FAA Aviation Mechanic – ACS Airman Certification Standards Knowledge Test — Questions and Answers

Question 1: How does technology impact modern hydraulic & pneumatic systems practices?

Technology has made professional expertise unnecessary
Technology has no impact on this field
Technology improves accuracy, efficiency, and capabilities while requiring new skills and knowledge (Correct answer)
Only large organizations benefit from technology in this field

Correct answer: Technology improves accuracy, efficiency, and capabilities while requiring new skills and knowledge

Technological advances have transformed professional practice by improving diagnostic capabilities, data analysis, documentation, and efficiency while requiring practitioners to develop new competencies.

Question 2: Which type of structural damage is classified as 'negligible' and requires no repair according to the aircraft SRM?

Dents with sharp radii at the bottom
Any corrosion visible to the naked eye
Minor scratches or nicks that do not exceed allowable depth limits (Correct answer)
A crack that has been stop-drilled

Correct answer: Minor scratches or nicks that do not exceed allowable depth limits

Negligible damage is surface damage within manufacturer-specified allowable limits that does not affect structural integrity and requires no repair.

Question 3: How should discrepancies be documented during inspection?

By verbal communication only
In maintenance logbooks (Correct answer)
On personal notes
Only after repairs

Correct answer: In maintenance logbooks

All discrepancies should be clearly recorded in the maintenance records/logbooks.

Question 4: Which of the following is classified as a major alteration to an airframe under 14 CFR Part 43, Appendix A?

Installing a new wing tip of different design than original (Correct answer)
Lubricating flight control cables
Replacing a worn tire
Replacing a cracked windshield with the same OEM part

Correct answer: Installing a new wing tip of different design than original

Appendix A to Part 43 lists installing a wing tip of different design than originally approved as a major alteration because it affects structural or aerodynamic performance.

Question 5: What is the purpose of a penetrameter (Image Quality Indicator, IQI) in radiographic testing?

To calibrate the X-ray machine voltage and current settings
To verify that the radiograph has sufficient sensitivity and quality to detect a defined minimum flaw size (Correct answer)
To measure the total radiation dose received by the technician
To remove scattered radiation artifacts from the film

Correct answer: To verify that the radiograph has sufficient sensitivity and quality to detect a defined minimum flaw size

An IQI/penetrameter is placed on the part during exposure; its visibility on the finished radiograph confirms that the technique has adequate sensitivity to detect the minimum required discontinuity size.

Question 6: When installing a hydraulic fitting using the B-nut (union nut) method on a flared tube, what is the correct sequence?

Tighten the B-nut first to seat the flare, then back off and retighten to torque
Flare the tube first, then thread the B-nut over the flared end
Slide the B-nut onto the tube before flaring, then flare the tube and tighten (Correct answer)
Install B-nut, then flare the tube, then tighten

Correct answer: Slide the B-nut onto the tube before flaring, then flare the tube and tighten

The B-nut must be slid onto the tube before flaring because the nut cannot pass over a completed flare, making pre-positioning mandatory.

Question 7: What is the most important ethical consideration for ACS professionals in hydraulic & pneumatic systems?

Sharing all client information publicly
Maximizing personal profit from each engagement
Avoiding all challenging work assignments
Maintaining objectivity, integrity, and confidentiality in all professional work (Correct answer)

Correct answer: Maintaining objectivity, integrity, and confidentiality in all professional work

ACS professionals must maintain the highest ethical standards including objectivity, integrity, and confidentiality to protect clients and uphold professional credibility.

Question 8: Under 14 CFR 65.81, a certificated mechanic may exercise the privileges of their certificate only if they have:

Performed work in their certificate's category within the preceding 24 months (Correct answer)
Served as a pilot-in-command within the preceding 6 months
Attended an FAA safety seminar within the preceding 12 months
Passed a practical test within the last 24 months

Correct answer: Performed work in their certificate's category within the preceding 24 months

14 CFR 65.81 requires that a mechanic have performed work in the applicable category or subcategory within the preceding 24 months to exercise certificate privileges.

