8/3/2019 Supported in Flight by the Reactions of the Air on One or More Rotors

1/2

supported in flight by the reactions of the air on one or more rotors

In remote areas, there will be no airstrips; in wartime, runways areconspicuoustargets, and, with the exception of the aircraft carrier, are xed. Thehelicopters ability

to hover means that it can land almost anywhere a fairly at rm surface exists.

History

1 In 15th century Italy, famous artist and inventor Leonardo da Vinci (1452 - 1519) produced this sketch of a "helical air screw" to be powered by a wound-up spring. Although this device, with its rotating spiral toprovide lift, was never built - it is one of the earliest drawings of a helicopter machine.

2. Ukranian engineer Igor Sikorsky (1889 - 1972) is credited with building the world's first helicopter in1909, but it was more than 25 years before early practical machines - like the VS-300 (pictured) were

flown in prewar trials.

3. By 1936, German inventor Professor Heinrich Focke had one of the first true helicopters, the FA-61(built by the Focke-Achgelis company). It could fly at 75 mph for up 150 miles, and was flown by femaletest pilot Hanna Reitsch

4. Britain was the first nation to use helicopters during wartime, when a Sikorsky R-4 'Hoverfly' rescued apilot and three injured passengers from a plane crash in mountains of northern Burma, April 1944.

5. America began production of the Bell UH-1, "Huey" - utility helicopter (first flown in 1956) in 1959, andthis was deployed in the Vietnam War during the 1960s, as a troop transport for 'Air Cavalry' forces, andmedevac duties, then later for airborne assault to protect ground troops.

6. In 1967, the French-built Aerospatiale (Eurocopter) SA 341 Gazelle became the first helicopter tofeature a 'fenestron' tail rotor, which reduces noise levels.

7. First flown in 1975 (as YAH-64 ), the Boeing (McDonnell Douglas) AH-64 Apache attack helicopter isone of the most successful army gunships in service, with over 1,000 built in various types since 1984

8. The biggest helicopter in the world (pictured) is Russia's heavy duty Mil Mi-26 Halo, which first flew in1977. Over 200 have been built, and the mighty Halo is able to lift payloads of 20,000 kilos, in a cargo bay similar to a C-130 Hercules transport plane. Halo can cruise at 250 kph with 70 passengers or 80 troops,and has been used as an airborne hospital and a flying tanker.

9. The forward velocity of any helicopter is limited due to vibration stresses on the tips of leading rotor blades as they approach the speed of sound. On 11th August 1986, the current world speed record for ahelicopter was set by a British GKN Westland Lynx (G-LYNX, piloted by Trevor Egginton),

10. Although there were several experimental helicopters and prototypes without tail rotors, such as theHiller J-10, and McDonnell's XH-20 'Little Henry' (the world's first ram-jet helicopter, built in 1947), it wasn't until 2 July 1991 that the very first McDonnell Douglas 500 series' NOTAR (No Tail Rotor) chopper

http://www.rotaryaction.com/images/yah-64.jpghttp://www.rotaryaction.com/images/yah-64.jpg

8/3/2019 Supported in Flight by the Reactions of the Air on One or More Rotors

2/2

got airborne, later to become the world's quietest production helicopter in the 1990s.

11. The world's first hotelicopter (18 rooms with five-star facilities) - a customised and refitted Soviet- built Mil V-12 helicopter... but it's simply another hoax, unleashed on 1st April 2009.