The helicopter, always associated with vertical take-off and connected to rotation, is a type of aircraft. It is heavier than air, can take off and land vertically, hanging in the air, moving in all directions. The required lifting power and thrust are generated by one or several motor-driven propellers. A counter system (generally tail screw) prevents uncontrollable giration and the rotor gear serves to balance torque and control the aircraft. Origin The term "helicopter" came from 2 ancient Greek words: helix (ἕlix) - "something twisted, rotated, spiralled", and pteron (wing). The word helicopter was introduced as a concept and adapted in French by Gustave Ponton d'Amécourt in 1861.
The first proven historical document with the idea of a flying contraption is a Chinese painting from the 4th century BC. On it are depicted children holding a toy using a helicopter-like giration principle.
In the 2nd century BC Archimedes of Syracuse create an experienced system with propellers spinning under the influence of sunlight.
The earliest known drawing of a helicopter was made by Leonardo da Vinci in 1483. A model was created on the drawing, which is currently in the Natural History Museum in London.
The first helicopter patent was registered in England in 1859 by Henry Bright. It consists of 2 oppositely rotating axial screws, one on top of which the propellers are attached. In the middle of the 19th century, such a machine could not fly because of the lack of a suitable energy source. Steam was then way too heavy for that purpose.
The earliest helicopter flight was made in 1907 by French Dewey. A short while later, rothers Louis and Jacques Breguet created a gyroplane with an engine driving four independent screws. The flight was controllable only by the means of 4 ropes held by aides to maintain the balance of the machine. The flight took about 1 minute, reaching 60 cm above ground.
The first free, controlled, helicopter vertical flight with no land connection was conducted by Frenchman Paul Cornu on September 13, 1907. A year later, in 1908, the Breguet brothers created a new helicopter model with a Renault 55 hp engine and two counter-rotating screws. The flight took place on July 22, 1908, reaching 4.5 m in height.
In 1939, Russian immigrant and aviation engineer Igor Sikorski constructed a prototype of the modern helicopter, the Vought-Sikorsky 300, with a closed cockpit, modern three-blade propeller and 75 hp engine. The first of the 3 successful flights took place on May 26, 1940. This model was produced at the end of the war and the only one used operationally (with the German Flettner). The postwar golden age The development of the helicopters goes through several stages, depending on the fitting of more perfect engines, electronic equipment and the use of different units and aggregates can be divided into several generations.
First generation helicopters appeared in the 1950s. They are fitted with piston engines, develop a low speed, low load capacity and a small field distance. The following models can be included in this generation: S-51, S-58, HTK-1, Bell-47, HSL-1, Mi-1, Mi-4, Ka-10, Ka-18 and others.
Second-generation helicopters appeared in the 1960s. They are equipped with turbocharged gas turbine engines, allowing a significant increase in their capacity and improved flight characteristics. They have a sophisticated design of the bearing and tail screws, an automatic in-flight stabilization system is used. This generation includes Bell 204, Bell 205, Bell 206 and Bell 209 helicopters. Sikorsky S-16, Sikorsky S-26, Sikorsky S-64 and Sikorsky S-65, Kaman HH-43, UH-2, Hiller OH-5, OH-6, Ka-22, Ka-25 and Ka-26, Mi-2, Mi-6, Mi-8, Mi-10 and others.
Third-generation helicopters appeared in the early 1970s. They have a sophisticated overall design, improved aerodynamic qualities, completely new electrical equipment and high economy. This generation includes the Bell-222 and Bell-230, McDonnell Duglas AH-64, Bo-105, Sikorsky S-70, Aérospatiale SA 330 Puma, Dolphin, Lynx, Mi-24, Ka-23 and others.
Fourth generation helicopters appeared in the mid-1970s. The use of composite materials is widely used, advanced electrical equipment is installed, allowing them to operate in complex weather conditions and at night. This generation includes the EC-120, S-76S +, Ka-27, Ka-29, Ka-31, Ka-32, Mi-26 and Mi-34 models.
Fifth-generation helicopters appeared in the early 1990s. They are fully computerized, using multifunctional displays, advanced flight control systems and a digital engine management system. Models: RAH-66, EH-101, NH-90, Ec-135, Eurocopter Tiger, Mi-38, Mi-46, Ka-50, Ka-62, Ka-226 and many others.