Category: WW2 Soviet Light Tank Prototypes

Soviet Union (1942)
Light Tank – 1 Prototype Built

Introduction

Excellent frontal view of the T-45 – Credit: warspot.ru
The T-45 was a Soviet WWII light tank project, meant as a stop-gap measure until the T-70 could enter production. It was based on the lesser T-60, but with a new gun, turret and engine. While the T-45 didn’t have any glaring deficiencies and was superior to the T-60, it was nevertheless inferior to the T-70 in a number of aspects. However, there was no competition between the two, and the order to switch to T-70 production reduced the T-45 to a footnote in AFV history.

Background history

The NKTP found that Factory #37, based in Sverdlovsk, Ukraine, was unable to completely master T-70 production. This was an apparent issue from March 9, 1942 to late August, 1942. Another issue became apparent. Engines became a problem at Factory #37. They lacked GAZ-202 engines for their T-60s. The Gorky Automobile Plant (now known as GAZ) sent less engines than what was needed in the 1st quarter of 1942. This, in turn, delayed T-60 production. This sparked the theoretical idea of adding a ZIS-5 and/or ZIS-16 engine to T-60s produced by Factory #37.
Factory #37’s design bureau, headed by N.A. Popov, was tasked with designing the new vehicle. The design bureau was mostly made up of engineers who worked for Department #22 until their evacuation to Sverdlovsk. Department #22 worked on many tank projects and N.A. Popov, who also evacuated to Sverdlovsk, was the senior designer of the T-40 amphibious light tank.
The ZIS-16 (which came from a bus of the same name) was chosen as the new engine. The ZIS-16 engine received a new designation as the ZIS-60 for the tank version. This modified T-60 had an engine compartment which was easier to access, was less noisy, and had a top speed of 40.5 km/h which is one 1 km/h gained from the T-60 with the GAZ-202 engine installed. However, the engine had cooling problems. It also had modified final drives and a redesigned exhaust system. 5 of these new T-60s were ordered.
Factory #37’s military engineer 1st class, S.A.A. Afonin, mentioned this to the NKTP (People’s Commissariat of Tank Industry) during a meeting on May 14, 1942. He also conveyed the idea of adding a 45mm gun and increasing the armor to 35mm, which started the idea of the T-45. To Factory #37’s disappointment, these modifications and proposals were seen negatively by the NKTP.  With this combination, this T-60 variant was still inferior to the T-70 in terms of armor, engine power, and mobility. Since this would increase the weight of the vehicle, the engine, transmission, and suspension would suffer from further stress. The NKTP would not recommend this T-60 variant.
By the end of the meeting, Factory #37 was told to perform a trial of 200 km. After this task was completed, the results were to be sent to the Main Directorate of Armored Forces (GABTU) for evaluation. In the meantime, no more prototypes were allowed to be constructed.
It seems like Factory #37 started from scratch during or shortly after the meeting. This time they would actually install the 45mm gun, a new turret, and increase the armor thickness of the hull. This became known as the T-45.

T-45 prototype sitting in the yard of Factory #37 in 1942 – Credits: warspot.ru
S.A. Ginzburg, lead designer of the T-50 light tank and deputy director of the NKTP, joined the factory’s design team around April, 1942. Ginzburg sought to produce a light SPG based on the T-60 chassis, which matched the Factory #37’s goal. However, the T-45 was mostly complete by then.

Motivation behind the T-45

Upon the T-70s entry into mass-production, the Gorky Automobile Plant would have to produce twice as many engines GAZ-202 engines, as the new light tank used two of them. However, the factory was already having problems supplying them, and this in turn caused delay to the delivery of the tanks to the Red Army.
The T-70 required 1440 new types of parts, the creation of 545 new dies (basically a stamping tool), 825 new devices and 2300 new tools to start production. The T-45 required 224 new parts, 104 new dies, 175 new devices, and 255 tools. However, the T-45 borrowed 132 parts. 85 dies. 149 devices, and 433 tools from the T-70.
This meant that tank production wouldn’t be significantly disturbed by the introduction of the vehicle, which was superior to the T-60 on which it was based. The T-45 offered superior weaponry, and armor compared to the T-60, and it would have used an engine that was easier to obtain, as the factory which produced it was closer.

