- Yes
- No
Brief Summary:
In an attempt to make improvements upon the T-26 chassis in the mid 1930’s the T-46 was born as one of the many attempts to replace the T-26 and like many of it’s contemporary prototypes would fail for various reasons in this vehicles case the production of the pilot vehicles would doom an otherwise quite well designed early T-26 replacement.
History:
Spoiler
With the T-26 being accepted into service with the Red Army on the 13th of February 1931 immediately replacing the older T-18 (also known as the MS-1) tank which was based upon the Renault FT-17, Although the T-26’s at this point were still largely based upon the Vickers Mk.E with the vehicles using two turrets armed with only machine guns there was already large plans to upgrade the tank in many directions.
By 1933 many noticeable improvements came to the T-26 that shaped the iconic look of the light tank with it’s single turret and 45mm gun however already questions of replacing the T-26 were raised in the summer of 1933 however this tank was also to resemble a T-26 to be able to make parts cheaper and reusable between models just like how the BT-5 used the same armament as the T-26 1933.
Draft design, November 1933
OKMO received the order for this vehicle on the 17th of August 1933 and work was to begin at factory #185 In Leningrad. N.V. Barykov became the director of this tank initially called the “T-26A” which had an estimated mass of 10 tons and use a 200-250hp engine allowing for a set top speed of 50km/h with tracks and 70km/h with wheels. The gun would remain the same as the T-26 and BT-5 in service.
100,000 rubbles was allocated to the development of the T-26A project however by October the deadline was proven to be very optimistic mainly due to the large quantity of projects being worked on at factory #185 as Leningrad became the centre of Soviet tank development which resulted in the T-28 and T-35 being developed alongside the T-26A project which at this point became the T-46 project as the T-26 was to receive further improvements and variants increasing the workload further with the amount of tanks begin designed and developed.
Preliminary design.
The lead engineer of the new project was M.V. Simskiy, M.P. Zigel also made large contributions to the project directed by the deputy chief designer O.M. Ivanov and Chief Designer S.A. Ginzburg. A draft of the T-46 project was finally ready on by the 30th of November 1933. The tank that appeared was completely different than what was originally intended for the requirements and almost nothing from the T-26 remained even as early as this stage of the project with most of the similarities being from the shape of the hull and turret being similar to it’s predecessor. Calculations at the time predicted the tank to weigh about 11 tons, with the dimensions being that of the BT-5 the proposed tank was theoretically able to replace both the T-26 and BT-5 by the designers at the time.
The new dimensions allowed a new engine the air cooled 300hp MT-5 engine also being developed at Factory #185 which would of given it an extra 210hp than the 90hp engine of the T-26 it was intended to replace. The new predicted top speed was predicted to be 50km/h tracked and 75km/h with wheels. Although now having a similar wheel design to that of the BT tanks the T-46 was to use a coil spring suspension and use a system of propeller shafts to power two wheels per side, rather than with one gear as found in the BT series.
Armament options where also allocated in the design of this tank with the turret able to fit the 76mm KT-28 or PS-3 guns as secondary options to give more flexibility to the project than being able to only arm the 45mm like the T-26, although at the same time a T-26 variant the T-26-4 was also in production which may of influenced this decision due to the T-26 needing a different turret to fit the 76mm KT-28 gun. the secondary armament was a KS-2 flamethrower.
With a meeting for the approval of the design on the 6th of December 1933 the tank would require extensive changes which dragged on throughout 1934. A letter on the 23rd of July 1934 from the Chief of the 2nd Department, UM Pavlovskiy of the 3rd Directorate which outlined 115 changes (initially 119 changes) which slowed the project down further.
280mm track on the T-46
A test around September 1934 which included aerodynamic covers being added to the T-46 to try and see if the tank could accelerate to 100km/h which was tested at the Zhukovskiy military aviation academy, no work beyond the trials was tested however it was an interesting idea at the time. One change proposed but ignored was the 280mm tracks which was deemed to small for the tank.
T-46 mock-up wind trials.
A prototype was due by November 1934 with a second tank in the first quarter of 1935 followed by mass production at factory #174 in 1936 however as of the 31st of October 1934, factory #185 estimated the deadline be delayed by 4 months due to the engine parts. Due to this the first prototype arrived in May of 1935 with the tank being quite different to what was initially proposed back in the Summer of 1933.
The prototype now weighed 15 tons primarily due to the armour being thicker than the drafts with it being the same as the T-26’s armour now, an extra machine gun was located on top of the turret which was similar to the AA machine guns being installed on the T-26 and BT-5’s around this time also. Only one wheel per side was needed to steer the tank now than the drafted designs two wheels.
The T-46 program was approved on the 26th of April 1935, the tank was intended to travel 2000km on wheels and tracks. By August 27th however the tank had only travelled 6km on tracks and 150km on wheels. One of the main reasons for this was the ignored issue of the 280mm tracks which were to narrow and was even warned by the Red Triangle rubber factory. Due to this the pitch of the track didn’t match the drive sprocket leading to the tracks constantly jamming up and slipping off. These tracks also had poor traction with the ground. After failed attempts of adjusting the crown which didn’t change the issue a compromise was made by using the tracks of the T-28 which even though added 426kg of weight to the vehicle resolved the majority of the issues and the ground pressure dropped significantly. The tank reached a top speed of 52km/h on wheels in third gear, the gearbox jumped out in fourth gear so it was not used.
