Chapter 7: Turboprop&shaft

Question 1

what is the output unit for turboprop and shaft?

Answer 1

shaft horse-power

Question 2

aviation application of turboshaft

Answer 2

APU & helicopters

Question 3

how many turbines will there be for turboprop and shaft engines

Answer 3

2, compressor turbine & free turbine

Question 4

amount of energy for engine and main gear box

Answer 4

2/3 goes to engine

1/3 goes to gear box

Question 5

what is the curvic coupling assembly?

Answer 5

conencts free turbine shaft to power output shaft

Question 6

advantages of turboprop engine

Answer 6

1) rapid acceleration for takeoff
2) efficient at low altitude and speed
3) short landing roll
4) high power to weight ratio
5) low vibration

Question 7

features of turboprop engine

Answer 7

1) gear reduction drive
2) reverse pitch
3) counter rotating spools
4) negative torque signals
5) thrust sensitive singals
6) free turbine

Question 8

what is a synchronophasing system for turboprop engines?

Answer 8

synchronise pitch angle between multiple propellers

Question 9

what does a negative torque signal do?

Answer 9

provide signals during signs of negative torque

Question 10

solution for negative torque?

Answer 10

increase propeller blade angle

Question 11

how does negative torque happen?

Answer 11

fuel disruption, wind forces, normal shutdown

Question 12

what does a thrust sensitive signal do?

Answer 12

safety feature that actuates propeller feather lever

increases blade angle to 90deg, feathers the propeller

Question 13

what is free turbine?

Answer 13

turbine not mechanically connected to compressor while extracting energy to do work

Question 14

reduction gear assembly components

Answer 14

1) drive shaft
2) NTS
3) TSS
4) propeller brake
5) dry sump oil system