The critical Mach number of a conventional aerofoil section increases if…

its leading edge radius is decreased.

it is flown at higher angles of attack.

its leading edge radius is decreased.

its thickness to chord ratio is increased.

A jet transport aeroplane is climbing at a constant IAS and constant weight below the tropopause. The operational limit that may be exceeded is:

MMO (Maximum Operating Mach Number)

VMO (Maximum Operating Airspeed)

The coefficient of drag can be defined as the...

ratio of drag pressure to dynamic pressure.

ratio of lift forces to drag forces.

sum of induced drag and parasite drag.

ratio of drag pressure to dynamic pressure.

measure of the efficiency of the aeroplane.

card2brain.ch

You are flying a large jet aircraft equipped with fly-by-wire (FBW) at Mach 0.80 when suddenly the FBW experiences a failure leading to manual pitch trim reversion. Why must the speed now be limited to M 0.77?

At high speed, variation in CG position is no longer compensated by the FBW system.

The pilots are not used to flying large jets manually.

At high speeds, the aerodynamic forces on the control surfaces become too large and could lead to oscillations.

The FBW no longer provides flight envelope protection, and the formation of shock waves at high Mach number can lead to Mach Tuck and control difficulties.

At high speed, variation in CG position is no longer compensated by the FBW system.

The pilots are not used to flying large jets manually.

At high speeds, the aerodynamic forces on the control surfaces become too large and could lead to oscillations.

The FBW no longer provides flight envelope protection, and the formation of shock waves at high Mach number can lead to Mach Tuck and control difficulties.

As an aircraft accelerates through the transonic speed range, it exceeds its Critical Mach number. A normal shock wave forms on the upper surface of the wing, which induces flow separation. This causes...

turbulent air to hit the tail, producing a severe airframe buffet.

up wash over the tail, causing a nose down pitching moment.

downwash over the tail causing a nose up pitching moment.

turbulent air to hit the elevator causing only a light buffet.

turbulent air to hit the tail, producing a severe airframe buffet.

up wash over the tail, causing a nose down pitching moment.

downwash over the tail causing a nose up pitching moment.

turbulent air to hit the elevator causing only a light buffet.

Which type of force tends to decrease the angle of attack on a propeller (fixed or variable pitch)?

Centrifugal force.

Aerodynamic force.

Centripetal force.

No forces reduce the blade angle of attack.

Centrifugal force.

Aerodynamic force.

Centripetal force.

No forces reduce the blade angle of attack.

Consider a manoeuvring-load diagram. Which of the following can you obtain from it?

Best lift to drag ratio speed

Maximum gust load factor

Maximum load factor at stall

Best lift to drag ratio

Best lift to drag ratio speed

Maximum gust load factor

Maximum load factor at stall

Best lift to drag ratio

Located on the underside of a wing's leading edge, Vortilons produce a vortex on the wing's...

upper surface, at cruise angles of attack, to keep the boundary layer attached to the wing.

lower surface, at low angles of attack, to provide improved roll control.

upper surface, at high angles of attack, to reduce the spanwise flow of air.

lower surface, at high angles of attack, to keep the boundary layer attached to the wing.

upper surface, at cruise angles of attack, to keep the boundary layer attached to the wing.

lower surface, at low angles of attack, to provide improved roll control.

upper surface, at high angles of attack, to reduce the spanwise flow of air.

lower surface, at high angles of attack, to keep the boundary layer attached to the wing.

A supercritical wing:

will develop no transonic flow just above MCRIT.

will be free of Mach buffet in the transonic range.

always cruises at MCRIT.

will develop no noticeable shock waves when flying just above MCRIT.

will develop no transonic flow just above MCRIT.

will be free of Mach buffet in the transonic range.

always cruises at MCRIT.

will develop no noticeable shock waves when flying just above MCRIT.

Refer to figure. Arrange the flaps in order from the lowest to highest CL/CD ratio.

3, 1, 2 and 4.

1, 2, 3 and 4.

4, 3, 2 and 1.

4, 2, 3 and 1.

3, 1, 2 and 4.

