C7 Flashcards
Rotor System with no flapping offset and anti clockwise rotation:
Helicopter is in forward flight.
Indicate the direction of increment of the rotor thrust, forward/backward forces,
and rotor tilting angle (flapping motion) provided by pushing backwards the
longitudinal cyclic pitch controller.
Higher rotor thrust, more backwards forces, rotor tilts backwards
Rotor System with no flapping offset and anti clockwise rotation:
Helicopter is in forward flight.
Indicate the direction of increment of the rotor thrust, forward/backward forces,
and rotor tilting angle (flapping motion) provided by introducing additional lateral cyclic pitch?
Sidewards forces (acts as damping), rotor tilts sideward
Rotor system with no flapping offset and anticlockwise rotation:
Helicopter in forward flight
Collective pitch influence on the rotor forward/backward forces and flapping direction.
Exaggerate flapping motion making rotor tilt backwards or sidewards
When the helicopter is in hover, and the rotor is not tilted backward or sideward
Vertical velocity influence on flapping motion ?
Doesn’t create any sidewards tilt, coning angle is changed
When the helicopter is in hover, and the rotor is not tilted backward or sideward
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?
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.
For a single-rotor helicopter configuration, they usually have a pre-setting angle which 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)?
Nose-up
For a single-rotor helicopter configuration, they usually have a pre-setting angle which 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?
The pitching attitude will be more nose-up, and longitudinal cyclic control input will be more
backwards
For a single-rotor helicopter configuration, they usually have a pre-setting angle which means the rotor hub shaft tilts forward
From the view of safety and performance, what are the benefits of this design
The pitching attitude angle is closer to zero in high-speed flight, giving pilots a better view
The pitching attitude is closer to zero, which can reduce the drag provided by the fuselage.
