The helicopter was created at the same time as the aircraft, and for a long time these machines were competitors. However, in the second decade of the XX century. it became obvious that a helicopter can solve completely different tasks: take off from a place without a preliminary takeoff and land on a very small platform, hang motionless in the air, move progressively in all directions.

The prototype of helicopters was invented by the Italian artist and inventor Leonardo da Vinci, who in 1480 painted an aircraft with a huge propeller. Three hundred years later, the Russian scientist Mikhail Lomonosov demonstrated a model of an "air-running machine" with two screws driven by clockwork. In 1877 the Italian physician Carlo Forlanini and the Frenchman Gustave de Ponton d'Amecourt tried to make models of helicopters with a steam engine.

By the beginning of the XX century. the internal combustion engine appeared. It was he who was installed on an aircraft called a gyroplane, created by French engineers Louis and Jacques Breguet in 1907. The gyroplane, held by ropes, rose 60 cm into the air and stayed above the ground for a minute. In the same year, the French cycling designer Paul Cornu performed the first free flight on a vehicle of his own design, which lasted only 20 seconds. with a lifting height of less than 2 m.

There were other inventors who created various designs with a complex multi-screw circuit. The scheme of a helicopter with one rotor, which later became classical, was published in 1911 by Russian engineer Boris Yuriev. He also invented the swashplate, a mechanism still used in modern cars. But Yuryev did not have the money to build a helicopter. Three years later, English engineer Edwin Mumford made the first forward flight in his helicopter.

Further development of technology and the study of the aerodynamics of rotorcraft made it possible to achieve serious success. Helicopters began to move in any direction, perform turns and turns on the spot. There were models capable of making long-distance safe flights at high altitudes. Such models were "Breguet-Doran" in France and "Focke-Wulf" in Germany. They were twin-rotor helicopters of a transverse design and were so successful that the transverse design attracted the attention of designers for a long time.

Nevertheless, a single-rotor scheme was gradually established in helicopter construction. This happened thanks to the American aircraft designer Igor Sikorsky, who improved the classic Yuriev scheme. In 1942, the Sikorsky helicopter was adopted by the US Army and put into mass production. A year later, the British Royal Navy acquired a more powerful model, the Si-Kor R-4.

During the Korean War (1950-53), the helicopter was used for the delivery of troops and the removal of the wounded, and during the Vietnam War (1954-75) - as air artillery.

Helicopter Heinrich Focke (late 1930s) had two three-bladed rotors and a pulling propeller, which allowed a horizontal speed of over 120 km / h. This helicopter set a world record for a flight duration of -1 hour and 20 minutes.

Who is who in the world of discoveries and inventions Sitnikov Vitaly Pavlovich

Who Invented the Helicopter?

Who Invented the Helicopter?

The dream of an aircraft that could take off into the air arose a long time ago. Leonardo da Vinci already in 1500 AD drew a drawing of a huge propeller-shaped helicopter. But he never tried to build a helicopter because he didn't have an engine. In 1783, a toy helicopter known as the "Chinese spinning top" was shown in France. It is still unknown who invented it. In 1796 Sir John Keighley made prototypes of Chinese spinning tops and also designed a helicopter that was powered by steam.

Over the next 100 years, many people were involved in the construction of helicopters. Some of these models were fantastically complex, some were simple, but only a few of them could fly. The hardest part was that there were no powerful yet light engines. Such an engine was made only during the First World War. He allowed the construction of a helicopter that took off from the ground with a man on board.

In 1909 and 1910, Igor Sikorsky designed two helicopters. One of them could lift his own weight. In late 1917, two Austro-Hungarian officers designed a helicopter to replace the observation tethered balloon. He made several take-offs to great heights, but this helicopter could not be freely maneuvered.

Work on helicopters continued in many countries. But none of the cars met the expectations of the designers.

In 1936, a message came from Germany that a successful helicopter design had been made by the Focke-Wulf company. In 1937, he flew over the entire country at a speed of about 70 miles per hour and at an altitude of over 335 meters.

