The Gas Turbine Engine Part 3

Question 1

Pressure:

The air entering the compressor is usually at a pressure -

This negative pressure can be overcome as the aircraft gathers -

Answer 1

less than ambient

speed because of the ram effect

Question 2

Pressure:

From the entrance to the compressor there is a steady

The rate of increase accelerating in the -

Answer 2

rise of pressure through the successive compressor stages

later stages of compression

Question 3

After the air has passed all the compressor stages, a final rise in pressure occurs in the divergent -

Answer 3

flow of the diffuser

Question 4

The type of exhaust nozzle that keeps airflow supsonic?

Answer 4

Chocked type

Question 5

To problem of excessive gas temperature is overcome by -

Answer 5

diverting part of the compressor flow around the inner core of the combustion chamber.

Question 6

During the jet engine’s various stages, at what point will the first considerable reduction in velocity occur?

Answer 6

At the diffuser

Question 7

During the jet engine’s various stages, the beginning of the increase in velocity occur?

Answer 7

in the combustion chamber

Question 8

The greatest increase in velocity will occur?

Answer 8

At the nozzle

Question 9

During the jet engine’s various stages, a final rise in pressure will occur?

Answer 9

in the divergent flow of the diffuser

Question 10

which type of reverse?

These are primarily used on small corporate or business jets. During flight the doors, which resemble two halves of a bottomless bucket, form part of the rear of the exhaust pipe. When extended, usually hydraulically, the doors extend into the exhaust stream and deflect the flow forward

Answer 10

External door or bucket reversers

Question 11

which type of reverse?

This system is operated pneumatically. During flight the doors cover cascade vanes, but when operated the doors block the normal exhaust gas exit and deflect the flow through the vanes in a forward direction, which opposes the aeroplane’s forward motion.

Answer 11

Clamshell doors

Question 12

which type of reverse?

This type is only used on high bypass turbo-fan engines.

Answer 12

Cold stream blocker doors

Question 13

Smaller gas turbine engines use what type of starter?

Answer 13

Electric motor starter

Question 14

To to accommodate for the load requires of starting a turbine, the battery type most turbine powered aeroplanes have is?

Answer 14

Nicad batteries

Question 15

The type of starter that utilises a series wound field and a shunt wound field, used on light turbine engines?

Answer 15

Starter generator

Question 16

The type of started that make use of an APU or a ground unit, used with large transport aeroplanes, requiring a large supply of high pressure air?

Answer 16

Air turbine starter

Question 17

state the start malfunction:

Symptom:

Excessive EGT or other turbine temperature measurement

Cause:

Primarily because there is too much fuel and not enough air

Action:

Close start lever between 100 to 150 degrees before the temperature limit is reached to cut the flow of fuel. Possibly keep motoring the engine for cooling purposes, otherwise release start switches

Answer 17

Hot start

Question 18

state the start malfunction:

Symptom:

The engine turn but fails to light up even though there is fuel flow

Cause:

A defective ignition system, or igniter plug

Action:

Close start level and ignition switch, but continue to turn engine for either the stipulated time or indication from ground staff that no more fuel is coming out. Then either try a further start or release switches according to indications

Answer 18

Wet start

Question 19

state the start malfunction:

Symptom:

The engine lights up but does not accelerate to full idling RPM, higher than normal EGT for the low RPM

Cause:

Most likely a result of a starter motor problem: insufficient electrical power, low air pressure, premature starter disengagement. Also failure in one of the fuel system components

Action:

Abandon the start procedure

Answer 19

Hung start

Question 20

Action to be taken if there is an intake fire but no fire warning, during start.

Answer 20

Continue start to consume fire for a very short while. If the fire indication continues at all close the start lever but continue turning engine to blow fire out. If fire continues stop the engine to allow access to cowling for fire crew

Question 21

Action to be taken if a fire warning is experienced during start.

Answer 21

Abort start, closing start lever and releasing switches.

Question 22

A turbine lubrication system is similar to that of a -

Answer 22

dry sump system

Question 23

Which type of oil system:

The engine drives the oil pressure pump, so that as the engine speed increases so too does the pump speed and the oil pressure until, at a preset value, the relief valve opens to return excess oil to either the main supply tank or to the pressure pump inlet. This ensures that a constant oil pressure is maintained.

Answer 23

Pressure relief valve system

Question 24

Which type of oil system:

In this case the required oil flow rate are achieved by the size and speed of the pressure pump and the size of the oil delivery jets. The size, and thus the output, of the pressure pump is determined by the oil requirements of the engine operating at maximum speed. In order to prevent damage to filters or coolers from high pressure oil, pressure limiting valves are incorporated to by-pass these units.

Answer 24

Full flow system

Question 25

The component that is used to direct oil under pressure onto various components inside the engine, is -

Answer 25

Small oil jets

Question 26

The accessory drive gearbox contains two sections.

One for -

And the other for -

Answer 26

low power accessories

High power accessories