Principles of Flight Questions The angle of attack (aerodynamic angle of incidence) of an aerofoil is the angle between the: 1 bottom surface and the horizontal bottom surface and the relative airflow. bottom surface and the chord line. chord line and the relative undisturbed airflow. In a stationary subsonic streamline flow pattern, if the streamlines converge, in this part of the pattern, the static pressure (I) will ...and the velocity (II) will ...: 2 (I) decrease, (II) increase. (I) increase, (II) increase. (I) increase, (II) decrease. (I) increase, (II) decrease. The SI units of air density (I) and force (II) are: 3 (I) kg / m3, (II) N. (I) kg / m², (II) kg. (I) N / m3, (II) N. (I) N / kg, (II) kg. The units of wing loading (I) W / S and (II) dynamic pressure q are: 4 (I) kg / m, (II) N / m². (I) N / m, (II) kg. (I) N / m3, (II) kg / m². (I) N / m², (II) N / m². Which formula or equation describes the relationship between force (F), acceleration (a) and mass (m)? 5 m=F.a a=F. m F=m / a F=m. a Static pressure acts: 6 only in direction of the flow. only perpendicular to the direction of the flow. in all directions. Página 1 de 80 Principles of Flight
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Principles of Flight
Questions
The angle of attack (aerodynamic angle of incidence) of an aerofoil is the angle between the:1
bottom surface and the horizontal
bottom surface and the relative airflow.
bottom surface and the chord line.
chord line and the relative undisturbed airflow.
In a stationary subsonic streamline flow pattern, if the streamlines converge, in this part of
the pattern, the static pressure (I) will ...and the velocity (II) will ...:
2
(I) decrease, (II) increase.
(I) increase, (II) increase.
(I) increase, (II) decrease.
(I) increase, (II) decrease.
The SI units of air density (I) and force (II) are:3
(I) kg / m3, (II) N.
(I) kg / m², (II) kg.
(I) N / m3, (II) N.
(I) N / kg, (II) kg.
The units of wing loading (I) W / S and (II) dynamic pressure q are:4
(I) kg / m, (II) N / m².
(I) N / m, (II) kg.
(I) N / m3, (II) kg / m².
(I) N / m², (II) N / m².
Which formula or equation describes the relationship between force (F), acceleration (a)
and mass (m)?
5
m=F.a
a=F. m
F=m / a
F=m. a
Static pressure acts:6
only in direction of the flow.
only perpendicular to the direction of the flow.
in all directions.
Página 1 de 80Principles of Flight
Questions
only in the direction of the total pressure.
Lift is generated when:7
the flow direction of a certain mass of air is changed.
a certain mass of air is accelerated in its flow direction.
a symmetrical aerofoil is placed in a high velocity air stream at zero angle of attack.
a certain mass of air is retarded.
Consider the steady flow through a stream tube where the velocity of the stream is V. An
increase in temperature of the flow at a constant value of V will:
8
decrease the mass flow.
increase the mass flow when the tube is divergent in the direction of the flow.
increase the mass flow.
not affect the mass flow.
Which one of the following statements about Bernoulli's theorem is correct?9
The dynamic pressure increases as static pressure decreases.
The dynamic pressure decreases as static pressure decreases.
The total pressure is zero when the velocity of the stream is zero.
The dynamic pressure is maximum in the stagnation point.
If in a two-dimensional incompressible and subsonic flow, the streamlines converge the
static pressure in the flow will:
10
increase.
not change.
decrease.
increase initially, then decrease.
Bernoulli's equation can be written as:
(pt= total pressure, ps = static pressure and q=dynamic pressure)
11
pt = ps / q
pt = ps + q
pt = ps - q
pt = q - ps
Which of the following statements about boundary layers is correct?12
The turbulent boundary layer will separate more easily than the laminar boundary layer.
The turbulent boundary layer gives a lower skin friction than the laminar boundary layer.
The turbulent boundary layer has more kinetic energy than the laminar boundary layer.
The turbulent boundary layer is thinner than the laminar boundary layer.
Página 2 de 80Principles of Flight
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Where on the surface of a typical aerofoil will flow separation normally start at high angles
of attack?
13
upper side trailing edge.
upper side leading edge.
lower side trailing edge.
lower side leading edge.
On an asymmetrical, single curve aerofoil, in subsonic airflow, at low angle of attack, when
the angle of attack is increased, the centre of pressure will (assume a conventional transport
aeroplane):
14
move forward.
move aft.
remain matching the airfoil aerodynamic centre.
remain unaffected.