1, 2, 3 and 4.

4, 3, 2 and 1.

4, 2, 3 and 1.

A modern jet transport aeroplane is cruising at 35000 ft in an area of mountain waves. The cruising speed is at M 0.79 with MMO at M 0.81 when the aeroplane suddenly experiences a positive wind shear. The autothrust is slow at reacting and the aeroplane reaches a speed of M 0.82 before starting to decelerate again. Apart from an overspeed warning, are there any other indications of the overspeed that may be apparent to the pilots?

the aeroplane is buffeting and a significant pitch-down moment suddenly develops, requiring an immediate corrective action to avoid entering a dive.

with the feet on the ground, a slight vibration is felt through the fuselage structure, otherwise the aeroplane observes normal behaviour.

unusually high levels of ambient wind noise followed by severe buffeting requiring a pitch-up input to ensure a rapid deceleration to a speed below MMO.

strong shock waves will be forming, creating separation of the boundary layer, causing a significant buffet as the aeroplane enters a high-speed shock stall.

the aeroplane is buffeting and a significant pitch-down moment suddenly develops, requiring an immediate corrective action to avoid entering a dive.

with the feet on the ground, a slight vibration is felt through the fuselage structure, otherwise the aeroplane observes normal behaviour.

unusually high levels of ambient wind noise followed by severe buffeting requiring a pitch-up input to ensure a rapid deceleration to a speed below MMO.

strong shock waves will be forming, creating separation of the boundary layer, causing a significant buffet as the aeroplane enters a high-speed shock stall.

In addition to ailerons, spoilers might be used at the same time to assist in lateral control. When doing so, how will the spoilers behave?

Down-going wing spoilers fully rise with aileron input, disturbing the airflow over the wing, reducing lift, and creating a roll moment.

Down-going wing spoilers rise proportionally to aileron input, disturbing the airflow over the wing, reducing lift, and creating a roll moment.

Up-going wing spoilers fully rise with aileron input, increasing total drag, reducing lift, and creating a roll moment.

Up-going wing spoilers rise proportionally to aileron input, locally increasing drag, assisting to counteracting adverse yaw.

Down-going wing spoilers fully rise with aileron input, disturbing the airflow over the wing, reducing lift, and creating a roll moment.

Down-going wing spoilers rise proportionally to aileron input, disturbing the airflow over the wing, reducing lift, and creating a roll moment.

Up-going wing spoilers fully rise with aileron input, increasing total drag, reducing lift, and creating a roll moment.

Up-going wing spoilers rise proportionally to aileron input, locally increasing drag, assisting to counteracting adverse yaw.

What is correct about a slat? A deployed slat will...

Increase the boundary layer energy and increase the suction peak on the fixed part of the wing, so that the stall is postponed to higher angles of attack.

Increase the boundary layer energy, move the suction peak from the fixed part of the wing to the slat, so that the stall is postponed to higher angles of attack.

Decrease the boundary layer energy and decrease the suction peak on the slat, so that CLMAX is reached at lower angles of attack.

Increase the camber of the aerofoil and increase the effective angle of attack, so that CLMAX is reached at higher angles of attack.

Increase the boundary layer energy and increase the suction peak on the fixed part of the wing, so that the stall is postponed to higher angles of attack.

Increase the boundary layer energy, move the suction peak from the fixed part of the wing to the slat, so that the stall is postponed to higher angles of attack.

Decrease the boundary layer energy and decrease the suction peak on the slat, so that CLMAX is reached at lower angles of attack.

Increase the camber of the aerofoil and increase the effective angle of attack, so that CLMAX is reached at higher angles of attack.

When an aircraft with stabiliser trim is trimmed "nose up", what is the position of the stabiliser and elevator compared to the horizontal axis of the aircraft? Consider the stabiliser movement to be that occurring at its trailing edge. The stabiliser will be...

deflected up with the elevator down.

parallel to the horizontal axis, with the elevator in line with it.

deflected down with the elevator in line with it.

deflected up with the elevator in line with it.

deflected up with the elevator down.

parallel to the horizontal axis, with the elevator in line with it.

deflected down with the elevator in line with it.

deflected up with the elevator in line with it.

