Oxford Reciprocating Engines Practice Test

These questions are part of the practice quiz. Start practicing

• What does the "anti-knock" value of a fuel indicate?
• The fuel flow to a piston engine varies according to which of the following factors?
• If the volume of a gas is halved during compression, what happens to its pressure?
• In a complex engine, as RPM increases, what may happen to the ignition timing?
• If engine power is increased with the propeller lever in the constant speed range, what happens?
• What does the angle of attack of a fixed pitch propeller depend on?
• Why does the inlet valve open before T.D.C. during the exhaust stroke?
• Weakening the mixture below the best fuel/air ratio will cause the engine power to:
• What does the Automatic Boost Control Unit operate?
• What is the potential impact of having an exhaust valve that sticks open?
• With an increase in outside air temperature, what happens to specific fuel consumption?
• Why is tappet clearance provided in a piston engine?
• What are the effects on an engine of a low power, high speed descent?
• What is the most probable cause of small fluctuations in oil pressure?
• Which fuel grade is commonly used in typical aircraft engines?
• A turbo-charger which is designed to maintain sea level pressure at altitude is termed:
• When is the maximum pressure attained within the cylinder?
• What does "Full Throttle Height" refer to?
• What is the function of the discharge nozzle in a fuel injected engine?
• What could be a potential cause of an engine backfiring?
• What is the primary task of lubrication in an engine?
• The ignition switch is fitted in which circuit?
• What is a typical air/fuel ratio for normal engine operation?
• What occurs within the compressor of a turbo-charger?
• What would be the likely effect of prolonged running with a weak mixture?
• An exhaust gas temperature gauge is powered by:
• What affects the power output of an internal combustion engine?
• Maintaining a constant manifold pressure in a turbo-charged engine during the climb will cause:
• If the Starter Engaged Light remains on after engine start, what action should be taken?
• Which of the following is true regarding the operation of a supercharger?
• Why is tetra ethyl lead added to some aviation fuel?
• What controls the boost pressure of a turbo-charged engine?
• Immediately after an engine has started up, what is the first instrument reading to be checked?
• During take-off from a sea-level airfield, where is the waste gate positioned in a turbo-charged engine?
• If Rated Boost is selected but the R.P.M. is less than rated, what will be the effect on the Full Throttle Height?
• Engine oil pressure typically behaves how at low versus high RPM?
• Which of the following is an implication of the octane rating notation "100/130"?
• When the spark ignites the mixture in an engine, what occurs?
• What is the Beta range of a propeller?
• What does Indicated Mean Effective Pressure (IMEP) refer to in an engine?
• During which engine stroke does the combustion process occur in a fuel injected engine?
• Which system is often employed in turbocharged engines to maintain desired power levels?
• Why is a propeller blade twisted along its length?
• What occurs to the pitch of a variable pitch propeller to maintain constant rpm when IAS is increased?
• What check needs to be performed before starting a piston aero engine after ensuring the ignition is "OFF"?
• Pre-ignition refers to the condition when:
• If, during a "Mag. drop" check there is no drop in RPM, what is the most likely cause?
• What does the rotational speed of a turbo-charger depend on?
• What factors determine the angle of attack of a fixed pitch propeller?
• Which statement about exhaust valves is correct?
• In a supercharger, how does the mixture move through the system?
• How does the compressor output of a turbo-charger unit relate to manifold pressure?
• With a constant manifold pressure set during a climb, the power output from a supercharged engine:
• What does the engine-driven fuel pump supply?
• What is defined as the maximum altitude at which Rated Boost can be maintained with a specific R.P.M. set?
• What is the correct air/fuel ratio for an engine running at idle?
• What is the term for the ratio of power produced by an engine to the power available in the fuel?
• What causes propeller torque in an aircraft?
• In terms of maintenance, why is it important to check oil levels frequently in a piston engine?
• The colour of 100 / 130 grade low lead fuel is:
• When the Constant Speed Unit (CSU) is running "on speed", what is balanced?
