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The stall speed line in the manoeuvring load diagram runs through a point where ? [ Formation assignment ]

Question 239-1 : Speed = vs load factor = +1 speed = vb load factor = +1 speed = va load factor = +1 speed = 0 load factor = +1

.the stall line runs from n=0 airspeed=0 and 0g to +2 5g the normal limit load factor at the speed of va . 2767.the stall speed line runs through the point speed = vs load factor = +1 . joangoris .there's another question where it asks the same and the correct answer is va not vs .i don't understand any help thanks . .you are talking about the following question . the stall speed line in the manoeuvring load diagram runs through a point where the .right answer speed = va load factor = limit load factor .the stall line starts at a point where load factor = 0 and airspeed = 0 and runs through a point where the load factor reaches limit load factor for a large aeroplane +2 5g .this point is va design manoeuvring speed .here since the answer speed = va load factor = limit load factor is not offered the only correct one is speed = vs load factor = +1 exemple 339 Speed = vs, load factor = +1.Speed = vs, load factor = +1.

Which of these statements about flutter are correct or incorrect .i moving the ?

Question 239-2 : I is incorrect ii is incorrect i is correct ii is correct i is incorrect ii is correct i is correct ii is incorrect

.flutter is a dangerous phenomenon encountered in flexible structures subjected to aerodynamic forces as the airspeed increases there may be a point at which the structural damping is insufficient to damp out the motions which are increasing due to aerodynamic energy being added to the airfoil this vibration can cause structural failure and therefore considering flutter characteristics is an essential part of designing an aircraft .if the cg is aft of the torsional axis inertia causes the cg of the wing to lag behind any movement of the axis caused by changes in lift this lag can cause still further changes in incidence and hence lift making the matter worse by having the cg on or forward of the axis now uses the property of inertia to counter the effect .wing mounted engines extending ahead of the wing contribute by moving the wing's cg forward to wing flutter suppression .the risk of flutter increases as ias increases and the speed at which control surface flutter occurs will be decreased with excessive free play or backlash of the control surface the phenomenon occurs earlier exemple 343 I is incorrect, ii is incorrect.I is incorrect, ii is incorrect.

Which of these statements about flutter are correct or incorrect .i aero ?

Question 239-3 : I is correct ii is correct i is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is incorrect

.flutter is a divergent oscillatory motion of a control surface caused by the interaction of aerodynamic forces inertia forces and the stiffness of the structure it is a combination of bending and torsion of the structure . aero elastic coupling affects flutter characteristics . the risk of flutter increases as ias increases . if flutter occurs ias should be reduced . resistance to flutter increases with increasing wing stiffness exemple 347 I is correct, ii is correct.I is correct, ii is correct.

Which of these statements about the gust load factor on an aeroplane are ?

Question 239-4 : I is correct ii is correct i is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is incorrec

.wing area decreases > aspect ratio decreases hence gust load factor decreases .speed increases > gust load factor increases.aspect ratio increases > gust load factor increases.altitude increases > gust load factor decreases due to less dynamic pressure .weight increases > gust load factor decreases due to more mass to accelerate exemple 351 I is correct, ii is correct.I is correct, ii is correct.

Which of these statements about flutter are correct or incorrect .i wing ?

Question 239-5 : I is correct ii is correct i is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is incorrect

.flutter is a dangerous phenomenon encountered in flexible structures subjected to aerodynamic forces as the airspeed increases there may be a point at which the structural damping is insufficient to damp out the motions which are increasing due to aerodynamic energy being added to the airfoil this vibration can cause structural failure and therefore considering flutter characteristics is an essential part of designing an aircraft .if the cg is aft of the torsional axis inertia causes the cg of the wing to lag behind any movement of the axis caused by changes in lift this lag can cause still further changes in incidence and hence lift making the matter worse by having the cg on or forward of the axis now uses the property of inertia to counter the effect .wing mounted engines extending ahead of the wing contribute by moving the wing's cg forward to wing flutter suppression .the risk of flutter increases as ias increases and the speed at which control surface flutter occurs will be decreased with excessive free play or backlash of the control surface the phenomenon occurs earlier exemple 355 I is correct, ii is correct.I is correct, ii is correct.

