Leonid Kurchevsky - Dynamo-Reactive Gun DRP

In the 1930s, when the economy of the Soviet Union was developing rapidly, free money appeared and the opportunity to spend it on all sorts of projects and experiments. For example, radio-controlled airplanes, torpedo boats and tanks, mines exploded at a distance, unusual airborne techniques, rocket weapons. In the late 1930s, rumors about miracle weapons somehow fell through the earth on their own. However, by the beginning of the 1940s, the time of unbridled inventions was over, and the designers began to develop new and improved old weapons that the armies needed during the War.

The history of creation of recoilless artillery, whether dynamo-jet guns (DRP) as it was said in the USSR began in the mid-1920s, in the workshop of the laboratories of the Committee for Inventions, which was led by Leonid Kurchevsky.

A common problem when using a firearm is the recoil, or kick, experienced by a user. Recoil is the backward kick or force produced by a firearm upon discharge. When a gun, as a mechanical system, is fired, the bullet travels along the gun's barrel and exits its muzzle. The resulting reactive force is imparted to the gun in the form of recoil. Apart from the gun's recoil phenomenon which is caused upon firing in the chamber because of the bullet's charge, the produced explosion gives to the gun's frame an instantaneous kinetic energy, annihilating any inertia phenomenon.

Because of this recoil effect, the ability to fire multiple rounds accurately may be reduced. When an artillery weapon is fired, the energy of the round must be absorbed by the weapon's structure and eventually transmitted to the ground. Modern artillery systems incorporate recoil mechanisms to modulate the forces associated with these firings to a level that can be effectively and reliably supported by the structure. Conventional methods for mitigating weapon recoil include muzzle brakes and breech venting. With some recoil mechanisms, the energy of the round is dissipated by throttling fluid over the length of the recoil. The minimum level of this modulating force is directly proportional to the length of recoil.

Field guns are typically provided with a mechanism to accommodate the high recoil forces generated when firing a round. One known recoil accommodation mechanism involves slidably mounting the barrel within a cradle so that the barrel can slide along its axes relative to the cradle. When a round is fired from the barrel, the barrel can counteract the momentum of the fired projectile by sliding backwards from a firing position (equilibrium position). This reduces the peak stresses induced in the field gun. The barrel can then return to its firing position so the field gun is ready for firing another round.

Under Kurchevsky, who graduated from two courses in the Faculty of Mathematics and Physics, work was carried out on a variety of projects, such as: silent gun, air torpedo, electric machine - perpetual engine using the energy of atmospheric electricity, etc. Among other things L.V. Kurchevsky also wrote science fiction novels.

In 1923, L.V. Kurchevsky, apparently after familiarizing himself with the pre-revolutionary works of the designer D.P. Ryabushinsky, filed an application for the invention of the dynamo-reactive gun. Kurchevsky proposed to cut off the breech in the area of the bolt from a conventional gun and insert a Laval nozzle into the cut. The rest of the gun, including the rifled barrel, remained unchanged. The shell was placed in a conventional brass sleeve, in the bottom of which holes were drilled to exit the powder gases. The shutter was connected to the nozzle and shifted when loading. The gun had almost no recoil, and was much lighter than similar systems of this caliber. But then the designer didn’t manage to get close to the DRP.

On September 23, 1924, the OGPU arrested Kurchevsky. Leonid Vasilievich was suddenly accused of "plundering state property" (allegedly having spent government money without building the promised helicopter). Kurchevsky was convicted under Art. 108, 110, 113, 188 of the Criminal Code of the RSFSR to 10 years in prison. For serving the sentence sent to the Solovki Special Purpose Camp (SLON). Attempts to continue the work of the Commission of artillery experiments were not successful, and the experiments with such artillery systems were stopped. Over the next five years, he is actively working to restore the economy of the Solovetsky Islands, to create the transport and energy infrastructure of the camp. He was allowed to move freely in the campsite and even own a gun and hunt. While imprisoned in Solovki, Kurchevsky managed to give a good account of himself before the camp administration, on 03 January 1929 he was released early.

In 1929, Leonid Vasilyevich came to Podlipki [the city of Kaliningrad], to the artillery plant number 8 named after M.I.Kalinin, where they organized a special design office number 1. Kurchevsky's guns showed good results on field testing. They fired ammunition from regular guns, but they were an order of magnitude lighter than them.

