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Basic Aerodynamics III Stability Controls

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Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •To insure an airplane has good handling qualities in all flight regimes, we need it to be STABLE, MANEUVERABLE, and CONTROLLABLE •STABILITY is the characteristic of an airplane in flight that causes it to return to a condition of equilibrium, or steady flight, after it is disturbed. 09/25/14 Author: Harry L. Whitehead 1
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •To insure an airplane has good handling qualities in all flight regimes, we need it to be STABLE, MANEUVERABLE, and CONTROLLABLE •MANEUVERABLILITY is the characteristic that permits the pilot to easily move the airplane about its axes and to withstand the stress from these moves 09/25/14 Author: Harry L. Whitehead 2
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •To insure an airplane has good handling qualities in all flight regimes, we need it to be STABLE, MANEUVERABLE, and CONTROLLABLE •CONTROLLABILITY is the capability to respond to the pilot’s control inputs 09/25/14 Author: Harry L. Whitehead 3
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •Unfortunately, these characteristics are at odds with each other •Increase in one leads to a decrease in another • = all airplane designs are compromises •If make it too stable = it’s hard to control 09/25/14 Author: Harry L. Whitehead 4
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •2 TYPES OF STABILITY •STATIC •The ability of an object to return to its equilibrium state after being disturbed •DYNAMIC •The way the object moves after being disturbed 09/25/14 Author: Harry L. Whitehead 5
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •3 CONDITIONS OF STABILITY: •POSITIVE •The disruption of an object gets less over time •NEGATIVE •The disruption gets greater over time •NUETRAL •The disruption neither increases or decreases over time 09/25/14 Author: Harry L. Whitehead 6
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •Positive Stability: •The tendency to return to the original equilibrium •Example: Ball in a trough •Generally desirable in an airplane but does decrease maneuverability 09/25/14 Author: Harry L. Whitehead 7
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •Negative Stability: •The tendency to move away from the equilibrium •Example: Ball on a hill •Undesirable in an airplane 09/25/14 Author: Harry L. Whitehead 8
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •Nuetral Stability: •The tendency for the correcting forces to neither increase or decrease over time •Example: Ball on a flat surface •Somewhat OK in an airplane 09/25/14 Author: Harry L. Whitehead 9
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •Since we have 3 main axes of an aircraft, we also have 3 main types of Stability: •LONGITUDINAL •LATERAL •DIRECTIONAL 09/25/14 Author: Harry L. Whitehead 10
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •Is the ability of an aircraft to remain stable ABOUT (OR AROUND) THE LATERAL AXIS •Is PITCH STABILITY •Or keeping the Longitudinal Axis stable 09/25/14 Author: Harry L. Whitehead 11
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •Since the CENTER OF PRESSURE (or CENTER OF LIFT) moves with Angle of Attack changes 09/25/14 Author: Harry L. Whitehead 12
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •We need to be sure the Center of Gravity doesn’t get behind the Center of Pressure or severe flight problems will occur (such as can’t lower the nose) 09/25/14 Author: Harry L. Whitehead 13
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •Airplanes are designed so the Center of Pressure or Lift is behind of the Center of Gravity = a downward pitching moment on the nose of the aircraft at all times 09/25/14 Author: Harry L. Whitehead 14
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •This, coupled with the downward TAIL LOAD created by the HORIZONTAL STABILIZER, create a balanced set of conditions to keep the Longitudinal Axis stable 09/25/14 Author: Harry L. Whitehead 15
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •If the aircraft gets disturbed so the nose goes up, the Horizontal Stabilizer’s Angle of Attack is decreased and creates less Down Load to compensate •Hor. Stabs. are usually symmetrical airfoils 09/25/14 Author: Harry L. Whitehead 16
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •If the aircraft gets disturbed so the nose goes down, the Horizontal Stabilizer’s Angle of Attack is increased and creates more Down Load to compensate •This is Positive Longitudinal Stability 09/25/14 Author: Harry L. Whitehead 17
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •The Horizontal Stabilizer will be installed at some particular Angle of Incidence so it can do its job correctly •This may be negative, positive, or zero 09/25/14 Author: Harry L. Whitehead 18
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Is the ability of an aircraft to remain stable ABOUT (OR AROUND) THE LONGITUDINAL AXIS •Is ROLL STABILITY •Or keeping the Lateral Axis stable 09/25/14 Author: Harry L. Whitehead 19
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •This is the upward angle between the wing and the Lateral Axis 09/25/14 Author: Harry L. Whitehead 20