In asymmetric flight, rudder is used to stop yaw and ailerons to bank towards the live engine. The bank angle must be limited to prevent...

the possibility of a fin stall or structural failure of the vertical tailplane.

increasing the side force on the fin from sideslip.

excessive loss of the vertical component of lift.

the rudder from losing authority to stop the yaw.

the possibility of a fin stall or structural failure of the vertical tailplane.

increasing the side force on the fin from sideslip.

excessive loss of the vertical component of lift.

the rudder from losing authority to stop the yaw.

Choose the correct statement:

A slightly unstable short period oscillation is no problem for an aeroplane.

When the phugoid is slightly unstable, an aeroplane becomes uncontrollable.

The phugoid should always be heavily damped.

The short period oscillation should always be heavily damped.

A slightly unstable short period oscillation is no problem for an aeroplane.

When the phugoid is slightly unstable, an aeroplane becomes uncontrollable.

The phugoid should always be heavily damped.

The short period oscillation should always be heavily damped.

An aircraft climbs to FL210 with a CAS of 150 kt. Once reaching FL210 it accelerates to cruise speed whilst maintaining the same heading. What happens to the coefficient of lift?

Decreases due to fuel burnt.

Increases.

Remains the same.

Decreases due to the pilot or autopilot reduce angle of attack.

Decreases due to fuel burnt.

Increases.

Remains the same.

Decreases due to the pilot or autopilot reduce angle of attack.

A low wing aircraft entering the ground effect during the landing phase will experience...

an increase in wing-tip vortices.

a reduction in interference drag and tendency to float.

an increase in induced drag.

a nose-down pitching moment

an increase in wing-tip vortices.

a reduction in interference drag and tendency to float.

an increase in induced drag.

a nose-down pitching moment

What is true about a too high solidity due to a too high number of blades?

Airflow becomes less undisruptive for successive blades.

Airflow becomes more disruptive for successive blades.

Due to the increased speed, the airflow may become supersonic forming shockwaves at the spinner.

Due to the increased speed, the airflow may become supersonic forming shockwaves at the tips.

Airflow becomes less undisruptive for successive blades.

Airflow becomes more disruptive for successive blades.

Due to the increased speed, the airflow may become supersonic forming shockwaves at the spinner.

Due to the increased speed, the airflow may become supersonic forming shockwaves at the tips.

A large jet aircraft is designed to be operated with a positive longitudinal stability and is equipped with a Fly-By-Wire (FBW) system. Prior to each flight, the pilots input the aircraft mass and CG location into the Flight Management System (FMS). The aircraft's FMS then informs the FBW system of this data, allowing for the correct control forces and limitations to be used, giving flight envelope protection and ensuring stability is maintained. Consider what will happen to the aircraft's high altitude handling characteristics if the pilot inputs the INCORRECT CG position into the FMS, located forward of the actual CG position. Which of the following statements is correct?

The actual longitudinal stability is lower than calculated by the FBW system, and the system may allow for control surface deflections that result in instability.

Due to the design criteria applied, the longitudinal stability of the aircraft is always ensured, irrespective of the location of the CG.

The pitch rates commanded by the FBW system are lower at higher altitudes compared to the pitch rates required to ensure that the longitudinal stability remains positive.

The aircraft consumes more fuel than expected during the cruise phase of the flight, as the FBW system deflects the horizontal stabiliser more to counteract the error of the pilot.

The actual longitudinal stability is lower than calculated by the FBW system, and the system may allow for control surface deflections that result in instability.

Due to the design criteria applied, the longitudinal stability of the aircraft is always ensured, irrespective of the location of the CG.

The pitch rates commanded by the FBW system are lower at higher altitudes compared to the pitch rates required to ensure that the longitudinal stability remains positive.

The aircraft consumes more fuel than expected during the cruise phase of the flight, as the FBW system deflects the horizontal stabiliser more to counteract the error of the pilot.

Excluding constants, the coefficient of induced drag (CDi) is the ratio of:

CL and b (wingspan).

