A helicopter is an aircraft with one or more power-driven horizontal propellers or rotors that enable it to take off and land vertically, to move in any direction, or to remain stationary in the air.
The idea of taking off vertically, making the transition to horizontal flight to the destination, and landing vertically has been for centuries the dream of inventors.
During the mid-1500s, Italian inventor and artist Leonardo Da Vinci (1452–1519) made drawings of an ornithopter flying machine, a fantastical machine that might have flapped its wings like a bird and that some experts say inspired the modern helicopter.
In 1784, French inventors named Launoy and Bienvenue demonstrated a toy to the French Academy that had a rotary-wing that could lift and fly. The toy proved the principle of helicopter flight.
In March 1923 Time Magazine reported Thomas Edison sent Dr. George de Bothezaat a congratulations for a successful helicopter test flight. Edison wrote, “So far as I know, you have produced the first successful
helicopter.” The helicopter was tested at McCook’s Field and remained airborne for 2 minutes and 45 seconds
at a height of 15 feet.
On 14 April 1924, Frenchman Étienne Oehmichen set the first helicopter world record recognized by the Fédération Aéronautique Internationale (FAI), flying his quadrotor helicopter 360 meters (1,180 ft). On 18 April 1924,
Pescara beat Oemichen’s record, flying for a distance of 736 meters (2,415 ft) (nearly 0.80 kilometers or .5 miles) in 4 minutes and 11 seconds (about 13 km/h or 8 mph), maintaining a height of 1.8 meters (6 feet). On 4 May, Oehmichen completed the first one-kilometer (0.62 mi) closed-circuit helicopter flight in 7 minutes 40 seconds with his No. 2 machine.
The Russian-American aviation pioneer Igor Sikorsky (1889–1972) is considered to be the “father” of helicopters, not because he was the first to invent it, but because he invented the first successful helicopter upon which
further designs were based.
On September 14, 1939, Igor Sikorsky flew his VS‑300, the first controllable helicopter.
In 1941, Sikorsky and Gluharaff designed the production model of VS300 and desinated VS316A . It was the bigger a bigger machine with an enclosed cabin and side by side seating and dual controls for two men crew 175 hp engine, a larger 36 ft (10.97 m.) rotor.The VS316A known by military designation XR-4 and YR4A.
After World War II the commercial use of helicopters developed rapidly in many roles, including fire fighting, police work, agricultural crop spraying, mosquito control, medical evacuation, and carrying mail and passengers.
During the closing years of the 20th century designers began working on helicopter noise reduction. Urban communities have often expressed great dislike of noisy aviation or noisy aircraft, and police and passenger
helicopters can be unpopular because of the sound. The redesigns followed the closure of some city heliports and government action to constrain flight paths in national parks and other places of natural beauty.
There are three basic flight conditions for a helicopter: hover, forward flight and the transition between the two.
The CH-47F Chinook is the world’s fastest helicopter, with a top speed of 315 km/h. The Chinook is a multi-mission military helicopter manufactured by Boeing Defense, Space & Security.
In terms of rotor length, the smallest helicopter is the GEN H-4 made by Gen Corporation (Japan) with a rotor length of only 4 m (13 ft), a weight of only 70 kg (154.32 lbs), and consisting of one seat, one landing gear and one power unit. Unlike more traditional helicopters, it has two sets of coaxial contra-rotating rotors which eliminate the need for a tail rotor for balancing.
Helicopters cost between $1.2 million and $15 million, depending on the size and type of machine.
The cost for a proposed fleet of 28 VH71 Kestrel helicopters was estimated at a record $13.2 billion (£8.7 billion), making it the most expensive helicopter in the world. The programme was stopped in February 2009 for the re-evaluation of different cost options.
The English word “helicopter” is adapted from the French word hélicoptère, coined by Gustave Ponton d’Amécourt in 1861, which originates from the Greek helix (ἕλιξ) “helix, spiral, whirl, convolution” and pteron (πτερόν) “wing”. For various reasons, the word is often erroneously, from an etymological point of view, analysed by English speakers into heli- and copter, leading to words like helipad and quadcopter. English language
nicknames for “helicopter” include “chopper”, “copter”, “heli”, and “whirlybird”. In the United States military, the common slang is “helo” pronounced with a long “e”.