Chapter 13: Engine Indication System

Question 1

what is engine pressure ratio?

Answer 1

index of thrust of engine

ratio of exhaust over inlet total pressure

Question 2

what is tachometer used for?

Answer 2

display of engine RPM

Question 3

how does N1 speed indication work?

Answer 3

EEC speed transducer supplies channels with N1 speed signal

Question 4

what does a magnetic pickup sensor do?

Answer 4

counts the blade passing and converts it to RPM (each gear teeth up and down)

Question 5

how does magnetic pickup sensor work?

Answer 5

conductor exposed to a changing magnetic field due to relative motion of field source

Question 6

what equipment is paired with the magnetic pickup sensor?

Answer 6

permanent magnetic alternator

Question 7

how is engine shaft vibration sensed by an accelerometer using a?

Answer 7

Piezo-Electric Transducer

Question 8

what is airborne vibration monitoring?

Answer 8

vibration rate of LP & HP shaft wrt RPM sensed by various sensors

Question 9

what does a fuel flow transmitter do?

Answer 9

indicate rate of fuel consumption in kg/hr per engine

measures fuel flow rate downstream of FCU

Question 10

purpose of HP fuel filter differential pressure indication

Answer 10

identify if filter is clogged with FOD in FCU

Question 11

when will signal appear for HP fuel filter differential pressure indicator?

Answer 11

inlet pressure > outlet pressure of filter

Question 12

what does the oil pressure transmitter do?

Answer 12

measures the pressure difference between supply and scavenge lines and indicate reading to cockpit

Question 13

what does the low oil pressure switch do?

Answer 13

sense pressure difference between supply and scavange lines and indicates on the cockpit

Question 14

what does the oil quantity transmitter do?

Answer 14

measures the quantity of oil in tank

Question 15

what does an oil filter differential pressure indication do?

Answer 15

identify if oil filter is clogged with FOD in oil filter housing

Question 16

when will signal appear for oil filter differential pressure indicator?

Answer 16

when inlet pressure > outlet pressure

Question 17

what is an oil temperature sensing bulb for?

Answer 17

measure oil temperature, if exceeds limit, engine will shut down

cockpit warning will appear if limit exceeded

Question 18

what does EGT indicate?

Answer 18

thermal load

Question 19

what will happen if EGT exceeds red zone?

Answer 19

hot section inspection

Question 20

how do engine measure EGT?

Answer 20

many probes to average the indication, even if 1 probe fails it will not affect reading

Question 21

purpose of PITOT tube?

Answer 21

supplies EEC with engine inlet temp and pressure (P2T2)

Question 22

torquemeter for turboprop & turboshaft indication

Answer 22

turboprop power output: torque & rpm for propeller blades

turboshaft engine output: torque & rpm for main rotor blade

Question 23

what is used to provide indication for torquemeter?

Answer 23

oil pressure

Question 24

what does primary, navigation, central display show?

Answer 24

primary: attitude, altitude, speed
navigation: heading & weather
central: engine, systems data, crew alert msg

Question 25

what is used to measure EGT?

Answer 25

thermocouple