• What effect does oil temperature have on engine performance?
• Which mixture type is less likely to cause detonation in the engine?
• How many revolutions are required to complete the induction and compression strokes in a six-cylinder four-stroke engine?
• In an inline four-cylinder aircraft engine, what is true about the crankshaft?
• What is the most efficient method for cooling a piston engine?
• What happens to the pitch of a propeller when power is increased?
• What is the main benefit of using a turbo-supercharger instead of a naturally aspirated engine?
• What is the purpose of a crankcase breather?
• When comparing short bursts of power from a turbocharged engine to that of a supercharged engine, what can be observed?
• If over-priming causes a fire to start in the engine's carburettor during starting, what is the best immediate action?
• What is the main purpose of the crankcase breather?
• What effect does excessive valve clearance have on valve operation?
• An air/fuel ratio of 9:1 would be considered:
• Why do propellers have an 'avoid' range of rpm?
• What material are piston rings commonly made from?
• What is present in the intake of a fuel injected engine?
• What is the relationship between propeller blade angle and efficiency during a climb?
• How are the turbine and compressor of a turbo-charger connected within its construction?
• If the waste gate of a turbo-charged engine seizes during the climb, what will happen to the manifold pressure?
• If an engine is fitted with a fuel injection system, what is true about the need for priming?
• If, during a "Mag. drop" check the engine cuts, what action must be taken?
• How is "Boost pressure" defined?
• With an increase of compressor discharge pressure, what happens to the fuel flow?
• What is the role of a throttle valve in a fuel injected engine?
• What could excessive tappet clearance indicate in an engine?
• How does a turbo-charged engine respond to rapid throttle opening compared to a normally aspirated engine?
• What device is used to measure temperature on a piston engine?
• What is the primary function of a diffuser in a carburettor?
• For an aircraft with a right-hand propeller, what effect will slipstream rotation acting on the fin have?
• What is the correct way to shut down an engine?
• What happens to the EGT and cylinder head temperature when the mixture is weakened?
• What provides the motive force to drive a turbocharger?
• Why is it considered dangerous to pump the throttle lever when starting an engine?
• What is a primary consideration for a fuel injected engine's discharge nozzle design?
• What is a consequence of excessive valve clearance in an engine?
• To maintain a constant boost pressure with increasing altitude, what action does the A.B.C. take?
• Detonation is likely to occur in the cylinders:
• When is the blade angle of a fixed pitch propeller set for optimum performance?
• Where does the greatest stress on a rotating propeller occur?
• From Top Dead Centre (TDC) to Bottom Dead Centre (BDC) on the practical power stroke, what happens to the temperature of the gases?
• What is the chemically correct mixture ratio for fuel to air?
• Valve lead occurs when which of the following happens?
• At what speed does the camshaft of a horizontally opposed four-stroke engine rotate?
• When does the spark appear at the plug electrodes?
• What is the gyroscopic effect of a right-hand propeller?
• What is true regarding the blade angle along the length of the propeller blade?
• What happens to propeller efficiency at maximum speed?
• What happens when the ignition switch is placed in the 'ON' position?
• What could cause an overly rich mixture during slow running?
• What effect does a right-hand propeller have when the engine is running regarding gyroscopic moments?
• Which component plays a critical role in preventing turbocharger failure due to excess pressure?
• "Static Boost" is the manifold pressure indicated on the boost pressure gauge when:
• During the induction stroke, what happens to the temperature of the gases?
• What happens to the temperature of gases within a four-stroke engine cylinder during the power stroke?
• Which of the following statements is incorrect about using a weak mixture?
• What is used to maintain the correct air/fuel ratio while climbing to higher altitudes?
• Boost pressure is primarily indicated on which gauge?
• The temperature measuring device in a four-cylinder in-line engine is typically fitted to which cylinder?
• In a normally aspirated engine, what happens to exhaust back pressure as an aircraft climbs?
