Block III (1b Engine Components), Block III (1c Utility Systems)

What is mounted to the accessory box and provides the initial rotation of the gearbox and compressor to start the engine?

Starter

What two types of starters are used on aircraft?

Pneumatic (air starter) and Mechanical (Jet Fuel Starter 'JFS')

What source can an engine use to pneumatically (air) start?

A. Auxiliary Power Unit (APU)

B. Bleed air from another engine

C. Aerospace Ground Equipment

D. All of the Above

D. All of the Above

What is a Jet Fuel Starter (JFS)?

A mechanical way of starting an aircraft, mostly used on fighters. It is a small internally mounted turbine engine that mechanically turns the compressor of the main engine to start the aircraft.

What does the Ignition/ Exciter Unit do?

Supplies high voltage to igniter plugs

What do igniter plugs do?

Send an electrical charge (spark) across a gap between two pieces of metal so the air/ fuel mixture is ignited

Name the five components in the engine fuel system.

(1) Engine driven fuel pumps

(2) Fuel Control Unit

(3) Fuel Manifold

(4) Fuel Nozzles

(5) Fuel Flow Indicator

What do the engine driven fuel pumps do?

Deliver pressurized fuel to a fuel control unit.

*Always sending as much as possible, is not controlled/ throttled

What does the fuel control unit do?

Controls and regulates amount of fuel based on the throttle position

What does the fuel manifold do?

Collects and distributes fuel flow from fuel control unit to fuel nozzles

(Plumbing/ piping around the outside of the engine)

What do the fuel nozzles do?

Spray/ inject fuel into the combustion area in a highly atomized, precise pattern of spray. Located in the combustion section/ chamber.

What does the fuel flow indicator do?

Indicates fuel flow in pounds per hour to the engine and sends information to a gauge in the cockpit.

What does the engine control system do?

Has throttle levers that provide engine control/ thrust output. Connected via mechanical cables or electronic signals to the engine.

What does an instrument system do?

Instruments (gauges) monitor critical engine operating conditions and normal/ abnormal operating ranges

What four types of instruments did we learn about?

(1) Tachometer

(2) Exhaust Gas Temperature/ Turbine Inlet Temperature

(3) Oil Pressure

(4) Oil Temperature

What does a tachometer do?

Indicates engine power output in PERCENTAGE of engines max RPM

What does an exhaust gas temperature/ turbine inlet temperature instrument do?

Uses thermocouples (temperature sensors) mounted around the engine to indicate the temperature (CELSIUS) of gases in exhaust or turbine inlet section

What does an oil pressure indicator do?

Indicates oil pressure in pounds per square inch (PSI)

What does an oil temperature indicator do?

Indicates temperature of oil

What do thrust reverses do?

Reverse the thrust from rearward to forward. Help slow the aircraft during landing roll or aborted take-offs. Reduces stress on landing gear/ brakes. Only high bypass engines have them.

How does a thrust reverser work?

The throttle position controls actuators which move mechanical doors. Mechanical doors close behind the exhaust section forcing the air forward instead of rearward.

What does a compressor anti-stall system do?

Prevents a compressor stall or surge.

During rapid acceleration or deceleration airflow can be disrupted in the compressor section and cause a build-up of pressure which leads to engine failure.

What are variable inlet guide vanes?

Normally located in the front before the first stage of compression. The angle of vanes directs airflow into the compressor section at the optimal engine performance rate. Helps avoid stalls. Found on Turbofan Engines.

What are variable stator vanes?

Positioned after rotor blades. The angle is changed to allow optimal engine efficiency of the compressor at all engine speeds.

What is the engine anti-ice system?

Uses hot compressor bleed air to prevent formation of ice on fan/ inlet section in front of the compressor section.

What does engine oil do?

Lubricates, cleans and cools bearings and gears

What is a wet sump oil system?

Stores oil in accessory gear box

What is a dry sump oil system?

Stores oil in externally mounted reservoir/ tank.

Utilizes scavenge pump

What is a scavenge pump?

Collects and returns oil to reservoir/ tank for reuse

What happens when an oil filter is blocked/ dirty?

An internal bypass valve is opened to allow oil to bypass the filter regardless of contaminants

What is a differential pressure pin (Delta-P) used for?

A red indicator pin extends to indicate a contaminated/ clogged filter

How does engine oil get cooled?

An oil cooler passes oil near streams of ram air or fuel. The heat energy is transferred from the oil to the air or fuel, and the oil exits the cooler at a lower temperature

What is the purpose of a pressure/ breather vent?

When oil heats up in the bearing cases, vapors are created. The vent system removes oil vapors by venting bearing compartments, oil tanks, and accessory gearboxes

How/ when do you service the oil system on an aircraft?

Oil levels are checked after each flight and serviced IAW Technical Order.

