AVM Powerplant Practice Test

These questions are part of the practice quiz. Start practicing

• The compressor stators in a gas turbine engine act as diffusers to
• In an axial-flow turbojet engine, at what point do the highest gas pressures occur?
• Between each row of rotating blades in a turbine engine compressor, there is a row of stationary blades known as what? Choose the term that best describes these stationary blades.
• Which of the following types of combustion sections are used in aircraft turbine engines?
• How does a dual axial-flow compressor improve the efficiency of a turbojet engine?
• Which term describes a severe fretting where metal is transferred from one surface to another?
• Accumulation of contaminants in the compressor blades reduces aerodynamic efficiency. Which statement describes the impact?
• What are the two main sections used to categorize a basic gas turbine engine?
• Which instrument indicates the thrust of a gas turbine engine?
• Which statement best describes a double-entry centrifugal compressor?
• Blade and vane blending is usually performed during overhaul with the engine removed. True or False?
• Who establishes the recommended operating time between overhauls (TBO) of a turbine engine used in general aviation?
• Which variables affect the inlet air density of a turbine engine?
• What must be done after the fuel control unit has been replaced on an aircraft gas turbine engine?
• What is the primary purpose of the tachometer on an axial-compressor turbine engine?
• On an aircraft turbine engine operating at a constant power the application of engine anti-icing will result in
• The velocity of subsonic air as it flows through a convergent nozzle
• Indentations on bearing races caused by high static loads are known as?
• A turbine engine compressor which contains vanes on both sides of the impeller is a
• Which is the ultimate limiting factor of turbine engine operation?
• What is used in turbine engines to aid in stabilization of compressor airflow during low thrust engine operation?
• Which factors affect the thermal efficiency of a turbine engine?
• Severe rubbing of turbine engine compressor blades will usually cause which damage?
• Which turbine engine compressor offers the greatest advantages for both starting flexibility and improved high-altitude performance?
• Which section is associated with increasing the static pressure of the air flow by transforming velocity energy?
• How are combustion liner walls cooled in a gas turbine engine?
• The purpose of a bleed valve located in the beginning stages of the compressor in an aircraft gas turbine engine is to
• Which condition is usually not acceptable to any extent in turbine blades?
• Most exhaust system failures result from thermal fatigue cracking in areas of stress concentration. This condition is usually caused by which factor?
• Which combustion section configuration is used when multiple cans are employed in aircraft engines?
• Which statement about the engine bleed air system is true?
• Turbine nozzle diaphragms located on the upstream side of each turbine wheel are used to
• Which method is used to provide clean air to engines of helicopters and turboprop airplanes that have particle separators installed?
• The function of an APU air inlet plenum is to stabilize the pressure of the air before it enters the compressor.
• The fan rotational speed of a dual axial compressor forward fan engine is the same as the
• Airworthiness Directives of an emergency nature may require immediate compliance upon receipt. True or False?
• Which mark on an engine instrument face indicates a maximum limit for high transients such as starting?
• A weak fuel-to-air mixture along with normal airflow through a turbine engine may result in
• Which of the following is used to monitor the mechanical integrity of the turbines and check engine operating conditions of a turbine engine?
• One function of the nozzle diaphragm in a turbine engine is to
• What is the function of the stator vanes in the compressor?
• Which statement about main bearing oil seals is correct?
• What is meant by a double-entry centrifugal compressor?
• Which contains approved data for performing a major repair to an aircraft engine?
• Which two elements make up the axial-flow compressor assembly?
• Anti-icing of jet engine air inlets is commonly accomplished by which method?
• When the leading edge of a first-stage turbine blade shows stress rupture cracks, which condition should be suspected?
• What is the primary efficiency improvement provided by a dual axial-flow compressor?
• In a turbine engine with a dual-spool compressor the low speed compressor
• What is the primary purpose of shrouds on the turbine blades of an axial-flow engine?
• Which parameter does fuel flow indication data primarily represent for engine management?
• Which section is FAA-approved for continued airworthiness documentation?
• What is the primary purpose of the tachometer on an axial-compressor turbine engine?
• Dirt particles in the air entering the compressor will form a coating on all but which component?
• What is the general objective of a turbine engine oil analysis program?
• Shrouded turbine rotor blades primarily provide which benefit?
• What is the function of the Inlet Guide Vane Assembly on an axial-flow compressor?
• In the turbine section, the stators are designed to
• The fuel flowmeter indicator rotor and needle for a motor-impeller and turbine indicating system is driven by what?
• What motor type is used in most electric tachometers?
• Regarding turbine blade serviceability, which statement is true?