In 1940, Sikorsky demonstrated his first operational helicopter. This helicopter was adopted by the US Army in 1942.

For the first time, real prerequisites for the transition from the prior experimental modeling of helicopters to the construction of special purpose vehicles appeared at the end of the 30s of the twentieth century. Similar technologies developed in the Soviet Union, but the Great Patriotic War stood up to the introduction of the ideas of building helicopters, which made adjustments not only to the public life of the state, but also to the development of science and, in particular, helicopter construction. But nevertheless, despite the extremely difficult situation in the country, Professor B.N. Yuriev was able to organize the first specialized enterprise, the main purpose of which was the modeling and construction of a completely new type of aircraft - helicopters.

On December 17, 1939, on the basis of the order of the People's Commissariat of the Aviation Industry of the USSR, an independent OKB-3 was created, and already on March 4, 1939, B.N. Yuriev and I.P. Bratukhin were tasked with building the first two-seater helicopter with two MV-6 engines , with a flight range of at least 200 kilometers and a speed of 150 km / h. The order indicated the need to build two such air vehicles, and also indicated the timing of the provision of helicopters for testing. The first car was to be delivered no later than May 1, 1941, and the second two months later, on July 1, 1941.

In the early spring of 1940, due to the high employment at another facility, B.N. Yuriev completely transferred the affairs of the creation of helicopters to his colleague I.P. Bratukhin. In May 1940, the design bureau presented the first model of the future helicopter. The transverse scheme was chosen as the main supporting structure, the expediency of which at that time was doubted by many builders of aviation equipment. Perhaps Bratukhin's idea was prompted by the successful work of German designers who created and successfully tested their FW.61 helicopter.

The first helicopter project was codenamed "Omega". In connection with the outbreak of the Great Patriotic War, the construction time of the first air vehicle was shifted, and only in August 1941, the Omega was transferred for testing. The length of the helicopter was 8.2 meters, the diameter of the main rotor was 7 meters. Because of the war, it was decided to evacuate OKB-3 to Alma-Ata, which was the reason for stopping work on the project for almost two years.

Despite the fact that on August 27, 1942, by order of the People's Commissar of the Aviation Industry, a test pilot was appointed, who became the engineer of the LII DI Saveliev, the first flight took place much later. The first tests were fully reported on June 24, 1943. In particular, this report described all stages of test flights, and gave a full description of the technical capabilities of the created helicopter.

According to the report, the takeoff weight of the helicopter was 1,900 kilograms, and the maximum speed was 186 km / h. The tests were carried out in extremely harsh meteorological conditions. The air temperature was +50 degrees, which significantly reduced the power of the engines. The MV-6 engines were air-cooled and quickly overheated due to the heat. The flight duration did not exceed 15 minutes, and the flight speed was 115 km / h at an altitude of 150 meters. This, of course, was less than the indicators of the first test flight and the planned parameters.

Nevertheless, a positive effect was achieved during test flights. Firstly, the created machine was fully operational, and, secondly, confirmation of its stability was obtained. The main problem was the use of low-power MV-6 engines, which could not provide the necessary power for the full operation of the helicopter.

For the manufacture of the Omega fuselage, a truss structure was chosen, which was welded from steel pipes and sheathed with percale. In the nose of the helicopter there were two seats for the pilot and the observer. The propeller blades had a diameter of 7 meters and were made of an all-metal structure. As the balancing of the aircraft in horizontal flight, a structure was chosen, consisting of a keel with a rudder and a T-shaped strut-braced adjustable stabilizer. The entire structure was a tail unit.

To control the helicopter in the longitudinal and cross sections, a handle was used, with which the pilot tilted the rotor thrust vector together with changing the differential and cyclic pitch. For directional control, pedals associated with the rudder were installed. The installed steering wheel served to deflect the stabilizer.

