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Select if the following statements are correct or incorrect .i when the ? [ Question security ]

Question 240-1 : I incorrect ii correct i correct ii incorrect i correct ii correct i incorrect ii incorrect

exemple 340 I. incorrect, ii. correctI. incorrect, ii. correct

For this question use the reference the diagram that correctly represents the ?

Question 240-2 : Diagram 3 diagram 2 diagram 1 diagram 4

.the blade angle known as 'feather' describes the pitch that results in no or slow rotation of the propeller at a specific flight condition typically cruise with the engine shut down .due to the twist of the blade this angle is typically slightly less than 90 degrees . /com en/com080 651 jpg /com en/com080 632 jpg. example . /com en/com080 651a jpg.saab sf340 inflight engine failure propeller feathered exemple 344 Diagram 3.Diagram 3.

For this question use the reference the diagram the letter which correctly ?

Question 240-3 : D c b a

. /com en/com080 636 jpg.helix angle the angle that the actual path of the propeller makes to the plane of rotation exemple 348 D.D.

For an aeroplane equipped with a two position variable pitch propeller it is ?

Question 240-4 : Fine pitch for take off and climb fine pitch for cruise coarse pitch for take off and climb fine pitch for cruise and coarse pitch for landing

. /com en/com080 1175 png. pitch control .coarse pitch is large blade angle low rpm and high forward airspeed .fine pitch is small blade angle high rpm and low forward airspeed exemple 352 Fine pitch for take-off and climb.Fine pitch for take-off and climb.

Propeller efficiency is ?

Question 240-5 : The ratio of power available thrust * tas to shaft power torque * rpm a number greater than one maximum when tas is zero greater with a larger number of blades

exemple 356 The ratio of power available (thrust * tas) to shaft power. (torque * rpm)The ratio of power available (thrust * tas) to shaft power. (torque * rpm)

Which of these statements concerning propellers is correct ?

Question 240-6 : The blade angle of a feathered propeller is approximately 90 degrees an unfeathered propeller causes less drag than a feathered propeller the blade angle of a feathered propeller is approximately 0 degrees a windmilling propeller causes less drag than a feathered propeller

.the propeller blade angle is the angle that the blade presents to the plane of rotation of the propeller the blade angle known as 'feather' describes the pitch that results in no or slow rotation of the propeller at a specific flight condition typically cruise with the engine shut down .due to the twist of the blade this angle is typically slightly less than 90 degrees . /com en/com080 651 jpg. example . /com en/com080 651a jpg.saab sf340 inflight engine failure propeller feathered exemple 360 The blade angle of a feathered propeller is approximately 90 degrees.The blade angle of a feathered propeller is approximately 90 degrees.

If s is the frontal area of the propeller disc propeller solidity is the ratio ?

Question 240-7 : The total frontal area of all the blades to s the frontal area of one blade to s s to the frontal area of one blade the mean chord of one blade to s

.propeller solidity the ratio of the total blade area to the disc area exemple 364 The total frontal area of all the blades to s.The total frontal area of all the blades to s.

Which statement about propeller noise is correct .i propeller noise increases ?

Question 240-8 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is correct i is incorrect ii is incorrect

.a propeller must be able to absorb all the shaft power developed by the engine and also operate with maximum efficiency throughout the required performance envelope of the aircraft the critical factor is tip velocity if tip velocity is too high the blade tips will approach the local speed of sound and compressibility effects will decrease thrust and increase rotational drag supersonic tip speed will considerably reduce the efficiency of a propeller and greatly increase the noise it generates .in most installations increasing the number of blades helps to reduce noise cockpit noise comes from a variety of sources engine exhaust slipstream and the propeller vibrations are also perceived as noise in the cockpit a two blade propeller produces an inherent once per revolution vibration that shakes the airframe so a three blade propeller will be inherently smoother and therefore quieter etc exemple 368 I is correct, ii is correct.I is correct, ii is correct.

Which statement is correct regarding the gyroscopic effect of a clockwise ?

