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Vertical Takeoff and Landing Aircraft
Vertical Takeoff and Landing Aircraft (known as VTOL aircraft) debuted in the Korean War primarily in the medevac role. The venerable piston‐powered Bell 47 (H‐13) helicopter provided the U.S. Army with an unprecedented ability to rapidly evacuate wounded personnel for lifesaving treatment. VTOL technology was first used in a significant combat role by U.S. forces during the Vietnam War. This was made possible by the advent of a practical turbine engine, providing excellent horsepower‐to‐weight ratios, coupled with advances in lightweight aluminum honeycomb construction techniques and epoxies that made strong, lightweight airframes possible, and rotor systems vastly improved over the older wooden blades. These technologies culminated in the Bell UH‐1 (Huey), OH‐58 (Kiowa), and AH‐1 (Cobra), the Boeing Vertol CH‐47 (Chinook), the Sikorsky CH‐54 (SkyCrane), and the Hughes OH‐6 (Cayuse). The civilian helicopter fleet during and after the Vietnam War was an outgrowth of the technology pioneered by the military, in which many aircraft were nearly indistinguishable from their military cousins.
One unique VTOL aircraft is the USMC single‐pilot Harrier ground attack/fighter aircraft. Developed by British Aerospace in the 1960s, the Harrier flies in the vertical flight mode solely by vectored thrust from a single engine, allowing overflight with transition to forward jet flight at the flick of a wrist. While rather fuel‐inefficient and very noisy, the Harrier stands alone as the only operational VTOL jet worldwide. VTOL aircraft have revolutionized combat for the ground forces over the last fifty years, and the technology developed has found numerous uses in the civilian world. Improvements in VTOL technology, such as the U.S. Navy/Marine V‐22 “Osprey” tilt‐rotor aircraft, may someday make VTOL aircraft the rule and eliminate the need for runways in either military or civilian aviation. [See also Helicopters.] Mark Cannon |
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Cite this article
John Whiteclay Chambers II. "Vertical Takeoff and Landing Aircraft." The Oxford Companion to American Military History. 2000. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. John Whiteclay Chambers II. "Vertical Takeoff and Landing Aircraft." The Oxford Companion to American Military History. 2000. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O126-VerticalTakffndLndngrcrft.html John Whiteclay Chambers II. "Vertical Takeoff and Landing Aircraft." The Oxford Companion to American Military History. 2000. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O126-VerticalTakffndLndngrcrft.html |
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vertical takeoff and landing aircraft
vertical takeoff and landing aircraft (VTOL), craft capable of rising and descending vertically from and to the ground, thus requiring no runway. While a balloon or an airship has obvious VTOL capability, both are very inefficient at moving parallel to the earth's surface. The autogiro and the helicopter offer some improvement in this respect, but still have very limited performance. A large number of VTOL designs have been produced and tried. The pogo-stick, or tail-sitting, type was similar in appearance to a conventional airplane except for a special tail on which it took off and landed. This type was abandoned, partly because of the difficulty in maintaining fine control when its fuselage was positioned vertically, e.g., during a landing. Convertiplanes are VTOL craft that can fly horizontally with the same effectiveness as a conventional airplane. Some convertiplanes are conventional-looking aircraft that can tilt their rotors, or oversize propellors, so that the rotors' axes are vertical during takeoff and landing and are horizontal during forward flight. The best-known such tilt-rotor aircraft is the V-22 Osprey, which first flew in 1989. The Harrier is a jet fighter convertiplane that uses vanes to direct the thrust of its engine upward or forward and is capable of flight at approximately the speed of sound; it proved its ability to control a battlefield despite the absence of airports and runways during the 1982 Falklands conflict. |
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Cite this article
"vertical takeoff and landing aircraft." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "vertical takeoff and landing aircraft." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-verttak.html "vertical takeoff and landing aircraft." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-verttak.html |
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vertical/short takeoff and landing aircraft
vertical/short takeoff and landing aircraft V/STOL an aircraft capable of executing a vertical takeoff and landing, a short takeoff and landing, or any combination of these modes of operation.
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Cite this article
"vertical/short takeoff and landing aircraft." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "vertical/short takeoff and landing aircraft." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O63-vrtclshrttkffndlndngrcrf1.html "vertical/short takeoff and landing aircraft." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-vrtclshrttkffndlndngrcrf1.html |
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vertical takeoff and landing
vertical takeoff and landing the capability of an aircraft to take off and land vertically and to transfer to or from forward motion at heights required to clear surrounding obstacles.
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Cite this article
"vertical takeoff and landing." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "vertical takeoff and landing." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O63-verticaltakeoffandlanding.html "vertical takeoff and landing." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-verticaltakeoffandlanding.html |
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vertical/short takeoff and landing aircraft
vertical/short takeoff and landing aircraft VTOL any aircraft capable of taking off and landing either horizontally, using a short runway, or vertically.
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Cite this article
"vertical/short takeoff and landing aircraft." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "vertical/short takeoff and landing aircraft." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O63-vrtclshrttkffndlndngrcrft.html "vertical/short takeoff and landing aircraft." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-vrtclshrttkffndlndngrcrft.html |
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