Factory tests were carried out until 1944. During this time, significant changes were made to the design of the "Omega". In particular, the low-power MV-6 engines were replaced by MG-31F, which differ not only in higher power, but also surpassed the previous power units in terms of reliability. Changes were also made to the design of the side trusses, which made it possible to increase the flight weight to 2900 kilograms. The new design was named "Omega-2", and by the end of 1944, factory tests were carried out. One of the reasons why the transfer of the air machine to mass production was delayed was the presence of significant vibrations. Attempts were made to install special dampers, but they only reduced the vibration level, but it was not possible to remove it completely.

But, despite some shortcomings, the car was practically ready to perform various tasks, and the appearance of "Omega-2" in service with the Soviet Army was a matter of time. And there was no doubt that the army needed such equipment.

On January 13, 1942, Sikorsky's helicopter took off for the first time - the world's first helicopter designed for military purposes. The scientist-aircraft designer Igor Sikorsky began the development of helicopters in pre-revolutionary Russia, and realized them already while in exile in the United States. Today, in our review, a dozen of the most famous military helicopters.

Light multipurpose helicopter Sikorsky R-4 "Hoverfly"

The first Sikorsky helicopter VS-300 took off back in 1939. The designer personally piloted the car. The VS-300 had a completely primitive appearance, and the fuselage did not even have a skin. The pilot sat in a small seat completely open, right in front of the engine. Initially, the helicopter was powered by a 65 horsepower Lycoming engine that propelled a three-blade propeller. The helicopter was heavy to fly, vibrated strongly and stayed in the air for only a few seconds.

Sikorsky continued his development and in January 1942 presented the R-4 "Hoverfly" helicopter. The helicopter could reach speeds of up to 120 km / h and fly 180 km, climbing with one pilot to an altitude of 3650 meters (2800 meters with two pilots). The mission of the first military helicopter is communications and rescue operations. The Sikorsky R-4 "Hoverfly" has been in service with the United States since 1942 and since 1945 in service with the UK. Military aircraft operated this helicopter in Alaska and during the Burma War, where the R-4 supported the advancement of American forces in the jungle, delivering cargo and messages and evacuating the wounded. The R-4 was retired from service in the late 1940s.

The first Soviet serial helicopter was the MI-1. In flight and technical characteristics, the Mi-1 resembled the famous American Sikorsky S-51 helicopter (1949). But if the American helicopter was produced in a small series and was not built for a long time, then the Mi-1 helicopters were widely used in the national economy and in the armed forces of the USSR, as well as other countries where the helicopter was exported.

Since 1954, Mi-1 helicopters have been produced in Orenburg, later in Rostov, and since 1957 they have been produced under license in Poland. In total, more than 2.5 thousand Mi-2 helicopters were built. In the period from 1958 to 1968, 27 international records were set on this helicopter, including a speed record (141.392 km / h), an altitude record (6700 m) and a flight range (1654.571 km). Mi-1 is still in operation in many countries of the world.

Mi-8 is the most popular helicopter in the world

The Mi-8 helicopter was put into production in 1965. The history of this machine began in 1958, when Nikita Khrushchev summoned designer Mikhail Mil to the Kremlin and offered to go to the United States to purchase several helicopters from Sikorsky's company, and most importantly, to inspect the production and find out the capabilities of American machines.

The Mi-8 helicopter was equipped with two 1500-horsepower engines with a 12-stage compressor, an annular direct-flow combustion chamber and a 2-stage axial turbine. In the event of a failure of one of the engines, the other automatically went to increased power, due to which the machine performed vertical flight without lowering the altitude. In addition to 3 crew members, the helicopter could take on board 24 paratroopers or 28 passengers and transfer them to a distance of up to 425 km at a cruising speed of 225 km / h. The maximum speed of the Mi-8 is 250 km / h.

In June 1965, the USSR presented the Mi-8 at the international air show in Le Bourget, and the helicopter became a real sensation.

Over 50 years of the aircraft's existence, more than 12 thousand Mi-8s of various modifications have been produced. The latest military modification of this helicopter, the Mi-8AMTSh "Terminator", is designed to combat armored surface, ground, mobile and stationary small targets, to transport troops, military cargo, wounded, to defeat enemy personnel, as well as for evacuation and search operations. rescue work.

