POF 02

1. The angle shaded in blue in this diagram is the: [Abbildung erforderlich: siehe Original-PDF, Seite 1. Grafik nicht in dieser CSV enthalten.] A) Angle of incidence. B) Angle of attack.

2. The outline shape of the wings when seen from above is called the wing __________. A) planform B) camber C) aspect ratio

3. Aspect ratio is the ratio of wingspan to average wing __________. A) chord B) length C) thickness

4. Aspect ratio is the ratio of __________ to average wing chord. A) wing span B) wing area

5. The chord of an imaginary rectangular wing which has similar longitudinal stability properties to the actual wing is called the __________ __________ __________. A) mean aerodynamic chord B) mean camber line C) mean aspect ratio

6. The angle of incidence __________. The angle of attack __________. A) is fixed; changes. B) changes; changes. C) changes; is fixed. D) is fixed; is fixed.

7. The ratio of the wing tip chord to root chord is the __________ ratio. A) taper. B) aspect. C) angle. D) planform.

8. Tip vortices are caused by the flow of air from __________ the wing around the wing tip towards the other surface of the wing. A) under B) over

9. Tip vortices rotate __________ the aircraft. A) towards. B) away from.

10. Tip vortices __________the downwash behind the wing. This is why, with 3D flow, we must use the __________ airflow rather than the relative airflow and measure the __________. A) increase; effective; induced angle of attack B) increase; effective; induced incidence angle C) increase; real; induced incidence angle D) increase; real; induced angle of attack E) decrease; real; induced incidence angle F) decrease; real; induced angle of attack G) decrease; effective; induced angle of attack H) decrease; effective; induced incidence angle

11. Span wise flow is caused by: A) The pressure gradient along the wing. B) An area of relatively low pressure under the wing. C) An area of relatively low pressure at each wing root. D) The downwash behind the wing.

12. Wake turbulence is caused by tip vortices. The vortices migrate __________ and eventually stabilise at a vertical distance of about __________ ft from the aircraft. A) downwards; 900. B) upwards; 900. C) downwards; 250. D) downwards; 2000.

13. Wake turbulence can be hazardous for __________ behind a large, heavy aircraft. A) several miles B) several hundred metres

14. Tip vortices are strongest when the aircraft is __________ and __________. A) slow; heavy. B) fast; heavy C) slow; light. D) fast; light.

15. Tip vortices __________ with an increase in alpha. A) increase. B) decrease. C) do not change.

16. Which of the following statements about induced drag is most correct. A) Induced drag is the result of the lift vector being tipped backwards owing to the change in the angle of the free stream air flow. B) Induced drag is the result of the lift vector being tipped backwards because the effective angle of attack is greater than the angle of attack. C) Induced drag reduces with an increase in aircraft mass. D) Induced drag increases with air speed. E) Induced drag is the result of the lift vector being tipped backwards because of the change in the angle of incidence.

17. In these plots of spanwise lift distribution. Mark 2 correct answers. A) The red curve shows the lift distribution of a swept, tapered wing. B) The green curve shows an elliptical lift distribution. C) The red curve shows the lift distribution of a rectangular wing D) The green curve shows the lift distribution of a tapered rectangular, tapered wing.

18. The ideal pattern for the span wise distribution of lift is one where the majority of the lift is produced inboard. This can be produced by __________ wing planform. A) an elliptical B) rectangular

19. High aspect ratio wings produce __________ tip trailing vortices and are therefore inherently __________ efficient than low aspect ratio wings. A) weaker; more. B) weaker; less. C) stronger; more. D) stronger; less.

20. The weight per unit of wing area (kg/m²) gives the value for the __________ __________. A) wing loading B) wing aspect ratio C) coefficient of lift

21. A higher aspect ratio wing produces a __________ CL alpha curve and a __________ critical angle. A) steeper; smaller. B) steeper; larger. C) shallower; larger. D) shallower; smaller.

22. Which of the following wing planforms produces an increase in downwash towards the wingtip? A) rectangular. B) sweepback. C) elliptical. D) taped.

23. Wing loading' is the __________ per unit of __________ __________. A) weight; wing area B) g force; wing area C) weight; wing span D) g force; wing span

24. Which of the following statements is most accurate. A) Biasing the spanwise lift distribution to maximise lift inboard reduces drag. B) An elliptical lift distribution minimises tip vortices and thus minimises parasite drag. C) Tip vortices increase downwash but have little effect on drag. D) Tip vortices are stronger with lower wing loading.

25. A swept wing __________ downwash at the wing tips. A) increases. B) decreases. C) has no effect on.

26. Parasite drag comprises:Mark 3 correct answers. A) Interference drag. B) Skin friction drag. C) Form drag. D) Induced drag. E) Wave drag.

27. The main factors affecting form drag are: A) Airspeed, frontal area, shape and streamlining, surface roughness. B) Frontal area, wing planform shape, surface roughness. C) Angle of attack, frontal area, shape and streamlining, surface roughness. D) Airspeed, angle of attack, surface area, streamlining, frontal area.

28. __________ forces in the boundary layer are the primary cause of skin friction drag. A) Shear B) Momentum

29. The main factors affecting skin friction drag are: A) Airspeed, surface area and boundary layer conditions. B) Airspeed, frontal area and boundary layer conditions. C) Surface area, boundary layer conditions and tip vortices. D) Alpha, surface area and boundary layer conditions.

30. __________ drag is the drag resulting from the mixing of airflows over surfaces of different orientations. A) Interference B) Induced

31. Parasite drag increases with __________. A) V² B) V C) alpha

32. Which of the following statements is/are correct? A) Induced drag increases when the aircraft is manoeuvred at positive g. B) Induced drag increases with aircraft mass. C) Induced drag is caused by vortices with occur only when lift is being created. D) Induced drag is caused by tip vortices which occur at any positive forward speed. E) Induced drag increases with speed in level flight.

33. Which of the following are valid measures to reduce induced drag:Mark 3 correct answers. A) Wing twist B) High aspect ratio C) Winglets D) Low aspect ratio E) Increasing camber towards the wing tips

34. Induced drag is inversely proportional to __________. A) V² B) V C) alpha

35. CDI is __________ proportional to aspect ratio and __________ proportional to the CL². A) inversely; directly. B) inversely; inversely. C) directly; directly. D) directly; inversely.

36. In banked, level flight an aircraft produces __________ drag than the same aircraft flying wings level. A) more B) less C) the same amount of

37. On take-off, tip vortices start to be produced __________. A) when the aircraft rotates B) when the aircraft begins its take-off roll

38. Lowering the landing gear increases __________ . A) form drag B) induced drag

39. A turbulent boundary layer is __________ draggy than a laminar boundary layer. A) more B) less C) equally

40. An increase in mass causes the drag curve to move __________ and ________. A) up; right. B) down; right. C) up; left. D) down; left.

41. On a Drag-__________ plot, altitude has no effect on the position of the Total Drag curve. A) IAS B) TAS C) CLMAX

42. On a Drag/TAS plot, the bottom of the total drag curve indicates __________. On a Drag/IAS plot the bottom of the total drag curve indicates __________. A) VMD; VIMD B) VMD; VMD C) VIMD; VMD D) VIMD; VIMD

43. Because drag is related to __________ __________ altitude has no effect on the position of the total drag curve. A) Dynamic pressure. B) Static pressure C) Total pressure. D) Induced pressure.

44. A general purpose aerofoil is most efficient (best L/D ratio) at about __________ alpha. A) 4° B) 2° C) 16° D) 6°

45. Study the image carefully then identify which of the following statements is correct. A) D is the most efficient wing because it has the best L/D ratio. B) C is the most efficient wing because the amount of lift and drag are in perfect balance. C) B is the most efficient wing because it is producing the least amount of drag at 4° alpha. D) A is the most efficient wing because it is producing the most lift at 4° alpha. E) A is the most efficient wing because it has the best L/D ratio.

46. The value of the induced drag of an aeroplane in straight and level flight at constant mass varies linearly with:

47. Increasing dynamic pressure will have the following effect on the total drag of an aeroplane:

48. Comparing the lift coefficient and drag coefficient for conventional aeroplanes:

49. Winglets:

50. Decreasing the aspect ratio of a wing:

51. An aeroplane on final approach is flying at a CAS lower than VMD, which means it is speed unstable. If the speed suddenly decreases, what effect do parasite and induced drag have on total drag?

52. From a polar curve of the entire aeroplane one can read:

53. An aircraft wing has a CL of 0.38. The pilot deploys a stage of flaps, then decreases speed to maintain the same altitude. Which of the following is correct?

54. An aeroplane maintains straight and level flight while the IAS is doubled. The change in lift coefficient will be:

55. If you are flying at 1.4 VS and accelerate to 2.4 VS, by how much will the coefficient of lift decrease by?