Combat aircraft. Flying IS-1
Preface required. We are talking about the 30s of the last century, when two ideologies clashed in the design bureaus of the whole world: a fast and maneuverable fighter. It simply did not work out right away at once, and it turned out that I had to work in two directions.
The maneuverable combat fighter was a biplane, high-speed - a monoplane.
Everything is fine here, physics, or rather, aerodynamics. Ball rules specific load on the wing, that is, the ratio of the weight of the aircraft to the wing area. And at these times, it was this parameter that determined in many respects the flight qualities of any aircraft.
Biplanes with a large wing area had a low separation speed and a short take-off, and in the sky they were very maneuverable. But you had to pay for it with a low speed of horizontal flight.
Monoplans, on the contrary, were faster in speed, but they needed longer runways and means of wing mechanization: slats, flaps, flaps, aerodynamic brakes.
Something average was clearly drawn, an airplane that could combine both a short take-off, and good maneuverability, and high speed.
Such an attempt was made by the former Soviet inventor Ivan Ivanovich Makhonin.
Until 1921, he lived and worked in Russia, but then was forced to leave for France, as he did not show interest in his projects, of which there were many.
In September 1929, Makhonin presented a draft monoplane with a variable wingspan. Just so, the length of the wing varied from 13 to 21 m, and the area from 19 to 33 square meters. m
The outer parts of the consoles could be telescopically retracted into the root parts of the wing when there was no need for excessive lifting force. Due to this, when flying at high speed, air resistance was significantly reduced. The first flight of the Mak.10 aircraft, equipped with a Lorraine 12Eb engine with a capacity of 480 hp, took place on August 11, 1931. After 4 years of testing, it was significantly upgraded and received a new Gnome K.14 engine (800 hp) and the designation Mak.101. The aircraft managed to reach a speed of 378 km / h.
This is the first aircraft in the world with variable wing geometry.
The Germans became interested in the plane. As soon as the occupation of France began, representatives of the Luftwaffe came to the Mahonin. Ivan Ivanovich flatly refused to cooperate, and the plane was confiscated. The car with the test pilot was taken to Rechlin for testing, where on the very first flight the French pilot, who shared "love" with the Germans with the Germans, crashed the plane to smithereens.
In this story The world's first aircraft with variable geometry of the wing is over, and we begin the history of the first successful aircraft of this family.
In general, the author of the aircraft project Vladimir Vasilyevich Shevchenko in the direct sense of the word was not a designer. Yes, he graduated from Moscow Higher Technical School, and even in the same group as Sergei Korolev, but the craving for heaven won in every sense. After graduating from VVTU in 1929, Shevchenko ended up in Odessa, and then served in the Air Force of the Red Army, flew on fighter R-1 and I-4.
Shevchenko proved to be a very good pilot, as evidenced by his participation in the air parades over Red Square as part of the links Stepanchonka on I-5 and Kokkinaki on I-16.
And since 1933 Shevchenko worked as a test pilot at the Air Force Research Institute of the Red Army, where he took part in the tests of many aircraft: I-16, I-153, R-5, Pe-8, Il-2, I-180, La-5 , Me-108, Me-110. And in 1939 he visited Germany, where he flew on the Ju-88 and FW-189.
Based on his very extensive experience, Shevchenko tried his hand at developing a new aircraft for those times, combining the properties of both a monoplane and a biplane.
Shevchenko’s idea was to fold the lower wing of the biplane after take-off, thereby turning it into a monoplane. In this case, the wheels were retracted into the side niches of the fuselage, the root part of the wing was also removed with a special lifting mechanism, and the end part fit into the recess of the lower part of the upper plane.
And Shevchenko submitted the outline calculations and drawings for consideration to the Air Force research collegium. The project was found to be very interesting and original, it was only embarrassing that this did not happen earlier in world practice. It had no analogues in the world, so to speak.
The project was given a go. Major Shevchenko, who immediately became a designer, was allocated a room in the old building of the Moscow Aviation Institute, organized financing (very modest at the time) and a team for building the layout.
Upon learning of the recognition of the Shevchenko project, the colleague was supported by outstanding pilots - Heroes of the Soviet Union Grigory Kravchenko, Stepan Suprun and Anatoly Serov.
And in April 1938, a group of pilots and engineers of the Air Force Research Institute was presented with a working model of a new aircraft, to which Shevchenko and the team working on the aircraft were given the name IS-1.