Question 9: Which NDT method is most appropriate for detecting internal voids and delaminations in composite aircraft structures?

Magnetic particle inspection
Eddy current inspection
Dye penetrant inspection
Ultrasonic inspection or tap testing (Correct answer)

Correct answer: Ultrasonic inspection or tap testing

Ultrasonic testing and tap testing are the primary methods for detecting internal defects such as voids and delaminations in composite structures.

Question 10: Which component in a pneumatic system performs the same function as a hydraulic system relief valve?

Pressure regulator
Filter/separator
Pressure relief valve (Correct answer)
Check valve

Correct answer: Pressure relief valve

A pneumatic pressure relief valve protects the system from overpressure just as a hydraulic relief valve does, opening to vent excess pressure to atmosphere.

Question 11: An aircraft operating with a CG aft of the aft limit will most likely experience:

Reduced stall speed and improved climb
Improved fuel efficiency with no safety risk
Reduced longitudinal stability and possible unrecoverable pitch-up (Correct answer)
Nose-heavy handling that requires constant back pressure

Correct answer: Reduced longitudinal stability and possible unrecoverable pitch-up

An aft CG reduces or eliminates longitudinal static stability, making recovery from a stall or upset potentially impossible.

Question 12: Which method is best for locating hydraulic leaks?

Visual and tactile inspection (Correct answer)
X-ray scanning
Ultrasonic testing
Thermal imaging

Correct answer: Visual and tactile inspection

Visual inspection and tactile checks are standard for detecting leaks in hydraulic systems.

Question 13: An aircraft landing gear extends normally but the green 'gear down and locked' light does not illuminate. The FIRST troubleshooting step should be:

Check the position switch and wiring circuit associated with the indicator light
Assume the gear is down and locked since it extended normally
Manually verify gear position via the viewing port and check the indicator light bulb (Correct answer)
Perform an emergency landing immediately

Correct answer: Manually verify gear position via the viewing port and check the indicator light bulb

The safest first step is to visually verify gear position via mirror or viewing port, then check if the indicator bulb is burned out before assuming a more serious fault.

Question 14: Airworthiness Directives (ADs) issued by the FAA are:

Legally mandatory corrective actions for identified unsafe conditions (Correct answer)
Recommended practices that operators may choose to follow
Manufacturer service bulletins incorporated by reference
Advisory-only notices for aging aircraft

Correct answer: Legally mandatory corrective actions for identified unsafe conditions

ADs are legally mandatory regulations issued under 14 CFR Part 39 that require specific corrective actions to address unsafe conditions in aircraft or components.

Question 15: A 10-lb item is added at a station 50 inches aft of the CG. What is the moment change?

500 in-lb forward
500 in-lb aft (Correct answer)
50 in-lb aft
100 in-lb aft

Correct answer: 500 in-lb aft

Moment change = Weight × Arm from CG = 10 × 50 = 500 in-lb acting aft, tending to move the CG aft.

Question 16: When is it mandatory to bond and ground an aircraft during fueling?

Only when fueling turbine aircraft
Grounding is optional if fueling from a bonded fuel truck
Only when fueling in dry climates with low humidity
Always, before fueling begins, to prevent static discharge ignition of fuel vapors (Correct answer)

Correct answer: Always, before fueling begins, to prevent static discharge ignition of fuel vapors

Bonding and grounding are always required before fueling to equalize static electrical charges and prevent sparks that could ignite fuel vapors.

Question 17: A mechanic notices an aircraft's compass reads 10 degrees off during a compass swing. What is the appropriate corrective action?

Adjust the compensation screws and update the compass correction card (Correct answer)
Replace the compass immediately
Declare the compass unserviceable if error exceeds 5 degrees
File a maintenance discrepancy and allow the pilot to compensate mentally

Correct answer: Adjust the compensation screws and update the compass correction card

Compass deviation within allowable limits can be corrected by adjusting the compensating magnets and must be documented on an updated compass correction card.

