NAA - Landing Gear Systems

What is the minimum amount of time to wait for tires to cool before checking tire pressure?

3 Hours

What permits fluid to flow towards or away from a reservoir in an independent brake system master cylinder?

Compensating valve

The red dot on a tire indicates?

Light spot.

A pilot write-up states that the left brake is dragging excessively, a quick check of records indicates no recent brake work, what is probably wrong?

Master cylinder compensating part has FOD in it.

What device in a hydraulic system with a constant-delivery pump allows circulation of the fluid when no demands are on the system?

Pressure regulator.

Why are Aircraft wheel assemblies balanced?

Prevents heavy spots and reduces vibrations.

The best safeguards against heat buildup in aircraft tires is?

Proper inflation, minute braking short ground rolls, slow taxi speeds.

When installing a chevron type seal, the open side of the seal should?

face the fluid.

How many times can a wheel be recapped with a sound carcass?

indefinitely

Debooster cylinders are used in brake systems primarily to

reduce the pressure to the brake and increase the volume of fluid flow.

Explain the reason brake are bled?

to remove air.

Aircraft brakes requiring a large volume of fluid to operate the brakes generally

use power brake control valves.

The hydraulic packing seals used in a landing gear shock strut are

used only with a specific type of fluid.

How is it determined in a master cylinder brake system that all of the air has been purged from the system?

By depressing the brake and noting that the brake is firm and not spongy.

If it is determined that spongy brake action is not caused by air in the brake system, what is the next most likely cause?

Deteriorated flexible hoses.

Generally speaking, how is the oil level of an oleo shock strut checked?

Discharge the air and check the level thru the filler plug with the strut fully compressed.

What is an effect of a restricted compensator port of a master cylinder?

Dragging brakes.

What should be checked when a shock strut bottoms during a landing?

Fluid level.

What is the purpose of the torque links attached to the cylinder and piston of a landing gear oleo strut?

Maintain correct wheel alignment.

What restricts or retards the flow of oil in a oleo shock strut?

Metering Pin

How often should Aircraft tire pressure be checked?

Minimum once a week.

A master cylinder with a single disc system that has excessive brake pedal travel indicates what?

Worn lining.

If a shock strut bottoms after it has been properly serviced, the

strut should be removed, disassembled, and inspected.

Over inflated tires causes wear to what area of the wheel assembly?

the center area of the tire tread.

When an air/oil type of landing gear shock strut is used, the initial shock of landing is cushioned by

the fluid being forced through a metered opening.

What is the distinguishing characteristic of a high pressure Schrader valve core when compared to a tire valve core?

"H" stamped on it.

Which statement is true with respect to an aircraft equipped with hydraulically operated multiple-disk type brake assemblies?

Do not set parking brake when brakes are hot.

What condition would most likely cause excessive fluctuation of the pressure gauge when the hydraulic pump is operating?

Inadequate supply of fluid.

When will a continuous horn provide a warning in the cockpit?

When the throttle is retarded and gear is not down and locked.

Aircraft tire pressure should be checked

at least once a week or more often.

If a brake debooster is used in a hydraulic brake system, its position in the system will be

between the brake control valve and the brake actuating cylinder.

In shock struts, chevron seals are used to

prevent oil from escaping.

The pressure source for power brakes is

the main hydraulic system.

Internal leakage in a brake master cylinder unit can cause

the pedal to slowly creep down while pedal pressure is applied.

Excessive wear in the shoulder area of a tire is an indication of

under inflation.

Excessive wear in the shoulder area of an aircraft tire is an indication of

underinflation.

A special bolt in a landing gear attachment requires a torque value of 440 inch-pounds. How many foot-pounds are required?

36.6.

How many inch pounds is a foot pound?

12 in/lbs

The trunnion nut on an aircraft landing gear requires a torque of 320 inch-pounds. To reach the nut, a 2-inch straight adapter must be used on an 18-inch torque wrench. How many foot-pounds will be indicated on the torque wrench when the required torque of the nut is reached?

24

How long is a mechanic suppose to wait before checking tire pressure on an Aircraft that just pulled into the gate?

3 hours

How long should you wait after a flight before checking tire pressure?

3 hours

What type of valve is used in the brake actuating line to isolate the emergency brake system from the normal power brake control valve system?

A shuttle valve.

On an air valve core stem, what indicates high-pressure type?

An embossed letter 'H.'

Aside from an external leak in the line, what will cause parking brakes to continually bleed off pressure?

An internal leak in the master cylinder.

What action, if any, should be taken when there is a difference of more than 5 pounds of air pressure in tires mounted as duals?

Correct the discrepancy and enter in the aircraft records.

Many brake types can be adapted to operate mechanically or hydraulically. Which type is not adaptable to mechanical operation?

Expander-tube type.

What purpose does the various types of orifices and valves that are located inside of an oleo strut serve after initial compression at landing?

Fluid is forced thru these restrictions in a reverse direction to prevent rapid extension of the strut.

Why did we inflate/deflate, then re-inflate our tube tires when performing our landing gear wheel remove & replace?

Following procedure to ensure correct tube position.

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!