In the 60s, a version appeared that the IS-1 stands for “Foldable Fighter.” In fact, no, the confirmed evidence of Shakhurin and Poskrebyshev (Stalin’s secretary, if anyone doesn’t know) has been preserved that, in a report to Stalin, Shevchenko himself spoke about the initiative of the work collective to name the plane that way.
Stalin, by the way, did not particularly mind, but hinted that with this name the plane was simply obliged to fly and fly well.
But in 1938, the plane caused a stunning reaction from pilots who better than others understood the essence of the design.
There were also downsides. It required the highest precision in the manufacture of components and assemblies of the aircraft, especially hydraulics, which removes the wings. After all, the smallest backlash in the system could lead to an under-cleaning of the wing, and, consequently, to possible structural failures due to the incoming air flow.
In general, cleaning and releasing the lower wing was fraught with many surprises, often unpleasant. Folding on hinges and pulling up to the upper wing, the lower one moves for the entire seven seconds of the flight across the stream flowing around the aircraft. A complex drawing of takeoff and landing was drawn in terms of speed.
The current layout was examined by the People’s Commissar of Defense Voroshilov, Air Force Chief Loktionov, People’s Commissar of the Air Force Kaganovich. In principle, everyone was satisfied. But the decision was left to Stalin, by which developments in the field did not pass then aviation.
And Shevchenko got into a personal conversation with the leader, which took place after an extended meeting of workers in the aviation industry, where he received Stalin's formal permission to name the aircraft.
The aircraft IS-1 was an experimental one, built primarily to study and verify the mechanism for cleaning the wing and landing gear in flight. Although in the future weapons were planned for him. In the center wing of the upper wing, four ShKAS were located quite normally.
The lower wing consisted of a center section and folding consoles. The hydraulic mechanism in the fuselage turned the center section on the hinges of the fuselage fastening and folded the lower wing. The lifting mechanism consisted of a hydraulic cylinder and two rocker struts. A working pressure of 60 atmospheres was created by a pump mounted on the motor. Chassis and tail crutch were removed simultaneously with the wing cleaning. The crutch was removed by a cable mechanism.
I’ll draw your attention to the year 1938. The landing gear is retractable on several models, and on fighters this is done by rotating the handle of the cable mechanism. Here, except for the crutch, everything was done by hydraulics.
The chassis and crutch were equipped with shock absorbers, the wheels had brakes.
A separate masterpiece was the dashboard, consisting of three panels. The central panel had rubber anti-vibration dampers and a backlight, it housed all aerobatic and navigation devices.
On the right panel placed control of oxygen equipment and motor control. On the left are hydraulic warning lights, brakes, pressure gauges and magneto switches.
The plane caused a stir among test pilots. Not every day a car that a fellow pilot created has flown into the air. Lined up for those who want to fly on an airplane.
The first flight was carried out on May 29, 1940 by test pilot Vasily Kuleshov. Kuleshov made five flights, however, without removing the wing. They did not expect much from the car, since the M-25 engine was 635 hp. and could not give the car any outstanding performance characteristics. It was important to generally check the ability of the IS-1 to fly.
The wing was removed in flight on June 21, 1940, test pilot George Shiyanov. The plane behaved flawlessly, which simply struck Shiyanov, who wrote the following in his final report:
On take-off, the plane easily comes off and is not afraid of a side-view (side wind. - Approx. Author). Possible take-off with a blast (at the maximum angle of attack. - Approx. Aut.). At large angles of attack, there is no tendency to stall. The best set speed is 200-210 km / h. At a set speed of 240 km / h, a slight vibration of the tail feathering of the buffeting type is observed.
The plane is easy to fly and sits tight in the air. There is a slight shaking of the tail at low speeds. It turns steadily, but lack of engine power is felt. The forward view in the air is also insufficient. The device brought the speed to 300 km / h at an altitude of 2000 m. Plans IS-1 steadily, allows planning with abandoned rudders. Landing at landing at a speed of 190 km / h. But the review for landing is not enough.
Mileage is very stable. He made a landing with a crosswind of up to 45 m / s and a force of 10 m / s. The plane does not cause any doubts. ”
The famous pilot Stepan Suprun took part in the IS-1 flyby. IS-1 under the control of Suprun demonstrated both speed and high maneuverability. The pilot removed the wing and chassis immediately after takeoff. In his test report on IS-1, Suprun wrote:
In January 1941, a second aircraft, called the IS-2, was ready. This car was similar to the IS-1, but the engine installed the M-88 with a capacity of 950 hp.