Protection

Compared to the T-60, the T-45’s hull armor was mostly the same with the exception of the sloping of the upper front plate, that had 25mm of armor instead of 15mm. If it was ever needed, the flat front plate could be up-armored from 35mm to 45mm. The increase of armor made the protection almost on par with the T-70. The armor thickness of the side of the T-45’s turret was 35mm. The driver’s hatch now swiveled to the side in a similar fashion to the Panther’s cupola. The T-45’s side plates was also riveted opposed to being welded (it is highly likely that this would’ve changed during production).

The T-45’s 45 mm gun can be easily seen when the hatch is open – Credits: warspot.ru

Firepower

The T-45 was armed with a 45mm 20K Model 1938 and a coaxial DT machine gun. This setup was very common among Soviet light tanks, as well as on the T-70.
The first trials were held on May 20th, 1942. The firepower was tested. The T-45 achieved 7-8 shells per minute when standing still and 3 shells per minute when on the move. The turret tended to sink inside the hull due to its weight. Despite the sinking turret, it allegedly managed to hit all 25 of its shells at the target at an unknown range.
The TMPF sight was planned to be replaced with the standard TOP 45mm sight.

Illustration of the T-45

Mobility

The T-45 received the inferior, but common ZIS-5 engine (the engine already traveled 12,000 km) which was ripped from a truck. The ZIS-16 engine was in short supply as they only had one left. Unfortunately, the top speed decreased to 37.2 km/h. It also received final drives and steering clutches from the T-70. New, strengthened torsion bars were added alleviate the added weight (weight 7 tonnes).
Driving trials were performed for seven days, from the 6th to the 13th of June. In total, it traveled 1505 km; 189 km on asphalt roads, 805 km on gravel, 410 km on rubble, and 110 km on dirt roads. The trials revealed several defects, such as the cooling fans malfunctioning twice, the engine working at high RPMs (which increases the chances of it breaking down), tires occasionally slipping off the wheel, and the track links breaking several times. The quality of the track links reflected on Factory #183, which manufactured them, and not Factory #37. The trials were successful otherwise with the exception of a few complaints that were listed earlier, especially given the old ZIS-5 engine that already had 12,000 km on it.
Upon successful termination of the trials and if the GABTU gave its blessing, the Miass factory, based in Miass, Chelyabinsk Oblast, Russia, would’ve produced the T-45’s ZIS-5 engine along with the transmission. The ZIS-16 engine would probably replaced the ZIS-5 once it’s production would have been properly set-up. However, since the T-45 was never placed into service, production of the engine and the transmission never occurred.

The T-45’s riveted side armor is clearly seen – Credits: warspot.ru

Conclusion

The data of the trial was sent to GABTU by the end of June, 1942. This data included both the T-45 and the T-60 with the ZIS-16 engine.
Factory #37 already struggled at producing T-60s. 321 semi-completed T-60s were produced in June, but only 109 were fully complete in June. The rest lacked tracks and armaments. The goal at the factory was supposed to be 200 complete T-60s.
Central Command’s new rule named #1958ss “Regarding T-34 and T-70 Tank Production” forced Factory #37 to cancel all T-60 production and to switch to the T-70.  Prior to this, Factory #37 only built 10 T-60s in July. After they switched, scarcity of parts became more and more obvious. This sealed the fate of the T-45 project.
The T-45 didn’t suffer from any condemning defects and some of the characteristics were largely on par with the T-70.
Whatever small advantages the T-45 could bring to the table could not convince the Soviet command to add yet another light tank into service. This would have complicated both maintenance and production in a moment when the Soviets needed as many tanks as possible as fast as possible.
Ultimately, the T-45 was born and quietly faded in the shadow of the T-70, without having a chance of proving itself.’
The remaining prototype was sent into battle where it was most likely destroyed.

Sources

“T-60 and Related Vehicles” by Yuri Pasholok
Article on the T-45 by Yuri Pasholok
Special thanks for Yuri Pasholok for helping us out and to Nikita Nikitenko for translating!

