Aircraft Control Surfaces and Forces of Flight Guide

1. Private Pilot Ground School Loren French CFII/MEI/ATP Alpine Flight Training AlpineFlightTraining.com

2. Aircraft Control Surfaces

3. Flaps • Flaps increase lift and create drag allowing a greater rate of decent without increasing airspeed. • Flaps are located on the trailing edge of the wing.

4. Aileron • Ailerons bank the aircraft along the longitudinal axis by inducing greater lift. • Connected to the yoke via cables and pulley's. • Located on the outboard trailing edge of the wing

5. Rudder • Rudder controls the direction of the aircraft about the yaw axis. • Connected to the Rudder pedals via cable and pulleys. • Rudder is located on the trailing edge of the vertical stabilizer.

6. Elevator • The Elevator controls the pitch attitude of the aircraft about the lateral axis • Connected to the Yoke via cable and pulleys. • Located on the trailing edge of the horizontal stabilizer • Usually adjusted with Elevator Trim Tabs.

7. Four Forces of Flight • Lift-Upward • Thrust-Forward • Weight-Downward • Drag-Backward • All forces are equal in straight and level flight.

8. Stalls • A stall occurs when the Critical Angle of Attack has been exceeded. • The Critical Angle of Attack is when the air can no longer flow over the top of the wing and lift diminished.

9. Spins • A spin occurs when one wing is less stalled than the other. • A plane must be stalled in order to spin

10. Ground Effect • Airplanes experience Ground Effect approximately one wing length from the surface. • Ground effect increases lift without corresponding drag increase • Ground effect causes the aircraft to float longer during landing • Ground effect can also cause an aircraft to become airborne before proper takeoff airspeed has been acquired.

11. Turns in an Airplane • Banking the aircraft creates a Horizontal Component of Lift. • The Rudder and Aileron are used to maintain coordinated turn and eliminate adverse yaw.

12. Aircraft Stability • Inherently stable aircraft will return to to straight and level flight. • Center of Gravity affects longitudinal stability of the aircraft. • Rearward CG=less stable/more maneuverable, difficult to recover from a stall, shorter take off roll, more efficient. • Forward CG= more stable/less maneuverable, harder to flare for landing, longer takeoff roll, less efficient.

13. Aircraft Stability • CG is always forward of the Center of Lift • Horizontal stabilizer creates a downward lifting action.

14. LEFT TURNING TENDENCIES

15. Torque • Newton's third law- For every action there is an equal and opposite reaction. • Greatest at- Low Airspeeds, High Power settings, High Angles of Attack [takeoff]

16. P-Factor • Yawing tendency due to asymmetrical propeller loading. • At high angles of attack the descending blade has more “bite”, providing more thrust. • Creates a adverse yaw to the left that must be corrected with right rudder input

17. Propeller Slipstream • Effect of the airflow created by the spinning propeller striking the tail of the aircraft. • Causes aircraft to Yaw Left

18. Gyroscopic Precession • Reaction of a gyroscope in motion. • Force is felt 90 degrees ahead of the direction of rotation. • Creates a left yawing tendency, especially noticeable in tail wheel aircraft

19. LOAD FACTOR • Additional weight carried by the wings due to centrifugal force. • Load Factor can increase stall speed. • As Bank angle increases load factor increases