• What is the function of a special starting battery in an impulse starter system?
• What characterizes a normally aspirated engine?
• What does a Manifold Pressure Gauge measure in a supercharged engine?
• What does insufficient tappet clearance at the inlet valve cause?
• What is the Compression Ratio of a four cylinder engine with a total volume of 9600cc, bore area of 100 cm² and a crank throw of 10 cm?
• The limit of the amount of supercharging that an engine can tolerate is reached when:
• How can the power output of an internal combustion engine be increased?
• In a "wet sump" oil system, where is the oil contained?
• What effect does increasing Indicated Airspeed (IAS) have on a variable pitch propeller?
• How can the compression ratio of an engine be defined?
• When is the mixture supplied by the carburettor considered weak?
• At idle or low power conditions, the turbo-charger waste gate is typically:
• When is "Static Boost" noted?
• What are the symptoms of an excessively rich mixture?
• What is the main purpose of an ignition switch?
• What is the maximum thermal efficiency of a typical piston engine?
• What does the constant speed propeller system primarily regulate?
• Where is a reduction gear fitted in an engine setup?
• What is the primary function of the oil filter in an engine?
• Because of the reduction in the density of the atmosphere associated with an increase in altitude:
• What does Maximum Continuous Power (M.C.P.) refer to?
• What is the purpose of an impulse starter in an engine?
• What happens to fuel flow with an increase in compressor discharge pressure?
• What happens to the pressure in the induction manifold of a normally aspirated engine as the throttle is opened?
• An 'Auto - Feathering' system primarily senses which condition?
• In a four-stroke engine, combustion theoretically occurs at which condition?
• In a fuel injected system, fuel is injected into the manifold when?
• What is Static Boost?
• What are the symptoms of carburettor icing when cruising in a fixed-pitch propeller equipped aircraft?
• When is the "Reference RPM" of an engine established?
• What defines volumetric efficiency in relation to an engine cylinder?
• What is the effect of a greater weight of combustible mixture in the cylinders?
• Which lubrication method is typically more complicated but effective in performance?
• What is the optimal condition for a fixed pitch propeller during cruise?
• Which method is effective in improving volumetric efficiency?
• What occurs in a convergent duct?
• Specific Fuel Consumption (S.F.C.) can be defined as?
• What is the preferred direction for aircraft parking prior to start-up?
• What is a potential consequence of not using an intercooler with a supercharger?
• In terms of thermal efficiency, what effect does leaning the mixture have?
• In a piston engine dry sump oil system, where are the oil temperature and pressure sensed?
• The primary purpose of using a "T" tail in aircraft design is to what?
• How many revolutions of the crankshaft are required to complete a full cycle in a four-stroke engine?
• During take off, what is the state of a fixed pitch propeller's angle?
• What is the primary benefit of using cast iron for piston rings?
• What characteristic does the scavenge pump system have in a lubrication system?
• What factor determines a turbo-charger’s rotational speed?
• How does propeller efficiency change for an aircraft with a fixed pitch propeller?
• During the compression stroke, which statement is true?
• To prevent large acceleration loads on the compressor and the drive shaft of an internal supercharger, it is usual to:
• Why is there extra space in the oil tank?
• What is the order of the correct working cycle of a four-stroke engine?
• In which scenario would a high-performance supercharger typically require the use of an intercooler?
• What type of energy conversion occurs when the air or mixture passes through the diffuser shroud?
• Where is the waste gate of a turbo-supercharger typically fitted?
• At takeoff, how should cowl flaps be selected?
• A weak mixture is typically used during which phase of flight?
• For maximum endurance the mixture control should be set to:
• What happens to the valve gear when the engine warms up, which tappet clearance accommodates?
• What is the effect of altitude on the boost pressure of an engine with an internal supercharger?
• Which statement is true about engines equipped with fuel injection?
• If the vent pipe of an aircraft's fuel tank becomes blocked, it will cause:
• Which component of the engine is primarily affected by thermal expansion during operation?
