Questions and Answers - Landing Gear | Aircraft Systems

Questions and Answers - Landing Gear

Study Aid Questions

Fill in the Blanks


1. Name the three basic arrangements of landing gear used in aircraft:
_________________   _________________   _________________

2. Parasite drag caused by landing gear can be reduced by the addition of _________________ , or _________________.

3. Most single engine aircraft use a non shock absorbing landing gear made from _________________ , _________________, or _________________ .

4. To keep the shock strut and wheels aligned, most shock struts are equipped with _________________ , and _________________.

5. Nose gear shock struts have a _________________ to keep the gear aligned when the aircraft takes off and the shock strut fully extend.

6. The alignment of a main wheel in the vertical plain is called _________________.

7. The electric/hydraulic landing gear system found in many Cessna and Piper aircraft is called a _________________.

8. The _________________ lowers the landing gear if the main power system fails.

9. The proper functioning of a landing gear system and components can be checked by performing a _________________. This is also known as _________________ the gear.

10. Nose wheel vibration is controlled through the use of a _________________.

11. The inner wheel halve of a wheel used on a high performance aircraft is likely to have one or more _________________.

12. All aircraft axle nuts must be installed and _________________ in accordance with the airframe manufacturer’s maintenance procedures.

13. Overheating of the wheel bearings could be caused by a _________________ and results in a _________________ tint to the metal surface.

14. Brinelling is caused by _________________. It appears as _________________ in the bearing cup raceway.

15. Pushing the _________________ of the right rudder pedal activates the brake on the _________________ main wheel.

16. The _________________ transfers the motions of the pistons to the stack of _________________ and _________________ to slow the rotation of the wheel.

17. The _________________ is the latest iteration of the multiple disc brake.

18. The three brake actuating systems used are __________________________________ and _________________.

19. Power brake systems use the _________________ as the source of power to apply the brakes.

20. The auto brake system is used to stop the wheels automatically after _________________ this prevents the wheels from rotating when retracted in the wheel wells.

21. The anti‐skid system not only detects wheel _________________, it also detects when wheel skid is .

22. Maximum braking efficiency exists when the wheels are decelerating at a maximum rate but are not _________________. 

23. Brake systems with master cylinders may be bled by _________________ or _________________ bleeding methods.

24. A flat spot on a tire is the result of the tire _________________ on the runway surface.

25. Operation on a grooved runway can cause an aircraft tire tread to develop shallow _________________ shaped cuts.


TRUE or FALSE

1. Most aircraft with a tricycle landing gear use differential braking for steering during ground operations. TRUE/FALSE

2. When more than two wheels are attached to a landing gear strut, the attaching mechanism is known as a bogie. TRUE/FALSE

3. Landing gear shock struts are filled with air and synthetic turbine engine oil. TRUE/FALSE

4. During taxi operations the air in the tires and the hydraulic fluid in the shock strut combine to smooth out bumps. TRUE/FALSE

5. To check the fluid level of most shock struts, the strut needs to be deflated and fully compressed. TRUE/FALSE

6. Most smaller aircraft use a powerpack gear retraction system while large aircraft use a hydraulic landing gear retraction system. TRUE/FALSE

7. Sequence valves are often operated mechanically and priority valves control gear component timing via hydraulic volume adjustments. TRUE/FALSE

8. Some aircraft use a mechanical emergency release system that unlocks the uplocks and the gear will free fall, while others use a pneumatic power system to lower the gear when the main system fails. TRUE/FALSE

9. Proximity sensors are used for gear position safety switches on many smaller single engine aircraft. TRUE/FALSE

10. The most common display for the landing gear being up and locked is an illuminated green light. TRUE/FALSE

11. Aircraft equipped with a hydraulic nose wheel steering system utilize the steering cylinders as shimmy dampers. TRUE/FALSE

12. Wheels for modern aircraft use a one piece design which provides superior strength and ease of tire installation. TRUE/FALSE

13. The two pieces of a two piece aircraft wheel are identical and could be used on both the inside as outside of the wheel assembly. TRUE/FALSE

14. Aircraft technicians should be careful when they approach or remove a tire. The high internal pressure of the tire can create a catastrophic failure that could be lethal to the technician. TRUE/FALSE

15. In a fixed disk brake system (Cleveland) the brake caliper and linings adjust their position in relationship to the disc. TRUE/FALSE

16. Dual disc brakes are used on large transport category aircraft that use hydraulic systems to operate the brake systems. TRUE/FALSE

17. In general small light aircraft use independent brake systems. A master cylinder provides the hydraulic pressure. TRUE/FALSE

