by p1l0t


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Front Back
Primary Flight Controls
  • Directly Control aircraft
  • Provide pilot with feel
  • Provide movement around the 3 axes
Pitch
  • Movement OF Longitudinal Axis ABOUT the Lateral Axis
  • Elevator/Stabilator
Roll
  • Movement OF Lateral Axis ABOUT the Longitudinal Axis
  • Ailerons
Ailerons
Left Turn, Left Rises, Differential Lift
Adverse Yaw
  • Increased Lift of Downward Aileron
  • Drag also increases, tendency to yaw to outside of turn
Types of Ailerons
Methods of Reducing Adverse Yaw
  • Differential
  • Frise
Differential Ailerons
Up aileron moves twice as far as down aileron
Frise Aileron
  • Aileron goes up, leading edge of aileron goes down into wind (increasing drag)
  • Slotted: lowered aileron is more effective at high AOA
  • Differential on some Frise
Yaw
  • Movement about the vertical Axis
  • Rudder
Rudder
  • Used to maintain coordinated flight
  • Pedals turn nose wheel on ground
Secondary Flight Controls
Improves Performance Characteristics of Aircraft
  • Flaps
  • Leading Edge Devices
  • Spoilers
Flaps
  • Increases: Lift, Induced Drag, Critical AOA
  • Allows: Landing at slower airspeed and steeper angle of descent without increasing airspeed
Types of Flaps
  • Plain
  • Split
  • Slotted
  • Fowler
Plain Flaps
  • Increases Camber which increases CL
  • Increases Drag, moves center of pressure aft
  • Nose Down pitching moment
Split Flaps
  • Slightly Greater lift than plain
  • More drag and turbulent air pattern
  • Smallest pitching moment
Slotted Flaps
  • Increases CL much more than plain/split
  • High energy air ducted to top, accelerates boundry layer and delays airflow separation
Fowler Flaps
  • Increases wing area and camber
  • Small increase in drag for large increase in lift
Slotted Fowler
  • Last extension of fowler flaps
  • Increases drag with little increase in lift
Types of Leading Edge Devices
  • Fixed Slot
  • Movable Slot
  • Leading Edge Flaps
  • Leading Edge Cuffs
Fixed Slot
  • Delays airflow at higher AOA
  • No increase in camber, but increase in CL Max
  • Delays separation
Movable Slot
  • Flush at low AOA, slides forward at higher AOA
  • Delays airflow separation
Leading Edge Flaps
  • Increases CL Max and Camber
  • Small increment gives greatest L/D ratio (like all flaps)
Leading Edge Cuffs
  • Extends leading edge down and forward
  • Air attaches better to upper surface at high AOA
  • Increase CLMAX and Camber
  • Fixed, drag penalty at cruise
Spoilers
  • Decrease Lift, Increase Drag
  • Descend without increasing Airspeed
  • Reduces ground rollout
Trim
Used to relieve pilot of excess control forces
Types of Trim
  • Trim Tabs
  • Balance Tabs
  • Anti-Servo
  • Ground Adjustable Tabs
  • Adjustable Stabilizer
Trim Tabs
Nose up, Trim tab down
Balance Tabs
  • Automatically moves in opposite direction
  • For aircraft with excessively high control surfaces
Anti-Servo
  • Automatically moves in same direction as control surface
  • Decreases sensitivity on stabilators
Ground Adjustable Tabs
Non-Movable bent tabs (trial and error)
Adjustable Stabilizer
Linkages pivot horizontal stabilizer (still has elevator)
x of y cards