1) A bypass engine LP compressor Report

supplies less air than is required for combustion

supplies more air than is required for combustion

supplies only the required quantity of air for combustion

2) How does a dual axial flow compressor improve the efficiency of a turbojet engine? Report

by increasing the velocity of the air entering the combustion chamber

by using more turbine wheels

by obtaining High compression ratios

3) In a reverse flow system, the last stage of an axial flow compressor is often centrifugal. This is to Report

provide initial turning of the airflow

prevent compressor surge

increase the temperature rise

4) What are the two main functional components in a centrifugal compressor? Report

Bucket and expander

Impeller and diffuser

Turbine and compressor

5) A bypass ratio of 5:1 indicates that the bypass flow is Report

equal to 1/5 of the hot stream

five times the hot stream

five times the cold stream

6) The stator vanes in an axial-flow compressor Report

direct air into the first stage rotor vanes at the proper angle

convert velocity energy into pressure energy

convert pressure energy onto velocity energy

7) What units in a gas turbine engine aid in stabilisation of the compressor during low thrust engine operations? Report

Stator vanes

Inlet guide vanes

Bleed air valves

8) What purpose do the diffuser vanes of a centrifugal compressor serve? Report

Convert pressure energy into kinetic energy

Increase the air velocity

Convert kinetic energy into Pressure energy

9) During the high RPM range on an axial flow gas turbine engine, in what position are the variable intake guide vanes and bleed valves?. Report

At maximum swirl position, bleed valves open

At minimum swirl position, bleed valves closed

At maximum swirl position, bleed valves closed

10) What is the purpose of the diffuser section in a turbine engine? Report

To convert pressure to velocity

To reduce pressure and increase velocity

To increase pressure and reduce velocity

11) The fan speed of a twin spool axial compressor engine is the same as the Report

low pressure compressor

high pressure compressor

forward turbine wheel

12) Bleed valves are normally spring loaded to the Report

closed position

open position

mid-position

13) What is the function of the stator vane assembly at the discharge end of a typical axial flow compressor? Report

To increase air swirling motion into the combustion chambers

To direct the flow of gases into the combustion chambers

To straighten airflow to eliminate turbulence

14) In a turbine engine with a dual spool compressor, the low speed compressor Report

always turns at the same speed as the high speed compressor

seeks its own best operating speed

is connected directly to the high speed compressor.

15) What units in a gas turbine engine aid in guiding the airflow during low thrust engine operations? Report

Stator vanes

Bleed air valves

Inlet guide vanes

16) The purpose of the stator blades in the compressor section is to Report

increase the airflow velocity

stabilize the airflow pressure

control the airflow direction

17) Compressor stall is caused by Report

low angle of attack airflow through the first stages of compression

rapid engine deceleration

a high angle of attack airflow through the first stages of compression

18) What is used to aid in stabilization of compressor airflow? Report

Variable guide vanes and/or compressor bleed valves

Pressurization and dump valves

Stator vanes and rotor vanes

19) What is the primary factor that controls the pressure ratio of an axial flow compressor?. Report

Compressor inlet temperature

Compressor inlet pressure

Number of stages in compressor

20) The non-rotating axial-flow compressor airfoils in an aircraft gas turbine engine are known as. Report

stator vanes

bleed vanes

pressurization vanes

EASA Questions Mod 15: Gas Turbine Engine Set 4: Eng. Compressors

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