Which of these statements about flutter are correct or incorrect .i if flutter ?

Question 239-6 : I is correct ii is correct i is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is incorrect

.flutter is a divergent oscillatory motion of a control surface caused by the interaction of aerodynamic forces inertia forces and the stiffness of the structure it is a combination of bending and torsion of the structure . aero elastic coupling affects flutter characteristics . the risk of flutter increases as ias increases . if flutter occurs ias should be reduced . resistance to flutter increases with increasing wing stiffness exemple 359 I is correct, ii is correct.I is correct, ii is correct.

Which of these statements about the gust load factor on an aeroplane are ?

Question 239-7 : I is correct ii is correct i is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is incorrect

. when the slope of the lift versus angle of attack curve decreases the gust load factor decreases means an decrease of angle of attack decreases lift thus when you fly at small angle of attack a gust will have less effect .wing area decreases > aspect ratio decreases hence gust load factor decreases .speed increases > gust load factor increases.aspect ratio increases > gust load factor increases.altitude increases > gust load factor decreases due to less dynamic pressure .weight increases > gust load factor decreases due to more mass to accelerate exemple 363 I is correct, ii is correct.I is correct, ii is correct.

Which of these statements about the gust load factor on an aeroplane are ?

Question 239-8 : I is correct ii is correct i is incorrect ii is incorrect i is incorrect ii is correct i is correct ii is incorrect

.wing area decreases > aspect ratio decreases hence gust load factor decreases .speed increases > gust load factor increases.aspect ratio increases > gust load factor increases.altitude increases > gust load factor decreases due to less dynamic pressure .weight increases > gust load factor decreases due to more mass to accelerate exemple 367 I is correct, ii is correct.I is correct, ii is correct.

Which of these statements concerning flight in turbulence is correct ?

Question 239-9 : Vra is the recommended turbulence penetration air speed vb is the recommended turbulence penetration air speed the load factor in turbulence may fluctuate above and below 1 but will not become negative in severe turbulence speed should be reduced to approximately 1 2 vs

.vra is defined as 'rough airspeed' or 'turbulent air penetration speed' .cs 25 1517 rough air speed vra . a a rough air speed vra for use as the recommended turbulence penetration air speed and a rough air mach number mra for use as the recommended turbulence penetration mach number must be established to ensure that likely speed variation during rough air encounters will not cause the overspeed warning to operate too frequently . b at altitudes where vmo is not limited by mach number in the absence of a rational investigation substantiating the use of other values vra must be less than vmo 35 ktas . c at altitudes where vmo is limited by mach number mra may be chosen to provide an optimum margin between low and high speed buffet boundaries exemple 371 Vra is the recommended turbulence penetration air speed.Vra is the recommended turbulence penetration air speed.

Flutter sensitivity of an aeroplane wing is reduced by ?

Question 239-10 : Locating the engine ahead of the torsional axis of the wing a high speed ias a low torsion stiffness in relation to the bending stiffness empty tanks near the wing tip

.flutter is a dangerous phenomenon encountered in flexible structures subjected to aerodynamic forces as the airspeed increases there may be a point at which the structural damping is insufficient to damp out the motions which are increasing due to aerodynamic energy being added to the airfoil this vibration can cause structural failure and therefore considering flutter characteristics is an essential part of designing an aircraft .if the cg is aft of the torsional axis inertia causes the cg of the wing to lag behind any movement of the axis caused by changes in lift this lag can cause still further changes in incidence and hence lift making the matter worse by having the cg on or forward of the axis now uses the property of inertia to counter the effect .wing mounted engines extending ahead of the wing contribute by moving the wing's cg forward to wing flutter suppression exemple 375 Locating the engine ahead of the torsional axis of the wing.Locating the engine ahead of the torsional axis of the wing.

Flutter of control surfaces is ?