Question 18: What is the purpose of a flow control valve in a hydraulic system?

Reduce system pressure to a lower value for downstream components
Prevent reverse fluid flow through a hydraulic line
Control the rate of actuator movement by limiting fluid flow regardless of pressure differential (Correct answer)
Block fluid flow completely when a system is not in use

Correct answer: Control the rate of actuator movement by limiting fluid flow regardless of pressure differential

A flow control valve meters fluid flow rate to an actuator, controlling movement speed independently of the pressure differential across the valve.

Question 19: FAA Form 337 (Major Repair and Alteration) must be submitted to the FAA within:

24 hours of return to service
90 days of work completion
Immediately before the first flight after the work
30 days of work completion (Correct answer)

Correct answer: 30 days of work completion

14 CFR 43.9 and related regulations require Form 337 to be submitted to the FAA Aircraft Registration Branch within 30 days after the work is approved for return to service.

Question 20: On a radiographic film, a darker area (higher film density) typically indicates what about the inspected material?

Greater material thickness or higher density in that area
A void, crack, or area of reduced material density allowing more radiation to pass through (Correct answer)
A surface contaminant blocking radiation
Correct exposure with no defects present

Correct answer: A void, crack, or area of reduced material density allowing more radiation to pass through

Darker areas on radiographic film indicate that more radiation reached the film in those regions, which occurs where material density is lower — such as at voids, cracks, or inclusions of lower-density material.

Question 21: Which item is mandatory for safe evacuation?

Oxygen mask
Emergency exits (Correct answer)
First aid kit
Survival beacon

Correct answer: Emergency exits

Clearly marked and accessible emergency exits are critical for safe evacuation.

Question 22: How does technology impact modern electrical systems & avionics practices?

Technology improves accuracy, efficiency, and capabilities while requiring new skills and knowledge (Correct answer)
Technology has no impact on this field
Only large organizations benefit from technology in this field
Technology has made professional expertise unnecessary

Correct answer: Technology improves accuracy, efficiency, and capabilities while requiring new skills and knowledge

Question 23: What is the advantage of a brake-by-wire (electro-hydraulic) braking system compared to a conventional hydraulic brake system?

Eliminates the need for hydraulic fluid entirely by using electric motors
Provides faster and more precise brake pressure modulation for anti-skid performance (Correct answer)
Reduces aircraft weight by using smaller diameter brake lines
Allows the pilot to apply greater mechanical advantage to brake pedals

Correct answer: Provides faster and more precise brake pressure modulation for anti-skid performance

Electro-hydraulic brake systems use electronic control to modulate hydraulic pressure with greater speed and precision than mechanical inputs alone, improving anti-skid performance.

Question 24: Which tool is commonly used to check continuity in electrical circuits?

Torque wrench
Rivet gun
Multimeter (Correct answer)
Caliper

Correct answer: Multimeter

A multimeter is used to check continuity and diagnose electrical faults.

Question 25: What is the minimum dwell time typically specified for dye penetrant inspection of standard discontinuities in aluminum alloy parts?

5 to 30 minutes (Correct answer)
1 to 2 hours
30 seconds
1 minute

Correct answer: 5 to 30 minutes

For most aluminum alloy parts, penetrant dwell times typically range from 5 to 30 minutes to allow adequate capillary action into discontinuities, as specified by the applicable process specification.

Question 26: A Designated Engineering Representative (DER) has authority to:

Grant IA certificates to mechanics
Perform annual inspections on all aircraft types
Issue Airworthiness Directives
Approve technical data for major repairs and alterations on behalf of the FAA (Correct answer)

Correct answer: Approve technical data for major repairs and alterations on behalf of the FAA

DERs are delegated by the FAA to approve engineering data, which can serve as the approved data basis for major repairs and alterations.

