The design bureau of Nikolai Polikarpov in the 30s created a host of new models of military aircraft . The most famous of them, without a doubt, is the I-16 Ishak, which took an active part in the battles at the initial stages of World War II. Designers led by Polikarpov constantly improved existing models of technology and led the development of new machines. Shortly before the start of the war, I-180 and I-185 fighters were created, which became the last works of a brilliant aircraft designer.
New factory
In 1939, N. N. Polikarpov began an independent study of the fighter project for new two-row star-shaped engines with an air cooling system. Work on such engines with a capacity of about 1600 ... 2000 liters. from. led design bureaus S. K. Tumansky (engine model M71) and A. D. Shvetsov (model M81). The documentation for aircraft engines arrived at Polikarpov Design Bureau in the summer of 1939. A photo of the M71 motor below.
However, soon the designers from the bureau were assigned to other plants, and N. Polikarpov himself was assigned to the new pilot plant No. 51, located in the city of Stakhanov (currently Zhukovsky). In a new place, he had to combine the duties of director and chief designer. It was there, at a new place, N. Polikarpov developed the project "62" - the future I-185 fighter.
First option
To create a new promising aircraft required a powerful engine. At that time, only the M88 serial engine was available, but its characteristics were clearly insufficient. The promising M90 and M71 engines had much more weight and fuel consumption, but could provide much higher aircraft speeds. To obtain acceptable takeoff and landing properties and maneuverability, the I-185 fighter project had developed wing mechanization, which included slats and flaps.
The first version of the aircraft was developed in the first three months of 1940 and provided for the installation of a 1750-horsepower 18-cylinder star-shaped air cooling engine M90. A distinctive feature of the motor was a small diameter - a little less than 1300 mm. For the 185 fighter, Polikarpov developed a fundamentally new hood, equipped with a central entrance (which was never implemented) and a fan in the frontal part. The first copy of the aircraft was built by the end of May 1940, but there was no engine suitable for flights at that time.
With another motor
To speed up work on the aircraft, a 2000-horsepower 18-cylinder star-shaped air-cooled M71 motor was installed on the aircraft. The engine had a significantly larger weight and outer diameter, which required a change in the number of nodes of the fighter I 185. Tech. performance with the new engine was high - according to calculations, the plane had to reach speeds of about 665 km / h in horizontal flight. A photo of the I-185 fighter with the M71 engine can be seen below.
But the supply of air-conditioned copies of the M71 was constantly pushed back, so the M81 engine was offered to equip the fighter. The engine was a two-row 14-cylinder 1600-strong “star” with air cooling. The dimensions of the M81 cylinders were completely identical to the parts of the M71. The maximum speed, according to calculations, was reduced to a value of 610 km / h, but the construction of a machine with such a motor was considered advisable.
First flights
After finalizing the incoming engine (the crankshaft was damaged on it), it was installed on the I-185 fighter. In early January 1941, the car first flew into the sky, showing a speed of 495 km / h at ground level. The result obtained was almost consistent with the calculated data. A total of 16 flights were made, after which the M81 engine was recognized as unpromising.
In February-March, two long-awaited M71 arrived, which had more than the calculated weight and less power. It was they who were installed on two prototypes of I-185. An attempt to fly with a new engine was made in April 1941, but it was unsuccessful - the speed controller constantly refused on the engine. At the same time, problems with the power system became clear - the carburetor used was found unsuitable for flying.
Another engine
In early May 1941, N. Polikarpov received the task of equipping a promising aircraft with an M82 engine. The motor was a two-row 14-cylinder “star” with a small outer diameter (1260 mm in total). To solve this problem, two projects were created - under the existing fuselage and under the elongated, with a smaller cross-section. The second option made it possible to achieve high speeds, and therefore it was accepted for further work.
The new aircraft received the designation I-185 M82A and had armament consisting of three 20 mm ShVAK guns and two 7.62 mm ShKAS machine guns with synchronizers. As additional weapons could be used two machine guns ShKAS in the wings of a fighter. The first flight of the car took place in August 1941. The plane did not have planned machine guns and had radiators for cooling oil located under the fuselage. A car with an M82A engine - in the photo below.
Tests of the new machine were carried out in parallel with the I-185 with the M71 engine. This aircraft, despite ongoing problems with the power plant, developed a speed of up to 620 km / h.
Work in evacuation
At the end of October 1941, plant No. 51 and the design bureau of N. Polikarpov were evacuated to Novosibirsk. The development of the available prototypes I 185 continued at a new place. In February-March 1942, two machines equipped with M71 and M82A motors were tested jointly.
The machine with the M71 engine received the highest marks from test pilots. According to the commission, the car was recognized as fully meeting the requirements and recommended for mass production. After testing, the aircraft were flown around by pilots who had front-line experience, which also confirmed the high quality of the aircraft. But mass production never started.
At the front
By the summer of 1942, only a reference copy of the I-185 machine with the M71 engine was built, which, after a long fine-tuning, entered the Air Force Research Institute. In November 1942, military trials of several machines with M71 and M82A engines began. Tests were carried out as part of a 728 fighter regiment. The pilots once again confirmed the high flight qualities of the aircraft and the simplicity of piloting. A photo of the I-185 cab is presented below.
The I-185 reference model with the M71 engine showed a speed of 667 km / h in horizontal flight, which far exceeded the performance of other machines. Testing the machine was conducted by the pilot of the Air Force Research Institute P. M. Stefanovsky. In December 1942, he managed to disperse a plane weighted by 85 kg to a steady speed of 680 km / h. In some moments, the speed was more than 700 km / h, but it was not possible to keep it due to problems with the engine. According to the test results, the aircraft was recommended for use after the elimination of the list of defects in the design of the airframe and engine. The photo shows a scale model of the I-185 aircraft with the M71 engine.
End of project
By the end of January 1943, working drawings were issued and a place for production was selected - Plant No. 81 in Moscow. At the same time, the elimination of defects and work to reduce take-off weight was going on. But N. Polikarpov continued to create new versions of the machine - in February 1943 there were sketches of new I-187 fighters with the M-71 (or M-71F) engine and I-188 with the M-90 engine. Machines were supposed to have even greater flight speed and carry powerful weapons from four guns.
However, mass production of the I-185 fighter did not begin again. There were many reasons - the competition between Polikarpov Design Bureau and Yakovlev Design Bureau, and the lack of mass production of the M71 motor. Additional problems were due to the unknown real range of the car. In the spring of 1943, the I-185 aircraft under the control of test pilot V. A. Stepanchenko got into an accident and crashed. The pilot is seriously injured and dies. This accident became the main reason for the cessation of work on a promising machine.