Landing Gear Systems

Study Materials

AMT-STRUC, FAA-H-8083-31, AC 43.13-1

Typical Oral Questions

  1. What takes up the shock of the landing impact in an oleo shock strut?

    The metered transfer of oil from one compartment to another inside the shock strut.

  2. What takes up the taxi shocks in an oleo shock strut?

    Compressed air.

  3. How much oil should be put into an oleo shock strut?

    Deflate the strut completely, remove the filler plug and fill the strut with oil to the level of the filler plug.

  4. What is the purpose of the centering cam in a nose-wheel shock strut?

    The centering cam forces the nosewheel straight back with the strut before it is retracted into the nose wheel well.

  5. How does a shimmy damper keep a nosewheel from shimmying?

    It acts as a small hydraulic shock absorber between the piston and the cylinder of the nosewheel shock strut.

  6. What is the purpose of the debooster in a hydraulic power brake system?

    The debooster decreases the pressure and increases the volume of fluid going to the brakes. This gives the pilot better control of the brakes.

  7. What should be done to hydraulic brakes when the pedal has a spongy feel?

    The spongy feel is caused by air in the brake. The brakes should be bled of this air.

  8. What is used in a split wheel to keep air from leaking between the two wheel halves?

    An O-ring seal.

  9. What causes an aircraft tire to wear more on the shoulders than in the center of the tread?

    Operating the tire in an underinflated condition.

  10. What causes an aircraft tire to wear more in the center of the tread than on the shoulders?

    Operating the tire in an overinflated condition.

  11. What should be done to an aircraft tire if the sidewalls are weather checked enough to expose the cord?

    The tire should be scrapped.

  12. Why is it important that some aircraft with retractable landing gear be given a retraction test after new or retreaded tires are installed?

    It is possible in some aircraft that a new or retreaded tire can be different enough in size from the previous tire that it could lock up in the wheel well when the landing gear is retracted.

  13. How is the correct amount of air in an oleo shock strut determined?

    By the amount the strut extends out of the cylinder when the weight of the aircraft is on it.

  14. What should be done with a tire that was on a wheel which was overheated enough to melt the fusible plug in the wheel?

    The tire should be scrapped.

  15. Where can you find the correct inflation pressure for the tires on an aircraft?

    In the aircraft service manual.

  16. What is the purpose of the compensator port in the master cylinder of aircraft brakes?

    The compensator port in the master cylinder opens the brake reservoir to the wheel cylinders when the brakes are off. This prevents pressure from building up in the brake lines and causing the brakes to drag.

  17. What is the purpose of the shuttle valve in the brake system of an aircraft using hydraulic power brakes?

    The shuttle valve is an automatic transfer valve. It allows the brakes to be operated by hydraulic system pressure under all normal conditions, but if this pressure is lost, it allows the brakes to be operated by the emergency backup system.

  18. How does an antiskid brake system keep the wheels of an aircraft from skidding on a wet runway?

    The antiskid system monitors the rate of deceleration of the wheels. If any wheel slows down faster than it should (as it would at the beginning of a skid), the pressure on the brake in that wheel is released until the wheel stops decelerating, then the pressure is reapplied.

  19. Which device in an antiskid brake system would likely cause the brakes to fail to release when a skid developed?

    A malfunctioning antiskid valve.

  20. Where are the skid detectors located in an antiskid brake system?

    In the center of the wheel hub.

  21. What is indicated by a red light in the landing gear position indication portion of the annunciator panel.

    The red light indicates that the landing gear is not in a safe condition for landing.

  22. Where is the landing gear safety switch normally located?

    On one of the landing gear shock struts so the switch is actuated when the weight of the aircraft is on the landing gear.

  23. What information is given to a pilot to indicate that all of the landing gears are down and locked?

    Three green lights are used on most aircraft to indicate that all three landing gears are down and locked.

Typical Practical Projects

  1. Demount a tire from an aircraft wheel, inspect the tire for wear, and the wheel and tire for damage. Reinstall the tire on the wheel.
  2. Check an aircraft brake for the condition of the lining and the discs.
  3. Check the fluid level in an aircraft brake master cylinder.
  4. Bleed an aircraft brake.
  5. Check the fluid level in an aircraft oleo strut. Inflate the strut with the correct amount of air or nitrogen.
  6. Inspect a nosewheel shimmy damper, and service it with fluid if it is needed.
  7. Check the main wheels of an aircraft for the proper amount of camber, and toe-in or toe-out.
  8. Inspect an aircraft tire and explain to the examiner the conditions that could cause a tire to be unairworthy.
  9. Replace the seals in the wheel cylinder of a single-disc brake.
  10. Explain to the examiner the correct way to jack an aircraft so a landing gear retraction check can be performed.
  11. Explain to the examiner the correct way to store aircraft tires.
  12. Explain to the examiner the way a particular retractable landing gear is prevented from retracting when the weight of the aircraft is on it.
  13. Locate and identify for the examiner: the down-limit switches, the up-limit switches, and the landing gear safety switch on an aircraft with retractable landing gear.
  14. Locate and identify for the examiner: the wheel speed sensors, the antiskid valves, and the antiskid control box in an aircraft equipped with an antiskid brake system.
  15. Using a wiring diagram of the landing gear warning system of an aircraft, explain to the examiner the malfunctions that could cause the warning horn to fail to sound when the throttles are retarded and the landing gear is not down and locked.
  16. Demonstrate to the examiner the correct way to check the wheel speed sensors of an antiskid brake system for operation.

[10-2024]