11.13 Landing Gear

Question 1

What are the disadvantages of tail wheel?

Answer 1

Obscured vision
High drag before tail lift
High risk of nose over

Question 2

What is a bogie assembly?

Answer 2

Multiple wheels on a gear rather than single or double.

Question 3

What is a structural fuse pin?

Answer 3

Pins designed to shear in the event of overload.

Question 4

What is the torsion link damper used for?

Answer 4

Counteract wheel shimmy

Question 5

What are the main components of a shortening mechanism?

Answer 5

Adjustable link
Bellcrank lever
Connecting link
Upper and lower link

Question 6

What two classes of shock absorber are there?

Answer 6

Solid- solid spring made of steel or rubber
Oleo pneumatic- fluid spring with gas or oil

Question 7

What is hydraulic dieseling?

Answer 7

Occurs when air mixes with hydraulic cylinder oil. The air forms bubbles in the hydraulic oil.

Question 8

What happens when there is too much oil in the oleo?

Answer 8

The shock strut operates too harshly

Question 9

Why are the brakes applied when the gear is moving up or down?

Answer 9

To avoid the gyroscopic effect.

Question 10

How is the life of the landing gears hydraulic components and prevents leakage?

Answer 10

The selector valves shut off the pressure supply and open the return lines and the brakes are released.

Question 11

What are friction bands or pads installed for?

Answer 11

To stop the wheels from spinning after retraction

Question 12

In small aircraft how are the gear extended when air loads alone are not enough?

Answer 12

They can be cranked by the pilot

Question 13

What does a green light represent in terms of gear position?

Answer 13

Down and Locked

Question 14

What does a red light represent in terms of gear position?

Answer 14

Unlocked or travelling

Question 15

What does no lights represent in terms of gear position?

Answer 15

Up and locked

Question 16

When are prox switches used instead of microswitches?

Answer 16

When there is a high risk of contact corrosion due to dirt and moisture.

Question 17

What two types of prox switch are used on aircraft?

Answer 17

Reed and electronic switch

Question 18

What does a reed switch consist of?

Answer 18

Two spring loaded normally open contacts

Question 19

What melting temp does a red fusible plug have?

Answer 19

155 degrees c

Question 20

What melting temp does a green fusible plug have?

Answer 20

177 degrees c

Question 21

What melting temp does a yellow fusible plug have?

Answer 21

199 degrees c

Question 22

What bearings do aircraft wheels have?

Answer 22

Tapered roller bearings

Question 23

What should brake fires be extinguished with?

Answer 23

Dry powder

Question 24

What aircraft use single disc brakes?

Answer 24

Light Aircraft

Question 25

On a dual disc brake what is between the two discs?

Answer 25

Centre carrier

Question 26

What are the main components of multiple disc brakes?

Answer 26

Piston housing, torque tube and heat pack

Question 27

What is the advantage of carbon heat packs over steel?

Answer 27

40% lighter and can take 50% higher heats Last 20-50% longer

Question 28

What three jobs does a brake piston have?

Answer 28

Apply force Compensate for wear Auto adjust

Question 29

What is the piston clearance?

Answer 29

Distance between piston and spring sleeve

Question 30

What does 1mm of wear equate too?

Answer 30

20-30 landings

Question 31

What does the torque tube do?

Answer 31

Transmits the torque of the stator discs to the piston housings

Question 32

What is the key element in a power brake system?

Answer 32

Brake metering valve

Question 33

What was the first dunlop maxaret system known as?

Answer 33

ABS

Question 34

When is anti-skid inhibited?

Answer 34

Below 25 knots

Question 35

What are type I tyres?

Answer 35

Used on fix gear with a nominal diameter of 27" found on older aircraft

Question 36

What are type III tyres?

Answer 36

Light aircraft with a landing speed of 160 mph.

Question 37

How does the type III tyre number system work?

Answer 37

First- Nominal section width Second- Diameter of rim

Question 38

What is a type VII tyre?

Answer 38

Found on jet aircraft

Question 39

What is a type VIII tyre?

Answer 39

Used on large aircraft, designated by three numbers.

Question 40

What is a radial type VIII designated by?

Answer 40

Letter R

Question 41

What angle is bias ply?

Answer 41

30-60 degrees

Question 42

What angle is radial ply?

Answer 42

Right angle to rotation

Question 43

What 4 parts of a tyre are there?

Answer 43

Bead Carcass plies Tread Sidewall

Question 44

What are the beads?

Answer 44

High tensile strength steel wires embedded in the rubber

Question 45

What are the green or white dots on a tyre?

Answer 45

Awl markings, seepage vents to allow seeping gas to escape

Question 46

What is the red mark on a tyre?

Answer 46

Balance mark

Question 47

What should the red mark line up with?

Answer 47

Align with the heavy spot (normally the valve)

Question 48

What is a rib tread good for?

Answer 48

Paved surfaces

Question 49

What is a diamond tread good for?

Answer 49

Unpaved runways

Question 50

What is an all weather tread?

Answer 50

Rib combined with diamond

Question 51

What is a smooth tyre tread good for?

Answer 51

Older aircraft without brakes

Question 52

What is a chine tyre?

Answer 52

Used on the nose gear of aircraft with fuselage mounted engines.

Question 53

When is rib tread worn?

Answer 53

Less than 2mm depth for more than 25% circumference

Question 54

How many times can a tyre be retreaded?

Answer 54

10 times

Question 55

When does a dry braking flat occur?

Answer 55

When the tyre is locked from rotation while the aircraft is in motion.

Question 56

How does wet braking flat appear?

Answer 56

Almost like its been melted.

Question 57

What must happen to a tyre when it is 80% its inflation?

Answer 57

Be removed along with any other tyre on its axle

Question 58

When does tread chunking occur?

Answer 58

Turning or taxiing quickly

Question 59

What is the general size of chunking allowed?

Answer 59

7cm squared

Question 60

What must happen if a tyre has an open tread joint?

Answer 60

Tyre must be removed

Question 61

When does lateral scoring take place?

Answer 61

When a tyre encounters sideways movement i.e. crosswind landing

Question 62

What is the max size of tread cut allowed?

Answer 62

35mm

Question 63

What must happen if a tyre is exposed to a contaminant up to 12 hours?

Answer 63

Washed off asap, over 12 hours and it must be sent away.

Question 64

What is the storage pressure of tyres?

Answer 64

20-30 psi

Question 65

Aircraft with castor type nose gear steer using what?

Answer 65

Differential braking

Question 66

What is surface effect dampening?

Answer 66

Used in a non-hydraulic shimmy dampener, rubber piston rubs on the cylinder.

Question 67

What do smaller aircraft use instead of cams to align the nose gear on retraction?

Answer 67

Guide pin

Question 68

When the nose gear is steering 70 degrees what can the main gear twist by?

Answer 68

5-8 degrees

Question 69

On large aircraft what does the bogie angle used for?

Answer 69

WOW sensing