CADH Practice Cards 5 Flashcards
Random questions/statements for exam preparation
Flapping to equality means…
Allowing the blades to flap of thier own accord, increasing and decreasing pitch angles by the adjustment of induced flow to increase and decrease lift respectively.
Rotational airflow is..
Airflow due to the actual rotation of the blade, parallel to the plane of rotation.
The relative wind angle that will produce weathercocking is….
180 degrees.
Raising the collective will….
Collectivly change the pitch (and equal amount) relative to the rotor hub.
Aircraft designers can incorporate a feature into the blade design to prolong the effect of comressibility, this is known as…
Swept back tips
Three benifits of a flare are…
Decrease ROD, decrease FWD airspeed and Increase RRPM
Hovering in ground effect (HIGE) would be most useful when…
hovering at high density altitudes with high AUW
Ref: Principles of Helicopter Flight, Chapter 11, pg. 81
A one-per-rev vertical vibration can be caused by a…
Out of track main rotor.
Principles of Helicopter Flight, Chapter 20
Two indicators of a sudden increase in headwind during approach to land would be….
an increase in indicated airspeed and a decrease in rate of descent.
When the angle of attack increases, drag increases and lift decreases.
True or False?
False
Induced drag at the blade tip is know as…..
Vortices
In relation to aerodynamics, high air density can….
increase engine power, increase thrust and increase lift.
Assuming all other factors are equal, a decrease in airspeed will require an increase in angle of attack to stay in straight and level flight.
True or False?
True.
The effect that a headwind will have on the ROC is…
none, the ROC remains unchanged, however the angle at which the aircraft will climb will be effected.
Angle of ayyack and airspeed are inherently linked, so in a straight and level flight we can assume…..
that as airspeed increases, angle of attack decreases.
