The Landing Gear

Question 1

Advantages of a tricycle gear

Answer 1

Better directional stability (CG further forward)
Less likely to nose over
Less drag improves takeoff performance.

Question 2

Most common types of fixed landing gear

Answer 2

Spring Steel Leg / Cantilever

Rubber cord or bungee

Oleo Pneumatic Struts

Question 3

Purpose of torque/torsion link

Answer 3

Stops plunger/sliding tube from rotating inside leg/body

Question 4

Bogie Definition

Answer 4

Have at least for wheels per landing gear leg

Question 5

Main disadvantage of bogie

Answer 5

When turning, crabbing will occur due to large footprint.

Question 6

What acts as a damper (whole system)

Answer 6

The oil and nitrogen

Question 7

What acts as a spring?

Answer 7

The gas acts as a spring to absorb the loads.

Question 8

What acts as a damper?

Answer 8

The oil acts to dampen the spring action

Question 9

Most likely cause of the fescalised portion of the leg being too small is:

Answer 9

Insufficient N2 pressure

Question 10

Consequence of insufficient nitrogen gas in oleo strut?

Answer 10

Bottoming-out on landing

Question 11

Ramifications of insufficient oil

Answer 11

Gear rebound is not properly damped

Question 12

Purpose of mechanical lock?

Answer 12

Prevents creep.

Question 13

Break Bars

Answer 13

Torque limiting devices that limits force through brakes, then through the wheels.

Question 14

Nose Wheel Requirements

Answer 14

Free Castoring, to allow differential braking

Automatic self centering to ensure nosewheel is centered prior to retraction.

Shimmy Protection

Question 15

Which additional load may nosewheel steering cause on the landing gear?

Answer 15

Towing - Shear

Question 16

Define Castoring

Answer 16

The ability of the nosewheel to move either side of the neutral position.

Question 17

Ground Locks

Answer 17

Must be removed before flight.

Question 18

What prevents the inadvertent retraction of the landing gear on the ground?

Answer 18

A solenoid operated LATCH pin

Question 19

Emergency Gear Extension

Answer 19

Via Gravity, however doors will be too big to close. Therefore the protruding material is frangible, and will be replaced.

Question 20

Amber Lights - Indication

Answer 20

Amber lights are for DOOR INDICATION.

Question 21

Scenario - no landing gear main lights, however 1 is amber. What is a possible scenario?

Answer 21

Undercarriage is up and locked. Landing gear doors are party open/not fully closed.

Question 22

Continuous L/G Horn

Answer 22

Will sound if in landing configuration, throttles are set to less than 33%, will continue until L/G is down and locked.

Question 23

Red Landing Gear Indication

Answer 23

Gear is unlocked

Question 24

VLE

Answer 24

Maximum Speed with Landing Gear Extended

Question 25

VLO

Answer 25

Maximum Landing Gear Operating Speed - Undercarriage doors limiting factor, slowest of the landing gear speeds.

Question 26

What does a tiller operate?

Answer 26

Small electric / hydraulic motor connected to nosewheel strut.

Question 27

Nosewheel Shimmy

Answer 27

Rapid, sinusoidal oscillation of the nosewheel, divergent in nature.

Question 28

Caushes of Shimmy

Answer 28

Uneven tyre pressures Uneven worn tyres Unbalanced wheels Worn shimmy damper Worn torque link

Question 29

Reduction of shimmy

Answer 29

Hydraulic jack across steering jack piston Hydraulic damper Double nosewheels

Question 30

Maarstrand Tyres

Answer 30

Twin contact tyres

Question 31

What is the purpose of a loose/detachable flange

Answer 31

Designed to facilitate tyre replacement

Question 32

Define Tyre Creep

Answer 32

Tendency of the tyre to rotate around the circumference of the wheel.

Question 33

Purpose of Fusible Plugs

Answer 33

Prevent the tyre against explosion due to excessive temperature.

Question 34

How many Fusible Plugs are there, and where are they fitted?

Answer 34

One or more, on inner half of the wheel