15.10 Lubrication Systems (Level 1, 4 Questions)

Question 1

Where is oil stored in a wet sump lubrication system?
A) In an external tank
B) Within the engine
C) In the oil cooler

Answer 1

B) Within the engine

Question 2

What is a key feature of a dry sump lubrication system?
A) Oil is used only once and discarded
B) Oil is stored within the engine
C) Oil is stored in an external tank and recirculated

Answer 2

C) Oil is stored in an external tank and recirculated

Question 3

Why is oil pumped through a lubrication system?
A) To cool the fuel nozzles
B) To clean turbine blades
C) To maintain constant pressure

Answer 3

C) To maintain constant pressure

Question 4

What is a characteristic of a full-flow lubrication system?
A) Oil pressure is regulated regardless of conditions
B) Oil pressure varies with rotor speed and temperature
C) It maintains a constant oil pressure

Answer 4

B) Oil pressure varies with rotor speed and temperature

Question 5

What component prevents excessive pressure in a full-flow lubrication system?
A) Oil filter
B) Pressure regulating valve
C) Pressure relief valve

Answer 5

C) Pressure relief valve

Question 6

What is the main purpose of a pressure regulating valve in a constant pressure system?
A) To increase oil viscosity
B) To cool the oil
C) To maintain consistent oil pressure

Answer 6

C) To maintain consistent oil pressure

Question 7

What is one advantage of a full-flow lubrication system?
A) Requires regulation components
B) Maintains consistent oil pressure
C) Simple and low maintenance

Answer 7

C) Simple and low maintenance

Question 8

What is a disadvantage of a constant pressure lubrication system?
A) Inconsistent oil pressure
B) High oil pressure at high speeds
C) More complex and requires regulation components

Answer 8

C) More complex and requires regulation components

Question 9

Which is a disadvantage of a full-flow lubrication system?
A) Inconsistent oil flow
B) High oil pressure at high speeds
C) Low maintenance

Answer 9

B) High oil pressure at high speeds

Question 10

Which of the following is a main lubrication subsystem in an engine?
A) Ignition System
B) Scavenge System
C) Cooling System

Answer 10

B) Scavenge System

Question 11

What is the purpose of the oil reservoir and supply system?
A) To ignite the fuel-air mixture
B) To store and deliver oil to the engine
C) To vent excess exhaust gases

Answer 11

B) To store and deliver oil to the engine

Question 12

Which subsystem removes used oil from the engine?
A) Vent System
B) Scavenge System
C) Monitoring System

Answer 12

B) Scavenge System

Question 13

What component of the oil tank helps relieve pressure after engine shutdown?
A) Check valve
B) Vent system
C) Deaerator tray

Answer 13

B) Vent system

Question 14

Which of the following is a feature commonly found in an engine oil tank?
A) Fuel injector
B) Sight glass
C) Spark plug

Answer 14

B) Sight glass

Question 15

What material is typically used for engine oil tanks?
A) Titanium
B) Aluminium
C) Steel

Answer 15

B) Aluminium

Question 16

What is the primary method of oil cooling in the lubrication system?
A) Air-oil heat exchanger
B) Engine bearings
C) Fuel-cooled oil cooler

Answer 16

C) Fuel-cooled oil cooler

Question 17

Which component comes immediately after the pressure filter in the oil flow path?
A) Oil tank
B) Air-oil heat exchanger
C) Oil pump

Answer 17

B) Air-oil heat exchanger

Question 18

What is the function of the air-oil heat exchanger in the oil flow path?
A) Primary filtration
B) Additional cooling
C) Pressure regulation

Answer 18

B) Additional cooling

Question 19

Which type of oil pump uses inner and outer rotors?
A) Gear Pump
B) Gerotor Pump
C) Vane Pump

Answer 19

B) Gerotor Pump

Question 20

What is a common feature of gear pumps in lubrication systems?
A) Uses centrifugal force
B) Separate housings for each element
C) Multiple elements housed in a common casing

Answer 20

C) Multiple elements housed in a common casing

Question 21

Which type of oil pump is noted for being more compact and efficient?
A) Gear Pump
B) Screw Pump
C) Gerotor Pump

Answer 21

C) Gerotor Pump

Question 22

What is the purpose of the oil pressure regulating valve?
A) To cool the oil before it enters the bearings
B) To maintain oil pressure within system limits
C) To increase oil flow to the gearbox

Answer 22

B) To maintain oil pressure within system limits

Question 23

Which component in the oil pressure regulating valve provides the reference force?
A) Diaphragm
B) Piston
C) Spring

Answer 23

C) Spring

Question 24

How does the oil pressure regulating valve operate?
A) By opening fully when oil is cold
B) By balancing spring force against system pressure
C) By adjusting pump speed

Answer 24

B) By balancing spring force against system pressure

Question 25

What is the primary purpose of lubrication in an engine? A) To increase engine speed B) To cool bearings and gears C) To filter contaminants from fuel

Answer 25

B) To cool bearings and gears

Question 26

Which bearing in the engine requires intense cooling? A) Compressor bearing B) Exhaust turbine bearing C) Fuel pump bearing