Question 240-9 : I is incorrect ii is incorrect i is correct ii is incorrect i is incorrect ii is correct i is correct ii is correct

Gyroscopic effect works like this .if an up force is applied to the tail plane causing nose pitch down that would be the same as applying a forward force to the 12 o'clock position on the prop to cause the pitch down if this was a right hand propeller clockwise when viewed from the rear this force would then act at the 3 o'clock postion on the propeller in a forwards movement causing a yaw to the left .in this image try to imagine the forward force at any position and the effect that it will have on the attitude of flight . /com en/com080 607a png. clockwise propeller when viewed from the rear . /com en/com080 607 png. exemple 372 I is incorrect, ii is incorrect.I is incorrect, ii is incorrect.

The asymmetric blade effect on an single engine aeroplane with a clockwise ?

Question 240-10 : Produces left yaw does not produce any yaw produces right yaw is also called the gyroscopic effect

exemple 376 Produces left yaw.Produces left yaw.

The geometric pitch of a propeller is the ?

Question 240-11 : Theoretical distance a propeller would advance in one revolution at zero blade angle of attack distance a propeller would have to advance in one revolution to give no thrust the angle between the chordline of a blade element and the propeller plane of rotation distance a propeller advances with slippage

.if the propeller were to rotate one turn like a cork screw into a bottle of wine geometric pitch would be how far it travels into the cork if you can ignore tas and speed it is just a consideration of the blade angle and one rotation however it would not be a true distance at all stages of rotation like a corkscrew exemple 380 Theoretical distance a propeller would advance in one revolution at zero blade angle of attack.Theoretical distance a propeller would advance in one revolution at zero blade angle of attack.

For a given rpm of a fixed pitch propeller the blade angle of attack will ?

Question 240-12 : Decrease when the tas increases increase when the tas increases remain constant when the tas increases remain constant when the tas decreases

.for a fixed pitch propeller the pitch angle cannot be changed it varies from root to tip to maintain near constant angle of attack along the blade .the angle of attack as in the case of a aircraft wing is defined as the angle between the chord line and relative airflow with a propeller however the relative airflow is the resultant of the airflow due to rotation and forward speed change either of these values and the angle of attack will change . /com en/com080 549 jpg. exemple 384 Decrease when the tas increases.Decrease when the tas increases.

For a fixed pitch propeller in flight at a given tas the blade angle of attack ?

Question 240-13 : Increase if rpm increases decrease if rpm increases remain constant if rpm increases remain constant if rpm decreases

.for a fixed pitch propeller the pitch angle cannot be changed it varies from root to tip to maintain near constant angle of attack along the blade .the angle of attack as in the case of a aircraft wing is defined as the angle between the chord line and relative airflow with a propeller however the relative airflow is the resultant of the airflow due to rotation and forward speed change either of these values and the angle of attack will change . /com en/com080 549 jpg. exemple 388 Increase if rpm increases.Increase if rpm increases.

Which statement is correct for a propeller of given diameter and at constant ?

Question 240-14 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is correct i is incorrect ii is incorrect

exemple 392 I is correct, ii is correct.I is correct, ii is correct.

Which statement about a propeller is correct .i asymmetric blade effect ?

Question 240-15 : I is correct ii is correct i is incorrect ii is correct i is correct ii is incorrect i is incorrect ii is incorrect

