Aircraft Wing

All details about aircraft wing constructional design.

1. AIRCRAFT WING PRESENTED BY: Shweta(13/618) Vishal Vyas(13/620) INTRODUCTION TO AERONAUTICS LAB

2. Topics:

3. INTRODUCTION

4. HISTORICAL BACKGROUND The Ancient Chinese : Kites with curved surfaces flew better than kites with flat surfaces . Leonardo da Vinci, 1486-1490 : The idea of strapping a pair of wings to arms fail out of favor & replaced by the concept of wing flapped up & down.

5. Lilienthal and Cayley: In the 1800s, demonstrated that a curved surface produces more lift than a flat surface Wilbur and Orville Wright: Construction of fixed wing aircraft and use of ailerons. Material used is Spurce. Discovery of wind tunnels.

6. What is Wing? “A   wing  is a type of fin with a surface  that produces   aerodynamic force  for flight or propulsion through the atmosphere, or through another gaseous  or liquid fluid. As such, wings have an airfoil shape, a streamlined  cross-sectional shape producing  lift”.

7. How Lift is Generated ? The basic principle behind an lift is described by Bernoulli's theorem. “Air that travels over the top surface of the airfoil has to travel faster and thus gains dynamic pressure. The subsequent loss of static pressure creates a pressure difference between the upper and lower surfaces that is called lift and opposes the weight of an aircraft (or thrust that opposes drag )”. As the angle of attack (the angle between the chord line and relative air flow) is increased, more lift is created. Once the critical angle of attack is reached (generally around 14 degrees) the airfoil will stall.

8. WING CONSTRUCTIONAL INTRODUCTION Wing construction is similar in most modern aircraft. In its simplest form, the wing is a framework made up of spars and ribs and covered with metal. The construction of an aircraft wing is shown in figure.

9. Internal Structure of Wing

10. Internal Structure of Wing(Contd.) Ribs:   The parts of a wing which support the covering and provide the airfoil shape . Spar:  Running  span wise  at right angles (or thereabouts depending on  wing sweep ) to the  fuselage . Stringers:   A strip of wood or metal to which the skin of an aircraft is fastened

11. Internal Structure of Wing(Contd .) Skin: The outer surface of the wing. Originally made of fabric, modern aircraft use aluminum or composite materials due to their lightweight and rust-resistant properties. Fuel Tank: Commonly located in the wing, fuel can either be housed in its own tank or allowed to fill the cavities between the ribs . Flaps : Are a “high lift / high drag” device. Not only do they improve the lifting ability of the wing at slower speeds by changing the camber, or curvature of the wing, they also create more drag, meaning an aircraft can descend, or lose altitude faster, without gaining airspeed in the process.

12. Internal Structure of Wing(Contd .) Root: The wing root is the portion of the wing that attaches to the fuselage, or body of the aircraft. Wing Tip: The wing tip is furthest from the fuselage and is typically where the navigation lights are mounted (a red light on the left, a green light on the right). Slats: Another “high lift” device typically found on swept or delta wing aircraft. Slats are similar to the flaps except they are mounted on the leading edge of the wing. They also assist in changing the camber to improve lifting ability at slower speeds.

13. Aspect Ratio: The ratio of the wing’s length to its chord line. Camber : The name given to the curvature of the upper or lower surfaces of the wing. Chord Line: The theoretical line running from the leading edge of the wing to the trailing edge. Leading Edge: The front edge of an aircraft’s wing. Trailing Edge: The rear edge of an aircraft’s wing. Wing Construction & Mathematics

14. Types of Wings? On the Basis of:

15. Based on Position

16. Based on Structure

17. Aileron: Ailerons increase or decrease lift asymmetrically, in order to change roll and, thus, move the aircraft left or right while flying. Ailerons are hinged sections fitted at the rear of each wing Stability Devices on Wings

18. Stability Devices on Wings(Contd.) Flaps: Flaps  are devices used to alter the lift characteristics of a wing and are mounted on the trailing edges of the  wings  of a fixed-wing aircraft to reduce the speed at which the aircraft can be safely flown and to increase the angle of descent for landing. They shorten take off and landing distances. Flaps do this by lowering the stall speed and increasing the drag.

19. Airfoil Leading Edge  = Forward edge of the aerofoil Trailing Edge  = Aft edge of the aerofoil Chord  = Line connecting the leading and trailing edge. Denotes the length of the aerofoil Mean Camber Line  = Line drawn half way between the upper and lower surface of the aerofoil. Denotes the amount of curvature of the wing Point of Maximum Thickness   = Thickest part of the wing expressed as a percentage of the chord Airfoil: It is the shape of a  wing  or blade ( of a  propeller ,  rotor, or turbine ) or   sail  as seen in  cross-section .

20. Development of wings from 1900-2015

21. SOME UNCONVENTI0NAL DESIGNS Drawbacks of Conventional Wings: Higher control power required. Incurring extra drag and fuel consumption increases. At high angles of attack stall problems occurred. Flap deployment causes nose down pitching moments which must be overcome by elevator and/or horizontal tail deflection causing the overall maximum lift to go down.

22. Features of some unconventional designs The canard (forward lifting surface) is lifting. Weight savings since the horizontal tail is eliminated . Savings in drag which will result in better speed and range characteristics (lower fuel consumption).

23. Thank You