Question 27: An aircraft fuel-injected engine that runs rough at cruise power but smoothly at full throttle most likely has:

A partially blocked fuel injector nozzle causing a lean condition at cruise (Correct answer)
Incorrect ignition timing
A malfunctioning magneto
An air leak in the intake manifold

Correct answer: A partially blocked fuel injector nozzle causing a lean condition at cruise

A partially blocked injector creates a lean mixture in one cylinder that is more pronounced at cruise power settings where fuel flow is lower, causing rough running.

Question 28: What is the purpose of a fuel crossfeed system on a multi-engine aircraft?

To dump fuel overboard in an emergency
To preheat fuel in cold weather
To feed both engines from either tank to manage fuel load or feed a live engine from any tank after an engine failure (Correct answer)
To transfer fuel only to the landing gear hydraulic reservoir

Correct answer: To feed both engines from either tank to manage fuel load or feed a live engine from any tank after an engine failure

A crossfeed system allows either engine to draw from any tank, balancing fuel loads and enabling a surviving engine to draw from the opposite side's tank after an engine failure.

Question 29: When bleeding an aircraft hydraulic system, why is it important to work from the component farthest from the reservoir first?

To ensure maximum fluid velocity through the lines
To allow gravity to pull fluid through the system naturally
To purge all air systematically toward the reservoir and prevent air pockets (Correct answer)
To protect the reservoir from contamination during bleeding

Correct answer: To purge all air systematically toward the reservoir and prevent air pockets

Bleeding from the farthest point ensures air bubbles are progressively pushed back toward the reservoir rather than trapped in the system.

Question 30: When performing a 100-hour inspection on a reciprocating engine, a mechanic finds the oil consumption has doubled since the last inspection. The most likely cause is:

A clogged oil filter
Using the wrong grade of oil
Worn or stuck piston rings (Correct answer)
Incorrect oil pressure setting

Correct answer: Worn or stuck piston rings

Worn or stuck piston rings allow oil to enter the combustion chamber and be burned, significantly increasing oil consumption.

Question 31: If an aircraft hydraulic system uses MIL-PRF-5606 fluid and is inadvertently serviced with MIL-PRF-83282 fluid, what action is required?

No action; the fluids are completely interchangeable
Replace only the hydraulic pump since it is most susceptible to damage
Simply add the correct fluid to dilute the contamination
Flush the system and replace all seals, as the fluids have different seal compatibility (Correct answer)

Correct answer: Flush the system and replace all seals, as the fluids have different seal compatibility

MIL-PRF-5606 and MIL-PRF-83282 have different base oils and different seal material requirements, requiring a full system flush and seal replacement if mixed.

Question 32: What is the purpose of a pneumatic system bootstrap reservoir?

Store excess bleed air for use during engine failure
Pressurize the reservoir above atmospheric pressure to prevent pump cavitation at altitude (Correct answer)
Cool pneumatic fluid before it enters actuators
Act as an expansion chamber for thermal growth of pneumatic tubing

Correct answer: Pressurize the reservoir above atmospheric pressure to prevent pump cavitation at altitude

A bootstrap reservoir is pressurized above the fluid inlet pressure so the hydraulic or pneumatic pump receives adequate inlet pressure, preventing cavitation at high altitudes.

Question 33: When making a flared tube fitting for an aircraft fuel line, the correct flare angle for AN (Army-Navy) fittings is:

90 degrees
45 degrees
37 degrees (double flare equivalent per AN standard) (Correct answer)
60 degrees

Correct answer: 37 degrees (double flare equivalent per AN standard)

AN (Army-Navy) standard fittings use a 37-degree flare angle, which is different from the 45-degree flare used in automotive applications.

Question 34: Which risk assessment model used in aviation maintenance identifies likelihood and severity to prioritize hazards?

PAVE checklist
DECIDE model
Risk matrix (likelihood × severity) (Correct answer)
5M model

Correct answer: Risk matrix (likelihood × severity)

A risk matrix that evaluates both the likelihood of an event and its potential severity is the standard tool for prioritizing hazards in SMS and maintenance risk management.