.when an aircraft is flying with a high angle of attack the 'bite' of the downward moving blade is greater than the 'bite' of the upward moving blade this moves the center of thrust to the right of the prop disc area causing a yawing moment toward the left around the vertical axis to prove this explanation is complex because it would be necessary to work wind vector problems on each blade while considering both the angle of attack of the aircraft and the angle of attack of each blade .this asymmetric loading is caused by the resultant velocity which is generated by the combination of the velocity of the propeller blade in its plane of rotation and the velocity of the air passing horizontally through the propeller disc with the aircraft being flown at positive aoas the right viewed from the rear or downswinging blade is passing through an area of resultant velocity which is greater than that affecting the left or upswinging blade .since the propeller blade is an airfoil increased velocity means increased lift the downswinging blade has more lift and tends to pull yaw the aircraft's nose to the left .when the aircraft is flying at a high angle of attack the downward moving blade has a higher resultant velocity creating more lift than the upward moving blade . /com en/com080 663 jpg.this might be easier to visualize if the propeller shaft was mounted perpendicular to the ground like a helicopter if there were no air movement at all except that generated by the propeller itself identical sections of each blade would have the same airspeed with air moving horizontally across this vertically mounted propeller the blade proceeding forward into the flow of air has a higher airspeed than the blade retreating with the airflow thus the blade proceeding into the horizontal airflow is creating more lift or thrust moving the center of thrust toward that blade visualize rotating the vertically mounted propeller shaft to shallower angles relative to the moving air as on an aircraft this unbalanced thrust then becomes proportionately smaller and continues getting smaller until it reaches the value of zero when the propeller shaft is exactly horizontal in relation to the moving air .the effects of each of these four elements of torque vary in value with changes in flight situations in one phase of flight one of these elements may be more prominent than another in another phase of flight another element may be more prominent the relationship of these values to each other varies with different aircraft depending on the airframe engine and propeller combinations as well as other design features to maintain positive control of the aircraft in all flight conditions the pilot must apply the flight controls as necessary to compensate for these varying values exemple 396 I is correct, ii is correct.I is correct, ii is correct.

Which statement is correct regarding a propeller .i increasing tip speed to ?

Question 240-16 : I is correct ii is incorrect i is correct ii is correct i is incorrect ii is correct i is incorrect ii is incorrect

.a propeller must be able to absorb all the shaft power developed by the engine and also operate with maximum efficiency throughout the required performance envelope of the aircraft the critical factor is tip velocity if tip velocity is too high the blade tips will approach the local speed of sound and compressibility effects will decrease thrust and increase rotational drag supersonic tip speed will considerably reduce the efficiency of a propeller and greatly increase the noise it generates exemple 400 I is correct, ii is incorrect.I is correct, ii is incorrect.

The blade angle of a propeller is usually referenced at ?

Question 240-17 : 75 % of blade radius 50 % of blade radius 25 % of blade radius 99 % of blade radius

.the blade angle is the angle formed between the propeller's plane of rotation and the chord line of its airfoil section it is expressed in degrees usually measured at 75% of the blade's radius exemple 404 75 % of blade radius.75 % of blade radius.

Which statement is correct .i a propeller with a small blade angle is referred ?

Question 240-18 : I is correct ii is correct i is incorrect ii is correct i is correct ii is incorrect i is incorrect ii is incorrect

.the reason a propeller is 'twisted' is that the outer parts of the propeller blades like all things that turn about a central point travel faster than the portions near the hub if the blades had the same geometric pitch throughout their lengths portions near the hub could have negative aoas while the propeller tips would be stalled at cruise speed twisting or variations in the geometric pitch of the blades permits the propeller to operate with a relatively constant aoa along its length when in cruising flight .propeller blades are twisted to change the blade angle in proportion to the differences in speed of rotation along the length of the propeller keeping thrust more nearly equalized along this length .'little blade twist' is not refered to 'fine pitch' it refers to variation of the angle of attack along the lenght of the blade .coarse pitch is large blade angle .fine pitch is small blade angle . 885. exemple 408 I is correct, ii is correct.I is correct, ii is correct.

Which statement is correct .i a propeller with little blade twist is referred ?

Question 240-19 : I is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is incorrect i is correct ii is correct

.the reason a propeller is 'twisted' is that the outer parts of the propeller blades like all things that turn about a central point travel faster than the portions near the hub if the blades had the same geometric pitch throughout their lengths portions near the hub could have negative aoas while the propeller tips would be stalled at cruise speed twisting or variations in the geometric pitch of the blades permits the propeller to operate with a relatively constant aoa along its length when in cruising flight .propeller blades are twisted to change the blade angle in proportion to the differences in speed of rotation along the length of the propeller keeping thrust more nearly equalized along this length .'little blade twist' is not refered to 'fine pitch' it refers to variation of the angle of attack along the lenght of the blade .coarse pitch is large blade angle .fine pitch is small blade angle . 885. exemple 412 I is incorrect, ii is incorrect.I is incorrect, ii is incorrect.