Fuel Oil Ozone Electrical Equipment Hydraulic Fluid Solvents

What does a yellow dot on a tube indicate?

Heavy spot.

Power boost brake systems are sued on Aircraft that have

High landing speeds.

What function does a lockout debooster generally have?

It allows full debooster piston travel without fluid from high pressure side entering the low pressure chamber.

What is the purpose of scissor or torque links on a landing gear?

It keeps the wheels pointed in the right direction.

Is it a good idea to set the parking brakes on a large aircraft with multi disc type brake assemblies when they are Hot?

No

What action should be taken whenever maintenance is performed that will affect the landing gear system performance

The aircraft should be placed on jacks and a retraction test should be performed

What would be the effect if the piston return spring broke in a brake master cylinder?

The brakes would drag.

What is one effect a restricted compensator port of a master cylinder will have on a brake system?

The restriction will cause slow release of the brakes.

Why do most aircraft tire manufacturers recommend that the tubes in newly installed tires be first inflated, fully deflated, and then reinflated to the correct pressure?

To allow the tube to position itself correctly inside the tire.

When working with high pressure, high performance tires, why is it recommended to deflate the tires when removing wheels from the axle?

To ensure safety in case of a defective wheel or broken tie bolts.

What is the primary reason debooster cylinders are used in brake systems?

To reduce the pressure to the brake and increase the volume of fluid flow.

Is a log book entry required for a tire pressure reading five PSI low?

YES

An O-ring intended for use in a hydraulic system using MIL-H-5606 (mineral base) fluid will be marked with

a blue stripe or dot.

What limits the extension stroke of an inner cylinder piston of an oleo type shock strut?

a sleeve, spacer or a pumper ring.

A fully-charged hydraulic accumulator provides

a source for additional hydraulic power when heavy demands are placed on the system.

The repair for an out of tolerance toe out condition of a main landing gear wheel that is determined not to be the result of a damaged component is?

adjusting the torque links with shims.

A pilot reports the right brake on an aircraft is spongy when the brake pedal is depressed in a normal manner. The probable cause is

air in the brake hydraulic system

Lockout deboosters are primarily pressure reducing valves that

allow full debooster piston travel without fluid from the high pressure side entering the low pressure chamber.

The repair for an out-of-tolerance toe-in condition of main landing gear wheels determined not to be the result of bent or twisted components consists of

inserting, removing, or changing the location of washers or spacers at the center pivotal point of the scissor torque links.

A flexible hydraulic hose identified as MIL-H-8788 will have a strip running the length of the hose. This stripe is

installed without excessive twisting.

A pilot reports that his parking brake slowly releases, you find no visible external leak, what is mostly likely wrong?

internal leak in master cylinder.

Inbound flight crew radio's in that the nose gear bottomed on landing, but is now functioning OK. What is most likely wrong with that shock strut?

it has low fluid level.

A pilot reports that when braking, he has excessive pedal travel. The most likely cause is?

it has worn linings.

A pilot reports that the brake pedals have excessive travel. A probable cause is

lack of fluid in the brake system & worn brake pads.

What is the most likely result of internal leaking of a brake master cylinder?

may result in a pedal that feels mushy, spongy, or slowly sinks to the floor when depressed.

The fusible plugs installed in some aircraft wheels will

melt at a specified elevated temperature.

What is the purpose of a fusible plug on Aircraft wheels?

melt at specified temperature.

The primary purpose for balancing aircraft wheel assemblies is to

prevent heavy spots and reduce vibration.

The removal, installation, and repair of landing gear tires by the holder of a private pilot certificate on an aircraft owned or operated is considered to be

preventive maintenance.

Extension of an oleo shock strut is measured to determine the

proper operating position of the strut.

When servicing an empty shock strut with fluid, the strut should be completely compressed and extended several times to ensure

proper packing ring seating and removal of air bubbles.

What are firm brakes an indication of?

properly bled brakes.

The best safeguards against heat buildup in aircraft tires are

short ground rolls, slow taxi speeds, minimum braking, and proper tire inflation.

What type of valve is used in the brake actuating line to isolate the emergency brake system from the normal brake system on the Lear Jet?

shuttle valve.

A stripe or mark applied to a wheel rim and extending onto the sidewall of a tube-type tire is a

slippage mark.

An electric motor used to raise and lower a landing gear would most likely be a

split field series-wound motor.

A brake debooster valve is installed in systems where the high pressure of the hydraulic system (3000 psi) is used to operate brakes

that are designed to work with lower pressure.

What effect would the piston return spring in a master cylinder that is broken have?

the brakes would drag.

When installing a chevron-type seal in an aircraft hydraulic cylinder, the open side of the seal should face

the direction of fluid pressure.

Name six hazards that can damage a tire if exposed to in storage.

Fuel Oil Ozone Electrical Equipment Solvents Hydraulic Fluid

What system supplies the power brakes with pressure?

Main hydraulic system.

Is a tire change required for a tire pressure reading five PSI lower than the other tire on a dual mounted axie?

NO

If maintenance was performed on an aircraft landing gear that might affect it's operation, what is required?

Ops check & gear swing.