A large list of corrections was composed as a result of these factory trials which were required for both the prototypes and pre-production tanks. The trails concluded on the 4th of October 1935 with a total distance of 1020km travelled, 374km on wheels and 646km on tracks. As the reliability increased the speed also increased with a new top speed of 82km/h on wheels accelerating to 73km/h in 40 seconds whilst the top speed on tracks was 56.3km/h with 51.5km/h attained within 35 seconds. the average speed was between 40-50km/h on a highway with wheels and 35-45km/h with tracks.
The tank could climb a 20 degree slope on wet muddy terrain with the T-28 tracks, a short 34 degree slope could also be conquered by the T-46. A 0.8m tall wall was also crossed in trials however the driver would hit his head on the dashboard after the climbing the wall.
First Prototype, September 1935
Although the tank turned out to be quite a success on the trails there were complains regarding the suspension, gearbox, transmission and controls. even if the tank had a range of 350-400km with wheels and 175-200km with tracks.
Same prototype with tracks.
Further testing was carried out on the 8th of October 1935 conducting military trails alongside the T-29 itself being intended to improve upon the T-28 like the T-46 with the T-26, the trials were conducted near Leningrad. Already travelling for 1034km before the trails it gained a further 270km during the military trials with the top speed on a rain soaked gravel highway being 58km/h. The average speed was 49km/h which was high for the time especially on tracks. The tank had drove for 31km until the crank arm of the rear left road broke due to a production defect.
Flamethrower located on the right side of the turret
The next stage of the trials took place on dirt roads and off-road to conduct the tanks ability in those situations, 17km/h was the average speed in the trails due to the conditions of the road quality such as a pothole riddled dirt road and road covered in 10-15cm of wet snow. The tank also crossed a swampy off-road terrain covered in 10-15cm of snow at the speed of 14km/h. The commission was satisfied in both cases which was good combat speeds of predicted combat.
Most defects at this time were more related to the production quality of the vehicle which had stopped the tank at many points on it’s trials but the tank. It could cross 2.5m wide trenches and 1m tall walls alongside 30 degrees being the maximum tilt the vehicle could take.
The tank had been accepted officially into commission on the 29th of February 1936 with preparations for mass production beginning with the cost of a T-26 being 200,000 rubbles compared to the 80,000 rubbles of a T-26 it was intended to replace.
Rear of the tank
The armament had changed the flamethrower to a KS-45 model in early February 1936 and a smoke generator was added to the rear. However the pilot vehicles had so many issues in being produced that the first pilot was not delivered till November 1936 with it still being worked on till March 1937 were it was finally finished. Due to constant changes to the pilot design the delays kept on going.
With the 4 pilot vehicles being produced finding so many defects that all four were deemed unsuitable for service and undergoing repairs in April 1937 and eventually the T-46 was scrapped in favour of the T-25 and T-35 light tank projects also intended to replace the T-26 and failing in 1938.
T-46-1 (pilot vehicle)
One T-46 ended up at the NIBT proving grounds and it’s fate is unknown, some of the vehicles were used as pillboxes and eventually one of the vehicles of the 4 would survive intact and is on display at the Central Museum of the Great Patriotic war (Victory Museum) In Moscow Russia although it isn’t completely like the original due to restorations. A second less intact T-46 is present at Kubinka.
T-46 as pillbox tank in 1941
Specifications:
Dimensions (L-W-H): 5.7x2.7x2.4m (18’7’’ x 8’9’’ x 7’9’’ ft)
Total Weight: 15.5-17.5 tons (sources differ on weight)
Crew: 3 (Driver, Gunner, Commander)
Propulsion: MT-5 petrol engine, 300-330hp engine (sources differ on the maximum hp of the engine)
Power to Weight Ratio: 17.14-21.29 hp/ton (depending on weight and hp source)
Suspension: Coil Spring Suspension
Top Speed: 58km/h (36 mph) tracked, 80km/h (49.7mph) with wheels
Main Armament: 45mm 20K (101 rounds), (some sources claim a 45mm L-46 was used)
Secondary Armament: 3x DT-29 7.62mm machineguns (located coaxially, roof mounted and rear mounted)
1x KS-45 flamethrower (located on the far right of the turret front)
Armour: The same armour as the T-26, 15mm maximum thickness.
Production: 4 vehicles
Additional Images:
Spoiler
T-46 prototype on trials
T-46 gearbox
T-46 engine damage on trials
Pilot T-46-1
Pilot T-46-1 rear
T-46-3 pilot under construction
Tank Encyclopedia’s interpretation of the T-46
Another Bunker T-46
T-46 being dug up at Karelian Isthmus
Restored T-46 displayed at the Victory Museum
Kubinka T-46
“Russian Tanks and Armoured Vehicles 1917-1945 an illustrated reference” by Wolfgang Fleischer
Sources:
(translated source from: Колёсно-гусеничный тупик | Warspot.ru )