Wing tip
Encyclopedia
A wing tip is the part of the wing that is most distant from the fuselage
Fuselage
The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...

 of a fixed-wing aircraft
Fixed-wing aircraft
A fixed-wing aircraft is an aircraft capable of flight using wings that generate lift due to the vehicle's forward airspeed. Fixed-wing aircraft are distinct from rotary-wing aircraft in which wings rotate about a fixed mast and ornithopters in which lift is generated by flapping wings.A powered...

.

Because the wing tip shape influences the size and drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...

 of the wingtip vortices
Wingtip vortices
Wingtip vortices are tubes of circulating air that are left behind a wing as it generates lift. One wingtip vortex trails from the tip of each wing. The cores of vortices spin at very high speed and are regions of very low pressure...

, tip design has produced a diversity of shapes, including:
  • Squared-off
  • Aluminium tube bow
  • Rounded
  • Hoerner style
  • Winglets
  • Drooped tips
  • Raked wingtips
  • Tip tanks
  • Sails
  • Fences
  • End plates


Winglets have become popular additions to high speed aircraft wanting to increase fuel efficiency by reducing drag from wingtip vortices. In lower speed aircraft, the effect of the wingtip shape is less apparent, with only a marginal performance difference between round, square, and Hoerner style tips. The slowest speed aircraft, STOL
STOL
STOL is an acronym for short take-off and landing, a term used to describe aircraft with very short runway requirements.-Definitions:There is no one accepted definition of STOL and many different definitions have been used by different authorities and nations at various times and for a myriad of...

 aircraft, may use wingtips to shape airflow for controlability at low airspeeds.

Wing tips are also an expression of aircraft design style, so their shape may be influenced by marketing
Marketing
Marketing is the process used to determine what products or services may be of interest to customers, and the strategy to use in sales, communications and business development. It generates the strategy that underlies sales techniques, business communication, and business developments...

 considerations as well as by aerodynamic
Aerodynamics
Aerodynamics is a branch of dynamics concerned with studying the motion of air, particularly when it interacts with a moving object. Aerodynamics is a subfield of fluid dynamics and gas dynamics, with much theory shared between them. Aerodynamics is often used synonymously with gas dynamics, with...

 requirements.

Wing tips are often used by aircraft designers to mount navigation light
Navigation light
A navigation light is a colored source of illumination on an aircraft, spacecraft, or waterborne vessel, used to signal a craft's position, heading, and status...

s, anti-collision strobe light
Strobe light
A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope...

s, landing lights
Aircraft landing lights
Landing lights are lights used on aircraft to illuminate the terrain and runway ahead during takeoff and landing.-Overview:Almost all modern aircraft are equipped with landing lights if they are intended and approved for nighttime operations...

, handholds, and identification markings.

Wing tip tanks can act as a winglet, store fuel at the center of gravity, and distribute weight more evenly across the wing spar.

On fighter aircraft
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...

, they may also be fitted with hardpoint
Hardpoint
A hardpoint, or weapon station, is any part of an airframe designed to carry an external load. This includes a point on the wing or fuselage of military aircraft where external ordnance, countermeasures, gun pods, targeting pods or drop tanks can be mounted.-Rail launchers:Large missiles and...

s, for mounting drop tank
Drop tank
In aeronautics, a drop tank is used to describe auxiliary fuel tanks externally carried by aircraft. A drop tank is expendable and often jettisonable...

s and weapons systems, such as missile
Missile
Though a missile may be any thrown or launched object, it colloquially almost always refers to a self-propelled guided weapon system.-Etymology:The word missile comes from the Latin verb mittere, meaning "to send"...

s and electronic countermeasures
Electronic countermeasures
An electronic countermeasure is an electrical or electronic device designed to trick or deceive radar, sonar or other detection systems, like infrared or lasers. It may be used both offensively and defensively to deny targeting information to an enemy...

. Wingtip mounted hose/drogue systems allow Aerial refueling
Aerial refueling
Aerial refueling, also called air refueling, in-flight refueling , air-to-air refueling or tanking, is the process of transferring fuel from one aircraft to another during flight....

 of multiple aircraft with separation.

Aerobatic
Aerobatics
Aerobatics is the practice of flying maneuvers involving aircraft attitudes that are not used in normal flight. Aerobatics are performed in airplanes and gliders for training, recreation, entertainment and sport...

 aircraft use wingtip mounted crosses for visual attitude reference. Wingtip mounted smoke systems and fireworks highlight rolling aerobatic maneuvers. Some airshow acts feature the pilot touching or dragging the wingtip along the ground.

Aircraft with a single main landing gear or very high aspect ratio wings such as gliders
Glider (sailplane)
A glider or sailplane is a type of glider aircraft used in the sport of gliding. Some gliders, known as motor gliders are used for gliding and soaring as well, but have engines which can, in some cases, be used for take-off or for extending a flight...

, may place small landing gear in the wingtips. Some uncommon designs,like the Rutan Quickie
Rutan Quickie
-See also:-External links:***...

, and Convair XFY
Convair XFY
|-See also:-References:NotesCitationsBibliography* Allen, Francis J. "Bolt Upright: Convair's and Lockheed's VTOL fighters". Air Enthusiast Volume 127, January/February 2007, pp. 13–20. ISSN 0143-5450....

 placed the main landing gear in the wingtips. Some early WWI aircraft used wooded skids on the wingtips to minimize damage on ground looping incidents.

Several amphibious aircraft such as the Consolidated PBY Catalina, use retractable wingtips as floats.

Moveable wingtips can affect the controlability of a wing. Wing warping
Wing warping
Wing warping was an early system for lateral control of a fixed-wing aircraft. The technique, used and patented by the Wright brothers, consisted of a system of pulleys and cables to twist the trailing edges of the wings in opposite directions...

 the ends of the wing, produced roll control on the earliest of aircraft such as the Wright Flyer
Wright Flyer
The Wright Flyer was the first powered aircraft, designed and built by the Wright brothers. They flew it four times on December 17, 1903 near the Kill Devil Hills, about four miles south of Kitty Hawk, North Carolina, U.S.The U.S...

. The North American XB-70 Valkyrie raised and lowered its wingtips in flight to adjust its stability in supersonic and subsonic flight.

Wingtips can also house the power plant or thrust of an aircraft. The EWR VJ 101
EWR VJ 101
-See also:-Bibliography:* Rogers, Mike. VTOL: Military Research Aircraft. New York: Orion Books, 1989. ISBN 0-517-57684-8.* Winchester, Jim. "EWR-Sud VJ 101C ". X-Planes and Prototypes. London: Amber Books Ltd., 2005. ISBN 1-904687-40-7....

 used tip mounted jets, the V-22 uses tilting wingtip mounted engines, and the Harrier uses wingtip thrust for stability while hovering.

Rotary wing aircraft wingtips may be swept or curved to reduce noise and vibration. Some rotary wing aircraft place their propulsion in wingtip tip jets.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK