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2013-11-18 20:55:14

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  1. An ______ in velocity or density will produce more lift.
  2. An _____ in wing surface area produces greater lift.
  3. Within the lift equation, pilots have no control over the CL factors of ____, ____, or _____.
    viscosity; compressibility; aspect ratio
  4. Three lift equation factors a pilot can control are ____, ____, and ______.
    velocity; angle of attack; shape of the airfoil or camber
  5. What is the critical angle of attack?
    • The AOA that corresponds to the max coefficient of lift
    • Increasing the AOA beyond the critical angle of attack causes a decrease in lift due to boundary layer separation
    • Stall
  6. As the AOA is increased, the pilot will have to ____ velocity to maintain level flight
  7. If AOA is _____ then velocity must increase
  8. What is aerodynamic twist?
    • decrease in camber from the wing root to the wing tip
    • Positive camber at wing root, symmetric shape at wing tip
  9. What does an aerodynamic twist do to stall characteristics?
    • The wing root will stall before the wing tip
    • Positively cambered airfoil stalls at a lower AOA than a symmetric airfoil
  10. What is a geometric twist?
    • Decrease of angle of incidence from wing root to wing tip
    • Wing root is always at a greater AOA than the wing tip
  11. What does a geometric twist do to stall characteristics?
    Wing root will always stall first, providing a stall indication before the ailerons become ineffective
  12. What is parasite drag?
    • drag that is not associated with the production of lift
    • Increases as velocity increases
    • Form drag
    • Friction drag
    • Interference drag
  13. Parasite drag
    What is form drag?
    • The result of separation of airflow from a surface and the wake that is created by that separation
    • Occurs as object moves through a fluid
    • Difference between leading edge static pressure and trailing edge static pressure
  14. Parasite drag
    What is friction drag?
    • turbulent airflow in the boundary layer
    • Reduced by smoothing the exposed surface
  15. Parasite drag
    What is interference drag?
    generated by mixing airstreams between aircraft components
  16. What is induced drag?
    • drag that is associated with production of lift
    • Weight and AOA are directly related to induced drag
    • Wingtip vortices
  17. In level flight where lift is constant, induced drag varies _____ with velocity and directly with AOA.
  18. What is significant about L/DMAX?
    • Minimum total drag
    • Parasite drag = induced drag
    • Greatest ratio of lift to drag (not max lift)
    • Most efficient AOA for the wing
  19. What is ground effect?
    Within one wingspan of the ground, induced drag is significantly reduced because the ground blocks the downwash from the wing
  20. Define thrust available
    The amount of thrust that is produced by an engine at a give PCL setting, velocity and density
  21. What is maximum velocity?
    • At max power, equilibrium flight will be maintained when thrust available equals thrust required.
    • 255 KIAS
  22. What is thrust excess?
    • Occurs if thrust available is greater than thrust required at a particular velocity
    • Positive thrust excess will cause a climb, acceleration or both depending on AOA
    • Lack of excess thrust causes a descent, deceleration or both depending on AOA
    • Max excess thrust occurs at a velocity less than L/DMAX
  23. Define power available
    The amount of power that an engine is producing at a given PCL setting, velocity, and density
  24. What is power required?
    Is the amount of power required to produce thrust required
  25. What is power excess?
    • Positive power excess results in a climb, acceleration or both
    • Lack of excess power causes a descent, deceleration, or both
    • Maximum excess power occurs at L/DMAX
  26. What happens to the thrust and power required curves as weight is added?
    The net result is that increased weight shifts the power and thrust curves up and right
  27. What happens to the thrust required factor as altitude is increased, assuming weight is constant?
    • Velocity must increase due to the decrease in air density.
    • The curve must shift to the right as altitude increases.
  28. What happens to the power required curve as altitude increases?
    Curve shifts to the right and up due to the increase in velocity, because power is a constant function of thrust required and velocity
  29. What happens to thrust available and power available at altitude increases?
    • Max engine output decreases with decreased air density
    • Both will decrease
  30. Plain flap
    Simple hinged portion of trailing edge of the wing that is forced down into the airstream
  31. Split flap
    • Plate deflected from the lower surface of the wing.
    • Creates more drag
    • T6 has split flap
  32. Slotted flap
    Similar to plain flap, but moves away from the wing to open a narrow slot between the flap and wing for boundary layer control
  33. Fowler flap
    • Used on large aircraft
    • Moves down to increase camber and aft to increase wing surface area, increasing lift
  34. What flap setting gains more lift than increased drag?
    50% of flap setting

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