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •As an airplane is upset so a wing drops, it starts to SIDESLIP toward the low wing 09/25/14 Author: Harry L. Whitehead 21
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •This slipping motion plus the downward movement of the wing add downward vectors to the Angle of Attack production and lead to an increase in a on the lower wing = more lift on that wing 09/25/14 Author: Harry L. Whitehead 22
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •On the wing moving up, the upward vector reduces the a = less lift 09/25/14 Author: Harry L. Whitehead 23
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •These two changes to lift create a rolling force in the direction to restore the wings to level = Positive Lateral Stability 09/25/14 Author: Harry L. Whitehead 24
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •A HIGH-WING Airplane will not need as much Dihedral as a LOW-WING Airplane •since the Center of Gravity is below the Center of Lift it tends to right itself naturally (it’s inherently more Laterally Stable) Author: Harry L. Whitehead 25
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Is the ability of an aircraft to remain stable ABOUT (OR AROUND) THE VERTICAL AXIS •Is YAW STABILITY •Or keeping the Vertical Axis stable 09/25/14 Author: Harry L. Whitehead 26
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Provided by the VERTICAL STABILIZER and Fuselage •To be Directionally Stable, an aircraft must have more surface area behind the CG than in front so it acts like a Weather Vane 09/25/14 Author: Harry L. Whitehead 27
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Provided by the VERTICAL STABILIZER and Fuselage •When the aircraft yaws (= SIDESLIP), the Vert. Stab. creates lift in the restoring direction and the sides of the fuselage offer a surface for the wind to push against 09/25/14 Author: Harry L. Whitehead 28
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Is also improved by SWEEPBACK of the wings 09/25/14 Author: Harry L. Whitehead 29
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Is also improved by SWEEPBACK of the wings •When yawing (SIDESLIP), the wing which is moving forward has a larger effective wing area = more drag to push it back 09/25/14 Author: Harry L. Whitehead 30
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •If the aircraft’s wing drops it will tend to yaw into the low wing and the dihedral and sweepback will combine to return the wings to level quickly 09/25/14 Author: Harry L. Whitehead 31
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •As the low wing moves up the Lateral Stability will return the aircraft to straight flight = the low wing will be moving faster than the high wing = more lift 09/25/14 Author: Harry L. Whitehead 32
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •= that wing will now rise and the process will repeat in the opposite direction 09/25/14 Author: Harry L. Whitehead 33
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •The resulting low level oscillation (“Dutch Roll”) doesn’t affect aircraft flight safety but is uncomfortable for passengers 09/25/14 Author: Harry L. Whitehead 34
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •Aircraft susceptible to this usually have YAW DAMPERS connected to the rudder controls to automatically apply corrective rudder action 09/25/14 Author: Harry L. Whitehead 35
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Large aircraft, like small, control the aircraft about the same 3 axes: Lateral, Longitudinal, and Vertical •Major differences: •More control surfaces •Hydraulic actuated •Power-boosted •Hydraulic cylinder in parallel with control rods •Pilot moves surface and valve to actuate hydraulic cylinder to help 09/25/14 Author: Harry L. Whitehead 36
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Large aircraft, like small, control the aircraft about the same 3 axes: Lateral, Longitudinal, and Vertical •Major differences: •More control surfaces •Hydraulic actuated •Power-boosted •Boosting is typically about 14:1 ratio •Disadvantage: in transonic speed range shock waves form on controls and cause buffeting which is fed back into cockpit 09/25/14 Author: Harry L. Whitehead 37
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Large aircraft, like small, control the aircraft about the same 3 axes: Lateral, Longitudinal, and Vertical •Major differences: •More control surfaces •Hydraulic actuated •Irreversibles •Used to keep buffet from reaching cockpit •Hyd. Cylinders in series with control rods •Also need “feedback” system to give pilot the feel of the controls 09/25/14 Author: Harry L. Whitehead 38
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 09/25/14 Author: Harry L. Whitehead 39
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Uses Irreversible system with 2 separate hydraulic systems, Standby system, and manual backup of Primary Controls (servo tabs) •Example: Boeing 727 09/25/14 Author: Harry L. Whitehead 40
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Roll •Ailerons and Spoilers •4 ailerons and 14 spoilers 09/25/14 Author: Harry L. Whitehead 41
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Roll •Inboard ailerons and 10 flight spoilers do high speed flight with outboard ailerons locked in neutral position 09/25/14 Author: Harry L. Whitehead 42