Which statement is correct .i propeller gyroscopic effect occurs during ?

Question 240-20 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is correct i is incorrect ii is incorrect

.propeller gyroscopic effect occurs during aeroplane pitch changes gyroscopic effect works like this .if an up force is applied to the tail plane causing nose pitch down that would be the same as applying a forward force to the 12 o'clock position on the prop to cause the pitch down if this was a right hand propeller clockwise when viewed from the rear this force would then act at the 3 o'clock postion on the propeller in a forwards movement causing a yaw to the left .propeller gyroscopic effect is most noticeable during low speed flight at high propeller rpm since at high speed a higher force is required to counteract the stability of the aircraft exemple 416 I is correct, ii is correct.I is correct, ii is correct.

Which statement is correct when comparing a fixed pitch propeller with a ?

Question 240-21 : I is correct ii is incorrect i is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is correct

.a constant speed propeller maintains near maximum efficiency over a wider range of aeroplane speeds than a fixed pitch propeller therefore a constant speed propeller reduces fuel consumption over a range of cruise speeds . /com en/com080 1175 png. pitch control .coarse pitch is large blade angle low rpm and high forward airspeed .fine pitch is small blade angle high rpm and low forward airspeed exemple 420 I is correct, ii is incorrect.I is correct, ii is incorrect.

Which of these statements concerning propellers is correct ?

Question 240-22 : When compared with a non feathered propeller a feathered propeller improves the handling of a multi engine aeroplane with one engine inoperative the blade angle of a feathered propeller is approximately 180 degrees the blade angle of a feathered propeller is approximately 0 degrees a windmilling propeller causes less drag than a feathered propeller

.following an engine failure on a twin engine aeroplane the increased drag from the windmilling propeller will seriously degrade climb performance limit range and add to the yawing moment caused by the failed engine which will affect controllability also by continuing to turn a badly damaged engine eventual seizure of the engine or an engine fire might result .drag from a windmilling propeller is high it is being driven by the relative airflow and is generating both drag and torque a feathered propeller generates the least drag there is no torque because it is not rotating and the parasite drag is a minimum because the blades are edge on to the relative airflow .the blade angle known as 'feather' describes the pitch that results in no or slow rotation of the propeller at a specific flight condition typically cruise with the engine shut down .due to the twist of the blade this angle is typically slightly less than 90 degrees . /com en/com080 651 jpg /com en/com080 632 jpg. example . /com en/com080 651a jpg.saab sf340 inflight engine failure propeller feathered exemple 424 When compared with a non-feathered propeller, a feathered propeller improves the handling of a multi-engine aeroplane with one engine inoperative.When compared with a non-feathered propeller, a feathered propeller improves the handling of a multi-engine aeroplane with one engine inoperative.

The effective pitch of a propeller is the ?

Question 240-23 : Actual distance a propeller advances in one revolution theoretical distance a propeller would advance in one revolution at zero blade angle of attack angle between the chordline of a blade element and the propeller plane of rotation the distance a propeller advances with slippage

. 907.effective pitch is the actual distance a propeller advances in one revolution in the air the effective pitch is always shorter than geometric pitch due to the air is a fluid and always slip exemple 428 Actual distance a propeller advances in one revolution.Actual distance a propeller advances in one revolution.

Which statement is correct .i propeller gyroscopic effect occurs during ?

Question 240-24 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is correct i is incorrect ii is incorrect

.propeller gyroscopic effect occurs during aeroplane pitch changes gyroscopic effect works like this .if an up force is applied to the tail plane causing nose pitch down that would be the same as applying a forward force to the 12 o'clock position on the prop to cause the pitch down if this was a right hand propeller clockwise when viewed from the rear this force would then act at the 3 o'clock postion on the propeller in a forwards movement causing a yaw to the left .propeller gyroscopic effect is most noticeable during low speed flight at high propeller rpm since at high speed a higher force is required to counteract the stability of the aircraft exemple 432 I is correct, ii is correct.I is correct, ii is correct.

