1. Uncontrolled copy not subject to amendment Principles of Flight

2. Learning Outcome 2: Understand how the stability of an aeroplane is maintained in flight and how manoeuvrability is controlled Part 3

3. Principles of Flight Revision

4. Questions What happens to Lift when a Wing is Stalled? a.Lift Increases as Angle of Attack Decreases. b.Lift Decreases as Angle of Attack Increases. c.Lift is Greatly Reduced. d.Lift Remains unchanged.

5. Questions The Critical Angle of Attack is Generally about? a. 5 o. b.15 o. c.25 o. d.35 o.

6. Questions Which of the following will NOT REDUCE the Stalling Speed? a.Extra Weight. b.Larger Wing Area. c.Flaps Lowered. d.Flaps Raised.

7. Questions Where would you find the information regarding the Aircraft’s various Stalling Speeds? a.Pilot’s Notes. b.Air Traffic Control. c.Ground Crew. d.McDonald’s.

8. High Lift Devices (Flaps) or Lift Augmentation

9. High Lift Devices Objectives: 1.Describe the principle operation of Trailing Edge Flaps. 2.State the following for Trailing Edge Flaps: Location, Effects on Lift, Effects on Drag, Types, Advantages, and uses. 3. Describe the principle operation of Leading Edge Slats. 4.State the Advantages of Slats with reference to: Stalling Speed, Stalling Angle, and Drag.

10. High Lift Devices Why do we need High Lift Devices? High Lift Devices come in many shapes and forms. They are mounted on the Leading and Trailing edges of wings. They create more Lift at lower speeds to allow lower take-off and landing speeds. The Aircraft nose will be lower, allowing a better view for the Pilot. But how do they work?

11. LIFT AUGMENTATION Weight (Constant) = Lift (Constant) = C L ½ρV 2 S At Minimum Speed = C LMAX ½ρV 2 MIN S To further reduce the Minimum Speed? Raise the Value of C LMAX THIS IS THE PURPOSE OF LIFT AUGMENTATION

12. METHODS OF LIFT AUGMENTATION FLAPS (Trailing Edge & Leading Edge) SLATS & SLOTS

13. LIFT AUGMENTATION DEVICES PLAIN FLAP 50% Increase C LMAX Critical Angle 12 o

16. LIFT AUGMENTATION DEVICES 60% Increase C LMAX Critical Angle 14 o SPLIT FLAP

17. NIMROD Split Flap

18. LIFT AUGMENTATION DEVICES 65% Increase C LMAX Critical Angle 16 o SLOTTED FLAP

22. LIFT AUGMENTATION DEVICES THE BLOWN FLAP 80% Increase C LMAX Critical Angle 16 o

23. LIFT AUGMENTATION DEVICES FOWLER FLAP 90% Increase C LMAX Critical Angle 15 o

25. LIFT AUGMENTATION DEVICES AUTOMATIC SLAT 70% Increase C LMAX Critical Angle 25 o

26. LIFT AUGMENTATION DEVICES FIXED SLAT 50% Increase C LMAX Critical Angle 20 o

27. LIFT AUGMENTATION DEVICES 40% Increase C LMAX Critical Angle 20 o SLOT

28. LIFT AUGMENTATION DEVICES KRUGER FLAP 50% ? Increase C LMAX Critical Angle 25 o

30. LIFT AUGMENTATION DEVICES “DROOP SNOOT” FLAP 50% ? Increase C LMAX Critical Angle 20 o

31. LIFT AUGMENTATION - EFFECTS ON C L

32. α CLCL BASIC AEROFOIL SECTION

33. LIFT AUGMENTATION - EFFECTS ON C L α CLCL BASIC AEROFOIL SECTION TRAILING EDGE FLAP

34. LIFT AUGMENTATION - EFFECTS ON C L α CLCL BASIC AEROFOIL SECTION LEADING EDGE FLAP

35. LIFT AUGMENTATION - EFFECTS ON C L α CLCL BASIC AEROFOIL SECTION SLAT OR SLOT

36. LIFT AUGMENTATION - EFFECTS ON C L α CLCL BASIC AEROFOIL SECTION TRAILING EDGE FLAP LEADING EDGE FLAP SLAT OR SLOT

37. Flaps But, what about Drag? Flaps 30 o Flaps 90 o Flaps 60 o Flap 30 o 60 o 90 o Drag Small Inc Large Inc V Large Inc Lift Large Inc Small Inc No Sig Inc

39. Any Questions?

40. High Lift Devices Objectives: 1.Describe the principle operation of Trailing Edge Flaps. 2.State the following for Trailing Edge Flaps: Location, Effects on Lift, Effects on Drag, Types, Advantages, and uses. 3. Describe the principle operation of Leading Edge Slats. 4.State the Advantages of Slats with reference to: Stalling Speed, Stalling Angle, and Drag.

41. Questions What effect does a Trailing Edge Flap have on the Stalling Speed? a.Higher. b.Lower. c. The same. d. No difference.

42. Questions One type of Leading Edge Flap is: a.Plain. b.Slot. c. Split. d. Kruger.

43. Questions What are some of the High Lift Devices on the Leading Edge called? a. Plain Flaps. b. Ailerons. c. Slats. d. Split Flaps.