18. The brake accumulator is an emergency source of power for the brake system. TRUE/FALSE

19. Autobrake systems on large aircraft do not use the anti skid system to control wheel skid. TRUE/FALSE

20. In order to bleed the power brake system of a large transport category aircraft the hydraulic system needs to be pressurized. TRUE/FALSE

21. Type III tires are common general aviation tires, Type V tires are high performance tires found on jet aircraft. TRUE/FALSE

22. Traditional aircraft tires are bias ply tires while modern large aircraft utilize radial tires. TRUE/FALSE

23. When checking tire pressure wait at least 30 minutes after a typical landing to ensure the tire has cooled to ambient temperature. TRUE/FALSE

24. Small pieces of rock or debris can be removed with a probing tool or screwdriver while the tire is on the aircraft and inflated. TRUE/FALSE

25. Under inflation could be evident from excessive wear on the outside of the tire threads. TRUE/FALSE


Knowledge Application Questions

1. What is used to service an air/oil landing gear shock strut?
_____________________________________________________________________

2. What regular inspection should be made of the exposed portion of a landing gear strut?
_____________________________________________________________________

3. What is the purpose of main landing gear torque links and arms?
_____________________________________________________________________

4. What power sources are normally used to retract landing gear systems?
_____________________________________________________________________

5. What type of nosewheel steering is provided on small aircraft?
_____________________________________________________________________

6. What unit prevents nosewheel vibration?
_____________________________________________________________________

7. What is the purpose of power brake debooster cylinders?
_____________________________________________________________________

8. Name the common types of brake systems used on aircraft?
_____________________________________________________________________

9. What must be accomplished before inspecting a wheel brake system for hydraulic leaks?
_____________________________________________________________________

10. What prevents a split wheel from leaking air through the inner and outer mating surfaces, or the wheel assembly?
_____________________________________________________________________

11. What is the most important maintenance action for safe, long, aircraft tire service?
_____________________________________________________________________

12. What are the effects of under inflation on tires?
_____________________________________________________________________

13. When should a landing gear retraction check be accomplished?
_____________________________________________________________________

14. What is the indication of excessive heating of a wheel bearing?
_____________________________________________________________________

15. What is the purpose of an anti‐skid system?
_____________________________________________________________________

16. What is the purpose of a wheel fusible plug?
_____________________________________________________________________

17. What are some methods of bleeding brakes?
_____________________________________________________________________

18. What methods are used for transmitting the brake pedal movements to a steering control unit in large aircraft?
_____________________________________________________________________

19. What prevents a nose landing gear from being retracted with the nosewheel out of the center position?
_____________________________________________________________________

20. What type of material is used for modern brake rotors on transport category aircraft?
_____________________________________________________________________


Multiple Choices Questions

1. What should be checked when a shock strut bottoms during a landing?
a. Air pressure
b. Packing seals for correct installation
c. Fluid level

2. Overinflated aircraft tires may cause damage to the:
a. brake linings
b. wheel hub
c. wheel flange

3. What is the function of a cam incorporated in a nose gear shock strut?
a. Provides an internal shimmy damper
b. Straightens the nosewheel
c. Provides steering of aircraft during ground operation

4. Debooster cylinders are used in brake systems primarily to:
a. reduce brake pressure and maintain static pressure
b. relieve excessive fluid and ensure a positive release
c. reduce the pressure to the brake and increase the volume of fluid flow

5. The purpose of a relief valve in a brake system is to:
a. reduce pressure for brake application
b. prevent the tire from skidding
c. compensate for thermal expansion

6. A high speed aircraft tire with a sound cord body and bead may be recapped:
a. a maximum of three times
b. only by the tire manufacturer
c. an indefinite number of times

7. The fusible plugs installed in some aircraft wheels will:
a. indicate tire tread separation
b. prevent over inflation
c. melt at a specified elevated temperature

8. Instructions concerning the type of fluid and amount of air pressure to be put in a shock strut are found:
a. on the airplane data plate
b. in the aircraft operations limitations
c. in the aircraft manufacturer's service manual

9. The primary purpose for balancing aircraft wheel assemblies is to:
a. prevent heavy spots and reduce vibration
b. distribute the aircraft weight properly
c. reduce excessive wear and turbulence

10. The pressure source for power brakes is:
a. the main hydraulic system
b. the power brake reservoir
c. a master cylinder

11 What is the purpose of the torque links attached to the cylinder and piston of a landing gear oleo strut?
a. Limit compression stroke
b. Hold the strut in place
c. Maintain correct wheel alignment

12 When an air/oil type of landing gear shock strut is used, the initial shock of landing is cushioned by:
a. compression of the air charge
b. the fluid being forced through a metered opening
c. compression of the fluid

