undercarriage

Question 1

what two configurations of undercarriage is there?

Answer 1

tricycle
tailwheel

Question 2

what is undercarriage used for?

Answer 2

to cushion landings

Question 3

what types of (fixed) undercarriage are there?

Answer 3

spring steel undercarriage
oleo undercarriage

Question 4

how does oleo undercarriage work?

Answer 4

combined gas and oil act as a dampening shock absorber
gas = shock absorber
oil = damping action

Question 5

what gas is used in oleo undercarriage?

Answer 5

nitrogen

Question 6

what does torque link do?

Answer 6

keeps the wheel pointing in the right direction whilst allowing up and down movement

Question 7

what does the amount of visible oleo extension show?

Answer 7

shows the amount of oil and gas present in the system

Question 8

when and what happens when nose wheel oleo reaches full extension?

Answer 8

happens in the air
nose wheel self-centres and disengages from rudder pedals

Question 9

how does nose wheel steering behave on a crosswind takeoff?

Answer 9

as nose oleo reaches full extension, positive nose wheel steering will be lost (so different amount of rudder needed to keep straight)

Question 10

what is nose wheel shimmy?

Answer 10

when nose wheel wobbles side to side

Question 11

what is done to reduce nose wheel shimmy?

Answer 11

shimmy damper - stops it from wobbling side to side but still allows for slight movement

Question 12

what is nose wheel shimmy caused by?

Answer 12

failure of torque link

Question 13

what other conditions can cause nose wheel shimmy?

Answer 13

incorrect tyre pressure
tyre is worn unevenly
shimmy damper fluid level low
nose wheel bearings worn

Question 14

how do you cope with nose wheel shimmy?

Answer 14

use full up elevator, ease off braking

Question 15

what happens if tyre pressure is too hard?

Answer 15

bounce on landing

Question 16

what happens if tyre pressure is too soft?

Answer 16

tyre bursts or deflates on landing

Question 17

what happens if creep marks slip around the rim?

Answer 17

stress on inner tube and valve stem

Question 18

how is tyre wear affected if tyre pressure is too high?

Answer 18

tyre wears in the centre = higher aquaplaning speed

Question 19

how is tyre wear affected if tyre pressure is too low?

Answer 19

tyre wears at shoulders = lower aquaplaning speed

Question 20

what are the components of the drum (on the brakes)?

Answer 20

rotating drum has arc-shaped shoes inside, they press against inner drum surface

Question 21

what is drum fading?

Answer 21

when drum expands away from shoes as it heats up due to braking

Question 22

where is the disc on the brakes?

Answer 22

gripped between two friction pads

Question 23

what are the operating methods of the brakes?

Answer 23

hydraulic
compressed air
cable/rod

Question 24

how does the hydraulic method of braking work?

Answer 24

non-compressing oil based fuel is used to force shoes/pads against drum/disc

Question 25

how does the compressed air method of braking work?

Answer 25

expands internal balloons that press shoes against drum

Question 26

how does the cable/rod method of braking work?

Answer 26

forces shoes/pads against drum/disc mechanically

Question 27

parking brakes can be mechanical OR hydraulic shut off valve. true or false?

Answer 27

true

Question 28

what are strakes used for? what are they?

Answer 28

to assist in spin recovery - they are fillets on parts of the fuselage

Question 29

what are static wicks used for?

Answer 29

to dissipate static electricity that can build up

Question 30

where are airborne static wicks found?

Answer 30

on trailing edge of control surfaces

Question 31

where are ground static wicks found?

Answer 31

attached to wheel axles with trailing wire that contacts the ground

Question 32

what is control surface bonding?

Answer 32

to ensure whole aircraft is electrically bonded

Question 33

how does control surface bonding work?

Answer 33

flexible metallic connections prevent static build up on controls surfaces