The first one.......

Hi friends, now our topic is going to be about the first helicopter. In the 1930s, the French Louis Breguet and German Heinrich Focke had made major advances in helicopter design in Europe. A Russian who had emigrated to the United States, Igor Sikorsky, eventually made the most significant advances. Although Sikorsky is not generally credited with inventing any new solutions to the problems of controlling a helicopter in flight, he is widely regarded as the person who improved existing technology and made the helicopter practical and successful. Sikorsky Aircraft remains the oldest helicopter firm in the world.

Though already helicopter was invented by some other scientists, they don’t know how to stop the rotation of the helicopter’s body. They even used 2 counter rotating rotors, which solved the problem but increased its weight by 40%. Thus it failed…

Sikorsky's VS-300 was significant because it was the first working helicopter that did not require two counter-rotating rotors to cancel out torque, instead using a tail rotor that provided thrust in the opposite direction of the torque. This made the craft less complicated, lighter, and easier to control. But perhaps more importantly, the VS-300 served as the forerunner for the modern helicopter—it looked more like helicopters in use decades later than any of its predecessors. Unlike either Heinrich Focke or Louis Breguet, Sikorsky continued building helicopters and ultimately became the most famous helicopter manufacturer in the world.

About its construction…

• The VS-300 was constructed of an open welded tubular steel frame with three-wheel main landing gear.
• A three-bladed rotor with a diameter of 28 feet (8.5 meters) was mounted at the top.
• A single two-bladed vertical rotor was mounted at the tail. Both rotors were powered by a four-cylinder 75-horsepower (56-kilowatt) Lycoming air-cooled engine connected to the rotors through a truck transmission and a series of pulleys and belts.
• The main rotor could increase the pitch of the three blades collectively to change lift.
• Sikorsky also adopted cyclic control from Cierva's autogyro.