T-45 specifications
Dimensions	4.12 x 2.34 x 1.8 m (14’24” x 7’68” x 5’9” ft)
Total weight, battle ready	7 tons
Crew	2 (driver and commander)
Propulsion	73-76 hp ZIS-5 engine or 85mm ZIS-16 engine (theoretical)
Suspension	torsion bar
Speed (road)	37.2 km/h (23 mph)
Armament	45mm 20K Model 1938
Armor	25mm upper sloped plate 35mm or 45mm (theoretical) flat front plate 35mm turret side
Total production	1 prototype

T-45 schematic – Credits: Dmitry Shuvalov

Pilot standing beside the T-45 – Credits: warspot.ru

ww2 Soviet Tanks Poster

Soviet Union (1933-1936)
Light Tank – 4 Built + Prototypes

The BT meets the T-26

The T-46 was an attempt to fix the low mobility of the T-26 by adapting the design to include the BT’s Christie suspension. However, there were many problems – with thin armor, huge production costs, and little overall benefits over the BT series, it was deemed a failure, and the project was canceled.
The OKMO experimental design bureau was eventually broken up by 1939, but the story of the T-46 does not end there, as some T-46s apparently saw service in 1940 against Finland and possibly Germany, as static bunkers. Information on both the T-46 is incredibly scarce and often unverified. This article may include some inaccurate information, but at no point will unverified information be presented as anything other than that.

T-46, shown here using wheeled drive. Note the hang-rail antenna on the turret. This version has the lamp housing in the center of the upper glacis.

Design process

In mid 1930’s the Soviet military elite believed that the Christie suspension used on the BT series of tanks was the most ideal system for a fast “cruiser” tank, and the ability to remove the tracks and drive on road wheels was equally desirable.
The BT-7, for example, could drive as fast as 72 km/h (45 mph) without tracks, while the most common tank in the Soviet forces at the time, T-26, could only achieve a measly 31 km/h (19 mph) on pavement, and about half that off-road. So it is not surprising that in 1932 VAMM (Military Mechanization Academy) was tasked with developing a version of T-26 with Christie suspension and wheeled (track-less) drive. The academy soon produced a prototype named KT-26 (K for Kolesnyi, or wheeled).

A rare clear image of the Soviet T-46 tank.
However, the suspension improvements increased the weight of the tank as well, and seeing how it still used the 90 hp engine of the T-26, it produced a disappointing 40 km/h (25 mph). Only a scale model was built and the project was stopped. But the Soviet government was not about to give up on the idea.
In 1933 the same task was given to the Department of Experimental Vehicles, or OKMO, at Leningrad Factory #174. OKMO was soon moved to Leningrad Factory #185 (a.k.a. Kirov Plant) where by 1935 the first prototype was ready, by then given the designation T-46. It too was not perfect: while designing the new hull and turret, larger than those of T-26, the weight of the tank increased to 14-15 tonnes. As the gearbox and the final drive gears were designed with a 10-tonne tank in mind, the weight placed unacceptable stress on the mechanisms, and even the new 200 hp engine, planned in gasoline and diesel variants, could not solve this issue.
Three plans of improvement were proposed, designated 46-1, 46-2, and 46-3. The latter of those, 46-3, was chosen, and received official designation of T-46-1. The original prototype was redesigned with the extra weight in mind, which now approached 17.5 tonnes. To improve mobility the new MT-5 (sources differ, Svirin: 300 hp, Solyankin: 330 hp) gasoline engine was installed. A prototype performed admirably during trials.
This version was accepted for production and the factory received an order to produce 50 vehicles. However, the large number of technological improvements turned the cheap T-26 into a prohibitively expensive machine, and a senior official was quoted equating the cost of a T-46-1 to the triple-turreted T-28. According to several sources, only 4 serial vehicles were built in November-December of 1936.

Layout

The layout of T-46-1 is similar to that of a T-26 with many improvements. The most obvious was the replacement of T-26 twin-bogie suspension with Christie suspension, with 4 wheels on each side. The tracks could be removed and the tank driven on wheels. During wheeled drive the rear-most pair of wheels drove the tank, and the front-most steered using a differential. The tank featured levers for tracked mode and a steering wheel for wheeled mode.
Its 390 mm wide tracks were an improvement over the 260 mm T-26 tracks. A noted feature of the new powerful engine was that it required only grade 2 (low-octane) gasoline, as opposed to the high-octane fuel needed for T-26.