Question 239-11 : A divergent oscillatory motion of a control surface caused by the interaction of aerodynamic forces inertia forces and the stiffness of the structure divergent oscillatory motion of a control surface caused by the interaction of aerodynamic inertia and friction forces the accelerated stall of a wing aileron reversal

.flutter is a divergent oscillatory motion of a control surface caused by the interaction of aerodynamic forces inertia forces and the stiffness of the structure it is a combination of bending and torsion of the structure . aero elastic coupling affects flutter characteristics . the risk of flutter increases as ias increases . if flutter occurs ias should be reduced . resistance to flutter increases with increasing wing stiffness exemple 379 A divergent oscillatory motion of a control surface caused by the interaction of aerodynamic forces, inertia forces and the stiffness of the structure.A divergent oscillatory motion of a control surface caused by the interaction of aerodynamic forces, inertia forces and the stiffness of the structure.

Which statement regarding the manoeuvre and gust load diagram in the clean ?

Question 239-12 : I is correct ii is incorrect i is correct ii is correct i is incorrect ii is incorrect i is incorrect ii is correct

. 2386.the gust load diagram has a symmetrical shape with respect to the n = 1 line for speeds above vb . 2768.the manoeuvre load diagram extends beyond the speed vc exemple 383 I is correct, ii is incorrect.I is correct, ii is incorrect.

The significance of va for jet transport aeroplanes is reduced at high cruising ?

Question 239-13 : Buffet onset limitations normally become limiting the engine has insufficient thrust to reach the limit load factor the elevator deflection is limited to prevent exceeding the limit load factor at high altitudes the bank angle is normally limited to 15° to prevent exceeding the limit load factor

.the manoeuvring speed va expressed as indicated airspeed or mach number of a transport aeroplane depends on aeroplane mass and pressure altitude from the buffet onset boundary chart you will obtain the values of the mach number at which low speed and mach buffet occur at different weights and altitudes va is reduced at high cruising altitudes because buffet onset limitations normally become limiting exemple 387 Buffet onset limitations normally become limiting.Buffet onset limitations normally become limiting.

A fundamental difference between the manoeuvring limit load factor and the gust ?

Question 239-14 : The gust limit load factor can be higher than the manoeuvring limit load factor the gust limit load factor has a fixed value for every transport aeroplane whereas the manoeuvring limit load factor has not the gust limit load factor is independent of the wing's aspect ratio whereas the manoeuvring limit load factor is not the manoeuvring limit load factor is independent of the size of the aeroplane whereas the numerical value of the gust limit load factor is laid down in the regulations

.an aircrafts flight envelope must consider the stength requirements of the structure in still and turbulent conditions .consider an aircraft manoeuvring at it normal limit of 2 5g in still air if the aircraft were to experience a sudden upgust this would increase the angle of attack increase lift and load factor the aircraft must be able to withstand this increase hence the factor the gust limit can be higher than the normal limit exemple 391 The gust limit load factor can be higher than the manoeuvring limit load factor.The gust limit load factor can be higher than the manoeuvring limit load factor.

Which of these statements concerning flight in turbulence is correct ?

Question 239-15 : Vb is the design speed for maximum gust intensity the load factor in turbulence cannot exceed the ultimate load factor the load factor in turbulence may fluctuate above and below 1 but will not become negative in severe turbulence speed should be reduced to approximately 1 2 vs

exemple 395 Vb is the design speed for maximum gust intensity.Vb is the design speed for maximum gust intensity.

From the buffet onset graph of a given jet transport aeroplane it is determined ?

Question 239-16 : The lower mach number increases and the higher mach number decreases the lower mach number decreases and the higher mach number increases both mach numbers decrease both mach numbers increase

.anytime that too great a lift demand is made on the wing whether from too fast an airspeed or from too high an angle of attack near the mmo the high speed buffet will occur .mach buffet occurs as a result of supersonic airflow on the wing stall buffet occurs at angles of attack that produce airflow disturbances burbling over the upper surface of the wing which decreases lift as density altitude increases the angle of attack that is required to produce an airflow disturbance over the top of the wing is reduced until the density altitude is reached where mach buffet and stall buffet converge coffin corner .when this phenomenon is encountered serious consequences may result causing loss of airplane control . 1075.this is purely the aerodynamics factors which define the buffet onset boundary graph .at low speed buffet you are near the conventional stall it occurs at higher speeds with altitude in the other hand high speed buffet occurs at lower speeds with altitude so at some stage the buffets will merge the margin between them called 'coffin corner' is reduced by g force caused by turning and turbulence it means that you have to avoid any manoeuvres that can result in an increase of the load factor exemple 399 The lower mach number increases and the higher mach number decreases.The lower mach number increases and the higher mach number decreases.

