AE103

Card Set Information

Author:
strent61
ID:
247936
Filename:
AE103
Updated:
2013-11-21 23:28:16
Tags:
Aerodynamics
Folders:

Description:
15-02
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user strent61 on FreezingBlue Flashcards. What would you like to do?


  1. Define Vector
    Quantity of magnitude and direction
  2. Define Force
    Push or pull exerted on a body
  3. Define Mass
    Quantity of molecular material
  4. Define Volume
    Amount of space occupied
  5. Define Density
    Mass/Volume (Mass per unit volume)
  6. Define Weight
    Force toward the Earth on mass (gravity)
  7. Define Moment
    Force applied a distance from a fulcrum
  8. Define Work
    Done when a force moves a body

    Force x distance
  9. Define Power
    Work per unit time - Work/Time
  10. Define Energy
    Capacity to do work
  11. Define Potential Energy
    Energy of position or state
  12. Define Kinetic Energy
    Energy of motion
  13. What happens to air density and temperature as altitude increases?
    Both decrease
  14. What atmospheric properties affect pressure?
    Density - p

    Temperature - T

    P = pRT (R= gas constant)
  15. What is static pressure?
    Force that molecules of air exert on each other by their random movement
  16. What is dynamic pressure?
    Measurement of impact pressure of a large group of air molecules moving together
  17. What is total pressure?
    Dynamic + static
  18. Define True altitude
    Actual height above MSL
  19. Define Pressure altitude
    Height above standard datum plane (29.92)
  20. Define Density altitude
    Pressure altitude corrected for temperature
  21. Define Indicated airspeed
    Airspeed from ASI
  22. Define Calibrated airspeed
    IAS corrected for instrument error
  23. Define Equivalent airspeed
    CAS corrected for compressibility 

    significant approached speed of sound
  24. Define True airspeed
    Speed through an air mass
  25. What is groundspeed?
    TAS corrected for winds
  26. What happens to TAS in a constant IAS climb?
    Increases
  27. Define Wingspan
    Length, wingtip to wingtip
  28. Define Chordline
    Infinitely long line through leading & trailing edge of airfoil
  29. Define Chord
    Width of wing

    Measure of the wing along the chordline, from leading edge to trailing edge
  30. Define Tip chord
    Width of wing at tip
  31. Define Root chord
    Width of wing at root
  32. Define Average chord
    Average of all chords
  33. Define Wing area
    Wingspan times average chord
  34. Define Taper
    Reduction in chord from root to tip
  35. Define Sweep angle
    Angle between 1/4 chord line and line parallel to the lateral axis
  36. Define Aspect ratio
    Wingspan/average chord
  37. Define Wing loading
    Weight/wing area
  38. Define Angle of incidence
    Angle between chordline and longitudinal axis
  39. Define Dihedral angle
    Upwards slope of wing viewed from head-on
  40. Define Pitch attitude
    Angle between longitudinal axis and horizon
  41. Define Flight path
    Aircraft path through air
  42. Define Relative wind
    Airflow experienced by aircraft/airflow
  43. Define Angle of attack
    Angle between relative wind and chordline
  44. Define Mean camber line
    Line halfway between upper and lower surface of airfoil
  45. Define Symmetric airfoil
    Mean camber and chordline are equal
  46. Define Aerodynamic center
    Point on chordline where changes in aerodynamic forces take place
  47. Define Spanwise/chordwise flow
    Spanwise- parallel to leading edge

    Chordwise- perpendicular to leading edge (produces lift)
  48. What is the relationship of thrust and drag, lift and weight, in level, unaccelerated flight?
    Thrust = drag; Lift = weight
  49. What is the relationship between lift and weight, thrust and drag, during takeoff ground roll?
    Weight > lift; Thrust > drag
  50. What is equal, but opposite relative wind?
    Flight path
  51. What are the three airplane axis?
    Longitudinal, vertical, lateral
  52. What are the motions about the axis?
    • Roll - Longitudinal
    • Yaw - Vertical
    • Pitch - Lateral
  53. Aileron axis?
    Roll
  54. Elevator axis?
    Pitch
  55. Rudder axis?
    Yaw
  56. What is the center of gravity?
    Point where weight is concentrated
  57. What is the normal relationship between the aerodynamic center and the center of gravity?
    CG is forward of aerodynamic center
  58. What are the results of the CG being too far aft or too far forward?
    • Too far aft - tail heavy
    • Too far forward - nose heavy
  59. What are the components of aerodynamic force?
    Lift and drag
  60. What is the relationship of lift and drag to the relative wind?
    • Drag is parallel
    • Lift is perpendicular
  61. Changing which factor in the lift equation will affect lift the most?
    V (velocity)