CL² and AR (aspect ratio).

CL and CD.

CL and AR (aspect ratio).

CL and b (wingspan).

CL² and AR (aspect ratio).

CL and CD.

CL and AR (aspect ratio).

Which statement is true regarding a reduction in induced drag?

Decrease downwash and increase induced angle of attack.

Decrease upwash and decrease induced angle of attack.

Increase downwash and decrease the induced angle of attack.

Increase upwash and decrease induced angle of attack.

Decrease downwash and increase induced angle of attack.

Decrease upwash and decrease induced angle of attack.

Increase downwash and decrease the induced angle of attack.

Increase upwash and decrease induced angle of attack.

Refer to figure. The tab in the figure represents...

an anti-balance tab.

a balance tab.

a servo tab.

a trim tab.

an anti-balance tab.

a balance tab.

a servo tab.

a trim tab.

If flying at the speed labelled 2, what will happen if the pilot applies full and sudden nose-up elevator input?

The aircraft will experience an accelerated stall at a load factor greater than 2g.

The aircraft will exceed the positive structural limit load factor before stalling.

The aircraft can safely reach the manoeuvring limit load factor without stalling.

The aircraft will suffer immediate structural damage.

Commandes clavier:

= tourner,

= avant/arrière,

= faire défiler

The aircraft will experience an accelerated stall at a load factor greater than 2g.

The aircraft will exceed the positive structural limit load factor before stalling.

The aircraft can safely reach the manoeuvring limit load factor without stalling.

The aircraft will suffer immediate structural damage.

A Cessna Skyhawk has a VA of 123 kt when its mass is 2 300 lbs. Determine its VA at a mass of 1 900 lbs.

112 kt

102 kt

149 kt

135 kt

Commandes clavier:

= tourner,

= avant/arrière,

= faire défiler

112 kt

102 kt

149 kt

135 kt

What happens to the blade angle and RPM of a constant speed propeller when the aeroplane wing's angle of attack decreases in level flight?

Both the blade angle and the RPM increase.

Blade angle remains constant, whilst the RPM increases.

The RPM decreases and the blade angle increases.

The blade angle increases and the RPM remains constant.

Commandes clavier:

= tourner,

= avant/arrière,

= faire défiler

Both the blade angle and the RPM increase.

Blade angle remains constant, whilst the RPM increases.

The RPM decreases and the blade angle increases.

The blade angle increases and the RPM remains constant.

Which of the following situations describes the most favourable situation in case of an engine failure on a twin engine aeroplane?

Failure of the left engine if both engines are rotating in the same direction.

Failure of the right engine if both engines are counter rotating outwards.

Failure of the left engine if both engines are counter rotating outwards.

Failure of the right engine if both engines are counter rotating inwards.

Commandes clavier:

= tourner,

= avant/arrière,

= faire défiler

Failure of the left engine if both engines are rotating in the same direction.

Failure of the right engine if both engines are counter rotating outwards.

Failure of the left engine if both engines are counter rotating outwards.

Failure of the right engine if both engines are counter rotating inwards.

The attached figure shows an aeroplane in cruise flight suffering an engine failure with significant damage. The aircraft speed is reducing, and the pilot needs to increase the rudder input to counteract the asymmetric yawing moment. Why is this?

The right sideslip is causing the vertical stabiliser to stall.

As airspeed reduces, the live engine produces a stronger yawing moment.

The left sideslip is causing the vertical stabiliser to stall.

Rudder effectiveness is reduced due to a higher fin AoA at low speeds.

Commandes clavier:

= tourner,

= avant/arrière,

= faire défiler

The right sideslip is causing the vertical stabiliser to stall.

As airspeed reduces, the live engine produces a stronger yawing moment.

The left sideslip is causing the vertical stabiliser to stall.

Rudder effectiveness is reduced due to a higher fin AoA at low speeds.

In a sideslip condition, increasing the sweep angle of a vertical stabiliser has what effect on static directional stability and the fin's critical angle of attack?