Which statement about a propeller is correct .i asymmetric blade effect is ?

Question 240-25 : I is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is correct i is correct ii is incorrect

exemple 436 I is incorrect, ii is incorrect.I is incorrect, ii is incorrect.

Which of these statements about propellers is correct or incorrect .i a cruise ?

Question 240-26 : I is correct ii is correct i is incorrect ii is incorrect i is correct ii is incorrect i is incorrect ii is correct

. /com en/com080 1175 png. pitch control .coarse pitch is large blade angle low rpm and high forward airspeed .fine pitch is small blade angle high rpm and low forward airspeed exemple 440 I is correct, ii is correct.I is correct, ii is correct.

Which statement is correct regarding a windmilling propeller on a multi engine ?

Question 240-27 : The windmilling drag is much higher than for a feathered propeller a windmilling propeller hardly affects low speed controllability the drag of a windmilling and a feathered propeller is almost the same the windmilling drag is only significant at negative blade angles

.following an engine failure on a twin engine aeroplane the increased drag from the windmilling propeller will seriously degrade climb performance limit range and add to the yawing moment caused by the failed engine which will affect controllability also by continuing to turn a badly damaged engine eventual seizure of the engine or an engine fire might result .drag from a windmilling propeller is high it is being driven by the relative airflow and is generating both drag and torque a feathered propeller generates the least drag there is no torque because it is not rotating and the parasite drag is a minimum because the blades are edge on to the relative airflow .the blade angle known as 'feather' describes the pitch that results in no or slow rotation of the propeller at a specific flight condition typically cruise with the engine shut down .due to the twist of the blade this angle is typically slightly less than 90 degrees . /com en/com080 651 jpg /com en/com080 632 jpg. example . /com en/com080 651a jpg.saab sf340 inflight engine failure propeller feathered exemple 444 The windmilling drag is much higher than for a feathered propeller.The windmilling drag is much higher than for a feathered propeller.

The angle of attack of a rotating propeller blade element shown in the annex is ?

Question 240-28 : Angle 1 angle 2 angle 3 not correctly indicated in the diagram

. /com en/com080 973 jpg. exemple 448 Angle 1.Angle 1.

The helix or advance angle of a rotating propeller blade element shown in the ?

Question 240-29 : Angle 3 angle 2 angle 1 not correctly indicated in the diagram

. /com en/com080 973 jpg. exemple 452 Angle 3.Angle 3.

The blade angle of a rotating propeller blade element shown in the annex is . ?

Question 240-30 : Angle 2 angle 3 angle 1 not correctly indicated in the diagram

. /com en/com080 973 jpg. exemple 456 Angle 2.Angle 2.

Propeller blade twist is the ?

Question 240-31 : Varying of the blade angle from the root to the tip of a propeller blade angle between the relative airflow and the propeller blade's angle of attack varying of the helix angle from the root to the tip of a propeller blade angle between the blade angle and the direction of the flight of the aeroplane

.the pitch angle varies from root to tip to maintain a near constant angle of attack along the blade .the reason a propeller is 'twisted' is that the outer parts of the propeller blades like all things that turn about a central point travel faster than the portions near the hub if the blades had the same geometric pitch throughout their lengths portions near the hub could have negative aoas while the propeller tips would be stalled at cruise speed twisting or variations in the geometric pitch of the blades permits the propeller to operate with a relatively constant aoa along its length when in cruising flight .propeller blades are twisted to change the blade angle in proportion to the differences in speed of rotation along the length of the propeller keeping thrust more nearly equalized along this length exemple 460 Varying of the blade angle from the root to the tip of a propeller blade.Varying of the blade angle from the root to the tip of a propeller blade.

A rotating propeller blade element produces an aerodynamic force f that may be ?

Question 240-32 : Diagram 1 diagram 2 diagram 3 diagram 4

. /com en/com080 1001 gif. exemple 464 Diagram 1.Diagram 1.

A rotating propeller blade element produces an aerodynamic force f that may be ?