In November 1986, the Soviet Ka-31 helicopter took off, which has no analogues in the world helicopter industry. Its main feature is the ability to conduct a radar patrol. The helicopter can be based on ships, or it can be used in a land-based version to solve air defense missions for ground forces.

A radio-electronic complex is installed on board the Ka-31, which makes it possible to conduct an automated helicopter flight in any climatic and weather conditions along a programmed route, detect and take up to 20 targets for auto-tracking. At the same time, the helicopter transmits information about the targets to the control points via the telecode communication channel.

The helicopter today has no analogues in terms of its combat characteristics. It is capable of detecting air targets of the "airplane-helicopter" type at distant lines at extremely low flight altitudes. The helicopter is also used for the detection of surface ships and their escort. The ship-based Ka-31 helicopter is capable of protecting formations of warships from air strikes, which operate outside the zone of AWACS aircraft and coastal radars. The Ka-31 is currently in service with the Russian Federation and India.

Ka-50 "Black Shark"

The Soviet Ka-50 helicopter, a prototype of which took to the air in the summer of 1982, became the world's first helicopter with an ejection seat, providing the rescue of a pilot in any flight mode. The safety of the pilot in this car was given a special place: the cockpit is fully armored using spaced metal plates, the total weight of which exceeds 300 kg. Tests have shown that the protection of the pilot is guaranteed when 12.7 mm bullets and fragments of 20 mm shells hit the side of the vehicle.

The tests of this helicopter were kept in the strictest confidence. They were tested not far from Moscow, in full view of many curious people. Therefore, the OKB specialists went for original camouflage measures: the combat vehicle was turned into a transport vehicle, additional windows and doors were painted on the sides of the fuselage with bright yellow paint.

The first baptism of fire of the Ka-50 helicopter took place during the anti-terrorist operation of the Russian army in Chechnya in January 2001. The vehicle is capable of performing combat missions in the most difficult mountain conditions, demonstrating its power-to-weight ratio and maneuverability in battle.

The Mi-26 is the world's largest multipurpose transport helicopter used in both civil and military aviation. The first Mi-26 took off in 1977. Today, the helicopter, nicknamed the "flying cow" by the pilots, is the largest helicopter in the world. It is capable of lifting up to 20 tons of cargo into the air, and not only on board, but also on an external sling. For heavy loads, a winch is provided that can lift loads up to 500 kg. The helicopter can accommodate 82 paratroopers or 60 stretchers with the wounded. The maximum speed of the car is 295 km / h.

Sikorsky UH-60 "Black Hawk"

The helicopter of the XXI century is considered by many to be the Sikorsky UH-60 "Black Hawk" helicopter, created 40 years ago. With a carrying capacity of 1500 kg on board or up to 4000 kg on an external sling, he takes on board 14 fighters. Today there is a basic land version of the UH-60 and 2 anti-submarine versions - SH-60F Ocean Hawk and SH-60B Sea Hawk. There is also a line of deck helicopters, fire support helicopters, special operations vehicles, ambulance versions and jammers. The Sikorsky UH-60 is used as a command helicopter for generals and high-ranking officials. Today this helicopter is actively exported.

Attack helicopter Boeing AH-64 "Apache"

The iconic Apache helicopter gained fame in Operation Desert Storm, where, according to NATO officials, it successfully fought tanks, and became the prototype for a whole class of modern combat helicopters. This helicopter is regularly used by the IDF Air Force. The helicopter is equipped with 16 Hellfire anti-tank missiles, Stinger missile systems for air combat and a 30 mm built-in automatic cannon.

Experts say that today the Russian Mi-28N Night Hunter has thrown an open challenge to the Apache in flight performance characteristics. And in 2002, an export version of the Mi-24 with modern avionics of the DPRK Air Force shot down the South Korean Apache from an ambush. South Korea admitted the loss and demanded that the United States hold a free park of its "Apaches". The dispute has not yet been resolved. American helicopters even became a source of inspiration for the designers who created the collection.

