Propeller

Question 1

320? - How is the propeller feathered by the ATPCS or the fire handle?

Answer 1

An electric feathering pump is electronically actuated to dump the metred oil pressure

Question 2

320? - What prevents power levers from being moved into the ground idle and reverse range in flight?

Answer 2

A flight idle gate that is controlled by the shock absorbers - at least one must be compressed in order to unlock the flight idle gate

Question 3

500 - The accessory gearbox (driven by the HP spool) drives the:

Answer 3

DC starter gen, engine driven fuel pump and oil pump

Question 4

320 - What is the purpose of the Electronic Control Unit (ECU)?

Answer 4

It controls fuel flow through the Hydro Mechanical Unit (HMU) by means of a stepper motor

Question 5

320/500 - What sub system handles the autofeathering of the prop?

Answer 5

320 - The Sinal Conditioning Unit (SCU)
500 - The Auto Feathering Unit (AFU)

Question 6

How is propeller pitch control achieved?

Answer 6

By opposing unmetred oil pressure against metred oil pressure