Chapter 7

Question 1

For a rotor system with no flapping offset and its rotational direction is anti-clockwise When the helicopter is in forward flight.
a) Indicate the direction of increment of the rotor thrust, forward/backward forces,
and rotor tilting angle (flapping motion) provided by pushing forward the longitudinal
cyclic pitch controller.

Answer 1

Higher rotor thrust, more backward forces, rotor tilt backwards

Question 2

For a rotor system with no flapping offset and its rotational direction is anti-clockwise. When the helicopter is in forward flight.
b) Indicating the direction of additional rotor thrust, forward/backward forces, and rotor
tilting angle (flapping motion) provided by introducing additional lateral cyclic pitch?

Answer 2

Sideward forces (direction: act as damping), rotor tilts sideward

Question 3

For a rotor system with no flapping offset and its rotational direction is anti-clockwise. When the helicopter is in forward flight.
C. Collective pitch influence on the rotor forward/backward forces and flapping direction.

Answer 3

Exaggerate the flapping motion, making the rotor tilt backwards and sidewards.

Question 4

For a rotor system with no flapping offset and its rotational direction is anti-clockwise. When the helicopter is in hover, and the rotor is not tilted backward or sideward
a) Vertical velocity influence on flapping motion

Answer 4

Not create any sideward tilt, and coning angle will be changed

Question 5

For a rotor system with no flapping offset and its rotational direction is anti-clockwise. When the helicopter is in hover, and the rotor is not tilted backward or sideward
b) If a man is walking from the cockpit to the tail part of the vehicle, how will the trim
control input, pitching attitude, rotor flapping, and tail rotor thrust change?

Answer 5

Collective pitching will be higher, additional nose-up pitching attitude, the longitudinal
cyclic pitch should be pushed forward, the rotor is flapping forward, and tail rotor thrust
will increase.

Question 6

For a sing-rotor helicopter configuration, they usually have a pre-setting angle. It means the rotor hub shaft tilts forward
When this helicopter is in hover flight, the trim pitching angle of this type of rotorcraft should
be (nose up/ nose down)

Answer 6

nose up

Question 7

For a sing-rotor helicopter configuration, they usually have a pre-setting angle. It means the rotor hub shaft tilts forward
Compared to the traditional rotor design with no pre-setting angle, how will the pitching
attitude and longitudinal cyclic change in the forward flight?

Answer 7

The pitching attitude will be more nose-up, and longitudinal cyclic control input will be more
backwards