(1) positive; (2) decreases

(1) negative; (2) decreases

(1) negative; (2) increases

(1) positive; (2) increases

Commandes clavier:

= tourner,

= avant/arrière,

= faire défiler

(1) positive; (2) decreases

(1) negative; (2) decreases

(1) negative; (2) increases

(1) positive; (2) increases

For any propeller:

the force contributing to propeller torque is perpendicular to the propeller plane of rotation.

thrust is the component of the total aerodynamic force on the propeller parallel to the rotational axis.

thrust is the component of the total aerodynamic force on the propeller in the plane of rotation.

the total aerodynamic force on a blade element may be resolved into two components, torque and lift.

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

the force contributing to propeller torque is perpendicular to the propeller plane of rotation.

thrust is the component of the total aerodynamic force on the propeller parallel to the rotational axis.

thrust is the component of the total aerodynamic force on the propeller in the plane of rotation.

the total aerodynamic force on a blade element may be resolved into two components, torque and lift.

You are the pilot flying of a single engine tailwheel aircraft with a strong propeller turning right on a wet grass runway. During acceleration for take-off, you are forced to use considerable right rudder to keep the aircraft straight. This is because during the early part of the take-off run the propeller produces...

gyroscopic precession before the tail is lifted, and slipstream effect after the tail is lifted.

slipstream effect before the tail is lifted, and asymmetric blade effect after the tail is lifted.

gyroscopic precession as the tail is lifted, and asymmetric blade effect only after the tail is lifted.

asymmetric blade effect before the tail is lifted, and gyroscopic precession as the tail is lifted.

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

gyroscopic precession before the tail is lifted, and slipstream effect after the tail is lifted.

slipstream effect before the tail is lifted, and asymmetric blade effect after the tail is lifted.

gyroscopic precession as the tail is lifted, and asymmetric blade effect only after the tail is lifted.

asymmetric blade effect before the tail is lifted, and gyroscopic precession as the tail is lifted.

In a steady glide, the rate of descent can be determined by multiplying (1) _____ with the (2) _____ of the descent angle.

(1) TAS; (2) Cos

(1) TAS; (2) Sin

(1) IAS; (2) Cos

(1) IAS; (2) Sin

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

(1) TAS; (2) Cos

(1) TAS; (2) Sin

(1) IAS; (2) Cos

(1) IAS; (2) Sin

The boundary layer of a wing is:

created by the normal shock wave at transonic speeds.

a turbulent flow around the wing.

a layer on the wing in which the stream velocity is lower than the free stream velocity.

caused by suction on the upper wing surface.

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

created by the normal shock wave at transonic speeds.

a turbulent flow around the wing.

a layer on the wing in which the stream velocity is lower than the free stream velocity.

caused by suction on the upper wing surface.

Consider an aerofoil section. The relative thickness is the ratio of...

maximum thickness to maximum camber.

maximum thickness to chord length.

average thickness to chord length.

average thickness to medium camber-line length.

maximum thickness to maximum camber.

maximum thickness to chord length.

average thickness to chord length.

average thickness to medium camber-line length.

An aircraft has been parked outside overnight, in freezing conditions. The crew decides to depart WITHOUT having the airframe de-iced/anti-iced. What could be the principal danger during take-off?

Uncommanded roll due to frozen deposits on the wings, which increase CLMAX.

Loss of control due to frozen deposits on the wings, which reduce CLMAX.

A lower stall speed due to wing contamination and increased drag.

A higher stall speed due to wing contamination and reduced drag.

Uncommanded roll due to frozen deposits on the wings, which increase CLMAX.

Loss of control due to frozen deposits on the wings, which reduce CLMAX.

A lower stall speed due to wing contamination and increased drag.

A higher stall speed due to wing contamination and reduced drag.

Refer to figure. On approach, the aircraft's ECAM display shows "Flaps Locked", but with slats working normally. What will the pilots experience in this case, compared to landing with a clean wing.

Greater lift production but a lower AoA at CLMAX.

An increased landing distance, as the pilot must use a higher approach speed.

The aircraft will behave exactly like a clean wing but with more drag.