"Huey" (Iroquois) - a symbol of the Vietnam War

The Huey helicopter, along with napalm, has become a symbol of the Vietnam War. These helicopters were "home" for the American military - they delivered them to positions, supplied them with provisions and ammunition, brought up equipment and evacuated them from the battlefield.

According to statistics, over the 11 years of the war, the Huey flew 36 million sorties. If we take into account that 3 thousand vehicles did not return to the base, it turns out that for 18 thousand sorties there was 1 irrecoverable loss. The result is unique! And this despite the fact that the "Huey" had no reservation at all.

Mi-24 "Crocodile" - hybrid helicopter

Mi-24 is a Soviet combat transport helicopter, the first flight of which took place in 1969. In NATO, he received the code name "Doe" (Hind), and the American experts passed the verdict: the Mi-24 is not a helicopter.

Although outwardly the Mi-24 looks like a helicopter and is used like a helicopter, from a technical point of view, it is a hybrid. He cannot take off from a "patch". Its visually disproportionately large pylons are actually wings. The Mi-24 was designed as a “flying infantry fighting vehicle”. And the designers managed to turn the heavy armored helicopter into one of the fastest combat helicopters in the world (it can reach speeds of up to 320 km / h).

"Crocodile" took part in hostilities in the Pamir Mountains, in the gorges of the Caucasus, in the tropical forests of Equatorial Africa and in the sultry Asian deserts. Fighting glory came to him in Afghanistan. This unique rotary-wing attack aircraft became a symbol of that war. One of the Afghan mujahideen in an interview with the American news channel about "Crocodile" said: "We are not afraid of the Russians, but we are afraid of their helicopters." The Mi-24 is the only helicopter in the world to shoot down a combat aircraft in an aerial battle (F-4 Phantom fighter)

The outstanding aircraft designer Igor Ivanovich Sikorsky (1889-1972), who is rightfully considered the founder of the world helicopter industry, was born on May 25 (June 6), 1889 in the family of the famous Kiev scientist and public figure, psychiatrist, professor Ivan Alekseevich Sikorsky. The role of parents in the upbringing and development of a son can hardly be overestimated. It was from the mother of Maria Stefanovna that little Igor first heard about the helicopter. She was fond of the work of Leonardo da Vinci and told her son about the car designed by the great Italian. Igor's favorite book was Jules Verne's novel Robur the Conqueror, which described a journey around the world in an airship-helicopter. Sikorsky recalled that when he was eleven years old, he saw in a dream a flight on such a flying giant. In this dream, the dream and purpose of his whole life came true.

I.I. Sikorsky in the presidential helicopter S-61 in 1962

V.R. Mikheev, Cand. tech. Sci., Institute of the History of Natural Science, RAS

Like all future aircraft designers, Igor began by building flying models. At the age of 12, he built the first rubber-powered helicopter. Several more models followed. Their sizes were constantly increasing. Training workshops of the Naval Cadet Corps in St. Petersburg, in which in 1903-1906. Sikorsky was trained, they were allowed to make models of any type. In 1906-1907. Igor studied at the Parisian technical school Duvignau de Lanneau. A stay in Paris, then the capital of aviation, strengthened the young enthusiast in the correctness of the chosen path. Having become a student of the Kiev Polytechnic Institute in 1907, Sikorsky joined the student aeronautical circle and was an active member of the "Helicopter" section. Many Kiev aviators (including one of Sikorsky's teachers, professor at the Polytechnic Institute, Professor N.A. Artemiev) were fond of developing rotary-wing aircraft at that time.