• In the two-section model of a gas turbine engine, the statements that the cold section includes the engine inlet, compressor, and turbine; and the hot section includes the combustor, diffuser, and exhaust are true. Regarding the above statements, which is true?
• Which instrument indicates thrust of a gas turbine engine?
• In an axial-flow compressor, which component is primarily responsible for guiding airflow to the rotor blades at the proper angle?
• What instrument on a gas turbine engine should be monitored to minimize the possibility of a 'hot' start?
• Which of the following is NOT a design goal for thrust reverser systems?
• Standard sea level pressure is
• Which condition commonly leads to compressor stall in a turbine engine?
• Turbine blades are generally more susceptible to operating damage than compressor blades because of
• To accomplish internal inspection of an assembled turbine engine, which component would you most likely inspect with a borescope?
• Why do helicopters require a minimum of two synchronous tachometer systems?
• In an APU with a free turbine and a load compressor, the primary function of the load compressor is to
• Airworthiness standards for small airplanes with nine or fewer seats in the normal utility and acrobatic categories are found in which regulation?
• Dirt particles in the air entering the compressor will form a coating on all but which component?
• The tachometer indicator is responsive to changes in which parameter?
• Which outcome is achieved by the cooldown period prior to shutdown?
• The number of rows of stages in an axial-flow compressor is determined by
• The RPM indication of a synchronous AC motor-tachometer is determined by the frequency of what?
• What is the function of a blast tube as found on aircraft engines?
• What is the purpose of the dump valve used on aircraft gas turbine engines?
• What is the function of the Inlet Guide Vane Assembly on an Axial-Flow Compressor?
• Which statement about axial-flow vs centrifugal compressors is correct?
• In maintenance manuals for some twin-spool engines, turbine discharge pressure is identified as Pt7. Which option correctly reflects this labeling?
• A common type of electrically operated oil temperature gauge utilizes which circuit?
• Which statement correctly describes the nozzle diaphragm function?
• Stator blades in the compressor section of an axial-flow turbine engine
• Where do stress rupture cracks usually appear on turbine blades?
• Which statement about turbine discharge pressure measurement is true?
• Which of the following would most likely cause an increase in exhaust gas temperature (EGT) in a turbine engine?
• The exhaust section of a turbine engine is designed to do what?
• Which turbine blade type is most commonly used in aircraft jet engines?
• Which section in the Instructions for Continued Airworthiness is FAA approved?
• Regarding powerplant installation on aircraft with a Standard Airworthiness Certificate, which statement is true?
• The abbreviation Pt7 used in turbine engine terminology means
• A condition known as hot streaking in turbine engines is caused by
• The compression ratio of an axial-flow compressor is a function of the
• In turbine engine terminology, Pt7 refers to
• What is the proper operating sequence when using thrust reversers to slow an aircraft after landing?
• Which of the following can inspect and approve an engine major repair for return to service?
• In some twin-spool manuals, turbine discharge pressure is labeled Pt2. Which option best identifies this label?
• On APU's equipped with a free turbine and load compressor the primary function of the load compressor is to
• Which parameter most directly influences turbine engine thermal efficiency besides turbine inlet temperature?
• Which two methods are commonly used to remove dirt from turbojet compressor blades?
• The non-rotating axial-flow compressor airfoils in an aircraft gas turbine engine are called what?
• Which statement is true regarding jet engines?
• Reduced blade vibration and improved airflow characteristics in gas turbines are brought about by
• When an engine with a subsonic divergent type inlet duct is running in place at high speed on the ground, the air pressure within the inlet is what?
• Thrust reversers utilizing a pneumatic actuating system usually receive operating pressure from which source?
• Which condition may cause a lean die-out in a turbine engine with normal airflow?
• The diffuser section of a jet engine is located between
• The velocity of supersonic air as it flows through a divergent nozzle
• In a centrifugal compressor, which two components are fundamental to its function?
• What is the purpose of a bellmouth inlet?
• A turbine engine hot section is particularly susceptible to which kind of damage?
• What publication is used for guidance to determine whether a power plant repair is major or minor?
• The recurrent ingestion of dust or other fine airborne particulates into a turbine engine can result in what?
• An exhaust cone placed aft of the turbine in a jet engine will cause the pressure in the first part of the exhaust duct to
• Hot spots in the combustion section of a turbojet engine are possible indicators of which issue?
• Powerplants installed on airplanes with a Standard Airworthiness Certificate must have which certification status?
• Which statement best describes the function of the exhaust section in a turbine engine?
• What device helps stabilize compressor airflow during low thrust operation?
• In a centrifugal compressor, what are the two functional elements?
