Mixed Deck — All A&P Topics Flashcards

What does a variable-displacement hydraulic pump do when system demand is low?

Answer: Reduces its output volume while maintaining system pressure

A variable-displacement pump adjusts its output volume (stroke) to match demand, maintaining pressure while minimizing power consumption.

A technician needs to find approved repair procedures for a damaged main structural member on a specific large aircraft. Which of the following documents should be consulted first?

Answer: The manufacturer's Structural Repair Manual (SRM)

The Structural Repair Manual (SRM) is the primary document issued by the aircraft manufacturer that contains detailed information, limitations, and approved procedures for repairing the aircraft's primary and secondary structures. While AC 43.13-1B provides acceptable techniques for non-pressurized aircraft when no manufacturer instructions are available, the SRM is always the first and authoritative source for a specific aircraft model.

Which document specifies maintenance requirements for a specific aircraft?

Answer: Aircraft Maintenance Manual

The Aircraft Maintenance Manual (AMM) is the definitive document provided by the aircraft manufacturer, containing detailed instructions for all maintenance, inspection, troubleshooting, and repair procedures specific to that aircraft model. It ensures that maintenance is performed correctly and consistently, which is essential for maintaining the aircraft's airworthiness and compliance with design specifications. Other documents like the Pilot's Operating Handbook serve different operational purposes.

What is the function of the 'beta range' on a turboprop propeller control system?

Answer: To allow direct manual control of blade angle below the normal governing range

The beta range allows the pilot to manually control blade pitch below the normal governing range, enabling ground fine pitch, zero thrust, and reverse pitch for ground maneuvering.

Per 14 CFR Part 43, what action is required after performing maintenance on an aircraft fuel system that could affect airworthiness?

Answer: A functional test run must be performed and a return-to-service entry made in the aircraft maintenance records

After fuel system maintenance, the mechanic must perform an operational check of the repaired portion, confirm airworthiness, and make a proper maintenance record entry per 14 CFR 43.9 before return to service.

Which of the following defines the imaginary vertical plane from which all horizontal measurements of arm are taken for weight and balance purposes?

Answer: Datum

The Datum is an imaginary vertical plane or line established by the manufacturer from which all horizontal distances (arms) are measured for weight and balance calculations. Its location is specified in the aircraft's Type Certificate Data Sheet (TCDS) or flight manual.

What is the primary function of the aircraft's carburetor?

Answer: To mix air and fuel for combustion

In piston aircraft engines, the carburetor is a device that precisely mixes air with fuel in the correct proportions before the mixture enters the engine cylinders for combustion. It vaporizes the fuel and blends it with incoming air, creating a combustible mixture that powers the engine. This process is crucial for engine operation, performance, and fuel efficiency.

What is the primary purpose of an Airworthiness Directive (AD)?

Answer: To mandate corrective action for safety issues

Airworthiness Directives (ADs) are legally binding regulations issued by the FAA (or other national aviation authorities) to correct unsafe conditions found in aircraft, engines, propellers, or components. They mandate specific inspections, repairs, or modifications that must be performed to ensure continued airworthiness and prevent potential accidents. Compliance with all applicable ADs is mandatory for an aircraft to be considered airworthy and legally flown.

What is the minimum acceptable octane rating for an engine placarded for 100LL if 100LL is unavailable?

Answer: A higher-octane grade such as 100/130 may be substituted; lower grades are not permitted

An engine requiring 100LL may use higher-octane aviation grades as an upward substitution, but lower-octane fuels risk detonation damage.

What class of fire extinguisher is appropriate for a hydraulic fluid fire?

Answer: Class B extinguisher (for flammable liquids)

Hydraulic fluid is a flammable liquid (Class B fire hazard), so a Class B extinguisher such as CO2 or dry chemical is used.

What is the purpose of the turbocharger in an aircraft engine?

Answer: To compress intake air for better performance at altitude

A turbocharger is a forced induction device used in aircraft engines to improve performance, especially at higher altitudes where air density is lower. It uses exhaust gases to spin a turbine, which in turn drives a compressor to force more air into the engine's cylinders. This increases the air pressure and density in the intake manifold, allowing the engine to produce more power and maintain performance as altitude increases.

What material are most modern aircraft hydraulic lines made from in high-pressure sections?

Answer: 21-4N stainless steel or titanium tubing

High-pressure hydraulic lines in areas subject to vibration and high stress are made from corrosion-resistant steel (CRES) or titanium alloy tubing rated for the system pressure.

What is the purpose of a hydraulic power pack (self-contained unit) on light aircraft?

Answer: It replaces the engine-driven pump with an electric motor-driven pump, reservoir, and valve assembly

A hydraulic power pack integrates an electric pump, reservoir, selector valve, and actuator into one self-contained unit, commonly used for retractable landing gear on light aircraft.

Which of the following non-destructive inspection (NDI) methods is most effective for detecting minute surface and near-subsurface cracks in a conductive turbine engine component, such as a turbine disk, often without requiring its complete removal from the engine?

Answer: Eddy Current Inspection

Eddy current inspection uses electromagnetic induction to detect surface and near-subsurface flaws in conductive materials. It is highly sensitive to small cracks and is a preferred method for inspecting critical components like turbine disks and blades in-situ. Borescope is a visual method, tap testing is for composites, and magnetic particle inspection requires the part to be ferrous and is primarily for surface-breaking flaws.

When weighing an aircraft, the weight of chocks and other equipment used to hold the aircraft on the scales is known as what?

Answer: Tare weight

Tare weight is the weight of any chocks, blocks, or other devices used to hold the aircraft on the scales. This weight must be subtracted from the scale readings to obtain the actual net weight of the aircraft.

An aircraft reciprocating engine has undergone a 'top overhaul.' Which of the following tasks would typically be included in this procedure?

Answer: Removing and reconditioning the cylinders, pistons, and valve-operating mechanisms.

A top overhaul involves work on the parts on top of the crankcase without completely disassembling the engine. This typically includes removing cylinders for reconditioning, replacing or reconditioning pistons and rings, and servicing the valve-operating mechanism.

Which of the following defines a "major overhaul" of a reciprocating engine according to FAA guidance?

Answer: The complete disassembly, inspection, repair as necessary, reassembly, and testing of an engine to the manufacturer's specified fits and limits.

A major overhaul consists of the complete disassembly of an engine, followed by inspection, repair as necessary, reassembly, testing, and approval for return to service within the manufacturer's specified fits and limits, which can be new or serviceable limits.

When servicing an aircraft pneumatic system's air bottle, what must a technician verify before removing the filler valve?

Answer: That the bottle pressure has been bled to zero

The high-pressure air bottle must be fully depressurized to zero before removing any fittings or the filler valve to prevent a dangerous pressure release.

When must the fuel cap be replaced on an aircraft with an integral (wet wing) fuel tank after servicing?

Answer: Immediately after fueling; the tank must not be left uncapped for any reason during maintenance breaks

Fuel caps must be reinstalled and secured immediately after servicing to prevent fuel spillage, contamination, or vapor ignition, and the aircraft must not be left unattended with open fuel caps.

Which component transfers cockpit control inputs to the flight surfaces?

Answer: Control linkage system

The control linkage system, often consisting of cables, pushrods, pulleys, and bellcranks, mechanically connects the pilot's controls in the cockpit (yoke/stick, rudder pedals) to the aircraft's primary and secondary flight control surfaces (ailerons, elevator, rudder, flaps). This system translates the pilot's physical inputs into precise movements of the control surfaces, allowing for accurate manipulation of the aircraft's flight path and attitude.