Electrical And Indicating System

Question 1

Systems that are monitored on a basic GTE are

Answer 1

Engine temp
Oil pressure and oil temp
Engine RPM
Torque
Engine pressure ratio
Fuel flow
Vibration

Question 2

How is the JPT jet pipe temperature

Answer 2

Takes signals from either a set of thermocouples, or pyrometers

Question 3

What is this

• Transmit temperature signal to the indicator
• two dissimilar wires
• signal is transmitted to a junction box and amplified then displayed in the cockpit at degrees Celsius
• measures temp before before enter the exhaust

Answer 3

Thermocouples

Question 4

What is this

• Optical device that veiws the turbine blades
• it enables rapid, accurate measurement of temperature
• requires bleed air

Answer 4

Pyrometer

Question 5

How is oil temperature sensed

Answer 5

• Temp sensitive element fitted
• change in resistance

Question 6

How is oil pressure transmitted

Answer 6

To an indicator on the instrument panel
- flag indicator = indicates if pressure is high low or medium
- digital type gauge = calibration in pounds per square inch PSI

Question 7

How does it read engine RPM

Answer 7

• small electrical generator driven from external gearbox
• As a percentage

Question 8

How is torque displayed

Answer 8

• torque pressure PSI
• Torque percentage

Question 9

What does the engine pressure ratio EPR measure

Answer 9

• The ratio between the turbine discharge pressure and the compressor inlet pressure
• amounts of thrust it is producing

Question 10

What is this

Sensed by piezoelectric accelerometers which contain a material that produces an electric current when squeezed by the forces produced by …… (what’s this word)

Answer 10

Vibration

Vibration detection system

Question 11

Whats the modern day technology for instrumentation

Answer 11

Liquid crystal display technology = all displayed on one screen