Igor Sikorsky made the decision to start building a full-scale helicopter in the summer of 1908 while staying with his father in Germany. Right in the hotel room, he built a stand to determine the lift of the rotors. A propeller with a diameter of 1 m 20 cm, assembled from wooden planks, was installed on some kind of scales that measure the pulling force. The moment required for spinning the screw was created by a load tied to a string, the other end of which was pulled through the block and wound on the screw axis. The power was determined by the movement of the load. Sikorsky took the improvised stand to Kiev, where he continued his research in his home workshop. The experimenter received a lifting force of over 36 kg per horsepower. He understood that it would not be possible to obtain such results on a full-scale helicopter, but still considered it possible to achieve success. Confidence grew stronger after a meeting at the end of 1908 with the "father of Russian aviation" Professor N.Ye. Zhukovsky, who always favored the idea of ​​a helicopter. The professor came to Kiev to give a lecture "Achievements of Aeronautics", during which he launched models of aircraft into the hall. Young Sikorsky was lucky to catch one of them.

Helicopter N1 after assembly. July 1909

For the construction of the helicopter, an engine and a number of other parts were required, which were difficult to get in Kiev. Igor turned to his family with a request to let him go to Paris to purchase the necessary things and get acquainted with the latest achievements of aviation. This request did not arouse enthusiasm among the relatives. The fact is that the young talent completely launched his studies at the institute. In addition, Paris was considered a cheerful and frivolous city, and it would be unreasonable to let a nineteen-year-old boy go there, and even with a large amount of money. And nevertheless, Sikorsky managed to convince his relatives, to receive a parental blessing and the necessary money for purchases, which his older sister allocated to him. In January 1909, the young enthusiast left for Paris. Here he managed to get acquainted with F. Ferber, L. Bleriot and S.K. Drzewiecki - the patriarchs of world aviation. They were skeptical about the idea of ​​a helicopter, but this did not stop Sikorsky. He purchased a 25 hp Anzani engine. and a number of parts for the future helicopter, including coaxial shafts and other transmission elements. His contacts with French aviators after this trip became permanent.

After more than three months' absence, on May 1, 1909, Igor returned to Kiev and began building a helicopter. In the garden of the Sikorskys' house on Podvalnaya Street (now Yaroslavov Val) there was a small one-room gazebo house. He became the first aircraft manufacturer of the designer. The student M.F. Klimikseev (son of the Sikorsky housekeeper) and a hired carpenter. In July 1909, the construction of the first Sikorsky aircraft was basically completed.

For the helicopter, Igor chose the structurally simplest and well-tested two-screw coaxial scheme on the models. At that time, the diameters of the coaxial rotors were usually made different (the diameter of the upper rotor was 4.6 m, and the lower - 5 m). This was done to reduce the harmful effect on the blades of the lower rotor, which arose from the blowing of the upper rotor flow. The screws rotated in opposite directions with a frequency of 160 rpm.

The empty weight of the helicopter was 205 kg. The apparatus was arranged as follows: in front of the shafts of the propellers and the gearbox, right on the floor, with an axis across the flight, was the engine, and in the back was the pilot's seat. Two concentric vertical shafts rose above the gearbox and passed through bearings at the top of the fuselage. The fuselage was a rectangular cage braced with a piano wire. Its uprights were made of steel pipes, and the crossbars were made of wooden blocks.

Two-blade rotors were attached to steel shafts. The power base of each blade was two wooden spars converging crosswise over each other at the attachment point on the main shaft. The angle between them determined the twist of the blades. To the spars were attached rectangular blades of small elongation, which had a metal frame and were covered with fabric. The blades were braced with a piano wire to two annular couplings mounted on each shaft above and below the bushings for each propeller. By changing the wire tension with these couplings, it was possible to adjust the pitch of the rotors. Due to this, it was assumed in the future to control the magnitude of the lift and directional control of the helicopter. For longitudinal-lateral control and translational movement, it was envisaged to use control surfaces - rudders located in the inductive air flow thrown by the rotors. Their installation was supposed only after checking the reliability of the parts of the structure and achieving the necessary lift for takeoff.

