Sensors

Question 1

Torquemeter sensor

Answer 1

• Two monopole torque sensors (that go to FADEC A and FADEC B) sense the engines output torque
• They are mounted at the front of the torquemeter housing at the 3 and 9 o’clock position
• they are the secondary source for measuring power turbine speed (NP)

Question 2

Gas generator (Ng) speed sensor

Answer 2

• Two monopole sensors (that go to fadec A and fadec B) sense the speed of the gas generator (Ng) by the speed of the starter drive gearbox
• They are mounted on the RH side of the PUAD on the PUAD gearbox

Question 3

Power Turbine (Np) Speed Sensor

Answer 3

• One dual coil magnetic pickup this allows each FADEC to receive its own independent signal
• The Np speed pickup is flange mounted to the aft sump cover of the power turbine

Question 4

Measured Gas Temperature (MGT) Thermocouples

Answer 4

• There are 16 thermocouples
• They are inserted though the power turbine case and into the power turbine third-stage vane assemblies
• The power turbine case has 19 openings and they are numbered 1 though 19 clockwise from the rear
• 8 go to FADEC A (4, 7, 9, 12, 13, 14, 17 and 19), 8 go to FADEC B (1, 3, 5, 6, 8, 11, 15, and 16) and 3 are borescope plugs (2, 10 and 16)

Question 5

Fuel Flow (WF)

Answer 5

• Measures engine fuel flow rate from the flowmeter
• It’s the fuel flowmeter sensor located at the lower left of the compressor case
• sends info to the EMS harness

Question 6

Propeller Gearbox Oil Pressure (GBOILP)

Answer 6

• Senses PGB oil pressure from the oil pressure transducer
• This is on the left side of the PGB lube and scavenge pump
• sends info to the EMS harness

Question 7

Power Section Oil Pressure (PSOILP)

Answer 7

• Senses power section (also known as “engine”) Oil Pressure from the oil pressure transducer
• this on the left rear of the power section lube and scavenge pump
• sends info to the EMS harness

Question 8

Fuel Filter Impending Bypass (FFIB)

Answer 8

• the sensor in the fuel pump and metering unit (FPMU)
• it’s located at the top front of the fuel pump and metering unit (FPMU)
• it’s a combination of electrical(sends a signal to the EMS harness) and mechanical (the red button pops) type

Question 9

Fuel Temperature (WFT)

Answer 9

• the switch on the fuel-cooled oil cooler (FCOC)
• it’s the switch located at the front of the FCOC
• sends the info to the EMS harness

Question 10

Spark Rate-ignition Exciter A (SPKA)

Answer 10

• the spark rate sensor in the left ignition exciter

* sends the info to the EMS harness

Question 11

Spark Rate-Ignition Exciter (SPKB)

Answer 11

• the spark rate sensor in the right ignition exciter

* sends the info to the EMS harness

Question 12

Compressor Discharge Pressure (CDP)

Answer 12

• the compressor discharge pressure sensor at the lower left of the diffuser
• sends its info to the EMS harness

Question 13

Compressor Discharge Temperature (CDT)

Answer 13

• the compressor Discharge Temperature sensor at the lower right of the compressor diffuser
• sends its info to the EMS harness

Question 14

Propeller Gearbox Vibration (GVIB)

Answer 14

• the Vibration sensor located at the lower right of the propeller gearbox
• sends its info to the EMS harness

Question 15

Compressor Vibration (CVIB)

Answer 15

• the Vibration sensor at the bottom of the compressor diffuser
• sends info to the EMS harness

Question 16

Turbine Vibration (TVIB)

Answer 16

• the Vibration sensor at the bottom of the power turbine

* sends info to EMS harness