1) When reheat is selected and in operation, the mass gas flow Report

decreases

increases

remains the same

2) Screech liners in the afterburning jet pipe Report

prevent unstable combustion

acts as noise suppressors

prevent cyclic vibrations of large amplitude

3) Water methanol for cooling is injected into the Report

engine hot zone

combustion chamber

compressor inlet or outlet

4) On an injection system Report

methanol is injected neat

town water/methanol is injected

demineralized water/methanol is injected

5) When using water methanol in an axial flow compressor, it is injected into the Report

intake

burner

compressor inlet or burner section

6) The main reason for adding methanol to the water is to Report

temper the cooling effect of the water to prevent distortion

supply the additional heat required

prevent mixture freezing

7) The primary purpose of water injection is to Report

decrease mass airflow

cool the turbine

increase the calorific value of the fuel

8) Water used in a thrust augmentation system should be demineralised to prevent Report

blocking the jet

carbon formation

fouling the blades and vanes

9) The quantity of water usually carried by an aircraft equipped with water injection is enough for Report

one take-off

two take-offs

three take-offs

10) Water methanol injection will increase thrust by up to Report

30%.

50%.

70%.

11) Injection of water/methanol into compressor inlet causes Report

increase in power due to the burning of methanol alone

increase in power without the need for burning extra fuel

increased efficiency of the engine due to reduced icing in the airflow

12) Reheat is the term used to describe Report

adding fuel in the exhaust section

adding of fuel in the turbine section

adding of fuel in the compressor section

13) Water/methanol is injected Report

at high temperatures

at high temperature, at high altitudes

at high temperatures or high altitudes

14) The reheat ignition system which incorporates a platinum/rhodium element is known as Report

catalytic ignition

spark ignition system

hot-shot ignition system

15) Water or water/methanol injected into the combustion chamber inlet increases Report

mass airflow through the turbine

fuel to air ratio by up to 20%.

combustion chamber outlet temperatures

16) Methanol is added to water when augmenting thrust in order to Report

reclaim lost pressure at the compressor

increase the density of air entering the compressor

reclaim lost heat at the turbines

17) Afterburning is initiated in order to Report

heat the exhaust to prevent choking at subsonic gas velocities

burn off the fuel that is not combusted in the combustion section

increase the local speed of sound at the jet nozzle

18) How is the flame stabilised in the reheat system of a gas turbine engine? Report

By creating a greater potential between inlet & jet pipe temperatures

By ensuring that the gas velocity is greater than the flame velocity

By ensuring that the flame velocity is greater than the gas velocity

19) During operation of the engine equipped with water injection system, the metering of the coolant to the system is Report

selected by the pilot

due to atmospheric pressure

due to altitude change

20) Water methanol injection is used Report

at high altitude take off conditions only

at a combination of higher than normal air temperatures and high altitude take off conditions

at higher than normal ambient air temperatures only

EASA Questions Mod 15: Gas Turbine Engine Set 15: Power Augmentation

Set 1: Fundamentals

Set 2: Engine Performance

Set 3: Engine Inlet

Set 4: Eng. compressors

Set 5: Combustion Section

Set 6: Turbine Section

Set 7: Engine Exhaust

Set 8: Bearing and Seals

Set 9: Lubricants and Fuel

Set 10: Lubrication system

Set 11: Fuel Systems

Set 12: Air Systems

Set 13: Ignition Systems

Set 14: Engine Indication

Set 15: Power Augmentation

Set 16:Turboprop engines

Set 17: Turboshaft

Set 18: APU

Set 19:Powerplant Installation

Set 20: Fire Protection

Set 21:Engine Monitoring

Set 22: Engine Storage