    L = 1/2pV2CLS
  62. How can the pilot change lift?
    Primarily with AOA and velocity

    Also by changing camber with flaps
  63. What is the relationship between velocity and angle of attack in level flight?
    Inverse relationship; AOA increases as velocity decreases
  64. What factor changes in maintaining level flight at 1000 ft versus 18000 ft?
    TAS increases (decreased density requires increased velocity)
  65. What is total drag?
    Parasite + induced
  66. What are the 3 types of parasite drag?
    Form, Friction, Interference
  67. Define Form drag
    The difference between static pressure of the leading and trailing edges
  68. Define Friction drag
    Turbulent airflow in the boundary layer
  69. Define Interference drag
    Mixing airflows between aircraft components
  70. What effect does lowering the gear have on drag?
    Parasite drag increases
  71. What happens to pitch as the gear is lowered?
    Nose pitches down
  72. Describe the effects on lift and drag causes by raising or lowering flaps
    Lowering T/O flaps - more lift/little more drag

    Lowering flaps from T/O to LDG - little more lift/ lot more drag

    Raising from LDG to T/O - Lot less lift/ little less drag
  73. What is induced drag?
    Drag from lift
  74. How does increased weight change induced drag?
    Increases induced drag (airspeed constant)
  75. At what velocities is induced drag greatest?
    • Greatest - slower
    • Least - faster
  76. In level unaccelerated flight, what is the relationship between total drag and total thrust?
    Equal
  77. What is the relationship between total drag and velocity?
    Drag decreases to a point, then increases
  78. What is L/DMAX
    Lowest point on the total drag curve

    the ratio of lift to drag is greatest
  79. Contrast thrust and shaft horsepower
    • Shaft - engine output
    • Thrust - propeller output
  80. What is propeller efficiency?
    Ability to convert shaft HP to thrust HP
  81. Is 100% propeller efficiency possible?
    No, gearbox friction and propeller drag
  82. What determines power available?
    Power produced at a given PCL setting, velocity and density
  83. Define Thrust required
    Thrust needed to overcome drag (TR = DT)

    Thrust required = Total drag
  84. Define Power required
    Power needed to produce TR (thrust required)
  85. Define Excess thrust
    TA > TR ; climb or accelerate

    Thrust available > Thrust required
  86. Define Excess power
    PA > PR ; climb or accelerate

    Power available > Power required
  87. What is the relationship between velocity and, TR and PR?
    TR decreases to L/DMAX then increases

    • PR decreases to airspeed below L/DMAX then increases
  88. What is the result of PA being greater than PR?
    Acceleration or climb
  89. What happens to power required as altitude increases?
    Increases
  90. What effect does a change in configuration have on TA and TR?
    No effect on TA

    Gear and/or flaps down requires increased TR
  91. What effect does a change in configuration have on PA and PR?
    No effect change on PA

