Flight Controls (S1)

Question 1

What are the requirements of the rotor head

Answer 1

Provide attachment point for rotor blades
Transmit drive from engine to the rotor blades
Allow blade freedom of movement
Allow a control interface to change the pitch
Support the blades

Question 2

What are the main types of rotor head

Answer 2

Fully articulated
Semi rigid
Rigid

Question 3

What additions can be present on a rotor head

Answer 3

Lifting eye
Flapping restrainer
Droop restrainer

Question 4

What is a drag damper used for

Answer 4

To reduce the rate of dragging and absorb shock loads

Question 5

What type of drag dampers are there

Answer 5

Elastomeric
Hydraulic

Question 6

What is the purpose of the tie bar

Answer 6

To absorb centrifugal loads generated by rotating blades

Question 7

What 3 attachments does the MRBS have

Answer 7

Pitch bearings
Tie bar
Damper support

Question 8

What does the tie bar do and how does it work

Answer 8

Connects the sleeve to the rotor head, is made using miles of wound wire around 2 bushes, wound at an angle to offset the aerodynamic affects on pitch

Question 9

What is the purpose of the rotor blades

Answer 9

Produce a force greater than the weight of the aircraft to provide thrust

Question 10

How can blade lift be evenly distributed

Answer 10

Wash-out
Tapered blades

Question 11

What can be used to balance blades

Answer 11

Weights

Question 12

What is used to aid the instalment of blade pins

Answer 12

Bullet adaptors that help get past any misalignments without damaging the pin

Question 13

What is a bonding lead and its purpose

Answer 13

A cable completing the electrical path from the rotor head to the blade to reduce damage to aircraft during lightning strikes, to prevent static buildup and reduce electric shock hazard

Question 14

What are trim tabs

Answer 14

Small device fitted to the trailing edge to balance the blade aerodynamically. Done by manufacturers

Question 15

What does a static wick do

Answer 15

Discharges static electricity

Question 16

What is the lift load path

Answer 16

MRB
Rotor head
Rotor mast
Gearbox casting
Gearbox supports
Airframe mountings

Question 17

What methods ore there of negating vibration

Answer 17

Mass/spring main rotor head vibration absorber (MRHVA)
Bifilar vibration absorber
Active vibration cancellation

Question 18

What are the 3 types of tail rotor

Answer 18

Free (Lynx, Apache)
Shrouded (Gazelle)
NOTAR

Question 19

What are the disadvantages of shrouded tail rotors

Answer 19

Increase in weight
Increase in power requirement
Increase in drag
Higher costs

Question 20

What are the 5 main parts of a tail rotor blade

Answer 20

Spar
Root end
Skin
Erosion shield
Blade tip

Question 21

What should be checked for during rotor blade maintenance

Answer 21

Dents, cracks, distortions
Attachments
Bearing wear
Damage to tips and tabs
Balancing

Question 22

What 2 systems are used to alter MRB pitch

Answer 22

Swash plate system
Spider system

Question 23

What is geometric lock

Answer 23

Where cables and rods aren’t correctly adjusted and can cause controls to become locked after they get caught on each other

Question 24

What 2 measures are there to make sure control rods are correctly tightened

Answer 24

Witness hole
Witness line

Question 25

What is used to change rod inputs to cables or vice versa

Answer 25

Quadrant

Question 26

What are control stops

Answer 26

Adjustable or fixed stops that restrict the movement of the control inputs, to prevent geometric locking and prevent dangerous inputs

Question 27

What type of cable is used on cable control systems

Answer 27

Preformed cable Kink resistant and will not unravel

Question 28

What are turnbuckles

Answer 28

Used to join and adjust the length of wire control systems.

Question 29

How are turnbuckles secured

Answer 29

Wire locking Provided locking clips

Question 30

What types or turnbuckles are there

Answer 30

Tension Barrel

Question 31

What is a swaged end

Answer 31

Clamping and forming the end of a cable to secure it

Question 32

What are fairleads

Answer 32

Restrainers along a cable system to limit the amount of movement of the cable during vibrations

Question 33

How can left hand threads be identified

Answer 33

Notches in the nut Grooves

Question 34

What is an interlink assembly

Answer 34

Linked controls to deal with collective, cyclic or yaw inputs that keep the aircraft level

Question 35

How can constant rotor speed be maintained

Answer 35

Automatic fuel supply changes to the engine made by a computer to change the output from the engine

Question 36

What is rigging

Answer 36

The truing and checking the system to ensure the flying controls operate correctly

Question 37

What are rigging pins

Answer 37

Pins used to hold control systems into a predefined position for tests to be carried out (neutral position)

Question 38

What are the 2 parts of an independent inspection

Answer 38

Correct assembly check Functional systems check

Question 39

When is rigging carried out

Answer 39

At specific intervals laid down by AMM After disturbing any part of the control system

Question 40

What are the design requirements of rotor blades

Answer 40

Have good lift:drag ratio Maximum lift required Minimise pitching moments

Question 41

What are the 3 areas of a blade

Answer 41

Root Centre Tip

Question 42

What are doubler plates

Answer 42

Plates at the blade root, increase the strength of the blade in critical area

Question 43

How can rotor blades be identified

Answer 43

Colour coding