• The pressure of supersonic air as it flows through a divergent nozzle
• Blending of blades and vanes in a turbine engine is usually performed how?
• The turbine section of a turbine engine comprises which two main components?
• What type igniter plug is used in the low tension ignition system of an aircraft turbofan engine?
• Which statement best describes how a turbine engine tachometer is calibrated?
• Regarding the statements about engine pressure ratio (1) and (2), which is true?
• Which of the following types of electric motors are commonly used in electric tachometers?
• In the dual axial-flow or twin-spool compressor system, the first stage turbine drives the
• Which factor most commonly causes exhaust system thermal fatigue cracking, as described in the material?
• Which of the following is a good indication of a malfunctioning fuel nozzle when inspecting the exhaust section of an aircraft turbine engine?
• Which instrument fault condition requires replacement of the instrument?
• Which statement is true regarding the air passing through the combustion section of a jet engine?
• The turbine section of a jet engine primarily drives which other section?
• Which combination correctly lists the three types of turbine blades?
• What part of an aircraft in flight will begin to accumulate ice before any other?
• Under standard atmospheric conditions, the standard sea level temperature is:
• What type of turbine blade is most commonly used in aircraft jet engines?
• What is the major function of the turbine assembly in a turbojet engine?
• For engine pressure ratio, which statement is true?
• In a dual axial-flow compressor, the first stage turbine drives
• Which statement about thermocouple leads is correct?
• In an axial-flow turbojet, the location of maximum gas pressure is at the boundary of which component?
• Which indicator would be used to estimate remaining endurance at the current power setting?
• When cooling the APU before shutdown is necessary, which action should be taken?
• Discharge-end stator vanes misalignment would most likely cause which issue?
• Instruments that provide readings of low or negative pressure, such as manifold pressure gauges, are usually what type?
• Which marking method is generally not acceptable on turbine engine components exposed to high temperatures?
• The turbine nozzle diaphragms are located on the upstream side of each turbine wheel. They are used to
• Turbine engine EGT thermocouples are constructed of which materials?
• In thrust reversing, cascade vanes are used to accomplish which?
• Which statement best reflects the function of static vanes in a turbine compressor system when considering performance impact?
• In a jet engine, which component experiences the highest heat-to-metal contact?
• In the proper starting sequence for a turbojet engine, which component is activated second?
• The purpose of an engine/inlet anti-ice system is primarily to
• When must an Airworthiness Directive (AD) be complied with after it becomes effective?
• In an axial-flow compressor, a pressure stage is formed by
• Severe rubbing of compressor blades will usually cause which damage?
• The rearward thrust capability of an engine with the thrust reverser system deployed is:
• Compressor field cleaning on turbine engines is performed primarily to prevent which outcome?
• At what stage in a turbine engine are gas pressures the greatest?
• During routine maintenance, the case and liner are removed and installed as a single unit for which type of turbine engine combustion chamber?
• In terms of engine performance, which statement best describes the relationship to thermal efficiency?
• Which component is described as the stationary part in the axial-flow compressor?
• For high-altitude operation of two-spool compressors, which statement is true?
• What is a typical purpose of a dump valve in a gas turbine engine?
• The fuel flow indication data sent from moto driven impeller and turbine and motorless type fuel flow transmitters measures which parameter?
• Among the listed types of damage, which is most associated with the turbine engine hot section?
• Which components are included in the hot section of a basic gas turbine engine according to the description?
• The APU generator is identical to engine-driven generators. Which statement is true about APU generators?
• Where is the highest gas pressure in a turbojet engine?
• Defective plating or excessive loads can cause the breaking loose of small metal pieces from coated surfaces. What is this phenomenon called?
• Which document is FAA-approved data used for performing major repairs on an aircraft engine?
• In an axial-flow compressor, one purpose of the stator vanes at the discharge end of the compressor is to
• In an axial-flow compressor, which component remains stationary while the other rotates?
• Which of the following describes a consequence of deploying thrust reversers at low ground speeds?
• Engine pressure ratio is defined as the ratio of which parameters?
• The pressure of subsonic air as it flows through a convergent nozzle:
• What is the primary factor that controls the pressure ratio of an axial-flow compressor?
• What is the possible cause when a turbine engine indicates no change in power setting parameters but oil temperature is high?
• Why do some turbine engines have more than one turbine wheel attached to a single shaft?
• Which type of instrument is typically used to measure relatively high fluid pressures such as oil pressure gauges?
• The airworthiness standards for the issue of type certificates for small airplanes with nine or less passenger seats in the normal utility and acrobatic categories may be found in the
• Which statement is correct concerning a thermocouple-type temperature indicating instrument system?
• What is the profile of a turbine engine compressor blade?