Question 240-33 : Diagram 2 diagram 3 diagram 1 diagram 4

. /com en/com080 1001 gif.

A rotating propeller blade element produces an aerodynamic force f that may be ?

Question 240-34 : Diagram 4 diagram 3 diagram 2 diagram 1

. /com en/com080 1001 gif. exemple 472 Diagram 4.Diagram 4.

The variation of propeller efficiency of a fixed pitch propeller with tas at a ?

Question 240-35 : Figure 4 figure 1 figure 2 figure 3

. /com en/com080 1018 jpg.variation of propeller efficiency of a fixed pitch propeller exemple 476 Figure 4.Figure 4.

Which statement is correct regarding a propeller .i increasing tip speed to ?

Question 240-36 : I is incorrect ii is incorrect i is correct ii is correct i is incorrect ii is correct i is correct ii is incorrect

A propeller must be able to absorb all the shaft power developed by the engine and also operate with maximum efficiency throughout the required performance envelope of the aircraft the critical factor is tip velocity if tip velocity is too high the blade tips will approach the local speed of sound and compressibility effects will decrease thrust and increase rotational drag supersonic tip speed will considerably reduce the efficiency of a propeller and greatly increase the noise it generates .in most installations increasing the number of blades helps to reduce noise cockpit noise comes from a variety of sources engine exhaust slipstream and the propeller vibrations are also perceived as noise in the cockpit a two blade propeller produces an inherent once per revolution vibration that shakes the airframe so a three blade propeller will be inherently smoother and therefore quieter etc exemple 480 I is incorrect, ii is incorrect.I is incorrect, ii is incorrect.

Which statement is correct .i at a given rpm the propeller efficiency of a ?

Question 240-37 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is correct i is incorrect ii is incorrect

.for a fixed pitch propeller the pitch angle cannot be changed it varies from root to tip to maintain near constant angle of attack along the blade at a given rpm the propeller efficiency of a fixed pitch propeller is maximum at only one value of tas when a constant speed propeller maintains near maximum efficiency over a wider range of aeroplane speeds . /com en/com080 1175 png. constant speed propeller pitch control .coarse pitch is large blade angle low rpm and high forward airspeed .fine pitch is small blade angle high rpm and low forward airspeed exemple 484 I is correct, ii is correct.I is correct, ii is correct.

Which statement is correct when comparing a fixed pitch propeller with a ?

Question 240-38 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is correct i is incorrect ii is incorrect

.a constant speed propeller maintains near maximum efficiency over a wider range of aeroplane speeds than a fixed pitch propeller therefore a constant speed propeller reduces fuel consumption over a range of cruise speeds . /com en/com080 1175 png. pitch control .coarse pitch is large blade angle low rpm and high forward airspeed .fine pitch is small blade angle high rpm and low forward airspeed .a coarse fixed pitch propeller improves cruise performance not take off and climb performances exemple 488 I is correct, ii is correct.I is correct, ii is correct.

Which statement is correct regarding a propeller .i increasing tip speed to ?

Question 240-39 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is correct i is incorrect ii is incorrect

.a propeller must be able to absorb all the shaft power developed by the engine and also operate with maximum efficiency throughout the required performance envelope of the aircraft the critical factor is tip velocity if tip velocity is too high the blade tips will approach the local speed of sound and compressibility effects will decrease thrust and increase rotational drag supersonic tip speed will considerably reduce the efficiency of a propeller and greatly increase the noise it generates .in most installations increasing the number of blades helps to reduce noise cockpit noise comes from a variety of sources engine exhaust slipstream and the propeller vibrations are also perceived as noise in the cockpit a two blade propeller produces an inherent once per revolution vibration that shakes the airframe so a three blade propeller will be inherently smoother and therefore quieter etc exemple 492 I is correct, ii is correct.I is correct, ii is correct.

Which statement about propeller icing is correct .i propeller icing increases ?

Question 240-40 : I is correct ii is correct i is correct ii is incorrect i is incorrect ii is incorrect i is incorrect ii is correct

exemple 496 I is correct, ii is correct.I is correct, ii is correct.

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