Already in November 1929 M.N. Tukhachevsky, being the commander of the Leningrad Military District, "strongly urged the adoption of the battalion artillery of the DRP cannon." True, the chairman of the RVS of the USSR A.I.Egorov and the head of the Artillery Directorate of the Red Army G.I.Kulik recommended to refrain from adopting it. The dispute of the military leaders was resolved in the spring of 1931, after the appointment of Tukhachevsky as Deputy Commissar of the Military Enforcement - the Chief of Arms of the Red Army.

Tukhachevsky, holding the post of the Red Army chief of armaments, decided to completely rearm the Red Army artillery with recoilless guns. And in the period from 1931 to 1935 almost all of the artillery factories of the USSR worked on the instructions of Kurchevsky. And from that moment on, the activity of Kurchevsky began to go beyond the bounds of the reasonable.

In those same years, on his instructions, the Jet Research Institute was created, whose deputy director was SP Korolev, the future general designer of space rockets. According to his ideas about the maneuvering war of the future, Tukhachevsky planned to re-equip Soviet artillery and, in particular, to widely introduce recoilless guns.

Kurchevsky launched a vigorous activity, he literally bombarded the authorities, offering dozens of types of DRP capable, in his opinion, to replace all existing types of guns. This found a warm response from many high-ranking civilian and military leaders, and M.N. Tukhachevsky, who had no serious education, became the most ardent supporter of the DRP. Mikhail Nikolayevich so much believed in the DRP of Kurchevsky that he decided to re-equip the entire artillery of the Red Army, Navy and Air Force with them.

In 1932-1933, Kurchevsky managed to enlist the support of the People's Commissar of Heavy Industry, T.K.Ordzhonikidze, his deputy I.P. Pavlunovsky, Head of the Main Artillery Directorate, G.I.Kulik and monopolize everything. Stalin personally favored the designer and even presented Kurchevsky with a car.

Having himself gone through arrest and imprisonment, Kurchevsky fearlessly supported friends. According to the memoirs of M. F. Kurchevskaya, when in the autumn of 1930, Stechkin was arrested and convicted in the framework of the Industrial Party’s case, he helped his family in every way: he used to transport their things in his car, supply them with food and kerosene, Kurchevsky did not give a hand. A year later, thanks to the petition of Academician S. A. Chaplygin, Stechkin was early released and became one of the permanent employees and co-authors of Kurchevsky. The second time he will be arrested and will be in the "sharashka" after the death of Kurchevsky. Later, B.S. Stechkin, in turn, helped his friend's wife who had survived repression.

In 1932, the Kurchevsky team was transformed into the Special Design Bureau of the Red Army GAU. At the end of 1933, the KB-38, which was engaged in the design of classical artillery systems, was liquidated, the building and equipment were handed over to Kurchevsky, and the designer VG Grabin had to move to Nizhny Novgorod and start there anew. Kurchevsky was able to insist on his own and press down competitors. In 1934, the People's Commissariat of Emergency formed the Office of the Authorized Special Works (UUSR), which, of course, Leonid Vasilyevich became, and at plant No. 8 they began to manufacture PDA for installation on cars, light tanks, ships and aircraft.

It was assumed that the guns of Kurchevsky, in addition to field artillery, would replace conventional guns with a loaded barrel in anti-aircraft artillery, tank turret guns, anti-tank guns, and even casemate guns in fortified areas. However, it was not clear how to deal with the release of powder gases when firing through a nozzle in the breech of the PD, representing a great danger to the servants, especially in confined spaces.

In a short time many guns of all possible calibers were created. Kurchevsky DRP intended for all types of troops and were of two types: breech-loading with manual loading and automatic with burning sleeves made of nitrotex. Huge resources were spent on the development and launch into production of DRP.

In 1932-1935, virtually all the artillery factories of the country worked on Kurchevsky. His orders were made by plant number 8 (them. Kalinin, in Podlipki), plant them. Frunze (former St. Petersburg Arsenal), Leningrad Iron Works (LMZ), Kommunist plant (former Obukhovsky), Krasny Putilovets plant (former Putilovsky), etc. In the early to mid-30s, Kurchevsky’s cannons accounted for 30 to 50% of orders from artillery mills. DRP began to be massively supplied to the army.

By the mid-thirties there were up to 10its DRP systems of various caliber and purpose. Work was carried out on gauges from 37-mm to 500 mm. In addition to field artillery, a special fighter was built, armed with a 76-mm recoilless cannon ( I-12 ), a 305-mm howitzer mounted on a vehicle.