For a fixed pitch propeller designed for cruise the angle of attack of each ?

Question 239-17 : Is optimum when the aircraft is in a stabilized cruising flight decreases when the aircraft speed decreases with constant engine rpm is lower in ground run than in flight with constant engine rpm is always positive during idling descent

exemple 403 Is optimum when the aircraft is in a stabilized cruising flight.Is optimum when the aircraft is in a stabilized cruising flight.

Why is a propeller blade twisted from root to tip ?

Question 239-18 : To maintain a constant angle of attack along the whole length of the propeller blade to ensure the angle of attack is greatest at the tip to ensure that the root produces most thrust to ensure that the tip produces most thrust

exemple 407 To maintain a constant angle of attack along the whole length of the propeller blade.To maintain a constant angle of attack along the whole length of the propeller blade.

Constant speed propellers provide a better performance than fixed pitch ?

Question 239-19 : Produce an almost maximum efficiency over a wider speed range have a higher maximum efficiency than a fixed pitch propeller produce a greater maximum thrust than a fixed pitch propeller have more blade surface area than a fixed pitch propeller

exemple 411 Produce an almost maximum efficiency over a wider speed range.Produce an almost maximum efficiency over a wider speed range.

Propeller efficiency may be defined as the ratio between ?

Question 239-20 : Usable power available power of the propeller and shaft power the thrust and the maximum thrust the usable power available power and the maximum power the thermal power of fuel flow and shaft power

exemple 415 Usable (power available) power of the propeller and shaft power.Usable (power available) power of the propeller and shaft power.

An engine failure can result in a windmilling 1 propeller and a feathered 2 ?

Question 239-21 : 1 is larger than 2 1 is equal to 2 2 is larger than 1 impossible to say which one is largest

.a windmilling propeller produces drag roughly equivalent to that of a solid disk of the same diameter as the propeller itself . 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 exemple 419 (1) is larger than (2).(1) is larger than (2).

Increasing the number of propeller blades will ?

Question 239-22 : Increase the maximum absorption of power increase the propeller efficiency increase the noise level at maximum power decrease the torque in the propeller shaft at maximum power

.efficiency is power out compared to power in so you need an aerofoil design that has a good lift/drag ratio a high aspect blade long and narrow will give you low induced drag and so it needs low engine power to overcome drag as propellers operate at big angles of attack to produce thrust a low induced drag will give you a good efficiency .if you look at your light aircraft that is exactly what they have fairly long narrow blades high aspect ratio and good efficiency so you dont need a big engine to drive them .unfortunately they don't move a lot of air backwards so although they are fine if the aircraft weight is low you need more disc solidity the ratio of the total blade area to the disc area if you need more thrust the minute you increase disc solidity with wider blades you are reducing aspect ratio and losing efficiency you will need a stronger engine to overcome the higher drag .power absorbtion is the same as disc solidity in that it reduces efficiency .if you have a powerful engine you are wasting it if you put a high aspect ratio low disc solidity propeller on it because you could drive it at idle you might as well use the power available by increasing the disc solidity and produce more thrust .increasing disc solidity or absorbing more available power will always be contrary to efficiency exemple 423 Increase the maximum absorption of power.Increase the maximum absorption of power.

Gyroscopic precession of the propeller is induced by ?

Question 239-23 : Pitching and yawing increasing rpm and yawing increasing rpm and rolling pitching and rolling

.gyroscopic effect works like this .if an up force is applied to the tail plane causing nose pitch up that would be the same as applying a forward force to the 6 o'clock position on the prop to cause the pitch up if this was a right hand propeller clockwise when viewed from the rear this force would then act at the 9 o'clock postion on the propeller in a forwards movement causing a yaw to the right .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 with a force on the tail causing nose pitch down . /com en/com080 607 png. exemple 427 Pitching and yawing.Pitching and yawing.