The power of the Anzani engine, as it often happened with the motors of this company, turned out not to be 25 hp, as indicated in the passport, but only 18. A flywheel was installed on the output shaft of the engine for smooth running. Behind the flywheel was a pulley from which power was transmitted via a four-inch belt to the input pulley of the gearbox. To reduce the speed, the second pulley was made of a much larger diameter. The gearbox had a coaxial design, classical for helicopters - the connection of three bevel gears. Oil and fuel tanks were located above the engine. During the tests, the fuel tank was removed, and fuel was fed through a hose to the engine directly from the canisters. The helicopter did not have a chassis as such. It was installed on a two-wheeled wheelbarrow, with the help of which the device could be transported along the rails laid in the garden from the gazebo to the test site.

Drawing of helicopter N1 from the newspaper "Kievskaya Iskra" from 17.09.1909. Additional consoles are visible to increase the rigidity of the blades in the plane of rotation

This is a historic moment. Igor Sikorsky took the pilot's seat, started the engine and began to slowly increase the speed. But the screws didn't turn. The belt slid over the pulleys and did not transmit torque. When the defect was repaired with the pressure roller and the screws were able to rotate, strong vibration occurred. I had to remove the blades and balance them carefully. In addition, the rigidity of the blades in the plane of rotation was significantly increased due to their reinforced bracing to the additional transverse consoles added to the bushings of the upper side members. Vibration has decreased. The rotation mode became softer, but when the revs increased, there was a shaking again. For the first time, the young designer met with the problem of tuning out resonances and reducing vibrations, which is so typical for rotary-wing aircraft. He made the correct conclusion: the reason for the resonance was the insufficient stiffness of the upper rotor shaft. To calculate the resonant frequency, he climbed to the top of the cage, and, exciting the vibrations of the shaft with his hand, determined that the frequency corresponds to 120 vibrations per minute. Fixing the defect was just as easy. Sikorsky picked up a wooden rod 1.2 m long and began to drive it gradually into the hollow shaft of the screw, from time to time measuring the frequency of its oscillations. When the lower end of the rod reached the position of the upper bearing, the natural frequency began to increase sharply. The designer continued to hammer the rod until the frequency reached 175, i.e. became higher than the maximum values ​​of the range of operating rotational speeds of the rotor. The resonance stopped. The experience of solving the problems of dynamic strength was subsequently very useful to Sikorsky when fine-tuning other aircraft, in particular, the Russian Knight.

Now it was possible to bring the engine to full power. Igor, staying on the ground outside the cage, gave full throttle. The helicopter, unbalanced by the weight of the pilot, began to tip over towards the heavy engine. The designer stopped the engine and jumped onto the raised part of the cage floor. The apparatus slowly returned to its original position under its weight. The helicopter was saved. Many years later, Sikorsky described his impressions in the following way: “For the first time then I felt the power of the machine, and the helicopter, as it seemed to me, demonstrated its readiness to soar into the air. I remember exactly how I felt. When I stood on the floor, the end I was on did not go down, but was resisted by some force supporting it from below. "

After the appropriate weight rebalancing, Sikorsky continued testing. The engine roared at full power, but the helicopter did not rise, but only rotated on the ground - "waltzing". To balance the machine with respect to the vertical axis, the differential total pitch of the screws had to be carefully adjusted. Once, with a strong gust of wind, there was a danger of overturning to one side. This confirmed the need to install an effective longitudinal-lateral control. The designer considered the previously assumed control by means of surfaces in an inductive flux inappropriate due to the insufficient power of the flux revealed during the tests.

After eliminating all the shortcomings, Sikorsky saw that with a full gas supply, the screws take on most of the weight of the machine, but they still cannot take it off the ground. It was obvious that this machine with a man on board could not climb. Igor changed the test program. He made a large scale to measure the lift of a helicopter. The scales made it possible to determine that the thrust of the propellers corresponds to approximately 160 kg, which is 45 kg less than the weight of an empty car. The designer concluded that it was necessary to lighten the design, increase the rotor diameters and improve the aerodynamics of the blades. Experiments with the first helicopter were completed in October 1909 after a series of tests of propellers of various designs. On November 18-19, 1909, Sikorsky's helicopter was successfully demonstrated at the Aeronautical Exhibition in Kiev, held by the Kiev Aeronautics Society, and was recognized as the "highlight of the exposition".