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Roll •When trailing edge flaps are deployed, outboard ailerons unlocked = all ailerons and flight spoilers work 09/25/14 Author: Harry L. Whitehead 43
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Pitch •Elevators for normal pitch action •Movable Horizontal Stab. for trim action 09/25/14 Author: Harry L. Whitehead 44
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Yaw •2 independent rudders with anti-balance (anti-servo) tabs 09/25/14 Author: Harry L. Whitehead 45
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Yaw •Also receives input from the Yaw Dampers to counteract Dutch Roll 09/25/14 Author: Harry L. Whitehead 46
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Auxiliary Lift Devices: Trailing Edge Flaps •Triple-slotted Fowler Flaps •Take-off = only back, Landing = back and down 09/25/14 Author: Harry L. Whitehead 47
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Auxiliary Lift Devices: Leading Edge Flaps •Krueger-type •Increase area and camber 09/25/14 Author: Harry L. Whitehead 48
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Auxiliary Lift Devices: Leading Edge Slats •Increase camber •Inboard flaps stall first = retain aileron control 09/25/14 Author: Harry L. Whitehead 49
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •Ailerons have Balance Tabs which also act as Trim Tabs 09/25/14 Author: Harry L. Whitehead 50
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •Elevators have Servo Tabs which also act as Trim Tabs 09/25/14 Author: Harry L. Whitehead 51
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •Rudders have Anti-balance (anti-servo) Tabs which also act as Trim Tabs 09/25/14 Author: Harry L. Whitehead 52
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •These Tabs also serve as manual backups in case of total hydraulic failure 09/25/14 Author: Harry L. Whitehead 53
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 747 09/25/14 Author: Harry L. Whitehead 54
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 757 09/25/14 Author: Harry L. Whitehead 55
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Lockheed L-1011 09/25/14 Author: Harry L. Whitehead 56
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Airbus A320 09/25/14 Author: Harry L. Whitehead 57
Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Controls 09/25/14 Author: Harry L. Whitehead 58

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Basic Aerodynamics III Stability Controls

  • 1. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •To insure an airplane has good handling qualities in all flight regimes, we need it to be STABLE, MANEUVERABLE, and CONTROLLABLE •STABILITY is the characteristic of an airplane in flight that causes it to return to a condition of equilibrium, or steady flight, after it is disturbed. 09/25/14 Author: Harry L. Whitehead 1
  • 2. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •To insure an airplane has good handling qualities in all flight regimes, we need it to be STABLE, MANEUVERABLE, and CONTROLLABLE •MANEUVERABLILITY is the characteristic that permits the pilot to easily move the airplane about its axes and to withstand the stress from these moves 09/25/14 Author: Harry L. Whitehead 2
  • 3. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •To insure an airplane has good handling qualities in all flight regimes, we need it to be STABLE, MANEUVERABLE, and CONTROLLABLE •CONTROLLABILITY is the capability to respond to the pilot’s control inputs 09/25/14 Author: Harry L. Whitehead 3
  • 4. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General •Unfortunately, these characteristics are at odds with each other •Increase in one leads to a decrease in another • = all airplane designs are compromises •If make it too stable = it’s hard to control 09/25/14 Author: Harry L. Whitehead 4
  • 5. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •2 TYPES OF STABILITY •STATIC •The ability of an object to return to its equilibrium state after being disturbed •DYNAMIC •The way the object moves after being disturbed 09/25/14 Author: Harry L. Whitehead 5
  • 6. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •3 CONDITIONS OF STABILITY: •POSITIVE •The disruption of an object gets less over time •NEGATIVE •The disruption gets greater over time •NUETRAL •The disruption neither increases or decreases over time 09/25/14 Author: Harry L. Whitehead 6
  • 7. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •Positive Stability: •The tendency to return to the original equilibrium •Example: Ball in a trough •Generally desirable in an airplane but does decrease maneuverability 09/25/14 Author: Harry L. Whitehead 7
  • 8. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •Negative Stability: •The tendency to move away from the equilibrium •Example: Ball on a hill •Undesirable in an airplane 09/25/14 Author: Harry L. Whitehead 8
  • 9. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: General Types •Nuetral Stability: •The tendency for the correcting forces to neither increase or decrease over time •Example: Ball on a flat surface •Somewhat OK in an airplane 09/25/14 Author: Harry L. Whitehead 9
  • 10. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •Since we have 3 main axes of an aircraft, we also have 3 main types of Stability: •LONGITUDINAL •LATERAL •DIRECTIONAL 09/25/14 Author: Harry L. Whitehead 10