A higher AoA and increased drag, leading to an increased risk of tailstrike but a shorter landing distance.

Greater lift production but a lower AoA at CLMAX.

An increased landing distance, as the pilot must use a higher approach speed.

The aircraft will behave exactly like a clean wing but with more drag.

A higher AoA and increased drag, leading to an increased risk of tailstrike but a shorter landing distance.

On approach you are flying at VMD, but decide to increase your speed slightly. You are now flying in the so-called speed (1) _____ region and the total drag has (2) _____.

(1) unstable; (2) decreased

(1) unstable; (2) increased

(1) stable; (2) decreased

(1) stable; (2) increased

(1) unstable; (2) decreased

(1) unstable; (2) increased

(1) stable; (2) decreased

(1) stable; (2) increased

A flight instructor is teaching a student of a multi-engine piston airplane the practice of an engine failure. What is the most favourable configuration during the first engine failure exercise?

An airplane mass of 3 800 lbs so that the resultant yaw from the engine failure is minimized.

An airplane mass of 4 400 lbs so that the resultant yaw from the engine failure is minimized.

An airplane mass of 3 800 lbs so that the rudder has greater effectiveness.

An airplane mass of 4 400 lbs so that the rudder has greater effectiveness.

An airplane mass of 3 800 lbs so that the resultant yaw from the engine failure is minimized.

An airplane mass of 4 400 lbs so that the resultant yaw from the engine failure is minimized.

An airplane mass of 3 800 lbs so that the rudder has greater effectiveness.

An airplane mass of 4 400 lbs so that the rudder has greater effectiveness.

When speed is increased in straight and level flight on a positively cambered aerofoil, what happens to the: 1. centre of pressure and 2. the magnitude of the total lift force?

1 moves aft and 2 remains constant.

1 moves forward and 2 decreases.

1 moves forward and 2 remains constant.

1 moves aft and 2 increases.

1 moves aft and 2 remains constant.

1 moves forward and 2 decreases.

1 moves forward and 2 remains constant.

1 moves aft and 2 increases.

During a demonstration of the effect of controls, the pilot manoeuvres the aeroplane applying aileron input only. This control input will make the aeroplane roll...

and sideslip towards the lower wing due to the sideways components of lift, and gravity and the sideslip angle will increase with the increasing bank angle.

and skid towards the higher wing due to the inertia of the aeroplane, and the amount of skid is dependent on the relationship between the bank angle and speed.

towards the wing with the upward deflecting aileron, and the rolling motion will stop at a bank angle that is directly related to the stick position.

towards the wing with the downward deflecting aileron, and the roll rate will be proportional to the movement of the control column.

and sideslip towards the lower wing due to the sideways components of lift, and gravity and the sideslip angle will increase with the increasing bank angle.

and skid towards the higher wing due to the inertia of the aeroplane, and the amount of skid is dependent on the relationship between the bank angle and speed.

towards the wing with the upward deflecting aileron, and the rolling motion will stop at a bank angle that is directly related to the stick position.

towards the wing with the downward deflecting aileron, and the roll rate will be proportional to the movement of the control column.

Moving the CG of an aircraft forward will have what effect on the stall speed, VS?

None, the CG position has NO influence of VS.

VS decreases, due to an increase in critical angle of attack.

Equivalent to the effect of an increase in mass.

Equivalent to the effect of a decrease in mass.

None, the CG position has NO influence of VS.

VS decreases, due to an increase in critical angle of attack.

Equivalent to the effect of an increase in mass.

Equivalent to the effect of a decrease in mass.

Considering the effect of wing downwash on the direction of the airflow approaching the tailplane, when flaps are extended the tailplane’s negative angle of attack...

increases, increasing the tailplane’s effectiveness.

increases, decreasing the tailplane’s effectiveness.

decreases, increasing the tailplane’s effectiveness.

decreases, decreasing the tailplane’s effectiveness.

increases, increasing the tailplane’s effectiveness.

increases, decreasing the tailplane’s effectiveness.

decreases, increasing the tailplane’s effectiveness.

decreases, decreasing the tailplane’s effectiveness.