The Cl - alpha curve of a positive cambered aerofoil intersects with the vertical axis of the
Cl - alpha graph:
15
nowhere.
below the origin.
in the origin.
above the origin.
The angle of attack of a two dimensional wing section is the angle between:16
the chord line of the aerofoil and the fuselage centreline.
the fuselage centreline and the free stream direction.
the chord line and the camber line of the aerofoil.
the chord line of the aerofoil and the free stream direction.
The angle between the airflow (relative wind) and the chord line of an aerofoil is:17
glide path angle.
climb path angle.
angle of attack.
same as the angle between chord line and fuselage axis.
The angle between the aeroplane longitudinal axis and the chord line is the:18
angle of incidence.
glide path angle.
angle of attack.
climb path angle.
Página 3 de 80Principles of Flight
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With increasing angle of attack, the stagnation point will move (I) ...and the point of lowest
pressure will move (II) ...Respectively (I) and (II) are:
19
(I) up, (II) aft.
(I) down, (II) aft.
(I) down, (II) forward.
(I) up, (II) forward.
The aerodynamic centre of the wing is the point, where:20
the pitching moment coefficient does not vary with angle of attack.
changes of lift due to variations in angle of attack are constant.
aerodynamic forces are constant.
the aeroplane's lateral axis intersects with the centre of gravity.
"Flutter" may be caused by:21
low airspeed aerodynamic wing stall.
roll control reversal.
distortion by bending and torsion of the structure causing increasing vibration in the resonance frequency.
high airspeed aerodynamic wing stall.
On a swept wing aeroplane at low airspeed, the "pitch up" phenomenon:22
is caused by boundary layer fences mounted on the wings.
is caused by wingtip stall.
never occurs, since a swept wing is a "remedy" to pitch up.
is caused by extension of trailing edge lift augmentation devices.
Low speed pitch up is caused by the:23
Mach trim system.
wing tip vortex.
spanwise flow on a swept back wing.
spanwise flow on a swept forward wing.
The lift of an aeroplane of weight W in a constant linear climb with a climb angle (gamma)
is approximately:
24
Wcos.gamma.
W(1-sin.gamma).
W(1-tan.gamma).
W/cos.gamma.
Página 4 de 80Principles of Flight
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The lift coefficient (CL) of an aeroplane in steady horizontal flight is 0.42. An increase in
angle of attack of 1 degree increases CL by 0.1. A vertical up gust instantly changes the
angle of attack by 3 degrees. The load factor will be:
25
0.74
1.49
1.71
2.49
The aeroplane drag in straight and level flight is lowest when the:26
induced drag is lowest.
parasite drag is equal to the induced drag.
parasite drag equals twice the induced drag.
induced drag is equal to zero.
Considering a positive cambered aerofoil, the pitching moment when Cl=0 is:27
positive (nose-up).
infinite
negative (nose-down).
equal to zero.
On a un-swept wing, when the aerofoil is accelerated from subsonic to supersonic speeds,
the aerodynamic centre:
28
shifts from 25% to about 50% of the aerofoil chord.
shifts aft by about 10%.
remains unchanged.
slightly shifts forward.
On a symmetrical aerofoil, the pitching moment for which Cl=0 is:29
zero
equal to the moment coefficient for stabilized angle of attack.
positive (pitch-up)
negative (pitch-down)
The lift coefficient (CL) of an aeroplane in steady horizontal flight is 0.4. An increase in
angle of attack of 1 degree will increase CL by 0.09. A vertical up gust instantly changes the
angle of attack by 5 degrees. The load factor will be:
30
2.0
3.18
1.09
Página 5 de 80Principles of Flight
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2.13
An aeroplane maintains straight and level flight while the IAS is doubled. The change in lift
coefficient will be:
31
x 2.0
x 0.5
x 4.0
x 0.25
The effect of a positive wing sweep on static directional stability is as follows:32
No effect
Destabilizing dihedral effect
Stabilizing effect
Negative dihedral effect
The effect on static stability of an aeroplane with a high wing as compared to a low wing is:33
a positive dihedral effect
a negative dihedral effect
no effect as it is only used to improve aeroplane loading
zero dihedral effect
The lift coefficient (CL) of an aeroplane in steady horizontal flight is 0.35. An increase in
angle of attack of 1 degree would increase CL by 0.079. If a vertical gust instantly changes
the angle of attack by 2 degrees, the load factor will be:
34
0.9
0.45
1.45
1.9
When an aeroplane is flying at an airspeed which is 1.3 times its basic stalling speed, the
coefficient of lift as a percentage of the maximum lift coefficient (CLmax) would be:
35
59%.
