6.10

Question 1

What’s 6 advantages of cables ?

Answer 1

1. Strong
2. Light weight
3. Flexible
4. High mechanical efficiency
5. Can be setup without backlash
6. Vibration doesn’t effect cables

Question 2

3 disadvantages of cables ?

Answer 2

1. Tension must be adjusted regularly
2. Prone to wear at points of contact ( pulleys etc )
3. Tension varies with temp changes

Question 3

Whats the construction process of a cable ?

Answer 3

Number of wires braided together forming a strand, number of strands are braided together to form a cable

Question 4

Whats an opposite direction twist called ?

Answer 4

Regular lay - twisting wire and strands in opposite directions reduces the cables tendency to uncoil
( cables either have left or right regular lay )

Question 5

What “lay” is it called if you twist the stands around the central core ?

Answer 5

Lang lay

Question 6

Whats the 4 common types of steel cable used for aircraft ?

Answer 6

1. Non flexible 1x7
2. Non flexible 1x19
3. Flexible 7x7
4. Extra flexible 7x19

Question 7

How many wires and strands are the non flexible 1x7 cable made from ?

Answer 7

1 strand and 7 wires

Question 8

Where are non flexible cables only aloud to be used ?

Answer 8

Straight runs where the cable doesn’t pass over any pulleys.

Question 9

Where are flexible cables used ?

Answer 9

Straight runs, or where large pulleys are being used.

Question 10

Where are extra flexible cables used ?

Answer 10

Used where cables must change direction over small diameter pulleys ( flight controls / trim systems )

Question 11

Whats the 4 cable end fittings ?

Answer 11

1. Terminals
2. Thimbles
3. Bushings
4. Shackles

Question 12

Whats the 4 types of terminal fittings ?

Answer 12

1. Threaded
2. Fork ends
3. Eye ends
4. Single/double shank ball ends

Question 13

What 3 terminals are used to connect a cable to a turnbuckle and bell cranks ?

Answer 13

Threaded
Fork
Eye

Question 14

What are the ball terminals used to attach cables to ?

Answer 14

Quadrants

Question 15

Where are the single shank and double shank ball ends used ?

Answer 15

Single shank - end of cable
Double shank - end of cable or in centre of cable run

Question 16

Why would you use lock clad cables ?

Answer 16

To eliminate sagging and wear in long cables.

Question 17

Whats a lock clad cable made up of ?

Answer 17

Swaged aluminium tubing around steel cable

Question 18

What does the swaged aluminium tubing on lock clad cables do ?

Answer 18

Prevents abrasion of outer wire when pain through bulkheads / other obstructions in the aircraft.

Question 19

Whats a turnbuckle ?

Answer 19

Mechanical screw device which can make minor adjustments I cable length and tension

Question 20

How can the left hand thread side of turn buckle be identified ?

Answer 20

Has a groove at end

Question 21

When screwing turnbuckle onto cable, how many threads should be left exposed at either side of the turn buckle ?

Answer 21

Not more than 3 threads

Question 22

Whats the two ways of locking a turnbuckle ?

Answer 22

1. Lock wire
2. Special clips

Question 23

Why is a cable tension regulator used ?

Answer 23

When the cable tension changes due to expansion and contraction of the aircraft’s structure and cables I flight.

Question 24

Why are pulleys used ?

Answer 24

To guide cables and change their direction.
( pulleys require no further lubrication during use )

Question 25

Why must pulleys have guards ?

Answer 25

To prevent cable jumping out of the grooves when there is lack in the cable

Question 26

When should you use a fair lead ?

Answer 26

When there is a possibility of the cable contacting the aircraft’s structure.

Question 27

Why are control rods used ?

Answer 27

Used in flight control systems to give push pull motion.

Question 28

What can happen to control rods which are fitted with a bearing ?

Answer 28

Can become loose or disconnected due to failure of swaging that retains ball races.

Question 29

What can happen if there is wear where the bell crank connects to the control rod ?

Answer 29

Cause a delay in response to the system it is connecting to.

Question 30

Where is a torque tube used ?

Answer 30

Where there is a twisting motion in a control system.

Question 31

Whats the two most common flexible control systems ?

Answer 31

1. Bowden cables 2. Teleflex control cables

Question 32

What do small light aircraft use Bowden cables for ?

Answer 32

Throttle or fuel mixture control

Question 33

What could cause Bowden cables to fail to function smoothly ?

Answer 33

If water or contaminants enter housing

Question 34

What controls on modern day aircraft do teleflex cables operate ?

Answer 34

1. Engine controls 2. Propeller controls 3. Trimming controls

Question 35

Whats the 3 types of teleflex cables ?

Answer 35

1. DS 23/2 2. DS 380 3. DS 169330

Question 36

Where is a sliding end fitting used ?

Answer 36

Where there is no need to convert the push-pull movement of the cable to rotary.

Question 37

When do you use a quick break unit ?

Answer 37

To facilitate the removal of components without disturbing the control.