BAKERS ORAL POWERPLANT UPDATED
COMPLETE QUESTIONS AND ANSWERS
ALREADY PASSED GRADED A+
●● Where does the APU fuel supply normally come from?
Answer: The airplane's main fuel supply.
●● How is the APU rotated during start up?
Answer: With an electric starter.
●● What is the function of an APU air inlet plentum?
Answer: To stabilize the pressure of the air before it enters the
compressor.
●● When operating at high loads, what is the speed of an APU?
Answer: The APU remains at or near rated speed regardless of the load
condition.
●● What is the effect of the pneumatic power when being used in
conjunction with maximum APU shaft power output?
Answer: The pneumatic loading will be automatically modulated to
maintain a safe EGT.
,●● Before shut down, how would APU cooling be accomplished?
Answer: By closing the bleed air valve.
●● When is most of the load placed on an APU?
Answer: When the bleed air is open.
●● What regulates fuel scheduling during APU start and under varying
pneumatic bleed and electrical loads?
Answer: Fuel scheduling is maintained automatically by the APU fuel
control system.
●● What is the primary function of the load compressor on APU's
equipped with a free turbine and load compressor?
Answer: To provide bleed air for aircraft pneumatic systems.
●● To prevent rotor seizure "shock cooling", how long should an APU
idle before being shut down?
Answer: 3 to 5 minutes.
●● What is the purpose of a propeller?
Answer: To create thrust and either pull or push the airplane through the
air.
,●● What are the two types of propeller configurations?
Answer: The Tractor type and the Pusher type.
●● What type of propeller has the blade angle built into the propeller
and cannot be changed?
Answer: A fixed pitch propeller.
●● What is the purpose of the metal tipping on a leading edge of a
wooden propeller?
Answer: To protect the propeller form damage caused by foreign object
damage.
●● What tool is used to determine propeller blade angle?
Answer: A Protractor.
●● What are the aerodynamic forces and loads acting on a rotating
propeller blade?
Answer: Centrifugal force, aerodynamic twisting, centrifugal twisting,
torque bending, and thrust bending forces.
●● What is the meaning of propeller blade "back" and "face"?
Answer: The curved side of the propeller is the blade back. The flat side
is the blade face.
, ●● What should be used to clean aluminum and steel propeller blades
and hubs?
Answer: They should be washed with a suitable cleaning solvent using a
brush or cloth.
●● What positions are used on a balance stand to check a two bladed
propeller for static balance?
Answer: First the vertical position, and then the horizontal position.
●● Can fixed pitch propeller's pitch be changed?
Answer: No, they are fixed at a specific pitch angle.
●● Why do you put the blades of a counterweight propeller into high
pitch before stopping the engine?
Answer: Because in this position, the piston is protected from dirt and
moisture in the air.
●● Why are cones installed on splinted shafts with a propeller?
Answer: The cones center the propeller on the shaft as they are forced
toward each other by the tightening of the retaining nut.
●● How is feathering accomplished on a constant speed counterweight
propeller?
Answer: By releasing governor oil pressure on the counterweights.
COMPLETE QUESTIONS AND ANSWERS
ALREADY PASSED GRADED A+
●● Where does the APU fuel supply normally come from?
Answer: The airplane's main fuel supply.
●● How is the APU rotated during start up?
Answer: With an electric starter.
●● What is the function of an APU air inlet plentum?
Answer: To stabilize the pressure of the air before it enters the
compressor.
●● When operating at high loads, what is the speed of an APU?
Answer: The APU remains at or near rated speed regardless of the load
condition.
●● What is the effect of the pneumatic power when being used in
conjunction with maximum APU shaft power output?
Answer: The pneumatic loading will be automatically modulated to
maintain a safe EGT.
,●● Before shut down, how would APU cooling be accomplished?
Answer: By closing the bleed air valve.
●● When is most of the load placed on an APU?
Answer: When the bleed air is open.
●● What regulates fuel scheduling during APU start and under varying
pneumatic bleed and electrical loads?
Answer: Fuel scheduling is maintained automatically by the APU fuel
control system.
●● What is the primary function of the load compressor on APU's
equipped with a free turbine and load compressor?
Answer: To provide bleed air for aircraft pneumatic systems.
●● To prevent rotor seizure "shock cooling", how long should an APU
idle before being shut down?
Answer: 3 to 5 minutes.
●● What is the purpose of a propeller?
Answer: To create thrust and either pull or push the airplane through the
air.
,●● What are the two types of propeller configurations?
Answer: The Tractor type and the Pusher type.
●● What type of propeller has the blade angle built into the propeller
and cannot be changed?
Answer: A fixed pitch propeller.
●● What is the purpose of the metal tipping on a leading edge of a
wooden propeller?
Answer: To protect the propeller form damage caused by foreign object
damage.
●● What tool is used to determine propeller blade angle?
Answer: A Protractor.
●● What are the aerodynamic forces and loads acting on a rotating
propeller blade?
Answer: Centrifugal force, aerodynamic twisting, centrifugal twisting,
torque bending, and thrust bending forces.
●● What is the meaning of propeller blade "back" and "face"?
Answer: The curved side of the propeller is the blade back. The flat side
is the blade face.
, ●● What should be used to clean aluminum and steel propeller blades
and hubs?
Answer: They should be washed with a suitable cleaning solvent using a
brush or cloth.
●● What positions are used on a balance stand to check a two bladed
propeller for static balance?
Answer: First the vertical position, and then the horizontal position.
●● Can fixed pitch propeller's pitch be changed?
Answer: No, they are fixed at a specific pitch angle.
●● Why do you put the blades of a counterweight propeller into high
pitch before stopping the engine?
Answer: Because in this position, the piston is protected from dirt and
moisture in the air.
●● Why are cones installed on splinted shafts with a propeller?
Answer: The cones center the propeller on the shaft as they are forced
toward each other by the tightening of the retaining nut.
●● How is feathering accomplished on a constant speed counterweight
propeller?
Answer: By releasing governor oil pressure on the counterweights.