• Between each row of rotating blades in a turbine engine compressor, there is a row of stationary blades which act to diffuse the air. These stationary blades are called
• Which instrument condition is acceptable and does not require immediate correction?
• The engine pressure ratio indicator is a direct indication of which of the following?
• If a turbine engine is unable to reach takeoff EPR before its EGT limit is reached, which of the following is a likely indication?
• In a thrust reversing system, what is the purpose of cascade vanes?
• During turbine engine startup, a hung start is indicated by which condition?
• Which marking material is used to identify turbine components exposed to high temperatures?
• Hot spots on the tail cone are an indicator of malfunction in which engine subsystem?
• In a turbine engine, gas pressures are greatest at which stage?
• Hot section inspections for many modern turbine engines are performed on what basis?
• Vortex dissipator systems use which method to prevent FOD?
• Two statements about welding and straightening turbine engine rotating airfoils were evaluated. Which option is correct?
• Which instrument condition would be considered acceptable and not require immediate correction?
• Generally, when maximum APU shaft output power is being used in conjunction with pneumatic power
• The two types of centrifugal compressor impellers are
• The air passing through the combustion chamber of a turbine engine is used for which two main purposes?
• What is one purpose of the stator blades in the compressor section of a turbine engine?
• Engines using cold stream, or both cold and hot stream reversing include:
• During turbine engine operation, which parameter is considered the most critical to monitor?
• Which marking method is generally not acceptable on high-temperature turbine components?
• Who establishes mandatory replacement times for critical components of turbine engines?
• An APU is usually rotated during start by which device?
• During turbine engine start, a hot start is indicated by which condition?
• What is the proper starting sequence for a turbojet engine?
• Engine pressure ratio is determined by
• Which statement regarding engine driven propellers is true?
• Which of the following may be used to accomplish internal inspection of an assembled turbine engine?
• The computerized fuel system (CFS) with a totalizer-indicator provides indication of how many of the following?
• What does the term 'totalizer' refer to in the context of fuel systems?
• Which engine variable is the most critical during turbine engine operation?
• Where is the highest gas pressure in the turbojet engine typically found?
• What maintenance record(s) is/are required following a major repair of an aircraft engine?
• Two common methods for removing dirt deposits from compressor blades are a fluid wash and an abrasive grit blast. Which statement is true?
• Operating thrust reversers at low ground speeds can sometimes cause:
• The Brayton cycle used in turbine engines is defined as a constant what cycle?
• Fuel scheduling during APU start and under varying pneumatic bleed and electrical loads is maintained
• The hot section of a turbine engine is particularly susceptible to which kind of damage?
• Engine pressure ratio is defined as the total pressure ratio between which pair of points?
• What is the upper bound of thrust reverser capability as a percentage of the rated thrust in reverse for turbojet airplanes?
• Which statement about turbine engine oil analysis programs is NOT true?
• Welding and straightening turbine engine rotating airfoils are statements evaluated for truth. Which option correctly reflects the given evaluation?
• In which section of a turbojet engine is the jet nozzle located?
• Which is used as the primary thrust indicator in some turbine-powered aircraft?
• Which unit in a tachometer system sends information to the indicator?
• Which statement about engine instrument markings is true?
• In a subsonic flow through a convergent nozzle, the air velocity
• In a shrouded turbine, blade tips form what feature?
• A Bourdon-tube instrument may be used to indicate which of the following?
• What turbine engine section provides for proper mixing of the fuel and air?
• What engine instrument indications may shift when a turbofan engine anti-icing (bleed air) system is turned on ?
• Engine pressure ratio is the total pressure ratio between which two points?
• Airworthiness Directives (ADs) may require immediate compliance for emergency ADs. Which statement is true?
• Which organization is typically responsible for mandating replacement intervals for turbine engine critical components?
• Thrust reversers utilizing a pneumatic actuating system usually receive operating pressure from
• Continued and/or excessive heat and centrifugal force on turbine engine rotor blades is likely to cause which phenomenon?
• If the RPM of an axial-flow compressor remains constant, the angle of attack of the rotor blades can be changed by
• The pressure source for thrust reverser actuators in many engines is typically which system?
• Which component operates at the highest temperatures in a turbine engine?
• Which parameter most influences the operation of an automatic fuel control unit on a turbojet engine?
• In a turbine engine axial-flow compressor, statements: (1) each consecutive pair rotor and stator blades constitutes a pressure stage. (2) The number of rows of stages is determined by the amount of air and total pressure rise required. Regarding the statements
• Vortex dissipator systems are generally activated by
• The function of the exhaust cone assembly of a turbine engine is to
• Which combination of engine instrument indicators may shift when the anti-icing bleed system is activated?