• What is necessary to obtain a spark across the gap between two electrodes?
• What is the main danger from using a weak mixture at a high power setting?
• What function does a hydraulic accumulator serve in a single acting propeller?
• What defines the term "Rated Boost" in relation to engine performance?
• What is the primary difference between AVGAS 100 and AVGAS 100LL?
• If an engine has a total volume of 2,100 cm3 and a swept volume of 1,800 cm3, what is its compression ratio?
• Why is it important for a waste gate to function properly in a turbo-supercharger?
• Which type of fuel is commonly used in a turbo-charged engine?
• To maintain the Rated Boost of a supercharged engine while reducing the R.P.M., what must be done to the throttle valve?
• How is the speed of the turbine in a turbo-charger controlled?
• The rotational speed of the turbo-charger of an engine which is at full throttle at low altitude is:
• What is the function of hydraulic valve tappets in some engines?
• Which mixture theoretically produces the maximum RPM?
• What does increasing the pressure in a supercharger system typically do to engine power output?
• The turbo-charger waste gate is spring loaded towards which position?
• What is the alpha range of a variable pitch propeller?
• What is mainly a disadvantage of using a turbocharger in an engine?
• What is the main function of a supercharger?
• What defines the geometric pitch of a propeller?
• What is the role of the oil scavenge pump in a lubrication system?
• What does the calorific value of a fuel refer to?
• What could result from a fuel supply that is excessively rich?
• What does the fuel priming pump supply fuel directly to?
• Which indicator would suggest a weak mixture?
• What is a correct statement regarding a rich mixture?
• If the waste gate of a turbo-charged engine seizes in the climb before critical altitude has been reached, what happens?
• What is the main purpose of the oil pump in the CSU?
• What is Valve Overlap?
• What increases the thermal efficiency of a piston engine?
• The presence of an engine driven fuel pump ensures what?
• What causes an increase in rev/min during the take off run at full throttle in a fixed pitch propeller?
• What does the Fuel Manifold Valve do?
• What is one method to prime a fuel injected engine?
• If the octane rating of a fuel is given as 100/130, what does it signify?
• How does the compressor output pressure of an internal supercharger compare to the manifold pressure?
• What does excessive blue smoke from the exhaust typically indicate?
• What happens to boost pressure as an aircraft climbs in altitude?
• What effect does a weak mixture have on engine performance?
• With the power lever opened for take off power at sea level, the throttle butterfly of an engine fitted with an internal supercharger would be:
• What effect does valve overlap have on the cylinder pressure?
• What could be a cause for the pressure relief valve to stick?
• Which factor can affect the performance of the engine-driven fuel pump?
• During cruising, which type of mixture is generally preferred?
• When is the pitch of a propeller most likely to be changed?
• In an internal combustion engine, detonation is caused by:
• Where is tappet clearance measured in an engine?
• How does increasing airspeed affect the propeller angle of attack?
• The distributor directs voltage from which winding to the spark plug?
• What is the purpose of the centrifugal feathering latch on a single acting propeller?
• What type of compression method is typically used for turbo-chargers and superchargers?
• What is the function of a diffuser in a supercharger?
• What problem is primarily prevented by the correct running down procedure?
• What direction does a right hand propeller rotate when viewed from the rear?
• The compression ratio has a significant effect on which aspect of engine performance?
• What is the purpose of fitting two valve springs to each valve?
• What is the main function of the propeller pitch change mechanism?
• If the specific gravity of a fuel is 0.7, how much will 100 Imperial Gallons of it weigh?
• Which cylinder in a four-cylinder inline air-cooled engine is the coolest while running?
• When is the engine checked for dead cut?
• What component operates the waste gate of a turbo-supercharger?
• Which type of compressor is typically used in a supercharger?
• As rotational speed increases in a four-stroke engine, what happens to the valve overlap?
• What is the purpose of the turbo-charger's bearing lubrication system?