A miracle did not happen, but it turned out just a wonderful car. Since the M-88 was a cut above the M-25, the IS-2 didn’t just fly. The horizontal speed reached 600 km / h, the smaller motor size made it possible to install two BSs instead of two ShKAS. That is, weapons have become very sane: two 12,7 mm machine guns and two 7,62 mm machine guns.
The mass of a second salvo is comparable to the Yak-1 or Me-109. LaGG-3 and MiG-3 (in the five-point version) were cooler, but these planes for other tasks were originally conceived.
In addition to a more powerful engine, the IS-2 has significantly reduced the midship of the fuselage, increased its elongation and made a more streamlined engine hood. The wing area is slightly reduced.
The IS-2 went through a test flight cycle, and that’s all. The war has begun.
Of course, with the outbreak of war, all work was stopped. IP turned out to be an expensive and technologically sophisticated fighter, which in wartime was not a virtue.
In addition, it turned out that, unfortunately, it is impossible to take advantage of the biplane in maneuver combat, since the wing and landing gear were removed synchronously. The advantages of the biplane were realized only on takeoff and landing.
Shevchenko did not give up and continued the struggle for the idea of his plane. There was a project of the IS-4 fighter with an M-71F engine with a capacity of 2000 hp.
Its estimated maximum speed near the ground was assumed at 660 km / h, and at an altitude of 6000 m - 720 km / h. The maximum calculated ceiling is 13 m. Armament was supposed to be made of 300 ShVAK guns, two at the root of the upper wing, two synchronous in the engine compartment.
The vessels were estimated by experts who had familiarized themselves with the project in 1944, and these were Joseph Lazarev and Nikolai Polikarpov, the aircraft could indeed show such parameters.
Compared to the first cars, the IS-4 had a more elaborate fuselage shape with a nose wheel instead of a tail crutch.
The niches in the sides of the fuselage for cleaning the wing and landing gear had to be closed with special automatically retractable walls, the landing gear was retracted into the center section regardless of the lower wing landing. Germocabin with a teardrop-shaped lantern.
Alas, the IS-4 was not interested in the Air Force either. The war was coming to an end, with it the era of propeller-driven aircraft was practically passing. All eyes were already directed toward jet aircraft. The last work of Shevchenko’s designer was the IS-14 aircraft, already jet, and also a new concept. But this is a completely different story.
Our story ends here. Shevchenko was not lucky. In 1938, our industry was not very ready to produce such a technically complex machine. And during the war, and even more so. Those LTH, which showed a plane assembled and licked at the Design Bureau, are not like the machine that the hands of women and adolescents would do in cold shops. And the results could only harm the designer.
This is not to say that Shevchenko worked in vain. This is generally a person who has lived a life with great benefit. 6000 hours of flight by a test pilot and a fighter pilot. In the war, designer Shevchenko again became a fighter, commander of a separate special squadron. 122 sorties.
Plus four flying sample aircraft, albeit not gone into the series. The idea did not sink into oblivion. The principle that Vladimir Shevchenko and his team of engineers worked on as part of Vasily Nikitin, Peter Nosikov, Vladimir Teplyakov, Nikolai Stolbovoy, Vsevolod Smirny, Anatoly Frolov, Viktor Abramov, Nikolai Tsigir, Evgeny Kolesnikov, Anatoly Andreyev, Tamara Reinvald, went further!
You can change the wing area in different ways. And today, looking at the photo of this funny Stalin-era aircraft, it is difficult to imagine the fact that the descendants of this aircraft are the MiG-23, MiG-31, Su-24, Tu-160.
And this is a fact.
LTX IS-2
Wingspan, m: 8,60.
Length, m: 7,36.
Height, m: 2,68.
Wing Area (full), sq. m: 20,83.
Weight, kg:
- empty aircraft: 1 400;
- maximum take-off: 2 180.
Engine: 1 x M-88 x 950 hp
Maximum speed, km / h: 588.
Cruising speed, km / h: 453.
Practical range, km: 600.
Practical ceiling, m: 10 800.
Crew, person: 1.
Armament:
- four 7,62 mm ShKAS machine guns or
- two 12,7 mm BS machine guns and two 7,62 mm ShKAS machine guns.
Information