3 projections of the N1 helicopter

Although the first Sikorsky helicopter did not manage to take off, the designer gained a lot of practical experience during his tests, which is especially important for the further design of propellers. Subsequently, experiments with the models showed that they flew significantly better than those with which the designer experimented before the construction of the helicopter. Many Kiev aircraft manufacturers began to order propellers for their aircraft not in France, as before, but from the student Sikorsky.

What is the role of the first aircraft of an aircraft designer in the world and Russian helicopter industry? Of the four dozen helicopters built by the end of 1909, only five machines managed to get off the ground. In 1907, the first to fly off the ground were the rotorcraft of the French inventors L. Breguet and P. Cornu. They briefly took to the air with a pilot on board. Two other helicopters, the Englishman G. Wright and the American W. English, took off in 1908 and 1909. no payload. All of them had an aerodynamically advantageous design with rotors located side by side in the same plane. At that time, almost half of the helicopters built had, like the Sikorsky apparatus, a coaxial scheme - structurally simpler and more compact, but energetically unfavorable due to losses from the mutual influence of the rotors. Of the coaxial helicopters, only the rotorcraft of the American designer J. Williams managed to get off the ground. This happened in 1908. The success was achieved largely thanks to the installation of special engines on the helicopter - light, but unreliable. As you can see, the results obtained by Sikorsky fit well into the overall picture of the achievements of that time.

In Russia, attempts to build full-scale helicopters have been undertaken by many enthusiasts since the 80s-90s of the 19th century. They were B.D. Potemkin, P.D. Kuzminsky, D.K. Chernov, S.A. Grokhovsky, then I.I. Lipkovsky, S.O. Oshchevsky-Kruglik, Ch. Tansky and others. In 1908-1909, in addition to Sikorsky, Russian inventors V.V. Tatarinov, K.A. Antonov, N.I. Sorokin, V.N. Levitsky, A.F. Simonov, K.E. Freezing. For various reasons, all these works were delayed. By 1909, not a single engine-equipped helicopter had been completed. Only Sikorsky, the first among Russian helicopter designers, managed to complete the work and conduct full tests of his ma tires

Igor Ivanovich Sikorsky (25.05.1889-26.10.1972)

I.I. Sikorsky was born in Kiev, completed the general course of the Naval Cadet Corps and received an aviation engineer diploma from the St. Petersburg Polytechnic Institute.

After successfully participating in the Moscow Aeronautical Exhibition and the Aeronautical Congress at the Polytechnic Museum in 1912, he received the position of chief designer at the Russian-Baltic Carriage Works in St. Petersburg, and also served for some time as chief engineer of the naval aviation.

Sikorsky was the first in Russia to create a helicopter capable of taking off; the multi-engine giants "Russian Vityaz" and "Ilya Muromets" that had no analogues in world practice, as well as serial reconnaissance aircraft and fighters; designed: water-cooled aircraft engine; founded a number of large aircraft factories, as well as civil and military schools for the training of flight and ground aviation personnel. With the active participation of the aircraft designer, the world's first strategic aviation unit was formed.

In 1918 I.I. Sikorsky was forced to leave Russia. Together with other exiles, in 1923 he founded a company in the United States, which soon became one of the leaders in the naval aircraft industry. The designer's airliners were the first to open regular transoceanic passenger traffic.

During the Second World War, Sikorsky created the world's first operational helicopters of the classic single-rotor design. With their release, helicopter construction began in the USA, Great Britain, France and some other countries of the world.

Sikorsky was awarded over 80 high state and scientific awards and prizes, many famous universities have chosen him as their professor. Sikorsky became famous not only for his numerous works on various issues of aircraft construction, but also for a number of publications on theology and philosophy.