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(a helicopter is a type of ‘rotorcraft’ in which ‘lift’ + ‘thrust’ are supplied by ‘rotors’)
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(this allows the helicopter to take off and land vertically, to ‘hover’, and to fly forward, backward, and laterally)
(these attributes allow ‘helicopters’ to be used in congested or isolated areas where ‘fixed-wing aircraft’ and many forms of ‘VTOL’ (‘vertical takeoff and landing’) aircraft cannot perform)
(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”)
(English language nicknames for helicopter include “chopper”, “copter”, “helo”, “heli”, and “whirlybird”)
(‘Helicopters’ were developed and built during the first half-century of ‘flight’, with the ‘Focke-Wulf Fw 61’ being the first operational helicopter in 1936)
(some helicopters reached limited production, but it was not until 1942 that a helicopter designed by ‘Igor Sikorsky’ reached full-scale production, with 131 aircraft built)
(though most earlier designs used more than one main ‘rotor’, it is the ‘single main rotor’ with anti-torque ‘tail rotor’ configuration that has become the most common helicopter configuration)
(‘tandem rotor helicopters’ are also in widespread use due to their greater payload capacity)
(‘co-axial helicopters’, ’tiltrotor aircraft’, and ‘compound helicopters’ are all flying today)
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(‘quad-copter helicopters’ pioneered as early as 1907 in ‘france’, and other types of ‘multi-copter’ have been developed for ‘specialized applications’ such as ‘unmanned drones’)
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💕💝💖💓🖤💙🖤💙🖤💙🖤❤️💚💛🧡❣️💞💔💘❣️🧡💛💚❤️🖤💜🖤💙🖤💙🖤💗💖💝💘
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*🌈✨ *TABLE OF CONTENTS* ✨🌷*
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🔥🔥🔥🔥🔥🔥*we won the war* 🔥🔥🔥🔥🔥🔥