130%.
169%.
77%.
The lift formula is:36
L= W
L= CL 2 RHO V² S
L= CL 1/2 RHO V² S
Página 6 de 80Principles of Flight
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L= n W
An aeroplane is in a level turn, at a constant TAS of 300 kt, and a bank angle of 45°. Its
turning radius is:
(given: g= 10 m/s²)
37
3354 metres.
2381 metres.
4743 metres.
9000 metres.
Which one of the following statements about the lift-to-drag ratio in straight and level flight
is correct?
38
The lift/drag ratio always increases as the lift decreases.
The highest value of the lift/drag ratio is reached when the lift is equal to the aircraft weight.
At the highest value of the lift/drag ratio the total drag is lowest.
The highest value of the lift/drag ratio is reached when the lift is zero.
Drag is in the direction of - and lift is perpendicular to the:39
relative wind/airflow.
chord line.
horizon.
longitudinal axis.
If the nose of an aeroplane yaws left, this causes:40
a decrease in relative airspeed on the right wing.
an increase in lift on the left wing.
a roll to the left.
a roll to the right.
At an aeroplane's minimum drag speed, what is the ratio between induced drag Di and
parasite drag Dp? Di/Dp=
41
1/2
1/1
It varies between aeroplane types.
2/1
The correct drag formula is:42
D= CD 1/2 1/RHO V² S
D= CD 1/2 RHO V S
D= CD 1/2 RHO V² S
Página 7 de 80Principles of Flight
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D= CD 2 RHO V² S
The value of the parasite drag in straight and level flight at constant weight varies linearly
with the:
43
square of the speed.
speed.
angle of attack.
square of the angle of attack.
An aeroplane accelerates from 80 kt to 160 kt at a load factor equal to 1. The induced drag
coefficient (i) and the induced drag (ii) alter with the following factors:
44
(i) 1/16 (ii) 1/4
(i) 1/4 (ii) 2
(i) 1/2 (ii) 1/16
(i) 4 (ii) 1/2
What is the effect of high aspect ratio of an aeroplane's wing on induced drag?45
It is unaffected because there is no relation between aspect ratio and induced drag.
It is increased because high aspect ratio has greater frontal area.
It is reduced because the effect of wing-tip vortices is reduced.
It is increased because high aspect ratio produces greater downwash.
In what way do (1) induced drag and (2) parasite drag alter with increasing speed in
straight and level flight ?
46
(1) decreases and (2) increases.
(1) increases and (2) increases.
(1) decreases and (2) decreases.
(1) increases and (2) decreases.
Which of the following wing planforms produces the lowest induced drag? (all other
relevant factors constant)
47
Rectangular.
Tapered.
Elliptical.
Circular.
If flaps are deployed at constant IAS in straight and level flight, the magnitude of tip
vortices will eventually: (flap span less than wing span)
48
decrease.
increase.
Página 8 de 80Principles of Flight
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remain the same.
increase or decrease, depending on the initial angle of attack.
The value of the induced drag of an aeroplane in straight and level flight at constant weight
varies linearly with:
49
V²
V
1/V²
1/V
Induced drag at constant IAS is affected by:50
aeroplane weight.
aeroplane wing location.
angle between wing chord and fuselage centre line.
engine thrust.
Which of the following will reduce induced drag?51
Low aspect ratio.
Flying at high angles of attack.
Elliptical lift distribution.
Extending the flaps.
Induced drag is created by the:52
propeller wash blowing across the wing.
spanwise flow pattern resulting in the tip vortices.
interference of the air stream between wing and fuselage.
separation of the boundary layer over the wing.
Vortex generators:53
take kinetic energy out of the boundary layer to reduce separation.
reduce the spanwise flow on swept wing.
transfer energy from the free airflow into the boundary layer.
change the turbulent boundary layer into a laminar boundary layer.
How does the total drag vary as speed is increased from stalling speed (VS) to maximum
IAS (VNE) in a straight and level flight at constant weight?
54
Decreasing, then increasing.
Decreasing.
Increasing.
Página 9 de 80Principles of Flight
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Increasing, then decreasing.
A boundary layer fence on a swept wing will:55
improve the high speed characteristics.
increase the critical Mach Number.
improve the low speed characteristics.
improve the lift coefficient of the trailing edge flap.
