Basic Aerodynamics and Stability

1. Basic Aerodynamics and Stability Presented by: Mr Jamie Presser

2. Topic: Overview of basic aerodynamics, flight controls and effects of Centre of Gravity on stability

3. Definition of Controlled Flight Controlled Flight is: • Provide corrections • Cause movement in the desired direction The ability to produce movements about the various axis that,

4. Aerodynamic Terms Chord line: • Line running from the leading edge point of min radius to trailing edge Chord: • Length of Chord line

5. Aerodynamic Terms Mean camber line: • Line running half way between upper and lower surface of aerofoil Camber: • Distance between chord line and mean camber line

6. Angle Relative Airflow Aerodynamic Terms CoP Angle of Attack • Angle between chord line and Relative airflow Centre of Pressure (CoP) • Point where all aerodynamic pressures can be represented as a single vector Chord Line

7. Bernoulli's Theorem Given: Total Pressure = P0 Static Pressure = P1 Dynamic Pressure = P2 P0 = P1 + P2

8. Air Flow Restriction Bernoulli's Theorem P0 = P1 + P2 Lower static pressure Higher static pressure

9. Thrust Aileron Aileron Primary Flight Controls Rudder Elevator

10. Control movement Elevator • Primary Response = Change in Pitch • Secondary Response = Change in Speed

11. Control Movement Ailerons • Primary Response = Roll • Secondary Response = Yaw

12. Control Movement Rudder • Primary Response = Yaw • Secondary Response = Roll

13. Payload Naturally stable Unstable – Not recommended Payload Aft of CoG Aircraft balanced with payload fitted – Nose down tendency on release Aircraft balanced without payload fitted – Unstable until payload released

14. Naturally stable Unstable Not recommended Payload Forward of CoG Payload Aircraft balanced without payload fitted – Nose down tendency until release Aircraft balanced with payload fitted – Unstable when payload released

15. Payload No change on payload release Ideal Payload At CoG

16. Predator Global Hawk Shadow Avitus - Petrel Jindivick Reaper Boeing X-37 Heron Fire Scout

17. Any Questions?