Asymmetric propeller blade effect is mainly induced by ?

Question 239-24 : The inclination of the propeller axis to the relative airflow high speed large angles of yaw large angles of climb

exemple 431 The inclination of the propeller axis to the relative airflow.The inclination of the propeller axis to the relative airflow.

Does the pitch angle of a constant speed propeller alter in medium horizontal ?

Question 239-25 : Yes slightly strongly no but only if the pitch is full fine

exemple 435 Yes slightly.Yes slightly.

Which of the following statements about a constant speed propeller is correct ?

Question 239-26 : The blade angle increases with increasing aeroplane speed the propeller system keeps the aeroplane speed constant the rpm decreases with increasing aeroplane speed the selected rpm is kept constant by the manifold pressure

.when it refers to blade angle it refers to the angle between the chord line and the direction of propeller rotation . /com en/com080 636 jpg.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. for a constant speed propeller the propeller system will maintain a constant angle of attack regardless to the speed of the aircraft or the rotational speed it can only be achieved by increasing or decreasing the blade angle .the blade angle of a constant speed propeller increases with increasing aeroplane speed .the blade angle of a constant speed propeller decreases if rpm increases exemple 439 The blade angle increases with increasing aeroplane speed.The blade angle increases with increasing aeroplane speed.

Which is one of the disadvantages of increasing the number of propeller blades ?

Question 239-27 : Decrease propeller efficiency less power can be absorbed by the propeller higher tip speed increased noise

.increased noise no flown a 2 bladed cessna 172 noisy as flown a 3 bladed c172 quieter .less power can be absorbed by the propeller no it's the size that can absorb the power .higher tip speed no more blades = slower rotation speed and then less noise .decrease propeller efficiency too many blades interfere with the airflow for the next blade exemple 443 Decrease propeller efficiency.Decrease propeller efficiency.

If you decrease the propeller pitch during a glide with idle power at constant ?

Question 239-28 : Decrease and the rate of descent will increase increase and the rate of descent will increase decrease and the rate of descent will decrease increase and the rate of descent will decrease

.if you decrease the propeller pitch go from a coarse pitch to a fine pitch you will then have more drag drag to lift ratio is reduced an the rate of descent will increase exemple 447 Decrease and the rate of descent will increase.Decrease and the rate of descent will increase.

If you increase the propeller pitch during a glide with idle power at constant ?

Question 239-29 : Increase and the rate of descent will decrease increase and the rate of descent will increase decrease and the rate of descent will decrease decrease and the rate of descent will increase

.if you increase the propeller pitch go from a fine pitch to a coarse pitch you will then have less drag which means a better lift to drag ratio and at constant ias a lower rate of descent exemple 451 Increase and the rate of descent will decrease.Increase and the rate of descent will decrease.

The angle of attack for a propeller blade is the angle between the blade chord ?

Question 239-30 : Local air speed vector aeroplane heading principal direction of propeller blade direction of propeller axis

exemple 455 Local air speed vector.Local air speed vector.

Given two identical aeroplanes with wing mounted engines one fitted with jet ?

Question 239-31 : More roll tendency for the propeller aeroplane the same roll tendency for both aeroplanes less roll tendency for the propeller aeroplane the same yaw tendency for both aeroplanes regardless of left or right engine failure

.on a jet engines aeroplane you don't have the additional 'critical engine' notion added to your engine failure .explanation .multi engine aeroplanes are subject to p factor just as single engine aeroplanes are the descending propeller blade of each engine will produce greater thrust than the ascending blade when the aeroplane is operated under power and at positive angles of attack the descending propeller blade of the right engine is also a greater distance from the center of gravity and therefore has a longer moment arm than the descending propeller blade of the left engine as a result failure of the left engine will result in the most asymmetrical thrust adverse yaw as the right engine will be providing the remaining thrust . but with counter rotating pairs of engines each pair have propellers rotating in opposite directions there is no yaw tendency in case of engine failure but you will have more roll tendency due to propwash over part of the remaining engine's wing and lack over the wing of the failed engine . /com en/com080 341b jpg.kuznetsov nk 12m turbo prop engine on a tupolev 95 . /com en/com080 341c jpg.antonov 70 exemple 459 More roll tendency for the propeller aeroplane.More roll tendency for the propeller aeroplane.