• What does the Venturi in the carburettor choke tube create?
• What happens to a propeller that is windmilling?
• In a divergent duct, what happens to the velocity and pressure?
• Where is the waste gate located in a turbo-charged engine?
• What is the primary purpose of an intercooler in an engine system?
• What is the primary purpose of an accelerator pump?
• Where may an intercooler be placed in a high-performance supercharger setup?
• What key feature distinguishes AVGAS 100LL from AVGAS 100?
• What is one immediate effect of using a turbocharger on engine performance?
• What is the purpose of a condenser fitted in a magneto?
• What happens to the inlet manifold pressure of a turbo-charged engine during a climb?
• Which consequence is most likely from a malfunctioning carburetor?
• How is the swept volume of a cylinder calculated?
• How does air enter the compressor of a turbo-supercharger?
• The automatic boost pressure control capsules are made sensitive to which factor?
• How does a turbo-charger affect exhaust back pressure on an engine?
• What is the primary purpose of a supercharger?
• What is a common issue in engines that hydraulic tappets help to reduce?
• An internal supercharger is one which:
• What is the firing interval of a six cylinder horizontally opposed engine?
• What defines propeller torque?
• The waste gate on a turbo-charger regulates the quantity of:
• What can be a consequence of excessive combustion temperatures and pressures?
• Brake Horsepower is best described as?
• When an engine starts up and the starter key is released, to what position does the key return?
• What is the purpose of a valve spring?
• How many degrees of rotation are needed to complete a full cycle on a nine cylinder engine?
• What is a common method for priming an engine not equipped with a priming pump?
• The power increase that occurs with initial increase in altitude when an engine has an internal supercharger is due to what?
• How does the Fuel Control Unit determine the amount of fuel to discharge?
• The Fuel Control Unit is responsible for which of the following?
• What are the main reasons to exercise a propeller from fine to coarse pitch after warm-up?
• How can the effect of slipstream rotation on a single-engine aircraft be countered?
• The blade angle of a propeller is defined as the angle between which two components?
• The discharge nozzles in a fuel injected engine are designed to match which factor?
• The octane rating of a fuel is determined by comparing it with which substances?
• Over boosting an engine fitted with a turbo-charger is prevented by the installation of:
• What causes excessive cylinder head temperatures?
• To increase the rpm of a variable pitch propeller without moving the power lever, how must the propeller lever be adjusted?
• When adjusting the mixture to be richer, what is a potential consequence?
• What feature allows a variable pitch propeller to operate in the reverse mode?
• What is the purpose of valve lead in an engine?
• What is the effect of a blocked float chamber on engine performance?
• At what mixture and carburettor heat setting is a take-off normally carried out?
• What is the nature of the mixture control in an engine with fuel injection?
• When should the oil contents of a piston engine (wet sump) be checked?
• What is the maximum engine Brake Horse Power permitted for continuous safe operation called?
• Where should a fuel strainer be fitted in an engine?
• When does the turbo-charger waste gate fully open?
• In a climb with reduced IAS and increased rev/min, what happens to the angle of attack of a fixed pitch propeller?
• Superchargers are utilized to overcome which issue related to altitude?
• In a double banked radial engine, which statement is correct?
• What is the primary reason for having different pitch settings in a propeller?
• How does the use of a turbocharger benefit an engine?
• What lubricates and cools the turbo-charger bearing?
• "Flame Rate" is the term used to describe the speed at which:
• Why is the engine temperature monitored carefully when climbing?
• What is the role of an Automatic Boost Control Unit?
• What is the purpose of incorporating valve overlap in the valve timing of a piston engine?
• What is the primary purpose of supplying a rich mixture to the cylinders during takeoff and climb?
• What is a potential consequence of prolonged use of low R.P.M. in an engine?
• What filters the oil returning to the oil tank?
• How is the length of the stroke in an engine determined?
• What effect does the thrust force of a propeller have on the propeller tips?