it was used in many conflicts of 1930s as well as during World War II. The T-26 together with the BT was the main tank of the RKKA armored forces during the interwar period.

The T-26 light tank first saw action in the Spanish Civil War. The Soviet Union provided Republican Spain with a total of 281 T-26 mod. 1933 tanks starting in October 1936. T-26s were used in almost all military operations of the Spanish Civil War in 1936–1939 against Nationalists and demonstrated there a superiority over the German Panzer I light tanks and Italian CV-33 tankettes armed only with machine guns. During the battle of Guadalajara T-26s outclassed the Italian tankettes, strongly inspiring the design of the first Italian medium tank the Fiat M13/40 tank.

The first military operation of the RKKA in which T-26 light tanks participated was the Soviet-Japanese border conflict, the Battle of Lake Khasan, in July 1938. The 2nd Mechanised Brigade, the 32nd and the 40th Separate Tank Battalions had 257 T-26s, from which 76 tanks were damaged and 9 burnt towards the end of battle action. A small number of T-26 tanks and flame-throwing tanks based on the T-26 chassis participated in the Battle of Khalkhin Gol against Japanese forces in 1939.

On the eve of World War II, T-26s served mainly in separate light tank brigades (each brigade had 256–267 T-26s) and in separate tank battalions of rifle divisions (one company of T-26s consisted of 10-15 tanks). This was the type of tank units that participated in the Soviet invasion of Poland in September 1939 and in the Winter War of December 1939-March 1940. The Winter War proved that the T-26 was obsolete and its design reserve was totally depleted. Finnish anti-tank guns easily penetrated the T-26's thin anti-bullet armour, and tank units equipped with the T-26 suffered significant losses during the breakthrough of theMannerheim Line, in which the flame-throwing tanks based on the T-26 chassis played a significant role. On June 1st 1941 the Red Army had 10,268 T-26 light tanks of all models, including armoured combat vehicles based on the T-26 chassis. T-26s composed a majority of the fighting vehicles in Soviet mechanised corps of border military districts. For instance, the Western Special Military District had 1,136 T-26 tanks on June 22nd 1941 (52% of all tanks in the district). The T-26 (mod. 1938/39, especially) could withstand German tanks (except the Panzer III and Panzer IV) participating in Operation Barbarossa in June 1941. The majority of the Red Army's T-26s were lost in the first months of the German-Soviet War, mainly to enemy artillery and air strikes. Many tanks broke down for technical reasons and lack of spare parts.

Nevertheless, the remaining T-26s participated in combats with the Germans and their allies during the Battle of Moscow in winter 1941/1942, the Battle of Stalingrad and the Battle of the Caucasus in 1942–1943. Some tank units of the Leningrad Front used their T-26 tanks until 1944.

The defeat of the Japanese Kwantung Army in Manchuria in August 1945 was the last military operation in which Soviet T-26s were used.

In the 1930s, T-26 light tanks were delivered to Spain (281), China (82) and Turkey (60). They were used in the Second Sino-Japanese War by the Chinese in 1938–1944,exspecially in the Battle of Kunlun Pass. A number of captured T-26s of different models were used by the Finnish Army during the Continuation War, some tanks served in Finland until 1961. Captured T-26s were also used by the German, Romanian and Hungarian armies.