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[[Image:ADV0300.jpg|right]]

A '''helicopter''' is a rotary wing [[aircraft]]. It is lifted by an horizontal rotor. The adventages of the helicopter is due to the ability to lift upward. The limitation of the helicopter is its relativity slow speed. The first practical helicopter was developed in 1939 by [[Russian]]-born [[Igor Sikorsky]] (1889–1972).  

A '''helicopter''' is a rotary wing [[aircraft]].   The first practical helicopter was developed in 1939 by [[Russian]]-born [[Igor Sikorsky]] (1889–1972).  

''Helicopter flight was the first flight envisioned by man. In fact, the ancient [[Chinese]] were playing with a hand-spun toy that rose upward when revolved rapidly and as early as the mid 1500's, the great [[Italian]] inventor [[Leonardo da Vinci]] had used his fertile mind to make drawings of a machine that we now know as the helicopter.''<ref> [http://www.helis.com/ Helicopter History Site]

''Helicopter flight was the first flight envisioned by man. In fact, the ancient [[Chinese]] were playing with a hand-spun toy that rose upward when revolved rapidly and as early as the mid 1500's, the great [[Italian]] inventor [[Leonardo da Vinci]] had used his fertile mind to make drawings of a machine that we now know as the helicopter.''<ref> [http://www.helis.com/ Helicopter History Site]

Bell Helicopter Textron, is a producer of commercial and military helicopters, and the pioneer of the revolutionary tiltrotor aircraft.  

Bell Helicopter Textron, is a producer of commercial and military helicopters, and the pioneer of the revolutionary tiltrotor aircraft.  

== See also ==

== See also ==