If oil levels are low, use either unopened cans poured into a filler neck (unpressurized), or use a service cart connected to an oil connection port (pressurized)

What are five safety precautions when servicing the oil on an aircraft?

(1) Wear PPE

(2) Operating temps can cause burns

(3) Oil is toxic, can cause fetal hazards (consult SDS)

(4) Wash if skin contact occurs

(5) Seek medical attention if ingested

What component rotates the gearbox and compressor on engine start?

A. Crank

B. Starter

C. Ignition

D. Flywheel

B. Starter

Which component contains the gap necessary for a spark to ignite the fuel/air mixture?

A. Ignition unit

B. Igniter plugs

C. Igniter gapper

D. Igniter exciter

B. Igniter Plugs

What unit of measure is used for a fuel flow indicator?

A. Pound per square inch

B. Gallons per hour

C. Miles per gallon

D. Pounds per hour

D. Pounds per hour

What component in the fuel system controls and regulates fuel based on throttle position and engine condition?

A. Fuel pump

B. Fuel nozzles

C. Fuel control unit

D. Fuel manifold tubing

C. Fuel control unit

How is oil pressure measured?

A. Pounds per hour

B. Degrees of Celsius

C. Pounds per square inch

D. Revolutions per minute

C. pounds per square inch

What does the engine tachometer indicate?

A. Power output in percentage of RPM rating

B. Power output in pound per square inch

C. Power input to engine inlet intake

D. Pounds of thrust

A. Power output in percentage of RPM rating

What are mechanical doors that redirect engine thrust forward?

A. Exhaust closer

B. Thrust forward

C. Thrust reversers

D. Exhaust reversers

C. Thrust reversers

What maintains efficiency of the compressor at all engine speeds?

A. Variable stator vanes

B. Engine anti-ice system

C. Variable inlet guide vanes

D. Compressor anti-stall system

A. Variable stator vanes

What uses engine bleed air to prevent the formation of ice on fan/inlet section?

A. Engine anti-ice system

B. Aircraft air conditioning

C. Engine inlet heater probe system

D. Engine intake Rapid Air Movement (RAM) system

A. Engine anti-ice system

What stores oil for oil system use?

A. Oil pump

B. Reservoir/tank

C. Oil compressor

D. Breather/release valve

B. Reservoir/ tank

Which type of pump returns oil from the engine back to a reservoir/tank?

A. Dry

B. Pressure

C. Scavenge

D. Backflow

C. Scavenge

Which valve opens to allow oil to bypass a blocked/dirty filter element?

A. Bypass

B. Pressure

C. Oil cooler

D. Red indicator

A. Bypass

What is the purpose of the oil pressure/breather vent?

A. Relieve excess pressure in the system

B. Return oil to reservoir/tank in wet sumps

C. Provide bypassed oil to return to dry sumps

D. Remove oil vapors from bearing compartments and accessory gearbox

D. Remove oil vapors from bearing compartments and accessory gearbox

What is required if oil is ingested?

A. Notify Commander

B. Seek medical attention

C. Allow sufficient time for oil to air dry

D. Leave clothing on to prevent further contamination

B. Seek medical attention

What hazard is present by the oil operating temperatures?

A. Rash

B. Burns

C. Irritation

D. Excessive dryness

B. Burns

What is the Bleed Air System?

A source of high temperature (900°F), high volume, low pressure air. It comes from the compressor section of the engine and is used for various aircraft pneumatic systems.

What can Bleed Air be used for?

(1) Cabin pressurization, heating, and cooling

(2) Deicing and anti-icing equipment

(3) Pneumatic starting of engines

What is used to route air from engine compressor, APU, or external air source (Ground Equipment) to aircraft systems?

Bleed Air Ducts

What isolates the engine from the bleed air system and provides a means to control bleed air flow into or out of the engine?

Engine Bleed Air Shut-Off Valves

What controls bleed air pressure to keep it within established tolerances (regulates)?

Bleed Air Pressure Regulator

What type of valve allows air flow in one direction only?

Check Valves

What provides a connection point for an external air source?

External Air Receptacle

What is a small turbine compressor that can provide bleed air for engine starting?

APU (Auxiliary Power Unit)

What provides conditioned bleed air for crew and passenger comfort, equipment cooling, and aircraft pressurization?

Air Conditioning System

What are the six components of the Air Conditioning System?

(1) Heat Exchanger

(2) Cooling Turbine

(3) Water Separator

(4) Modulating/ Temperature Mixing Valve

(5) Temperature Selector/ Controller

(6) Air Ducts

What does the Heat Exchanger in an A/C System do?

Utilizes RAM air to initially cool bleed air

What does the Cooling Turbine do in an A/C System?

Cools bleed air to near freezing temperatures by rapid expansion

What does the Water Separator do in an A/C System?

Removes excess moisture from cooled air after air travels through cooling turbine

What does the Modulating/ Temperature Mixing Valve do in an A/C System?

