Aircraft Landing Gear Systems

Question 1

What is the purpose of a torque link on an oleo strut?

Answer 1

To keep the wheel in alignment and prevent the piston from coming out of the cylinder.

Question 2

A landing gear shock strut should be inflated with what gas(es)?

Answer 2

Nitrogen or dry air.

Question 3

What conditions should a mechanic look for during a regular inspection of the exposed piston section of a landing gear?

Answer 3

Cleanliness, evidence of damage, and proper extension.

Question 4

What prevents air from leaking out between the two halves of a split wheel assembly?

Answer 4

An O-ring.

Question 5

Why are fusible plugs installed on some aircraft wheels?

Answer 5

To release the pressure generated by heat build-up before a tire blows.

Question 6

What safety precaution must be taken when removing a wheel from an axle or when disassembling a wheel?

Answer 6

Verify that the tire is completely deflated before removing a wheel from an axle or before wheel disassembly.

Question 7

What are the visible signs of excessive heating on a wheel bearing?

Answer 7

The bearing surfaces show discoloration.

Question 8

How are the pilot’s nose wheel steering commands transmitted to the steering control unit of a large aircraft?

Answer 8

Steering signals may be transmitted mechanically, electrically, or hydraulically.

Question 9

How is the nose wheel steering mechanism usually actuated on a small aircraft?

Answer 9

By means of a mechanical linkage connected to the rudder pedals.

Question 10

What is the name of the unit that prevents a nose wheel from vibrating or oscillating?

Answer 10

A shimmy damper.

Question 11

What are the most common sources of power used to extend and retract landing gear?

Answer 11

Hydraulic pressure and electric motors.

Question 12

At what times should a gear retraction check be performed?

Answer 12

During annual or other inspections and following a hard landing.

Question 13

What mechanism(s) ensure that a nose wheel is not turned as it retracts into its wheel well?

Answer 13

Internal centering cams in the strut or an external track.

Question 14

Name several types of brake actuating systems.

Answer 14

Independent master cylinders, boosted brakes, and power-controlled brakes.

Question 15

What is the function of an anti-skid system?

Answer 15

Anti-skid systems allow large aircraft to achieve maximum braking effectiveness without allowing wheels to skid or lock.

Question 16

What is the purpose of a debooster?

Answer 16

To reduce hydraulic system high pressure to a lower value for more satisfactory brake action.

Question 17

Describe two methods of bleeding brakes.

Answer 17

A pressure pot can be attached to the bleeder valve and fluid forced back towards the master cylinder and/or reservoir, or the master cylinder can be used for forcing fluid from the reservoir to the brakes.

Question 18

Before a brake system can be inspected for leaks, what action must be accomplished?

Answer 18

Pressure must be applied to the system.

Question 19

What maintenance function has the greatest impact on tire service life?

Answer 19

Ensuring that the tires are properly inflated.

Question 20

What effects does under-inflation have on aircraft tires?

Answer 20

Internal heat damage possibly leading to premature tire failure, and more tread wear on the shoulders than in the center.