What purpose does a stipe or mark applied to a wheel that extends onto the tire serve?

Slippage mark.

Over inflated tires can cause damage to

The wheel flange.

If the extended longitudinal axis of a main landing gear intersects forward of an aircraft, this condition is known as

Toed in.

A high-speed aircraft tire with a sound cord body and bead may be recapped

an indefinite number of times.

Chines are used on some aircraft nose wheel tires to help

deflect water away from the fuselage.

A sleeve, spacer, or bumper ring is incorporated in a landing gear oleo shock strut to

limit the extension stroke.

If an aircraft shock strut (air/oil type) bottoms upon initial landing contact, but functions correctly during taxi, the most probable cause is

low fluid.

The light spot of a tire should line up with what part of a tubeless rim?

the valve stem.

The red dot on a tire should line up with what on a tubeless rim?

the valve stem.

A filter incorporating specially treated cellulose paper is identified as a

micronic filter.

What is a distinguishing characteristic of expander type brakes?

not adaptable to a mechanical operation.

Excessive wear in the center of the tread of an aircraft tire is an indication of

overinflation.

Debooster valves are used in brake systems primarily to

reduce the pressure and release the brakes rapidly. Also increase fluid flow free

On most aircraft, the oil level of an air and oil shock strut is checked by

releasing the air and seeing that the oil is to the level of the filler plug.

The purpose of an orifice check valve is to

restrict flow in one direction and allow free flow in the other.

A metering pin in oleo shock struts serve to

retard the flow of fluid.

The metering pins in oleo shock struts serve to

retard the flow of oil as the struts are compressed.

The correct inflation pressure for an aircraft tire can be obtained from

the aircraft service manual.

What ensures that the landing gear doors in a hydraulic system operate in the proper order?

the sequence valve.

What can cause spongy brake besides air in the system?

bad hoses.

The purpose of a relief valve in a brake system is to

compensate for thermal expansion.

Power boost brake systems are used on aircraft that have

high landing speeds.

What is the function of a cam incorporated in a nose gear shock strut?

Straightens the nosewheel.

The braking action of a Cleveland disk brake is accomplished by compressing a rotating brake disk between two opposite brake linings. How is equal pressure on both sides of the rotating disk assured?

By allowing the caliper to float to automatically equalize as pressure is applied to the rotor.

What is the purpose of a compensating port or valve in a brake master cylinder of an independent brake system?

Permits the fluid to flow toward or away from the reservoir as temperature changes.

A close inspection of a fusible plug reveals the core has experienced some deformation. What is the appropriate maintenance procedure?

Replace all the fusible plugs.

When checking a brake pin wear indicator, what is a good maintenance practice to follow?

Set your parking brakes to ON.

Nose gear centering cams are used in many retractable landing gear systems. The primary purpose of the centering device is to

center the nosewheel before it enters the wheel well.

When servicing an air/oil shock strut with MIL-5606 the strut should be

depressurize & collapsed and fluid added at the filler opening.

A brake debooster valve is installed in systems where the high pressure of the hydraulic system is used to operate brakes that are

designed to work with lower pressure.

The purpose of a sequence valve in a hydraulic retractable landing gear system is to

ensure operation of the landing gear and gear doors in the proper order.

On all aircraft equipped with retractable landing gear, some means must be provided to

extend the landing gear if the normal operating mechanism fails.

When bleeding aircraft brakes, one of the indications that the air has been purged from the system is

firm brake pedals.

Why do tire manufactures generally suggest deflating tires on a split rim before removing them from the axle?

for safety precaution.

The left brake is dragging excessively on an airplane on which no recent brake service work has been performed. The most probable cause is

foreign particles stuck in the master cylinder compensating port.

A hydraulic system referred to as a 'power pack' system will

have all hydraulic power components located in one unit.

When servicing a strut, the correct instructions can be found where?

in the Aircraft Maintenance Manual.

Instructions concerning the type of fluid and amount of air pressure to be put in a shock strut are found

in the aircraft manufacturer's service manual.

An automatic damping action occurs at the steering damper if for any reason the flow of high-pressure fluid is removed from the

inlet of the steering damper.

What is the purpose of chines on Aircraft tires?

to deflect water away from fuselage.

If a fusible plug has allowed a tire to deflate, what is the maintenance action required for that wheel assembly?

to replace the wheel.

What is the function of the cam on a nose wheel strut?

to straighten the wheel out forward.

If the extended longitudinal axis of the main landing gear wheel assemblies intersects aft of the aircraft, the wheels can be termed as having

toe-out.

Aircraft brakes that require a large volume of fluid to operate may?

use power brake control valves.

To prevent a very rapid extension of an oleo shock strut after initial compression resulting from landing impact,

various types of valves or orifices are used which restrict the reverse fluid flow.

Overinflated aircraft tires may cause damage to the

wheel flange.

In brake service work, the term 'bleeding brakes' is the process of

withdrawing fluid from the system for the purpose of removing air that has entered the system.

If an airplane equipped with master cylinders and single-disk brakes has excessive brake pedal travel, but the brakes are hard and effective, the probable cause is

worn brake linings.