Both the hull and the turret were enlarged. The design intended for the tank to be welded, but all images show riveted construction. 15 mm armor plates were used for vertical surfaces, and 8 mm elsewhere. The larger turret was designed to accept either the widely used 45 mm 20K gun or the short-barreled 76 mm PS-3 gun. The latter gun would turn T-46 into an artillery support tank similar to a BT-7A. However, there are no records of this gun ever being installed on T-46.

The tank carried three DT-29 machine guns: one was coaxial to the main gun, the second installed in the rear of the turret, and the third MG stowed for anti-aircraft use. A KS-45 flamethrower was installed to the immediate right of the main gun, although on some images the flamethrower port is covered with a metal cover. The enlarged turret bustle now housed a radio set (71-TK-1), and some pictures of T-46-1 show the “hang-rail” turret antenna.

Further development and variants

Please keep in mind that the information on improvements and variants comes largely from a single source, that being either “Soviet Light Tanks, 1920-1941” or “Soviet Flame and Chemical Tanks, 1929-1945”, both by the same team of writers featuring A.G. Solyankin, M.V. Pavlov, I.V. Pavlov, and E.G. Zheltov.
According to these sources, the first improved modification was designated T-46-2 and would feature various armor improvements, a conical turret, gun stabilizer, and improved transmission and tracks. A major improvement in the next version, designated T-46-3, was the addition of sloped armor. One hull was built and subjected to testing at the Izhora Factory range. Solyankin provides a blueprint of this project, as well as a photograph of the hull.

Solyankin provides a blueprint for a T-46-3 tank, according to him, a further improvement of T-46-1 tank with sloped armor.
Other projects apparently included a chemical (dedicated flamethrower) tank called KhT-46, with increased range and 500 liters of flamethrower fuel, compared to the 50 liters on the regular T-46. Also in development were a command tank (T-46-4) and a self-propelled support tank with the 76.2 mm PS-3 cannon (AT-2). There is no substantial evidence that any of these vehicles existed. One version that did exist, however, was T-46-5, also known as T-111, a tank with much better protection but having little in common with T-46-1, besides the name.
In summary, the T-46 was expensive and did not offer many benefits over the rival BT series. But it is possible that T-46 provided Soviet engineers with experience that led to work on other prototypes, such as T-126, T-127, BT-IS, BT-SV, A-20 and A-32, eventually leading to the legendary T-34.

Operational History

This is where the history of the T-46 becomes very murky. In “Tough Armor: History of Soviet Tanks” Svirin notes that the production vehicles went to combat trials, where they remained for around a year and proved themselves as “very good” vehicles, even outperforming the BT in wheeled performance. What happened next is unknown. Years later it became known that at least two vehicles were used as dug-in emplacements.
One of those vehicles was restored by Russian Defense Ministry in 2004 and is now displayed at Central Museum of the Great Patriotic War 1941 – 1945 in Moscow, missing its tracks, wheels, and suspension but otherwise seemingly intact. The plaque next to the exhibit states that it was found on by the association ‘Vysota’ in the Karelia Isthmus near the village of Sosnovo, Leningrad Oblast.
Another T-46-1 is a partial hull donated to Kubinka in June 2013. The latter, according to an article by Komsomolskaya Pravda, was found at a scrap metal collection point – information which the source says is unconfirmed. It was then purchased by a third foreign party, until Dmitriy Bushkakov, an antique store owner, bought it from them for the museum. It does show that there may be more undiscovered T-46 tanks buried in an old hill somewhere. One can hope, at least.

A T-46 is being used somewhere as a dug-in emplacement, probably somewhere along the Soviet-Finnish border. The hang-rail antenna (if it had been installed) is gone, and so are the two periscopes. The gun, like in every image of T-46, is a 45 mm 20K.
An article by DrTankMan
Sources:
“Tough Armor: History of the Soviet Tank 1919-1937” Mikhail Svirin / “Броня крепка: История советского танка 1919-1937” Михаил Свирин.
“Soviet Light Tanks 1920-1941” A.G. Solyankin, M.V. Pavlov, I.V. Pavlov, E.G. Zheltov / “Советские легкие танки 1920-1941. А.Г. Солянкин“, М.В. Павлов, И.В. Павлов, Е. Г. Желтов.
“Soviet Flame and Chemical Tanks 1929-1945”  A.G. Solyankin, M.V. Pavlov, I.V. Pavlov, E.G. Zheltov / “Советские огнеметные и химические танки 1929-1945” А.Г. Солянкин, М.В. Павлов, И.В. Павлов, Е. Г. Желтов.
“Russian Tanks and Armored Vehicles 1917-1945 – an illustrated reference” by Wolfgang Fleischer.
The T-46 on Russian Wikipedia
aviarmor.net
kp.ru
dogswar.ru
mihalchuk-1974.livejournal.com
alternathistory.com