In order to perform a steady level turn at constant speed in an aeroplane, the pilot must:56
increase angle of attack and keep thrust/power unchanged.
increase thrust/power and angle of attack.
increase thrust/power and keep angle of attack unchanged.
increase thrust/power and decrease angle of attack.
When an aeroplane with the centre of gravity forward of the centre of pressure of the
combined wing / fuselage is in straight and level flight, the vertical load on the tailplane will
be:
57
downwards because it is always negative regardless of the position of the centre of gravity.
zero because in steady flight all loads are in equilibrium.
downwards.
upwards.
In a twin engine jet aeroplane (engines mounted below the low wings) the thrust is suddenly
increased. Which elevator deflection will be required to maintain the pitching moment zero ?
58
Down.
Up.
No elevator movement will required because the thrust line of the engines remains unchanged.
It depends on the position of the centre of gravity.
In which situation would the wing lift of an aeroplane in straight and level flight have the
highest value ?
59
Forward centre of gravity and idle thrust.
Aft centre of gravity and idle thrust.
Forward centre of gravity and take-off thrust.
Aft centre of gravity and take-off thrust.
An aeroplane, with a C.G. location behind the centre of pressure of the wing can only
maintain a straight and level flight when the horizontal tail loading is:
60
downwards.
upwards or downwards depending on elevator deflection.
Página 10 de 80Principles of Flight
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zero.
upwards.
The centre of gravity moving aft will:61
decrease the elevator up effectiveness.
not affect the elevator up or down effectiveness.
increase or decrease the elevator up effectiveness, depending on wing location.
increase the elevator up effectiveness.
If the total sum of moments about one of its axes is not zero, an aeroplane would:62
be difficult to control.
fly a path with a constant curvature.
experience an angular acceleration about that axis.
not be affected because the situation is normal.
During landing of a low-winged jet aeroplane, the greatest elevator up deflection is
normally required when the flaps are:
63
fully down and the cg is fully forward.
up and the cg is fully forward.
fully down and the cg is fully aft.
up and the cg is fully aft.
Rotation about the lateral axis is called:64
rolling.
yawing.
pitching.
slipping.
Rolling is the rotation of the aeroplane about the:65
longitudinal axis.
vertical axis.
lateral axis.
wing axis.
An aeroplane has static directional stability; in a side-slip to the right, initially the:66
right wing tends to go down.
nose of the aeroplane will remain in the same direction.
nose of the aeroplane tends to move to the right.
nose of the aeroplane tends to move to the left.
Página 11 de 80Principles of Flight
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The cg of an aeroplane is in a fixed position forward of the neutral point. Speed changes
cause a departure from the trimmed position. Which of the following statements about the
stick force stability is correct?
67
Stick force stability is not affected by trim.
An increase of 10kt from the trimmed position at low speed has more effect on the stick force than an increase of 10kt from the trimmed position at high speed.
Increase of speed generates pull forces.
Aeroplane nose up trim decreases the stick force stability.
The (1) stick force stability and the (2) manoeuvre stability are positively affected by:68
(1) aft C.G. movement (2) aft CG. movement.
(1) trimming the aeroplane nose up (2) trimming the aeroplane nose up.
(1) forward C.G. movement (2) forward CG. movement.
(1) forward C.G. movement (2) trimming the aeroplane nose up.
The value of the manoeuvre stability of an aeroplane is 150 N/g. The stick force required to
achieve a load factor of 2,5 from steady level flight is:
69
225 N.
375 N.
450 N.
150 N.
For a normal stable aeroplane, the centre of gravity is located:70
aft of the neutral point of the aeroplane.
at the neutral point of the aeroplane.
with a sufficient minimum margin ahead of the neutral point of the aeroplane.
between the aft limit and the neutral point of the aeroplane.
The maximum aft position of the centre of gravity is, amongst others, limited by the:71
inability to achieve maximum rotation rate during take-off.
required minimum value of the stick force per g.
maximum longitudinal stability of the aeroplane.
maximum elevator deflection.
Longitudinal static stability is created by the fact that the:72
aeroplane possesses a large trim speed range.
wing surface is greater than the horizontal tail surface.
centre of gravity is located in front of the neutral point of the aeroplane.
centre of gravity is located in front of the leading edge of the wing.