  • 11. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •Is the ability of an aircraft to remain stable ABOUT (OR AROUND) THE LATERAL AXIS •Is PITCH STABILITY •Or keeping the Longitudinal Axis stable 09/25/14 Author: Harry L. Whitehead 11
  • 12. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •Since the CENTER OF PRESSURE (or CENTER OF LIFT) moves with Angle of Attack changes 09/25/14 Author: Harry L. Whitehead 12
  • 13. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •We need to be sure the Center of Gravity doesn’t get behind the Center of Pressure or severe flight problems will occur (such as can’t lower the nose) 09/25/14 Author: Harry L. Whitehead 13
  • 14. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •Airplanes are designed so the Center of Pressure or Lift is behind of the Center of Gravity = a downward pitching moment on the nose of the aircraft at all times 09/25/14 Author: Harry L. Whitehead 14
  • 15. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •This, coupled with the downward TAIL LOAD created by the HORIZONTAL STABILIZER, create a balanced set of conditions to keep the Longitudinal Axis stable 09/25/14 Author: Harry L. Whitehead 15
  • 16. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •If the aircraft gets disturbed so the nose goes up, the Horizontal Stabilizer’s Angle of Attack is decreased and creates less Down Load to compensate •Hor. Stabs. are usually symmetrical airfoils 09/25/14 Author: Harry L. Whitehead 16
  • 17. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •If the aircraft gets disturbed so the nose goes down, the Horizontal Stabilizer’s Angle of Attack is increased and creates more Down Load to compensate •This is Positive Longitudinal Stability 09/25/14 Author: Harry L. Whitehead 17
  • 18. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LONGITUDINAL STABILITY •The Horizontal Stabilizer will be installed at some particular Angle of Incidence so it can do its job correctly •This may be negative, positive, or zero 09/25/14 Author: Harry L. Whitehead 18
  • 19. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Is the ability of an aircraft to remain stable ABOUT (OR AROUND) THE LONGITUDINAL AXIS •Is ROLL STABILITY •Or keeping the Lateral Axis stable 09/25/14 Author: Harry L. Whitehead 19
  • 20. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •This is the upward angle between the wing and the Lateral Axis 09/25/14 Author: Harry L. Whitehead 20
  • 21. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •As an airplane is upset so a wing drops, it starts to SIDESLIP toward the low wing 09/25/14 Author: Harry L. Whitehead 21
  • 22. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •This slipping motion plus the downward movement of the wing add downward vectors to the Angle of Attack production and lead to an increase in a on the lower wing = more lift on that wing 09/25/14 Author: Harry L. Whitehead 22
  • 23. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •On the wing moving up, the upward vector reduces the a = less lift 09/25/14 Author: Harry L. Whitehead 23
  • 24. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •Provided mostly by wing DIHEDRAL •These two changes to lift create a rolling force in the direction to restore the wings to level = Positive Lateral Stability 09/25/14 Author: Harry L. Whitehead 24
  • 25. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •LATERAL STABILITY •A HIGH-WING Airplane will not need as much Dihedral as a LOW-WING Airplane •since the Center of Gravity is below the Center of Lift it tends to right itself naturally (it’s inherently more Laterally Stable) Author: Harry L. Whitehead 25
  • 26. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Is the ability of an aircraft to remain stable ABOUT (OR AROUND) THE VERTICAL AXIS •Is YAW STABILITY •Or keeping the Vertical Axis stable 09/25/14 Author: Harry L. Whitehead 26
  • 27. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Provided by the VERTICAL STABILIZER and Fuselage •To be Directionally Stable, an aircraft must have more surface area behind the CG than in front so it acts like a Weather Vane 09/25/14 Author: Harry L. Whitehead 27
  • 28. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Provided by the VERTICAL STABILIZER and Fuselage •When the aircraft yaws (= SIDESLIP), the Vert. Stab. creates lift in the restoring direction and the sides of the fuselage offer a surface for the wind to push against 09/25/14 Author: Harry L. Whitehead 28
  • 29. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Is also improved by SWEEPBACK of the wings 09/25/14 Author: Harry L. Whitehead 29
  • 30. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •Is also improved by SWEEPBACK of the wings •When yawing (SIDESLIP), the wing which is moving forward has a larger effective wing area = more drag to push it back 09/25/14 Author: Harry L. Whitehead 30
  • 31. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •If the aircraft’s wing drops it will tend to yaw into the low wing and the dihedral and sweepback will combine to return the wings to level quickly 09/25/14 Author: Harry L. Whitehead 31
  • 32. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •As the low wing moves up the Lateral Stability will return the aircraft to straight flight = the low wing will be moving faster than the high wing = more lift 09/25/14 Author: Harry L. Whitehead 32