• In a gas turbine engine combustion occurs at a constant
• A severe condition of chafing or fretting in which a transfer of metal from one part to another occurs is called which term?
• During operation, the speed of an APU is best described as which?
• In a turbine engine, where is the turbine discharge pressure indicator sensor typically located?
• The Brayton cycle is known as which type of cycle?
• Which of the following would be a likely engine symptom when operating with a weak fuel-to-air mixture?
• The procedure for removing the accumulation of dirt deposits on compressor blades is called
• Turbine blades are generally more susceptible to operating damage than compressor blades because of
• If during inspection at engine overhaul, ball or roller bearings are found to have magnetism but otherwise have no defects, they
• Usually, most of the load placed on an APU occurs when
• What publication contains the mandatory replacement time for parts of a turbine engine?
• What is the blade tip thickness characteristic of a turbine engine compressor blade?
• Newton's First Law of Motion, generally termed the Law of Inertia, states:
• What is meant by a shrouded turbine?
• What are the two basic elements of the turbine section in a turbine engine?
• What is the function of the stator vane assembly at the discharge end of a typical axial-flow compressor?
• In a centrifugal compressor, the two functional elements are which?
• The vortex dissipators installed on some turbine-powered aircraft to prevent engine FOD utilize which method?
• If oil temperature is high but power setting unchanged, what is the most likely fault?
• The standard sea level temperature under ISA conditions expressed in degrees Fahrenheit is what?
• A cool-off period prior to shutdown of a turbine engine is accomplished in order to
• Which statement about the CFS totalizer-indicator is true?
• Motor-driven impeller and turbine fuel flow transmitters are designed to transmit data
• The RPM indication of a synchronous AC motor-tachometer is governed by the generator
• What is the primary advantage of an axial-flow compressor over a centrifugal compressor?
• Field cleaning is the procedure used to remove dirt deposits from which part of a turbine engine?
• The purpose of a bellmouth compressor inlet is to
• Some engine manufacturers of twin spool gas turbine engines identify turbine discharge pressure in their maintenance manuals as which label?
• Which statement describes the correct procedure for cooling an APU before shutdown related to bleed air?
• What should be done initially if a turbine engine catches fire during starting?
• Which marking material is used to identify turbine engine components exposed to high temperatures?
• The stators in the turbine section of a gas turbine engine
• The stator vanes in an axial-flow compressor perform which energy transformation?
• A primary advantage of the centrifugal-flow compressor is the high pressure rise per stage. True or False?
• What is the purpose of the diffuser section in a turbine engine?
• The exhaust gas temperature (EGT) indicator on a gas turbine engine provides a relative indication of which parameter?
• What is the first engine instrument indication of a successful start of a turbine engine?
• A divergent nozzle in a jet engine is used to accelerate exhaust flow to higher speeds by
• When reinstalling a turbine blade after inspection, into which slot must the blade be placed?
• Statements about turbine engine indicators: which is true?
• Indentations on bearing races caused by static loads are known as?
• Three types of turbine blades are
• Which system provides pneumatic pressure for thrust reverser actuators?
• Which blade design is associated with reduced vibration in turbine engines?
• Which of the following indicates that a combustion chamber of a jet engine is not operating properly?
• For particle separators in helicopters, the removal of particulates relies on which principle?
• The component that operates at the highest temperatures in the turbine engine is the?
• Main bearing oil seals used with turbine engines are usually what type(s)?
• What are the two functional elements in a centrifugal compressor?
• The engine pressure ratio indicator directly indicates which of the following?
• What is the primary function of the exhaust cone assembly in a turbine engine?
• When starting a turbine engine, the starter should be disengaged:
• When aircraft turbine blades are subjected to excessive heat stress, what type of failures would you expect?
• In what units are turbine engine tachometers calibrated?
• Which statement about thrust reverser systems is true?
• Regarding powerplant instrument range markings statements: (1) show whether current state is normal, acceptable for a limited time, or unauthorized. (2) Based on installed engine operating limits which may not exceed (but are not necessarily equal to) those limits shown on the engine Type Certificate Data Sheet. Which of the following is true?
• In a turbine engine, which component is designed to increase the pressure of the incoming air before combustion?
• Hot spots in the combustion section are most likely indicative of which issue?
• An advantage of the centrifugal-flow compressor is its high which characteristic?
• Thrust reversers that use a pneumatic actuating system usually receive operating pressure from which source?
• An advantage of the axial-flow compressor is its
• Thrust reversers on turbojet powered airplanes can produce between what percent of rated thrust in the reverse direction?