Página 12 de 80Principles of Flight
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Positive static stability of an aeroplane means that following a disturbance from the
equilibrium condition:
73
the initial tendency is to return towards its equilibrium condition.
the initial tendency is to diverge further from its equilibrium condition.
the tendency is to move with an oscillatory motion of decreasing amplitude.
the tendency is to move with an oscillatory motion of increasing amplitude.
Following a disturbance, an aeroplane oscillates about the lateral axis at a constant
amplitude. The aeroplane is:
74
statically stable - dynamically neutral
statically unstable - dynamically stable
statically stable - dynamically unstable
statically unstable - dynamically neutral
Which statement on dynamic longitudinal stability of a conventional aeroplane is correct?75
Period time of the phugoid is normally 5 sec.
Speed remains constant during one period of the phugoid.
Damping of the phugoid is normally very weak.
Damping of the short period oscillation is normally very weak.
The "short period mode" is an:76
oscillation about the lateral axis.
oscillation about the vertical axis.
oscillation about the longitudinal axis.
unstable movement of the aeroplane, induced by the pilot.
An aeroplane that has positive static stability:77
is always dynamically stable.
is never dynamically stable.
can be dynamically stable, neutral or unstable.
is always dynamically unstable.
A statically unstable aeroplane is:78
never dynamically stable.
always dynamically stable.
sometimes dynamically stable.
sometimes dynamically unstable.
Página 13 de 80Principles of Flight
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One of the requirements for positive dynamic stability is:79
a large deflection range of the stabilizer trim.
a small cg range.
positive static stability.
an effective elevator.
"Tuck under" is:80
the tendency to nose down when speed is increased into the transonic flight regime.
the tendency to nose up when speed is increased into the transonic flight regime.
shaking of the control column at high Mach Number.
the tendency to nose down when the control column is pulled back.
"Tuck under" may happen at:81
low Mach numbers.
all Mach numbers.
high Mach numbers.
only at low altitudes.
"Tuck under" is caused by (i) which movement of the centre of pressure of the wing and (ii)
which change of the downwash angle at the location of the stabilizer.
82
(i) forward (ii) increasing
(i) aft (ii) decreasing
(i) forward (ii) decreasing
(i) aft (ii) increasing
Which of the following statements about dihedral is correct?83
Dihedral is necessary for the execution of slip-free turns.
Dihedral contributes to dynamic but not to static lateral stability.
The "effective dihedral" of an aeroplane component means the contribution of that component to the static lateral stability.
Effective dihedral is the angle between the 1/4-chord line and the lateral axis of the aeroplane.
How does positive camber of an aerofoil affect static longitudinal stability ? It has84
no effect, because camber of the aerofoil produces a constant pitch down moment coefficient, independent of angle of attack.
positive effect, because the centre of pressure shifts rearward at increasing angle of attack.
negative effect, because the lift vector rotates forward at increasing angle of attack.
positive effect, because the lift vector rotates backward at increasing angle of attack.
Página 14 de 80Principles of Flight
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Which of the following lists contain aeroplane design features that all increase static lateral
stability?
85
Low wing, dihedral, elliptical wing planform.
Fuselage mounted engines, dihedral, T-tail.
High wing, sweep back, large and high vertical fin.
Sweep back, under wing mounted engines, winglets.
Which wing design feature decreases the static lateral stability of an aeroplane?86
Increased wing span.
Anhedral.
Dihedral.
High wing.
The manoeuvrability of an aeroplane is best when the:87
flaps are down.
C.G. position is on the forward C.G. limit.
C.G. is on the aft C.G. limit.
speed is low.
The effect of a ventral fin on the static stability of an aeroplane is as follows:
(1=longitudinal, 2=lateral, 3=directional)
88
1: no effect, 2: negative, 3: positive
1: positive, 2: negative, 3: negative
1: negative, 2: positive, 3: positive
1: no effect, 2: positive, 3: negative
Which of the following statements about static lateral and directional stability is correct?89
An aeroplane with an excessive static directional stability in relation to its static lateral stability, will be prone to spiral dive (spiral instability).
The effects of static lateral and static directional stability are completely independent of each other because they take place about different axes.
An aeroplane with an excessive static directional stability in relation to its static lateral stability, will be prone to "Dutch roll".
Static directional stability can be increased by installing more powerful engines.
Which moments or motions interact in a dutch roll?90
Pitching and yawing.
Pitching and rolling.
Rolling and yawing.
Pitching and adverse yaw.