Mixes untreated hot bleed air with conditioned cold air to obtain desired cabin temperature

What does a Temperature Selector/ Controller do in an A/C System?

Controls the position of the temperature mixing valve to maintain constant desired temperature

What does the Pressurization System do?

Pressurizes aircraft cabin to simulate at or near sea-level to ensure crew comfort and adequate amount of oxygen is available for breathing at higher altitudes

Where does the pressurization system get it's source of pressurized air?

Air Conditioning System (after it has been mixed)

True or False:

The Pressurization System operates automatically when pressure differential exists inside and outside the aircraft

True

What are the three components of the Pressurization System?

(1) Cabin Pressure Regulator

(2) Outflow Valve

(3) RAM Air Valve

What provides the means of selecting desired cabin pressure altitude and pneumatically adjusts the position of outflow valves to maintain desired cabin pressure?

Cabin Pressure Regulator

What Allows the escape of pressurized air as needed, is pneumatically positioned by the cabin pressure regulator, and limits maximum cabin pressure?

Outflow Valve

What is used for emergency ventilation of pressurized compartments and works with the outflow valve to preserve necessary pressurization?

RAM Air Valve

What does the Oxygen System do?

Provides a source of oxygen at higher altitudes for crew or passengers

When would a pressurized aircraft oxygen system be used?

Under normal conditions (engine bleed air replicates pressure at a lower altitude) e.g. commercial jets or any section seating personnel

What three scenarios would a non pressurized aircraft oxygen system be used?

(1) During emergency from loss of cabin pressure

(2) High altitude cargo/ personnel airdrops

(3) Combat and aerial refueling operations

What (1) automatically supplies the proper mixture of cabin air and oxygen (based on aircraft's altitude) and

(2) regulates the flow of oxygen to aircrew oxygen masks?

Oxygen Regulator

What are the two ways to store oxygen on an aircraft?

Gaseous or Liquid (LOX) state

What is the name of the system that generates on-board oxygen?

On-Board Oxygen Generating System (OBOGS)

What are the two types of oxygen regulators?

Constant Flow and Diluter-Demand

Which type of oxygen regulator provides the same output pressure or flow regardless of altitude?

Constant Flow Rregulator (Most common on non-pressurized aircraft and portable oxygen systems)

Which type of oxygen regulator can provide 100% oxygen or "diluted" oxygen (mixed with cabin air) depending on the user selection?

Diluter-Demand Regulator

Which type of oxygen regulator can be set to "demand" so oxygen mixture flows into the mask during inhalation?

Diluter-Demand Regulator

What component of the LOX System stores oxygen in liquid state until needed by aircrew and converts it to gas prior to use?

Converter

Which component of the LOX System warms the gaseous oxygen prior to use?

Heat Exchanger

Which component of the LOX System indicates liters of LOX stored in converter?

Quantity Gauge

What unit is LOX (Liquid Oxygen) measured in?

Liters

What oxygen system allows aircrew to move around unpressurized aircraft for short periods (can be recharged from main oxygen system)?

Portable Oxygen Bottle/ Cylinder

Which oxygen system filters nitrogen and other impurities delivering breathable air high in oxygen content?

Molecular Sieve Oxygen Generation System (MSOGS)

Which oxygen system separates bleed air through a two-bed molecular sieve pressure swing adsorption (PSA) technology?

Molecular Sieve Oxygen Generation System (MSOGS)

What are the two components and their purpose of the Molecular Sieve Oxygen Generation System (MSOGS)?

Concentrator (produces continuous oxygen-rich gas) and Oxygen Monitor (senses the partial pressure of the gas and provides a low-pressure warning to the pilot)

Which oxygen system eliminates the need, on some aircraft, to store and transport liquid oxygen systems?

Molecular Sieve Oxygen Generation System (MSOGS)

Which type of fire detector is an electrical circuit that will close once a pre-set temperature is reached (placed in specific locations throughout engine compartment)?

Thermal Switches

Which type of fire detector is a wire embedded in an insulating core and will melt the insulation at a preset temperature completing the circuit to the warning light?

Continuous Loop

What does a red warning light on the pilot's instrument panel indicate?

Engine Fire

What does a yellow or flashing red warning light on the pilot's instrument panel indicate?

Engine Overheat

True or False:

Some aircraft are equipped with an audible fire warning device

True

What is located in the cockpit and is used to check warning lights and audio signals?

Test Switch

What is located in the cockpit and provides emergency fuel shut-off, contains engine fire warning lights, and arms fire extinguishing system on aircraft?

T-handles/ Fire/ Overheat Warning Panel

What extinguishes an external engine fire after pulling the fire T-handle, pushing fire push buttons, or activated by a toggle switch on the fire control panel?

Fire Suppression System

What is the non-toxic/ non corrosive liquid agent stored in a spherical container used in the fire suppression system?

Halon