    Gear and/or flaps down requires increased PR
  92. What factors increase takeoff or landing roll?
    More weight; Higher alt; Warm temp; Higher humidity; Less headwind; More tailwind
  93. Changing which factor has the greatest effect on performance?
    Weight
  94. Define Max rate of climb
    Most alt in least time
  95. Define Max angle of climb
    Most alt in least distance
  96. Define Best glide speed
    Airspeed that gives max power-off range
  97. Define Max range
    Max distance for set amount of fuel
  98. Define Max endurance
    Max time airborne for set amount of fuel
  99. What factors decrease glide range?
    Dirty configuration; Unfeathered prop; Lower alt; More headwind; Less tailwind
  100. What factor changes groundspeed, but has no effect on TAS?
    Headwind or Tailwind
  101. Where does max range for a propeller aircraft occur?
    L/DMAX
  102. Where does max endurance occur?
    Some airspeed less than L/DMAX
  103. What factors increase both max range and max endurance?
    Less weight; Clean config; Higher alt; Colder temp
  104. Where is the region of reverse command?
    Left of max endurance on PR chart
  105. What is the region of reverse command?
    The part of the PR curve where a decrease in airspeed requires an increase in power
  106. What is critical Mach?
    Airspeed where first evidence of local supersonic flow occurs
  107. Yaw resulting from propeller airflow past rudder
    Slipstream swirl
  108. Roll opposite propeller rotation
    Propeller torque
  109. Yaw resulting from asymmetric propeller thrust
    P-factor
  110. Action to correct slipstream swirl
    Right rudder
  111. Correction for P-factor
    Opposite rudder
  112. Action to correct for propeller torque
    Opposite aileron
  113. How many G's are required for a level 60 degree bank turn in a T-6 (or any aircraft)?
    +2.0G
  114. What control inputs are necessary for a coordinated level turn?
    Stick/Rudder in direction of turn, then neutral; Stick back; PCL forward
  115. Define Slip
    Insufficient rudder in direction of turn; Needle & ball on same side
  116. Define Skid
    Too much rudder in direction of turn; Needle & ball opposite sides
  117. Why must back pressure be added in a turn?
    To increase total lift
  118. Why must power be increased during a turn?
    Increased AOA, therefore increased induced drag, therefore increased power
  119. What factors limit the max bank angle and min turning velocity?
    Weight, Altitude, Load factor, Stall AOA, Engine performance, Wing loading
  120. What two things determine turn rate and radius?
    Velocity & angle of bank
  121. Define Turn radius
    Radius length of turn
  122. Define Turn rate
    Rate of heading change
  123. Define Load factor
    Load/weight
  124. Define Limit load factor
    Max load without damage
  125. Define Ultimate load factor
    Max load without failure (150o)
  126. Define Maneuvering speed
    Cornering velocity - max speed where abrupt inputs will not cause damage
  127. Define Asymmetric G's
    Aileron or rudder deflected while pulling G's
  128. What are the T-6 asymmetric load limits?
    -1.0 to 4.7
  129. What happens to load factor as bank increases?
    Increases
  130. Define Static stability (positive & negative)
    Initial tendency to move forward or away from original state

    • Positive- towards
    • Negative- away
  131. Define Dynamic stability
    Measurement of displacement over time after disturbance
  132. Define Sideslip angle
    Angle between longitudinal axis and flight path
  133. Define PIO (Pilot Induced Oscillations)
    Pilot and longitudinal stability correcting for oscillations simultaneously
  134. Describe directional static stability
    Stability of longitudinal axis around vertical axis
  135. Contrast stability and maneuverability
    More stable, less maneuverable

    Less stable, more maneuverable

    Inverse
  136. Describe boundary layer separation
    Point where airflow no longer adheres to wing
  137. Why does boundary layer separation occur?
    Decreasing kinetic energy; increasing adverse pressure gradient
  138. What is a stall?
    An increase in AOA results in a decrease in CL (coef of lift)
  139. Contrast airspeed and roll tendency between a power-on stall and a power-off stall
    • Power on: Lower speed, rolls left
    • Power off: High speed, rolls right
  140. What factors change stall airspeed?
    Weight, altitude, load factor
  141. How will the stall AOA change with an increase in weight?
    Doesn't (AOA never changes) - Stall speed increase
  142. How is the stall speed changed by a steeper bank angle?
    Increases
  143. What happens to stall speed when G's are increased?
    Increases
  144. In what order are the flight controls lost in a stall?
    • Aileron
    • Elevator
    • Rudder
  145. What is the function of leading edge slats?
    Suppress boundary layer separation
  146. Where does boundary layer separation move forward on the CL curve?
    Bend point before CL MAX
  147. Where does the stall occur on the Ccurve?
    CL MAX (stall region to right)
  148. What is the T-6 stall AOA?
    18 units
  149. What provides stall warning in the T-6?
    Stick shaker, AOA gauge
  150. When is the stick shaker activated?
    5-10 knots above stall speed
  151. What two factors are necessary for a spin?
    Stall and yaw
  152. Contrast lift and drag between a stalled aircraft and a spinning aircraft
    • Stalled: Equal lift & drag
    • Spin: Asymmetric lift & drag
  153. What is the cause of asymmetry?
    Yaw
  154. Describe an erect accelerated spin
    Stick other than full aft
  155. Why is a left spin different from a right spin?
    Gyroscopic effect of prop
  156. What is poststall gyration?
    Aerodynamic forces resulting in movement about the 3 axis
  157. What is the primary factor affecting poststall gyration intensity?
    Airspeed
  158. Describe asymmetric wing stall
    Uneven lift & drag (yaw) on opposite wings causes auto-rotation
  159. When the stick is full aft, what happens to the pitch of a spinning T-6? What happens to the rotation rate?
    • Pitch flattens
    • Rotation rate slows
  160. What is the primary difference between an inverted vs erect spin?
    • Inverted: Negative G's
    • Erect: Positive G's
  161. What are the characteristics of a right spin?
    Lower pitch (steeper), more oscillations, longer to stabilize, rotation rate increases
  162. Which flight control provides the greatest anti-slip force?
    Opposite rudder
  163. What factors affect wingtip vortex strength?
    Weight, speed, configuration
  164. What generates wake turbulence?
    Production of lift
  165. Which direction do wingtip vortices rotate?
    • Left: Clockwise
    • Right: Counter-Clockwise
  166. Describe the descent characteristics of wingtip vortices
    • Sink 400-500ft/min
    • Max sink 800-900ft/min
    • Last ~2min
  167. Which aircraft produce the strongest vortices?
    Heavy, clean, slow
  168. What are the hazards of wake turbulence?
    • Induced roll, induced flow field (downward)
    • Worst case: Loss of control
  169. When do wingtip vortices begin?
    At rotation
  170. When do wingtip vortices stop?
    Nosewheel down
  171. What is the minimum spacing when taking off behind a large or heavy aircraft?
    2 minutes
  172. When should you lift off/land behind a heavy aircraft?
    • T/O: Before rotation
    • LDG: Beyond nosewheel down
  173. Is wake turbulence from aircraft operation on other runways a hazard?
    Yes
  174. What effect would a 5 knot crosswind have on vortices?
    Can hold vortices on runway or blow to parallel runway (~5kt speed)
  175. What is minimum spacing when landing behind a large/heavy aircraft?
    • Large - 2min
    • Heavy - 3min
  176. What is minimum spacing around a hovering helicopter?
    3 rotor diameters
  177. What is your flight path and touchdown behind a landing heavy aircraft?
    • Flight path: Above
    • Touchdown: Beyond nosewheel touchdown
  178. What is wind shear?
    Sudden change in wind direction or speed
  179. Describe a decreasing performance wind shear
    • Lesser to greater tailwind OR
    • Greater to lesser headwind