T-46-1 estimated specification
Dimensions (L-w-h)	5.7m x 2.7m x 2.4m (19ft x 9ft x 8ft)
Total weight, battle ready	17.5 tonnes
Crew	3
Propulsion	MT-5 330 hp petrol engine
Speed (road)	Tracks: 58 km/h (36 mph), Wheels: 80 km/h (50 mph)
Range	Road, tracks: 220 km (137 mi) Road, wheels: 400 km (249 mi)
Armament	Main: 45 mm 20K cannon (101 rounds) Secondary: 3 x DT-29 7.62 mm machine guns and KS-45 flamethrower.
Armor	15mm
Total production	Four, plus prototypes

Tanks Encyclopedia’s rendition of the Soviet T-46 light tank.

T-46-1, the “production” version of which 4 total were probably produced. The caption (from Solyankin’s “Soviet Flame and Chemical Tanks”) labels it as a “flamethrower tank”, but its flamethrower capability was limited to 12-13 shots. Svirin labels the same image in his book as “T-46A”.
The rear of the T-46-1. Notice the rear mounted DT machine gun.

Side-view of the T-46-1.

A more modern image of a T-46-1. According to the image author, it was taken at Karelian Isthmus. This one reportedly ended up in the museum at Poklonnaya Gora. No antenna or periscopes. The removed barrel was probably that of a 45 mm 20K.

The T-46-1 from the image above, being pulled from the ground. There is a Japanese website hosting a number of close-up images of this particular tank before it was restored can be found

Surviving T-46

This Surviving T-46 is now on display at the Central Museum of the Great Patriotic War 1941 – 1945. Photo credit
This one has the antenna and the periscopes, but they were likely mock parts fitted during restoration, as they look different from the original photographs.

A rear view of the restored T-46-1. It is the same tank as in previous image. It is unknown whether the number is historical. The rear-facing MG is visible, but the turret door looks different from previous images. It is likely a restoration replacement since it was seen missing on a previous image.

The other recovered hull in Kubinka, after being saved from a scrap yard (presented at the museum as T-46/1). The hull and the turret are facing forward. This hull is missing its upper glacis, the driver’s box, and the gun mantlet. A display to the left of the tank tells the story of its retrieval; however, there does not seem to be a high-resolution image of the display available online.

Another image from Solyankin’s “Soviet Light Tanks 1920-1941”. According to the book, one hull of T-46-3 was completed and tested at Izhora Factory range.

The T-46-5 or T-111 was a related prototype which was developed alongside the T-46. It was built in 1938, but was deemed unsatisfactory. It was one of the precursors to the T-34.

This image appears in “Russian Tanks and Armored Vehicles 1917-1945 – an Illustrated Reference” by Wolfgang Fleischer, where it is labeled as a T-46-1 tank. While vaguely resembling a T-46-1, it has a few differences: the turret appears conical, the main armament is a strange unidentified gun and not the usual 45 mm 20K, and the driver is armed with a machine gun. Either this is an image of one of the prototypes, or the illustrator did not have a good reference image for the T-46-1.

ww2 Soviet Tanks Poster

Soviet Union (1942)
Flying Tank – 1 Prototype Built

The Flying Tanks Concept

The idea of having a tank which could fly was first seen around in the early 1930s with Walter Christie’s flying M1928 tank, but other designs were made during WW2. The UK (Baynes Bat, 1943), Japan (Special Number 3 Light Tank Ku-R0 with a Kokusai Ku-8 glider, 1944), and the USSR (Antonov A-40, 1942), all attempted to make flying tanks, but none were successful. What each nation wanted was a fairly potent AFV which could fly into battle – something, even on paper, impossible. Having a large enough armament (larger than 12.7mm in caliber), and strong enough armor (at least 20mm) simply meant that the vehicle would be so heavy, that it could not possibly fly.

