WorksheetsCPL PoF propeller revision
Total questions: 20
Worksheet time: 10mins
The propeller is a rotating aerofoil:
True
False
Blade angle is:
Angle between the chord line and the plane of rotation
Angle between the blade back and the plane of rotation
Angle between the chord line and RAF
Angle between the RAF and the blade back
The blade face is:
The side of the propeller blade facing away from the pilot
The side of the propeller blade facing toward the pilot
The leading edge of the propeller
Where the blade and the spinner meet
The angle between the RAF and the plane of rotation is known as:
AoA
Blade angle
Helix Angle
Angle of incidence
What is the purpose of helical twist?
A reduction in blade angle towards the propeller tip to maintain best thrust/torque ratio
An increase in blade angle towards the propeller tip to maintain best thrust/torque ratio
A reduction in blade angle towards the propeller tip to maintain 16° AoA for the entire blade length
An increase in blade angle towards the propeller tip to 16° AoA for the entire blade length
The most useful thrust is produced at approximately:
50% to blade radius
25% blade radius
75% blade radius
The entire blade radius assuming the propeller is twisted to maintain best AoA
An aircraft with a fixed pitch propeller is cruising at 120 knots and best cruise rpm. If the speed is increase without changing RPM what will happen to the AoA and efficiency of the propeller?
AoA will decrease and efficiency will increase
AoA will increase and efficiency will increase
AoA will decrease and efficiency will decrease
AoA will increase and efficiency will increase
The purpose of a constant speed unit is to:
Maintain the best thrust/torque ratio over a wide range of airspeeds
Maintain the lift/drag to torque ratio over a wide range of airspeeds
Maintain the best thrust/weight ratio over a wide range of airspeeds
Maintain 2700rpm at all airspeeds on all aircraft
In an aircraft with a CSU what is the correct technique to increase power?
Pitch/Rich/Power
Power/Pitch/Rich
Rich/Pitch/Power
Power/Rich/Pitch
A fixed pitch propeller with a coarse pitch will be more efficient at
High Speeds
Low Speeds
High Altitudes
Low Altitudes
What will happen to the propeller pitch in an aircraft fitted with a CSU if the pilot increases the manifold pressure?
The propeller pitch will fine in order to absorb more power
The propeller pitch will coarsen in order to absorb less power
The propeller pitch will fine in order to absorb less power
The propeller pitch will coarsen in order to absorb more power
The centrifugal twisting moment will:
Always act to fine the blade
Act to fine the blade in normal flight but coarsen the blade in windmilling flight
Always act to coarsen the blade
Act to coarsen the blade in normal flight but fine the blade in windmilling flight
Aerodynamic twisting moment will always act to fine the blade:
True
False
The asymmetric blade effect is caused by:
The up going blade traveling a greater distance
Asymmetric blade effect is only a factor on multi-engine aircraft
The down going blade traveling a greater distance
The tips of the blade traveling faster than the speed of sound
Propeller solidity is:
The amount of propellers attached to one engine
How strong a particular propeller is
Chord/Length
The amount of the propeller disc that is made up of solid propeller at a given radius
Select all the methods of increasing solidity:
More blades
Increase Chord
Contra-rotating propellers
Counter rotating propellers
Increase blade length
In windmilling flight:
The blade angle is so great that the TR acts in the opposite direction
The blade angle becomes negative and the TR acts in the opposite direction
The AoA is so great that the TR acts in the opposite direction
The AoA becomes negative and the TR acts in the opposite direction
With the propeller feathered:
Maximum drag is produced and no net torque is produced
Minimum drag is produced and no net torque is produced
Is the pitch setting for best cruise speed
Will increase the drag and reduce glide range
If power is applied while moving the propeller from normal flight to reverse thrust the propeller could overspeed
True
False
When operating in the pitch range for reverse thrust the propeller torque:
Is acting in the same direction as for windmilling flight
Is acting in the opposite direction as normal flight
Is acting to oppose engine torque
Is acting 90° to the plane of rotation
