Mod 4-5 Quiz

Question 1

what is induced flow

Answer 1

the direction of airflow through the rotor blades.

Question 2

what is translational lift? what effect will it have on the aircraft?

Answer 2

transitional state that a helicopter experiences moving from a hover to directional flight

will cause buffeting of the airframe

Question 3

when a helicopter is in a hover, what is the difference between being in ground effect (IGE) and out of ground effect (OGE)

Answer 3

IGE - the helicopter is hovering one half to one full rotor disc diameter from the ground causing the downwash from the rotor blades to create a cushion of air that allows the helicopter to use less HP while Hovering

OGE - the helicopter is one half to one full rotor disc diameter away from the ground so downwash has no effect on the required power for a hover.

Question 4

True or False, a helicopter can hover at a higher altitude while in ground effect that it can out of ground effect

Answer 4

true

Question 5

what is dissymmetry of lift? what is its effects of the aircraft?

Answer 5

a difference in blade speeds while the helicopter is in directional travel

can cause heli to flip

Question 6

what are two solutions for dissymmetry of lift

Answer 6

Flapping hinge and Differential cyclic

Question 7

what is differential cyclic

Answer 7

a difference in blade pitch dependent on the position of the blade

retreating blades will have higher pitch while advancing blades have lower pitch

Question 8

what is the law of conservation of angular momentum?

Answer 8

the theory that when the centre of mass of a rotating object moves towards the centre of rotation, the object will accelerate

Question 9

what are two solutions to the conservation of angular momentum problem

Answer 9

lead lag hinge

underslung mounting

Question 10

what is a retreating blade stall

Answer 10

it is when the rotational velocity and the velocity of flight are equal causing that blade to stall while the other blades continue making lift

Question 11

what is vortex ring state

Answer 11

decent through the rotor downwash causing the helicopter to eat its own wake and stall the blades

Question 12

what is mast bumping

Answer 12

the action of the rotor head striking the mast as a result of low G pushovers

Question 13

what is a major consequence of mast bumping

Answer 13

separation of the rotor head from the airframe

Question 14

what movement do anti torque pedals control? how do they control it

Answer 14

yaw

changing the pitch of the tail rotor blades

Question 15

what is the collective? where is it located

Answer 15

the control used for throttle adjustments

located to the left hand side of the pilot seat

Question 16

what additional controls can be located on the collective

Answer 16

landing lights
start switch
idle release

Question 17

what is the cyclic? what movement does it controll

Answer 17

the cyclic is the main joystick located between the pilots legs. it is used to control the pitch and roll movements of the aircraft

Question 18

what additional controls can be located on the cyclic

Answer 18

push - to - talk
cargo hook release
trim

Question 19

what does a mixing unit do

Answer 19

converts separate cyclic and collective inputs into a common set of outputs

Question 20

what is the difference between a scissor link and a drive link

Answer 20

scissor link is connected to the stationary swashplate while the drive link is connected to the rotating swashplate and the mast and provides rotational force

Question 21

what effect does centrifugal twisting force have on a rotor blade

Answer 21

wants to return the blade to low / fine pitch angle

Question 22

what is used to counteract centrifugal twisting force

Answer 22

collective spring or counterweights

Question 23

what is flight control friction

Answer 23

it adds extra friction to a flight control to hold it in a set position and take the load away from the pilot

Question 24

what is aerodynamic twisting force

Answer 24

it wants to move the rotor blades to a higher pitch angle

Question 25

what is artificial feel used for

Answer 25

it provides haptic feeback to the pilot to allow them greater control of the aircraft