Question 35: According to 14 CFR Part 39, compliance with an Airworthiness Directive is:

Advisory for aircraft over 20 years old
Mandatory and legally enforceable (Correct answer)
Required only for commercial operations
Optional if the owner signs a waiver

Correct answer: Mandatory and legally enforceable

ADs are issued under 14 CFR Part 39 and are mandatory federal regulations; non-compliance renders the aircraft unairworthy.

Question 36: What ethical standards guide ACS professionals in their work?

Maximizing personal profit is the primary ethical obligation
Ethics only apply when clients are watching
Ethical standards are suggestions, not requirements
Integrity, objectivity, confidentiality, and professional competence in all engagements (Correct answer)

Correct answer: Integrity, objectivity, confidentiality, and professional competence in all engagements

Professional ethics require maintaining the highest standards of integrity, objectivity, and confidentiality while continuously developing competence.

Question 37: The term 'useful load' is defined as the difference between:

Ramp weight and takeoff weight
Maximum takeoff weight and maximum landing weight
Maximum gross weight and basic empty weight (Correct answer)
Zero fuel weight and landing weight

Correct answer: Maximum gross weight and basic empty weight

Useful load = Maximum Gross Weight – Basic Empty Weight, and represents the total payload the aircraft can carry.

Question 38: When must a mechanic update the aircraft weight and balance records after maintenance?

After every inspection, regardless of work performed
Only when a major alteration or repair changes the aircraft's weight or CG (Correct answer)
Whenever new avionics are inspected but not replaced
Every 100 hours of operation

Correct answer: Only when a major alteration or repair changes the aircraft's weight or CG

FAR 43.9 and related regulations require updating weight and balance data only when a repair or alteration changes the aircraft weight or CG location.

Question 39: What is the moment index, and why is it used?

A scaled-down moment value (moment ÷ a reduction factor) to simplify arithmetic (Correct answer)
A ratio of weight to drag used for performance calculations
The CG position expressed as a percentage of wing chord
The maximum allowable moment for a given weight

Correct answer: A scaled-down moment value (moment ÷ a reduction factor) to simplify arithmetic

A moment index divides the moment by a constant (e.g., 1,000) to produce smaller, easier-to-use numbers on loading charts.

Question 40: How do ACS professionals contribute to organizational success?

By applying specialized knowledge to solve problems, reduce risks, improve processes, and drive strategic outcomes (Correct answer)
Professional expertise has minimal organizational value
Only executives contribute to organizational success
They only perform routine tasks with no strategic impact

Correct answer: By applying specialized knowledge to solve problems, reduce risks, improve processes, and drive strategic outcomes

Certified professionals bring specialized expertise that directly contributes to organizational goals through problem-solving, risk reduction, process improvement, and strategic decision support.

Question 41: What is the impact of regulatory changes on ACS professionals?

Regulatory changes only affect large organizations
Regulatory changes require updating practices, procedures, and documentation to maintain compliance (Correct answer)
Only government employees need to follow regulatory changes
Regulations never change once established

Correct answer: Regulatory changes require updating practices, procedures, and documentation to maintain compliance

Professionals must monitor and adapt to regulatory changes that affect their practice, ensuring continued compliance and effective service delivery.

Question 42: Which type of engine oil system is most commonly used in modern horizontally opposed aircraft engines?

Pressure spray with no sump
Total loss system
Dry sump with remote reservoir
Wet sump (Correct answer)

Correct answer: Wet sump

Most horizontally opposed aircraft engines use a wet sump system where oil is stored in a sump at the bottom of the crankcase.

Question 43: What is the main hazard of moisture contamination in a high-pressure pneumatic system?

Moisture can freeze at altitude, blocking orifices and valves (Correct answer)
Moisture causes pump cavitation at sea level
Moisture increases fluid viscosity, reducing flow rates
Moisture reacts with nitrogen to form corrosive compounds

Correct answer: Moisture can freeze at altitude, blocking orifices and valves

Water moisture in pneumatic lines can freeze at altitude temperatures, blocking critical orifices, valves, and lines, causing system failure.