Answer 26

B) Exhaust turbine bearing

Question 27

How can air-cooling assist in engine lubrication cooling? A) By increasing oil pressure B) By using bleed air to supplement oil cooling C) By reducing oil viscosity

Answer 27

B) By using bleed air to supplement oil cooling

Question 28

What component is commonly used as the restrictive element in most oil pressure regulators? A) Diaphragm B) Spring-loaded poppet valve C) Pressure adjusting screw

Answer 28

B) Spring-loaded poppet valve

Question 29

How does the oil pressure regulator control the oil pressure? A) By adjusting the oil temperature B) By balancing spring force and outlet pressure on a diaphragm C) By redirecting oil flow to the fuel system

Answer 29

B) By balancing spring force and outlet pressure on a diaphragm

Question 30

What is the main function of the oil pressure relief valve in some large turbofan engines? A) To regulate oil temperature B) To relieve excess pressure by bypassing oil back to the pump inlet C) To increase oil pressure during startup

Answer 30

B) To relieve excess pressure by bypassing oil back to the pump inlet

Question 31

What is the main purpose of a bypass valve in an engine lubrication system? A) To increase oil pressure during flight B) To regulate oil flow through the cooler or filter to maintain proper oil temperature or pressure C) To add fuel to the oil for lubrication

Answer 31

B) To regulate oil flow through the cooler or filter to maintain proper oil temperature or pressure

Question 32

A) It routes oil through the cooler immediately to cool the engine B) It opens to bypass the oil cooler when oil is cold and thick, helping the engine warm up quickly C) It shuts off oil flow to increase pressure

Answer 32

B) It opens to bypass the oil cooler when oil is cold and thick, helping the engine warm up quickly

Question 33

What happens if the oil cooler becomes blocked or clogged? A) The bypass valve opens to prevent oil cooler rupture by diverting oil flow around the cooler B) The oil pressure increases until the cooler unclogs C) The oil cooler shuts down automatically

Answer 33

A) The bypass valve opens to prevent oil cooler rupture by diverting oil flow around the cooler

Question 34

What is the primary function of an oil filter in an engine lubrication system? A) To cool the oil before it enters the engine B) To remove contaminants and protect the system C) To increase oil pressure during operation

Answer 34

B) To remove contaminants and protect the system

Question 35

Where are fuel-cooled oil coolers typically installed in the lubrication system? A) In the scavenge line (cold tank system) B) In the supply line (hot tank system) C) After the oil filter only

Answer 35

B) In the supply line (hot tank system)

Question 36

What is the role of the scavenge pump in an engine lubrication system? A) To pump fresh oil into the engine bearings B) To remove oil and contaminants from bearing compartments and gearboxes and return filtered oil to the tank C) To cool the oil using fuel or air

Answer 36

B) To remove oil and contaminants from bearing compartments and gearboxes and return filtered oil to the tank

Question 37

What is the main purpose of the lubrication system breather (vent) system? A) To cool the oil before it enters the bearings B) To remove excess air from bearing cavities and return it to the oil tank C) To increase oil pressure in the system

Answer 37

B) To remove excess air from bearing cavities and return it to the oil tank

Question 38

What does the deaerator do in the lubrication system breather system? A) Cools the oil before it reaches the bearings B) Separates air from oil vapor and vents the air overboard C) Pumps oil into the engine bearings

Answer 38

B) Separates air from oil vapor and vents the air overboard

Question 39

Why are check relief valves used in the vent system? A) To increase oil temperature for better flow B) To maintain a slight positive pressure (~4 psi) for the oil pump inlet C) To filter contaminants from the oil

Answer 39

B) To maintain a slight positive pressure (~4 psi) for the oil pump inlet

Question 40

What does a capacitance-type transmitter measure in the lubrication monitoring system? A) Oil temperature B) Oil pressure C) Oil level by detecting capacitance changes

Answer 40

C) Oil level by detecting capacitance changes

Question 41

How does a reed switch transmitter indicate oil level? A) By measuring electrical resistance changes in the oil B) By using a float and magnet to activate reed switches C) By detecting oil temperature variations

Answer 41

B) By using a float and magnet to activate reed switches

Question 42

Which of the following is NOT monitored by the lubrication system monitoring system? A) Oil quantity B) Oil condition C) Engine RPM

Answer 42

C) Engine RPM

Question 43

What is the primary purpose of magnetic chip detectors in the oil system? A) To measure oil temperature B) To catch metal particles attracted to magnets C) To filter out water contamination

Answer 43

B) To catch metal particles attracted to magnets

Question 44

How does the debris monitoring system detect oil contamination? A) By measuring the oil’s viscosity B) By detecting particle size, quantity, and type C) By monitoring oil pressure fluctuations

Answer 44

B) By detecting particle size, quantity, and type

Question 45

What happens to the resistance between magnets in a magnetic chip detector when metal particles collect? A) Resistance remains the same B) Resistance increases or decreases, signaling contamination C) Resistance causes the oil temperature to rise

Answer 45

B) Resistance increases or decreases, signaling contamination