13 The purpose of a sequence valve in a hydraulic retractable landing gear system is to:
a. prevent heavy landing gear from falling too rapidly upon extension
b. provide a means of disconnecting the normal source of hydraulic power and connecting the emergency source of power
c. ensure operation of the landing gear and gear doors in the proper order

14. Which statement is true with respect to an aircraft equipped with hydraulically operated multiple disk type brake assemblies?
a. There are no minimum or maximum disk clearance checks required due to the use of self compensating cylinder assemblies
b. Do not set parking brake when brakes are hot
c. No parking brake provisions are possible for this type of brake assembly

15. Nose gear centering cams are used in many retractable landing gear systems. The primary purpose of the centering device is to:
a. align the nosewheel prior to touchdown
b. engage the nosewheel steering
c. center the nosewheel before it enters the wheel well

16. How long should you wait after a flight before checking tire pressure?
a. At least 3 hours
b. At least 2 hours
c. At least 30 minutes

17. An electric motor used to raise and lower a landing gear would most likely be a
a. shunt field series wound motor
b. split field shunt wound motor
c. split field series wound motor

18. A landing gear position and warning system will provide a warning in the cockpit when the throttle is
a. retarded and gear is not down and locked
b. advanced and gear is down and locked
c. retarded and gear is down and locked

19. Excessive wear in the center of the tread of an aircraft tire is an indication of:
a. incorrect camber
b. excessive toe out
c. over inflation

20. On most aircraft, the oil level of an air and oil shock strut is checked by:
a. removing the oil filler plug and inserting a gauge
b. measuring the length of the strut extension with a certain air pressure in the strut
c. releasing the air and seeing that the oil is to the level of the filler plug

21. How can it be determined that all air has been purged from a master cylinder brake system?
a. By operating a hydraulic unit and watching the system pressure gauge for smooth, full scale deflection
b. By noting whether the brake is firm or spongy
c. By noting the amount of fluid return to the master cylinder upon brake release

22. The best safeguards against heat buildup in aircraft tires are:
a. proper tire inflation, minimum braking, and ground rolls into the wind
b. short ground rolls, slow taxi speeds, minimum braking, and proper tire inflation
c. minimum braking, proper tire inflation, and long ground rolls

23 In brake service work, the term 'bleeding brakes' is the process of:
a. withdrawing air only from the system
b. withdrawing fluid from the system for the purpose of removing air that has entered the system
c. replacing small amounts of fluid in reservoir

24 Aircraft brakes requiring a large volume of fluid to operate the brakes generally:
a. use independent master cylinder systems
b. do not use brake system accumulators
c. use power brake control valves

25. To prevent a very rapid extension of an oleo shock strut after initial compression resulting from landing impact:
a. various types of valves or orifices are used which restrict the reverse fluid flow
b. the metering pin gradually reduces the size of the orifice as the shock strut extends
c. the air is forced through a restricted orifice in the reverse direction

26. The metering pins in oleo shock struts serve to:
a. lock the struts in the DOWN position
b. retard the flow of oil as the struts are compressed
c. meter the proper amount of air in the struts

27. After performing maintenance on an aircraft's landing gear system which may have affected the system's operation, it is usually necessary to:
a. conduct a flight test
b. re‐inspect the area after the first flight
c. make an operational check with the aircraft on jacks

28. Why do tire and wheel manufacturers often recommend that the tires on split rim wheels be deflated before removing the wheel from the axle?
a. to relieve the strain on the wheel retaining nut and axle threads
b. as a safety precaution in case the bolts that hold the wheel halves together have been damaged or weakened
c. to remove the static load imposed upon the wheel bearings by the inflated tire

29. Exposure to and/or storage near which of the following is considered harmful to aircraft tires?
1. Low humidity   2. Fuel                                3. Oil                          4. Ozone
5. Helium             6. Electrical equipment       7. Hydraulic fluid       8. Solvents

a. 2, 3, 4, 5, 6, 7, 8
b. 1, 2, 3, 5, 7, 8
c. 2, 3, 4, 6, 7, 8

30. On all aircraft equipped with retractable landing gear, some means must be provided to:
a. retract and extend the landing gear if the normal operating mechanism fails
b. extend the landing gear if the normal operating mechanism fails
c. prevent the throttle from being reduced below a safe power setting while the landing gear is retracted



SUPPORTING LESSONS
Aircraft Landing Gear System
Landing Gear Types
Landing Gear Configuration
Shock Strut
Landing Gear Alignment
Landing Gear Support
Landing Gear Retraction
Landing Gear Emergency Extension Systems
Landing Gear Safety Devices
Landing Gear System Maintenance
Nose Wheel Steering Systems
Aircraft Wheels
Aircraft Brakes