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The conditions to be met to activate a shunt generator are:

1. Presence of a permanent field; 4. Minimum rotation speed.

On a normally aspirated engine, the manifold pressure gauge always indicates:

A lower value than atmospheric pressure when the engine is running.

In the stator of a turbine, the gas velocity V and static pressure p vary as follows:

A turbine stator is a convergent duct. Pressure will decrease, velocity will increase.

An EGT (Exhaust Gas Temperature) indicator for a piston engine is used to:

Assist the pilot to set the correct mixture.

Exhaust gas temperature sensing is usually taken:

Between the gas generator turbine and the free power turbine.

At constant RPM with a normally aspirated engine and a fixed pitch propeller, as altitude increases, if the mixture is not leaned:

Both the density of air entering the carburettor and the fuel flow decrease.

On an aeroplane equipped with a constant speed propeller, the RPM indicator enables:

Control of the propeller regulator and the display of propeller RPM.

The purpose of the contact breaker is to:

Control the primary circuit of the magneto

The by-pass air in a turbo fan engine has the effect of a lower specific fuel consumption by causing an overall:

Decrease in average exhaust gas flow velocity and a higher mass flow.

The primary reason for a limitation being imposed on the temperature of gas flow in a gas turbine is to:

Ensure that the maximum acceptable temperature at the turbine blades is not exceeded.

If an engine fails to stop with the magneto switch in OFF position, the cause may be:

Excessive carbon formation in cylinder head.

Pulling the fire shutoff handle causes a number of devices to disconnect. In respect of the AC generator it can be said that the:

Exciter control relay and the generator breaker open.

The conditions which can cause detonation are:

High manifold pressure and low revolutions per minute.

Dual ignition provides a factor of reliability and:

Improves combustion efficiency.

The power output of a piston engine without supercharging increases with increasing altitude in standard atmosphere at constant Manifold Air Pressure (MAP) and RPM because of the:

Increase of the air density behind the throttle valve.

The function of a feed box in the fuel tank is to:

Increase the fuel level at the boost pump location

During a climb in a standard atmosphere with constant MAP and RPM indications and at a constant mixture setting, the power output of a piston engine:

Increases.

When changing power on engines equipped with a constant speed propeller, engine overboost is avoided by:

Increasing the RPM before increasing the manifold pressure.

In a free turbine engine, the energy delivered by the free turbine stages:

Is dependent on the rotational speed of the gas generator.

An abortive (hung) start is the term used to describe an attempt to start in which the engine:

Lights up, but fails to accelerate sufficiently.

The rotor blades of an axial compressor of a gas turbine engine are often mounted on a disk or drum using a 'loose fit' because this:

Limits damage to the blades due to vibration.

Engine ignition in continuous mode provides:

Low power ignition when there is a risk of flameout.

The primary input signals for a hydro-mechanical gas turbine engine fuel control system include:

N2, compressor discharge pressure, compressor inlet temp, fuel shut-off, thrust lever angle

The frequency of an AC generator is dependent on the:

Number of pairs of poles and the speed of the moving part. Frequency (Hz) = RPM x Number of pole pairs/60

Concerning a constant speed propeller of a twin engine aeroplane controlled by a single-acting pitch control unit:

Oil pressure turns the propeller blades towards a smaller pitch angle.

In flight, if the temperature of the constant speed drive (CSD) indicator is in the red arc the:

Pilot must disconnect it, and the generator is not available for the rest of flight.

The diffuser in a centrifugal compressor is a device in which the:

Pressure rises and velocity falls.

An impulse coupling is installed on a magneto of a piston engine to:

Provide a strong spark at top dead centre for engine starting.

Engine auxiliary gearboxes:

Provide the drives for a wide variety of services and may even provide for the support of the engine in the airframe.

In a gas turbine combustion chamber:

Secondary air is required for cooling of the inner casing.

The purpose of a distributor in an ignition system of a piston engine is to distribute:

Secondary current to the sparking plugs.

The type of windings commonly used in DC starter motors are:

Series wound.

Equation for thrust

T = m(Vj -Vv ) + A(pj - p0). m (vj - vv): the thrust caused by the acceleration of the air mass flow. A (pj -p0): the thrust caused by the pressure difference at the exhaust.

The function of a constant speed drive (CSD) is to ensure:

That the generator produces a constant frequency.

On landing and prior to shut down, a gas turbine engine should be run at "GROUND IDLE" for a short period. This allows:

The core temperature to diminish.

When applying carburettor heating:

The mixture becomes richer.

Pre-ignition refers to the condition that may arise when:

The mixture is ignited by abnormal conditions within the cylinder before** the spark occurs at the plug

One of the advantages of annular combustion chamber over a multiple can is that:

The thermal load distribution on the HP turbine is more favourable.

The purpose of gas turbine engine trending is:

To enhance maintenance planning and detect anomalies.

In the event of an engine failure during flight, the blades of a constant speed propeller in a single engine aeroplane not fitted with a feathering system tend to move:

Towards the smallest blade angle by centrifugal twisting moment and/or spring force.

In a gas turbine engine the creep phenomenon is the most severe in the:

Turbine rotors.

Engine temperature limitations of a gas turbine engine are usually imposed due to temperature limitations on the:

Turbine section.

The replenishment of an onboard oxygen bottle must be done:

With the engine(s) off.

An axial compressor, compared to a centrifugal compressor:

has a higher pressure ratio and the ability to compress a high mass of air.


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