    = Airspeed, pitch & VSI decrease
  180. Describe an increasing performance wind shear
    • Greater to lesser tailwind OR
    • Lesser to greater headwind

    = Airspeed, pitch & VSI increase
  181. What are the cockpit indications of flying through a microburst?
    Increasing performance windshear, downwash (VSI), decreasing performance windshear
  182. With a reported 5 knot loss, what adjustments should you make?
    T/O flaps, 5 knots add
  183. What is the maximum airspeed adjustment?
    10 knots
  184. A body at rest tends to remain at rest...
    Law of Equilibrium
  185. The measurement of the average kinetic energy of air particles is called
    Temperature
  186. What is the benefit of a tapered wing?
    Structural stiffness
  187. Law of interaction?
    For every action there is an equal and opposite reaction
  188. Which airfoil produces no lift at zero degrees angle of attack?
    Symmetric airfoil
  189. What is the benefit of geometric and aerodynamic twist on a wing?
    The wing root stalls before the wing tip
  190. Parasite drag is define as drag
    caused by anything other than the creation of lift
  191. In level flight an increase in velocity will
    decrease induced drag
  192. Ground effect is the phenomenon that reduces ___ due to a decrease in ___
    induced drag; downwash
  193. Thrust available ___ as a velocity increases for a prop driven aircraft
    Decreases
  194. As velocity increases, a propeller's PA will initially increase then
    Decrease
  195. To roll the airplane to the right
    Right aileron rises decreasing lift, left aileron lowers increasing lift
  196. For the nose of the airplane to pitch up, the
    trailing edge of the elevator must move up in relation to the horizontal stabilizer
  197. Increasing the camber of the wing
    increases lift
  198. The T-6A has which kind of trailing edge flags?
    Split flaps
  199. Aerodynamic force is the
    result of pressure and friction distribution over an airfoil
  200. A ___ airfoil produces lift at zero degrees AOA
    positively cambered
  201. Maximum excess power for a prop-driven aircraft occurs ____ L/DMAX
    at
  202. As altitude increases, power available _____
    decreases
  203. Takeoff distance can be reduced by
    increasing wing camber
  204. P-factor is caused by
    one prop blade creating more thrust than its opposing blade
  205. Asymmetric G limits are lower than symmetric because
    the lift on the up-going wing is experiencing more G than what is read on the accelerometer
  206. Neutral dynamic stability is
    oscillations never dampen but remain at a constant amplitude
  207. What is lateral stability?
    Generates forces that reduce the bank angle and returns to wings-level
  208. Cross-coupling causes
    spiral and directional divergence
  209. Max glide range is obtained by
    flying at L/DMAX
  210. Slipstream swirl is most noticeable
    at high power settings and low airspeed

What would you like to do?

Home > Flashcards > Print Preview