Question 44: Under the ACS standards, a mechanic must demonstrate knowledge of quality assurance by understanding that an Inspection Authorization (IA) is required to:

Sign off on 100-hour inspection records
Approve an aircraft for return to service after an annual inspection (Correct answer)
Install PMA parts
Perform routine oil changes on turbine engines

Correct answer: Approve an aircraft for return to service after an annual inspection

Annual inspections can only be approved for return to service by a mechanic holding an IA, per 14 CFR 65.95.

Question 45: Which 14 CFR Part governs the certification of aviation mechanics?

Part 43
Part 91
Part 65 (Correct answer)
Part 147

Correct answer: Part 65

14 CFR Part 65 covers airmen other than flight crewmembers, including the certification requirements and privileges of aviation mechanics.

Question 46: When the repair data in the Structural Repair Manual (SRM) does not cover the type or size of damage found, the technician must:

Fabricate a repair based on best engineering judgment and return the aircraft to service
Contact the aircraft manufacturer's engineering department for a specific repair disposition (Correct answer)
Ground the aircraft permanently as it is beyond repair
Use the closest applicable SRM procedure and note any deviations

Correct answer: Contact the aircraft manufacturer's engineering department for a specific repair disposition

When damage exceeds SRM limits or the damage type is not covered, FAA regulations require contacting the Type Certificate holder (manufacturer) for engineering approval of the repair.

Question 47: Why is proper weight and balance critical for aircraft safety?

It only matters for cargo aircraft, not passenger aircraft
An aircraft loaded outside its center of gravity limits may become uncontrollable, leading to a potential crash (Correct answer)
Weight and balance only affects fuel consumption, not safety
Weight and balance calculations are optional for certified mechanics

Correct answer: An aircraft loaded outside its center of gravity limits may become uncontrollable, leading to a potential crash

Proper weight and balance ensures the aircraft's center of gravity remains within approved limits, directly affecting controllability, stability, structural integrity, and performance.

Question 48: What does a negative differential compression reading between cylinder top and side ports indicate?

Piston ring leakage
Exhaust valve leakage (Correct answer)
Head gasket failure
Intake valve leakage

Correct answer: Exhaust valve leakage

Air escaping into the exhaust stack during a differential compression test indicates a leaking exhaust valve.

Question 49: A pilot reports intermittent compass deviation when the landing gear is cycled. What is the most likely cause?

A faulty compass compensation card
Low battery voltage during gear retraction
Excessive ferrous metal near the compass
A chafed wire in the landing gear circuit creating electromagnetic interference (Correct answer)

Correct answer: A chafed wire in the landing gear circuit creating electromagnetic interference

A chafed wire can create intermittent shorts that generate magnetic fields near the compass, causing temporary deviation.

Question 50: What is the purpose of performing a porosity check (resin content test) on a wet layup repair sample panel?

To measure electrical conductivity for lightning strike compliance
To ensure the fiber-to-resin ratio meets structural requirements and voids are minimal (Correct answer)
To verify the fiber orientation matches the parent laminate
To confirm the repair resin is fully cured before service return

Correct answer: To ensure the fiber-to-resin ratio meets structural requirements and voids are minimal

A porosity or resin content check verifies that the repair has the correct fiber volume fraction and void content to meet the structural properties assumed in repair design.

Question 51: How does continuing education benefit ACS professionals?

Continuing education is not needed after certification
Continuing education is purely optional with no benefits
It ensures practitioners stay current with evolving standards, technologies, and best practices (Correct answer)
Only beginners benefit from additional training

Correct answer: It ensures practitioners stay current with evolving standards, technologies, and best practices

Professional fields evolve constantly — continuing education ensures practitioners maintain competence and stay current with industry developments.

Question 52: What document governs the minimum bend radii and tube material specifications for aircraft fluid lines?

NFPA 407
MIL-SPEC-5015 only
FAR Part 21
AC 43.13-1B Chapter 9 and the applicable aircraft maintenance manual (Correct answer)

Correct answer: AC 43.13-1B Chapter 9 and the applicable aircraft maintenance manual

AC 43.13-1B Chapter 9 provides the FAA-accepted data for aircraft plumbing including bend radii, materials, flare types, and installation standards, supplemented by the AMM.