When the blades of a propeller are in the feathered position ?

Question 239-32 : The drag of the propeller is then minimal the propeller produces an optimal windmilling rpm the windmilling rpm is the maximum the rpm is then just sufficient to lubricate the engine

.a windmilling propeller produces drag roughly equivalent to that of a solid disk of the same diameter as the propeller itself . 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 463 The drag of the propeller is then minimal.The drag of the propeller is then minimal.

Given an aeroplane with a propeller turning clockwise as seen from behind the ?

Question 239-33 : Roll the aeroplane to the left pitch the aeroplane nose down roll the aeroplane to the right pitch the aeroplane nose up

exemple 467 Roll the aeroplane to the left.Roll the aeroplane to the left.

A propeller is turning to the right when viewed from behind the asymmetric ?

Question 239-34 : Yaw the aeroplane to the left roll the aeroplane to the left yaw the aeroplane to the right roll the aeroplane to the right

.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. exemple 471 Yaw the aeroplane to the left.Yaw the aeroplane to the left.

Which definition of propeller parameters is correct ?

Question 239-35 : Geometric pitch is the theoretical distance a propeller blade element would travel in a forward direction during one revolution blade angle is the angle between the blade chord line and the propeller axis angle of attack is the angle between the blade chord line and the propeller vertical plane critical tip velocity is the propeller speed at which flow separation first occurs at some part of the blade

An aeroplane is fitted with a constant speed propeller if the aeroplane speed ?

Question 239-36 : 1 increase 2 remain constant 1 increase 2 increase 1 decrease 2 decrease 1 decrease 2 remain constant

.constant manifold pressure assumes constant power with increasing forward airspeed the blade section angle of attack reduces if the blade angle remains unchanged the rpm would therefore increase to maintain the rpm the blade angle pitch must be increased thus increasing the torque and slowing the propeller to its original set rpm .coarse pitch is large blade angle low rpm and high forward airspeed .fine pitch is small blade angle high rpm and low forward airspeed .blade angle of attack is determined by rpm and tas .the question asks for the condition when all has stabilised again in the 'after' situation manifold pressure and rpm are back to the same as 'before' so torque must also be the same exemple 479 (1) increase (2) remain constant.(1) increase (2) remain constant.

The angle of attack of a fixed pitch propeller blade increases when ?

Question 239-37 : Rpm increases and forward velocity decreases velocity and rpm increase forward velocity increases and rpm decreases velocity and rpm decrease

.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 483 Rpm increases and forward velocity decreases.Rpm increases and forward velocity decreases.

The angle of attack of a propeller blade element is the angle between the blade ?

Question 239-38 : Resultant air speed vector propeller axis propeller plane tas vector

exemple 487 Resultant air speed vector.Resultant air speed vector.

In twin engine aeroplanes with propellers turning clockwise as seen from behind ?

Question 239-39 : The left engine is the critical engine the left engine produces a higher yaw moment if the right engine fails than vice versa the 'minimum control speed' is determined by the failure of the right engine the right engine is the critical engine

.on a jet engines aeroplane you don't have the additional 'critical engine' notion added to your engine failure .explanation .clockwise rotation as viewed from the pilot's seat the critical engine will be the left engine . /com en/com080 341 jpg.multi engine aeroplanes are subject to p factor just as single engine aeroplanes are the descending propeller blade of each engine will produce greater thrust than the ascending blade when the aeroplane is operated under power and at positive angles of attack the descending propeller blade of the right engine is also a greater distance from the center of gravity and therefore has a longer moment arm than the descending propeller blade of the left engine as a result failure of the left engine will result in the most asymmetrical thrust adverse yaw as the right engine will be providing the remaining thrust exemple 491 The left engine is the critical engine.The left engine is the critical engine.

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

Question 239-40 : I is correct ii is correct i is incorrect ii is correct i is incorrect ii is incorrect i is correct ii is incorrect

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 495 I is correct, ii is correctI is correct, ii is correct

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