As noted by the honored inventor of the RSFSR S.D.Bogoslovsky, the design engineer and friend of L. V. Kurchevsky, “the crown of his work, which was ten years ahead of his time, was the guns he designed. We are talking about tools that worked on the reactive principle . "“Kurchevsky’s character developed in a passion for new, often daring ideas, in an effort to embody them by any means. Not a moment of stagnation and calm. Full disregard for clothing and appearance, for living conditions, money and well-being. His knowledge, mental acuity and susceptibility amazed scientists and inventors with whom he worked ... "

At the end of 1933, at the suggestion of M. Tukhachevsky, installation in one of the towers of the T-26 tank of the 76-mm recoilless gun of the Kurchevsky design was being worked out , but tests carried out on March 9, 1934 showed a number of drawbacks of such a gun - general structural incompetence, inconvenience loading on the move, the formation behind the gun when firing a jet of hot gases, dangerous for the accompanying infantry - as a result, further work in this direction was stopped.

In total, the artillery mills produced about 5,000 DRP. Of these, military acceptance took only about 2,000, and about 1,000 got into the troops. The situation was aggravated by the fact that Kurchevsky was constantly changing the drawings of the systems launched into production, the proportion of manufacturing defects was high. Manufactured samples of such guns had a large number of fatal flaws, their characteristics did not match the stated.

In January 1936 Machine-Building Plant No. 38 was visited by the Commander-in-Chief of the Air Force Ya.I.Alksnis and the chief engineer of the Main Aviation Industry Directorate A.N.Tupolev. Also, the activity of UUSR was studied by the Party Control Commission under the Central Committee of the CPSU(b). As a result of these checks in February 1936 the Office of the Special Representative was liquidated, and Kurchevsky was practically removed from work.

As the absurdity of the venture became more and more apparent to an ever wider circle of people involved in these ventures, the flow of negative information grew. The management of the factories, the military reception office, the testers at the test sites, the commanders of whose units imposed dubious equipment, wrote complaints. Tukhachevsky for a long time successfully prevented the government from getting this information.

Soon the "bubble" burst. It turned out that the armor-piercing shells of anti-tank DRP, even when fired at point blank, were not able to penetrate armor thicker than 30 mm. The accuracy and range of field artillery guns do not meet the requirements at all. At the same time, the guns themselves are unreliable and unsafe during operation, there had been numerous cases of rupture of barrels during firing.

Aircraft and naval automatic cannons of the Kurchevsky caliber from 37 to 152 mm gave constant failures and delays during firing due to incomplete combustion of the nitro-fabric sleeves and the unreliable operation of the pneumatic recharge mechanism, which made this weapon absolutely not combat-ready. Soon all PDDs were removed from the troops and destroyed. By June 22, 1941, there was not a single Kurchevsky gun in service with the Red Army.

Kurchevsky was arrested and charged with creating unpromising weapons since 1933 on the instructions of Tukhachevsky. Almost at the same time with Kurchevsky, Tukhachevsky, Pavlunovsky and almost the entire administration of the Red Army Directorate headed by the commander Yefimov were arrested. And in addition earlier, on February 18, 1937, Sergo Ordzhonikidze, the people's commissar of heavy industry, died or was killed. Of course, this whole company was arrested not at all for Kurchevsky’s adventure, but they are all responsible for what happened.

By one account, On November 25, 1937, the Military Collegium of the USSR Supreme Court of L.V. Kurchevsky was convicted under articles 58-7, 58-8 and 58-11 of the Criminal Code of the RSFSR and sentenced to the highest measure with confiscation of property. The next day, the court decision was enforced. Another account relates that it is documented that Leonid Vasilyevich was in prison until January 12, 1939.

On 18 February 1956, the Military Collegium of the Armed Forces of the USSR decides: to annul the sentence of November 25, 1937 in relation to Designer L.V.Kurchevsky, who was posthumously rehabilitated. After that, a wonderful legend was created about the very capable inventor of fantastic super-powerful guns, who in the 1930s was slandered by envious persons and fell victim to villains from the NKVD. Of course, he was neither a spy nor a pest, but neither the one nor the other would have caused the army such damage.

The adventurism of Kurchevsky and his high-ranking patrons cost the armed forces dearly, in addition to significant material losses on the production of obviously defective guns, the idea of recoillessness was discredited for many years. In 1942, when it became known about the appearance of recoilless guns abroad, Stalin uttered about this: "A child was splashed out with dirty water ..."

The recoilless tools of Kurchevsky were much cheaper to manufacture and significantly lighter than their counterparts of classical design. However, their range and rate of fire were lower. In addition, the reverse flame produced when fired posed a danger to the combat crew and unmasked the position. Recoilless guns, therefore, could only be used to solve special problems.