The Flying T-60

The Antonov A-40 (sometimes referred to as the A-40T or Krylya Tank, “tank wings”) was the Soviet attempt in 1942 to create a flying tank – only one prototype was produced. Soviet forces had originally strapped tanks and armored cars, such as the T-27, T-37A, and D-8, to the bottom of TB-3 bombers, and dropped them from a very short height; as long as the gear was in neutral, the tank would not break on impact. However, this required the crew to be dropped separately, which meant that the tank’s deployment was delayed. As a result of this, the Soviet Air Force ordered Oleg Antonov to design a glider for landing tanks…

Design

Antonov came up with a very ingenious solution. He added a detachable cradle to a T-60 bearing large wood and fabric biplane wings and a twin tail. The wingspan is estimated to be just over 59 ft (18m) and an overall area of  923.5 ft² (85.8m²). To put this in perspective as to how large it was, the small fighter aircraft, the Polikarpov I-16’s wingspan was 29 ft 6 in (9m), with an overall area of 156.1 ft² (14.5 m²) – the A-40’s wingspan was nearly double, and the overall area was nearly six times greater (although the A-40 cradle was dual-winged)!
The idea was for the A-40 to drop the cradle once deployed onto the battlefield – and this was necessary, for obvious reasons. No tank could possibly be deployed effectively in combat with near 60 foot wings sticking out of it. The wings would not only make the vehicle slower due to their weight, but they would create quite a lot of drag.
One T-60 placed into a glider in 1942, intended to be towed by a Petlyakov Pe-8 or a Tupolev TB-3. The tank was lightened for air use by removing its armament, ammunition and headlights, and leaving a very limited amount of fuel (and, according to some sources, its turret was also removed).

First Flight

According to the official story (which is dubious), there was a test flight on September 2, 1942. Even with the modifications, the A-40 was too heavy to be towed. A TB-3 bomber was towing it, but it had to ditch the glider to avoid crashing. The drag was simply too much, and the bomber could not handle the weight of its payload. The A-40 was piloted by the famous Soviet experimental glider pilot Sergei Anokhin, and, once ditched, it supposedly glided smoothly. The T-60 landed in a field near the airdrome it was being tested at, and after dropping the glider cradle, it was driven back to the base. There was no aircraft which could handle the weight of the vehicle, and therefore tow the A-40 at the correct speed (160km/h), and, for that reason, the project was abandoned.

Viability of the A-40

The first major problem with the Antonov A-40 is that it had huge wings. These would have to be ditched before combat, which would surely delay its combat deployment (although probably not nearly as much as dropping the crew separately). Secondly, if the vehicles were to only have limited fuel and no munitions, in order to be light enough to be dropped, then munitions and fuel would have to be dropped separately, thus meaning that the combat deployment is, yet again, delayed, because crews would have to scramble to get munitions and fuel loaded into the tank – and there is no guarantee that wind would not glide these airdrops away from their intended users.
Thirdly, the T-60 itself was not a particularly potent tank – not even in 1942. Its 20mm TNSh gun would only be viable for engaging lightly armored, or unarmored targets, and its armor, 20mm at best, could hardly withstand even the lightest of German AT guns.
Fourthly, it is unclear as to whether or not the vehicle was even successful. The official story, as recorded above, might be a gross exaggeration, or a total fantasy. The purported photo of the A-40 in flight is actually a drawing produced by the Antonov factory.

Rendition of the Antonov A-40. The colors are speculative, and it may be the case that some bare wood or tarp is showing.

A drawing (or perhaps a photograph of a model), of the A-40 in flight. This image was produced by the Antonov factory and is not, as some claim, a photograph of the real prototype. The T-60 appears to be an M1942 GAZ production, as shown by the stamped wheels.

A T-37 tank being dropped by a TB-3 bomber. It is incredibly low to the ground, which would make serious combat deployment dangerous, due to enemy fire.

A D-8 armored car strapped to the bottom of a TB-3 bomber during 1932 drills, Ukraine.