1. Stability for Straight and Level Flight
Gliders in Flight
Stability for Straight and Level Flight
Aerospace Engineering
© 2011 Project Lead The Way, Inc.

2. Glider in Flight

3. Gliders As Long Distance Fliers

4. Gaining Altitude Gliders do not have an engine
Gliders use rising air to gain altitude

5. Balsa Glider Flight
Straight and Level = Maximum Distance

6. Tree Axis of Movement

7. Movement in Yaw

8. Movement in Roll

9. Movement in Pitch

10. Static Stability

11. Dynamic Stability

12. Lateral Stability: Roll
High wing aircraft are naturally stabilizing

13. Lateral Stability: Dihedral

14. Why Does Dihedral Work?

15. Why Does Dihedral Work?
Uniform Lift
Weight

16. Why Does Dihedral Work?
Weight
Component of Weight
Causing a Sideslip

17. Why Does Dihedral Work? Rolling Lower Lift Moment Higher Lift
Lower AOA
Higher AOA
Induced Relative Wind

18. Lateral Stability: Types of Dihedral
No Dihedral
Straight Dihedral
Tip Dihedral
Polyhedral

19. Movement in Yaw

20. Directional Stability: Keel Effect

21. Directional Stability: Weather Vaning

22. Directional Stability: Moment Arms

23. Directional Stability

24. Movement in Pitch

25. Avoiding the Stalling

26. Weight and Balance Center of Lift Weight at Center of Gravity
Balanced, but easy to shift…
VERY nose heavy!
VERY tail heavy!
Weight at Center of Gravity

27. Center of Gravity Range