  • 33. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •= that wing will now rise and the process will repeat in the opposite direction 09/25/14 Author: Harry L. Whitehead 33
  • 34. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •The resulting low level oscillation (“Dutch Roll”) doesn’t affect aircraft flight safety but is uncomfortable for passengers 09/25/14 Author: Harry L. Whitehead 34
  • 35. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Aircraft Stability Controls •Stability: About the Aircraft Axes •DIRECTIONAL STABILITY •But sweepback can cause a small problem: Dutch Roll •Aircraft susceptible to this usually have YAW DAMPERS connected to the rudder controls to automatically apply corrective rudder action 09/25/14 Author: Harry L. Whitehead 35
  • 36. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Large aircraft, like small, control the aircraft about the same 3 axes: Lateral, Longitudinal, and Vertical •Major differences: •More control surfaces •Hydraulic actuated •Power-boosted •Hydraulic cylinder in parallel with control rods •Pilot moves surface and valve to actuate hydraulic cylinder to help 09/25/14 Author: Harry L. Whitehead 36
  • 37. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Large aircraft, like small, control the aircraft about the same 3 axes: Lateral, Longitudinal, and Vertical •Major differences: •More control surfaces •Hydraulic actuated •Power-boosted •Boosting is typically about 14:1 ratio •Disadvantage: in transonic speed range shock waves form on controls and cause buffeting which is fed back into cockpit 09/25/14 Author: Harry L. Whitehead 37
  • 38. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Large aircraft, like small, control the aircraft about the same 3 axes: Lateral, Longitudinal, and Vertical •Major differences: •More control surfaces •Hydraulic actuated •Irreversibles •Used to keep buffet from reaching cockpit •Hyd. Cylinders in series with control rods •Also need “feedback” system to give pilot the feel of the controls 09/25/14 Author: Harry L. Whitehead 38
  • 39. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 09/25/14 Author: Harry L. Whitehead 39
  • 40. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Uses Irreversible system with 2 separate hydraulic systems, Standby system, and manual backup of Primary Controls (servo tabs) •Example: Boeing 727 09/25/14 Author: Harry L. Whitehead 40
  • 41. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Roll •Ailerons and Spoilers •4 ailerons and 14 spoilers 09/25/14 Author: Harry L. Whitehead 41
  • 42. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Roll •Inboard ailerons and 10 flight spoilers do high speed flight with outboard ailerons locked in neutral position 09/25/14 Author: Harry L. Whitehead 42
  • 43. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Roll •When trailing edge flaps are deployed, outboard ailerons unlocked = all ailerons and flight spoilers work 09/25/14 Author: Harry L. Whitehead 43
  • 44. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Pitch •Elevators for normal pitch action •Movable Horizontal Stab. for trim action 09/25/14 Author: Harry L. Whitehead 44
  • 45. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Yaw •2 independent rudders with anti-balance (anti-servo) tabs 09/25/14 Author: Harry L. Whitehead 45
  • 46. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Primary Controls: Yaw •Also receives input from the Yaw Dampers to counteract Dutch Roll 09/25/14 Author: Harry L. Whitehead 46
  • 47. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Auxiliary Lift Devices: Trailing Edge Flaps •Triple-slotted Fowler Flaps •Take-off = only back, Landing = back and down 09/25/14 Author: Harry L. Whitehead 47
  • 48. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Auxiliary Lift Devices: Leading Edge Flaps •Krueger-type •Increase area and camber 09/25/14 Author: Harry L. Whitehead 48
  • 49. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Auxiliary Lift Devices: Leading Edge Slats •Increase camber •Inboard flaps stall first = retain aileron control 09/25/14 Author: Harry L. Whitehead 49
  • 50. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •Ailerons have Balance Tabs which also act as Trim Tabs 09/25/14 Author: Harry L. Whitehead 50
  • 51. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •Elevators have Servo Tabs which also act as Trim Tabs 09/25/14 Author: Harry L. Whitehead 51
  • 52. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •Rudders have Anti-balance (anti-servo) Tabs which also act as Trim Tabs 09/25/14 Author: Harry L. Whitehead 52
  • 53. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 727 •Secondary Controls (Tabs): •These Tabs also serve as manual backups in case of total hydraulic failure 09/25/14 Author: Harry L. Whitehead 53
  • 54. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 747 09/25/14 Author: Harry L. Whitehead 54
  • 55. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Boeing 757 09/25/14 Author: Harry L. Whitehead 55
  • 56. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Lockheed L-1011 09/25/14 Author: Harry L. Whitehead 56
  • 57. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Large Aircraft Controls Controls •Example: Airbus A320 09/25/14 Author: Harry L. Whitehead 57
  • 58. Basic Aerodynamics III. Basic Aerodynamics A. The Atmosphere B. Physics C. The Airfoil D. Lift & Drag E. Stability F. Large Aircraft Flight Controls 09/25/14 Author: Harry L. Whitehead 58