Turbines Finals

Where is the fuel metering valve physically located?

The fuel pump assembly

The fuel control unit

The fuel flow divider

The P&D (pressurization & dump) valve

What is the power supply source for the electronic control unit of a FADEC fuel system when the engine is running?

A dedicated alternator (generator) on the accessory gearbox

The onside engine generator

The aircraft supplies power to the electronic control unit at all times.

The auxiliary power unit (APU)

What type of fuel nozzle is shown in the illustration?

Simplex

Duplex

Hybrid

Dual flow simplex

As per the diagram, where does unmetered fuel become metered fuel?

Main fuel shutoff valve (spar valve)

Fuel Control Unit (F.C.U.)

High pressure fuel pump

Low pressure fuel pump

When would the fuel system spar valve normally be closed by maintenance personnel?

Whenever there is an upstream fire or overheat, between the fuel tank(s) and the valve

During engine ground run-ups

During a wet cycle to check for fuel flow

When disconnecting a fuel line downstream from the valve

What is the purpose of the fuel heater shown in the diagram?

Cools 13th stage air prior to use for aircraft systems, such as air conditioning and pressurization

Removes contaminants from the fuel to prevent filter clogging

Cools the engine and CSD oil

Prevents the formation of ice crystals in the fuel

The pressurizing & dump valve schedules primary and secondary fuel flow to fuel nozzles. What is its other function?

Add air to the fuel nozzles for proper atomization in the combustion chamber

Boost the pressure from the engine-driven fuel pumps to ensure a positive fuel supply

Provide positive fuel cutoff at engine shutdown, draining fuel from the manifolds

Remove contaminants from the fuel system, prior to entering the combustion chamber

What is the purpose of the combustion chamber fuel drain valve?

Drains all the combustion chamber fuel back into the aircraft fuel tank after shutdown

Drains all excess fuel in the combustion chamber to another engine

Used to provide additional fuel to achieve takeoff power

Drains residual combustion chamber fuel after shutdown, to prevent a tailpipe fire or subsequent hot start

Which fuel system component is operated by the fire handle?

The engine-driven fuel pump assembly

The fuel flow divider

The spar valve

The fuel pressure regulating valve

Which engine system does NOT use compressor discharge air for its operation?

Active clearance control

Engine anti-ice

Generator cooling

Engine x-bleed (pneumatic) starting

What is the primary reason that ventilation air is provided in engine compartments?

Helps the engine breathe better

It's part of the active clearance control system used to reduce tip clearance between the compressor blades and engine casing.

Reduces the risk of compressor stall

Removes vapours that could potentially ignite

What is the purpose of the low and high pressure turbine active clearance control system?

Optimize tip clearance between the blades and the engine casing

Increase the tip clearance between the blades and engine casing

Help prevent the main engine shaft from warping

Lower the temperature in the turbine section, to increase the engine service life

What purpose is served by all the small holes found on engine turbine blades?

They reduce the weight of the blades.

They provide a means of cooling the blades.

They provide a means of allowing blade expansion to minimize tip clearance.

The holes are designed to reduce airflow disturbances around the blades.

Which air source provides cooling for the HP turbine blades and disks?

Fan discharge air

Low pressure turbine discharge air

High pressure compressor discharge air

Cabin air

How are the various nacelle cooling and ventilation areas identified on most engines?

Area

Zone

Station

Reference

What does the acronym 'S.O.A.P.' represent when sampling engine oil?

Spectrometric oil analysis program

Sample oil analysis process

Spectral oil acquisition process

Spectronic oil acquisition process

What is the purpose of the oil scupper?

Is used to filter the oil.

Is used to drain away oil while servicing to prevent a possible fire hazard.

It has a magnet to inspect the oil for ferrous metal contaminants.

It turns on a warning light in the Flight Deck to warn the pilot of oil contamination.

Select the answer that best describes a Dry Sump oil system

Is never used on large airliner engines

Dry sump system does not require an oil filter

All the oil is stored inside the engine

Has an external oil tank for oil storage

Under what ATA Chapter in the MM or IPC will the oil system be found?Under what ATA Chapter in the MM or IPC will the oil system be found?

What does ‘high viscosity’ mean when discussing engine oil systems?

The oil is designed for use at high altitudes.

The oil is very thin.

The oil has the same thickness as water.

The oil is very thick.

What type of engine oil system is illustrated in the diagram?

Dry sump

Wet sump

Positive flow

Negative flow

What is the primary purpose of conducting a 'S.O.A.P.' test on engine oil?

Checks the chemical stability of oil received from the manufacturer

Removes suspended particles from the oil in the system that the filter can't capture

Used to determine the oil viscosity at various temperatures

A process used to inspect the oil for metal particles

When is oil normally serviced on a typical turbine engine?

While the engine is operating (running)

Immediately after engine shutdown

5 to 30 minutes after engine shutdown

Greater than 2 hours after engine shutdown

Identify a common inspection item on a starter-generator.

Brush wear

Impeller condition

Start valve operation (located upstream from the starter)

Igniter plug condition

What action would normally be taken if an air turbine start valve failed to open during an engine start procedure?

The engine cannot be started and the start valve would need to be replaced.

The manual override on the engine start valve would be operated.

The engine would require hand-cranking at the accessory gearbox.

An alternate start valve would be used at the engine pylon.

You have just selected 'start' on a double-spool turbofan engine and confirmed that the start valve has opened. What is the first engine parameter that you would observe to confirm starter engagement?

N1 rotation

N2 rotation

Exhaust gas temperature (EGT)

Oil pressure rising

When would ignition cut out during an engine start?

Ignition shuts off when the starter cuts out.

At or near completion of engine start

Ignition stays on at all times to sustain combustion.

Only when it is manually selected off in the flight deck

What type of igniter plug is depicted in the accompanying picture?

Glow plug

Element igniter

High tension (high energy) igniter

Low tension (low energy) igniter

How is combustion sustained after an engine start is completed on most turbine engines?

Both igniters are selected on.

A single igniter remains energized.

Combustion is self-sustained, with both igniters selected to 'Off' or 'Auto.'

A single igniter pulses once every minute.

Where is the starter physically located on a turbine engine?

The fan case

The high pressure compressor case

The accessory gearbox

The internal gearbox

What unit of measure is most commonly displayed on fuel flow indicators?

Pounds per hour

Kilograms per minute

Cubic meters per hour

Cubic meters per minute

Which two metals commonly make up an exhaust gas temperature (EGT) thermocouple?

Chrome and aluminum

Chromel and alumel

Zinc and nickel

Silver and chromium

Which system is used as a performance indicator on a turboprop engine?

Engine pressure ratio (EPR)

Core engine speed (Ng)

Torque oil pressure

Free (power) turbine speed

Choose which of the following is NOT a common oil system parameter indicated in the flight deck?

Oil pressure

Oil temperature

Oil quantity

Oil flow

Turbines Finals

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