T-12

Project Leaders

On December 20, 1927, the UMM of the Red Army formulated requirements for a new type of tank - the "maneuverable tank" with cannon-machine gun weapons in rotating towers. The development of a new tank was entrusted to the Design Bureau of the Kharkov Locomotive Plant named after the Comintern. The leadership of the team of engineers was headed by the chief designer of the State Clinical Hospital OAT S. Shukalov , the responsible executor of the project was V. Zaslavsky, the designer of the MTO was A. Mikulin.

The OAT was in no hurry with the implementation of this task and sought to shift the work to the KhPZ, from which the deputy chief engineer M. Andriyanov and the deputy head of the tractor workshop V. Dudka were responsible for creating the tank. The tank was directly supervised by engineer D. S. Makhonin.

Tank Description

The appearance was influenced by the experience of the Americans who created the T1E2 tank, in which a tiered arrangement of weapons was preferred (machine-gun tower on the roof of the main tower). The layout of the tank was quite dense, although it was higher in size and not comfortable enough for the crew.

The control compartment was located in front, behind it there was a combat compartment and a motor-transmission compartment. The large nine-sided tower was designed for a crew of 3 people, which included a commander, loader and machine gunner. A 45-mm cannon or a 57/60-mm howitzer could be placed in the frontal sheet of the tank. Two coaxial machine guns of Fedorov were placed on the sides, and in the upper tower (on the roof of the main one), shifted back, there was another spark of 7.62 mm machine guns. The power plant included a 200-horsepower Hispano-9 aircraft engine. The undercarriage was borrowed from French cars: 8 rollers on board (in 4 trolleys with vertical spring cushioning), 4 supporting rollers, rear driving and front steering wheels. The armor was up to 12 mm thick on the sides and up to 22 mm in front. The driver took his seat on the starboard side.

Assembly and Modification

The tank was going fast enough, but at the end of the assembly it was unexpectedly rebuilt. The nine-sided tower was replaced by a cylindrical one with a straight frontal sheet, and Hispano decided to replace the engine. It was originally planned to deliver the A. Mikulin design motor, but it was not possible to get it on time, and as an alternative, the M-6 aircraft engine was selected with a power of 180 to 200 horsepower. After installing a new engine, the gearbox was redone, and then tape floating brakes were replaced. The planetary gearbox made it possible to change the driving mode by both 15.7 and 2.7 km / h, while maintaining the possibility of reverse at all speeds. The hull was lengthened and equipped with a special “tail” to overcome ditches and trenches.

Construction was carried out from October 13, 1928 to October 15, 1929 , but the equipment took another two months. The tank was officially adopted in February 1930, and was presented for testing on April 2 . According to the RGVA, the tank went only 2 kilometers through the ground, because after that it lost its transmission. During these sea trials, the net engine run time was 33 minutes (of which 21 minutes were in motion). After the engine repair, the mechanics discovered malfunctions and defects in the chassis: overheating of the gearbox, boiling water in the radiator, failure of the second gear and breaking of the right track on soft ground. At the same time, the host tests noted a good ride.

From April 28 to May 2, 1930 , the next tests were held, attended by the People's Commissar of War K.E. Voroshilov , the head of the UMM I.A. Khalepsky and the head of the technical department of the UMM G.G.Bokis , as well as representatives from the KhPZ S. Makhonin and Vladimirov. In tests, the T-12 demonstrated its best capabilities, successfully passing through rough terrain and mastering the climb at an angle of 35-36 degrees in first gear. On the ground, the speed was 26 km / h, but with an increase in the engine speed to 2 thousand per minute, the speed reached 30 km / h. The tank managed to overcome a two-meter trench on sandy ground (potentially it could also cross a 2.65 m wide ditch).

It was not possible to carry out fire tests to the full extent: due to the lack of a Fedorov machine gun, a 7.7-mm Lewis machine gun was installed on the tank in a ball mount designed by Shpagin. Shooting accuracy was 60%. Cannon shooting did not pass due to the unavailability of the main gun. July 12, 1930 were repeated fire tests with a new gun. The full ammunition of the tank was only 100 rounds and 4,000 cartridges for machine guns, but if a full set of weapons were installed, it would be 98 rounds and 7,200 rounds. Also, shelling of the armored plate of the tank led to the conclusion that the protection of the tank corresponded to requirements. However, the problems identified in the first tests were not fully corrected.

The State Commission as a whole was pleased with the tank, however, it was recommended that it be finalized by increasing the range of the tank and correcting problems with the track and gearbox. The tank never entered service with the Red Army, but on the modified T-24 tank all the flaws were corrected.

• T-12. Medium tank