Question 53: What part regulates the speed of a propeller?

Governor (Correct answer)
Throttle
Tachometer
Mixture control

Correct answer: Governor

A governor adjusts the propeller blade angle to control RPM.

Question 54: What is the function of the torque links (scissors) on a nose gear oleo strut?

To connect the steering actuator to the wheel
To prevent strut rotation while allowing vertical movement (Correct answer)
To provide shimmy dampening
To limit strut extension travel

Correct answer: To prevent strut rotation while allowing vertical movement

Torque links (scissors links) connect the upper and lower strut cylinders to prevent rotation while allowing the strut to extend and compress freely.

Question 55: Which type of maintenance record entry is required after completion of a 100-hour inspection?

A field approval form
A signed logbook entry per 14 CFR 43.11 (Correct answer)
A Supplemental Type Certificate
An FAA Form 8130-3

Correct answer: A signed logbook entry per 14 CFR 43.11

14 CFR 43.11 requires a maintenance record entry including the date, aircraft total time, signature, and certificate number after each inspection.

Question 56: What is the purpose of a hydraulic system case drain line on a variable displacement piston pump?

Return low-pressure fluid that bypasses the internal piston seals back to the reservoir (Correct answer)
Supply lubrication fluid to the pump shaft bearing from an external source
Carry pump output to a secondary system during low-demand periods
Vent pressure from the pump housing if the outlet check valve fails

Correct answer: Return low-pressure fluid that bypasses the internal piston seals back to the reservoir

Case drain lines return internal leakage fluid that bypasses piston seals back to the reservoir, preventing case pressure buildup that could damage pump shaft seals.

Question 57: Which organization publishes Service Bulletins (SBs) for type-certificated aircraft, and what is their regulatory status?

The aircraft manufacturer publishes SBs, and compliance is generally recommended but not mandatory unless referenced by an AD (Correct answer)
The FAA publishes SBs, and compliance is always mandatory
The NTSB publishes SBs after accident investigations
ICAO publishes SBs, and compliance is mandatory for international operations

Correct answer: The aircraft manufacturer publishes SBs, and compliance is generally recommended but not mandatory unless referenced by an AD

Manufacturers publish Service Bulletins as recommended actions; they become mandatory only when incorporated into an FAA Airworthiness Directive.

Question 58: Which document establishes the approved data a mechanic must use when performing a major repair?

The aircraft logbook
The parts manual
FAA-approved data such as AMM, SRM, or FAA-accepted engineering order (Correct answer)
The manufacturer's service letter

Correct answer: FAA-approved data such as AMM, SRM, or FAA-accepted engineering order

Major repairs must be performed per FAA-approved data; unapproved data (e.g., service letters alone) is insufficient without FAA acceptance.

Question 59: What does a 'red arc' on an aircraft instrument face represent?

Never-exceed or maximum limit (Correct answer)
Normal operating range
Caution or precautionary range
Manufacturer-recommended cruise range

Correct answer: Never-exceed or maximum limit

A red arc or red radial line on an instrument denotes a never-exceed speed or maximum operating limit that must not be exceeded.

Question 60: To exercise Inspection Authorization (IA) privileges, a mechanic must hold an IA for at least how long before it must be renewed?

6 months
It never expires
24 months
12 months (Correct answer)

Correct answer: 12 months

An Inspection Authorization must be renewed annually (every 12 calendar months) by meeting one of the renewal activity requirements in 14 CFR 65.93.

FAA Aviation Mechanic – ACS Airman Certification Standards Knowledge Test

The FAA Aviation Mechanic knowledge test evaluates candidates on general aviation maintenance principles, airframe systems, fuel/hydraulic systems, and NDT inspection skills required to earn an FAA Mechanic Certificate under the Airman Certification Standards (ACS) framework.

Questions

150 min

Time Limit

70%

To Pass

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