Helicopter theory class review

5. Distance between the blade tip and the center of the mast.
6. It is the geometric locus of points equidistant from the upper and lower surfaces.
7. Axis of rotation.
8. Perpendicular to the no flapping axis.
9. Angle between the drive axis and the no flapping axis.
10. It is the acute angle between the chord line of the airfoil and the relative wind.
13. Applied force manifested 90 degrees later in the direction of rotation from where the force was applied.
18. Any surface designed to obtain a useful reaction, or lift, from air passing over it.
20. Force which tends to resist the airfoil’s passage through the air.
22. A heavier-than-air flying machine that is supported in the air by aerodynamic lift produced by an engine-driven rotor.
23. Tthe angular difference between the chord of the blade and the reference plane.

1. Protect leading edge from abrasion.
2. Alternation from hover to forward flight and forward flight to hover.
3. Imaginary line which goes through the tip and the blade root.
4. Perpendicular to the mast.
5. Solution to reduce vertical bending moment.
11. Angle between the blade and the drive plane.
12. Uneven amount of lift on opposite sides of the rotor disc.
14. Straight-line distance across an airfoil from leading edge to trailling edge.
15. Imaginary point where the result of all the aerodynamic forces of the airfoil are considered to be concentrated.
16. perpendicular to the driving section.
17. Point of an object at which all of the weight is considered to be concentrated.
19. Circle described by the blade tips.
20. Axis of the mast.
21. Force produced by the airfoil that is perpendicular to the relative wind and opposes gravity.
22. Condition of helicopter flight in which the machine holds a fixed position over the earth.