Página 15 de 80Principles of Flight
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(For this question use annex 081-1331A)
A jet transport aeroplane weighing 100 tons carries out a steady level 50 degree bank turn
at FL350. The buffet free speed range from low speed to high speed buffet extends from:
91
M 0.69 to > M 0.84
M 0.72 to > M 0.84
M 0.65 to > M 0.84
M 0.74 to M 0.84
Extension of FOWLER type trailing edge lift augmentation devices, will produce:92
no pitching moment.
a nose-up pitching moment.
a nose-down pitching moment.
a force which reduces drag.
Which of the following statements about a Mach trimmer is correct?93
A Mach trimmer corrects the change in stick force stability of a swept wing aeroplane above a certain Mach number.
A straight wing aeroplane always needs a Mach trimmer for flying at Mach numbers close to MMO.
A Mach trimmer reduces the stick force stability of a straight wing aeroplane to zero at high Mach numbers.
The Mach trimmer corrects the natural tendency of a swept wing aeroplane to pitch-up.
With increasing altitude and constant IAS the static lateral stability (1) and the dynamic
lateral/directional stability (2) of an aeroplane with swept-back wing will:
94
(1) increase (2) increase.
(1) decrease (2) decrease.
(1) increase (2) decrease.
(1) decrease (2) increase.
Which one of the following systems suppresses the tendency to "Dutch roll"?95
Yaw damper.
Roll spoilers.
Spoiler mixer.
Rudder limiter.
Which aeroplane behaviour will be corrected by a yaw damper ?96
Tuck under.
Spiral dive.
Dutch roll.
Buffeting.
Página 16 de 80Principles of Flight
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Compared with level flight prior to the stall, the lift (1) and drag (2) in the stall change as
follows:
97
(1) increases (2) decreases.
(1) decreases (2) increases.
(1) decreases (2) decreases.
(1) increases (2) increases.
Entering the stall the centre of pressure of a straight (1) wing and of a strongly swept back
wing (2) will:
98
(1) not move (2) move forward.
(1) move aft, (2) not move.
(1) move aft, (2) move forward.
(1) move aft, (2) move aft.
Which of the following statements about stall speed is correct ?99
Decreasing the angle of sweep of the wing will decrease the stall speed.
Increasing the angle of sweep of the wing will decrease the stall speed.
Use of a T-tail will decrease the stall speed..
Increasing the anhedral of the wing will decrease the stall speed.
Which of the following statements about the spin is correct?100
An aeroplane is prone to spin when the stall starts at the wing root.
In the spin, airspeed continuously increases.
During spin recovery the ailerons should be kept in the neutral position.
Every aeroplane should be designed such that it can never enter a spin.
During an erect spin recovery:101
the control stick is pulled to the most aft position.
the ailerons are held in the neutral position.
the control stick is moved side ways, against the angle of bank.
the control stick is moved side ways, in the direction of the angle of bank.
Which of the following statements about the stall of a straight wing aeroplane is correct?102
The horizontal tail will stall at a higher speed than the wing.
The nose down effect is the result of increasing downwash, due to flow separation.
Just before the stall the aeroplane will be have an increased nose-down tendency.
Buffeting is the result of tailplane flow separation..
Página 17 de 80Principles of Flight
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How is stall warning presented to the pilots of a large transport aeroplane ?103
stick shaker and/or aerodynamic buffet.
stick pusher.
stall warning light only.
aural warning only.
The vane of a stall warning system with a flapper switch is activated by the change of the:104
stagnation point.
centre of pressure.
centre of gravity.
point of lowest pressure.
Which combination of design features is known to be responsible for deep stall?105
Swept back wings and wing mounted engines.
Straight wings and a T-tail.
Swept back wings and a T-tail.
Straight wings and aft fuselage mounted engines
When a strongly swept back wing stalls and the wake of the wing contacts the horizontal
tail, the effect on the stall behaviour can be a(n):
106
nose up tendency and/or lack of elevator response.
nose down tendency.
increase in sensitivity of elevator inputs.
tendency to increase speed after initial stall.
The function of the stick pusher is:107
to activate and push the stick forward prior to stick shaker.
to vibrate the controls.
to activate and push the stick forward at or beyond a certain value of angle of attack.
to pull the stick, to avoid a high speed stall.
Dangerous stall characteristics, in large transport aeroplanes that require stick pushers to
be installed, include:
108
excessive wing drop and deep stall.
pitch down and yaw.
distinct aerodynamic buffet.
pitch down and increase in speed.
Página 18 de 80Principles of Flight
Questions
By what percentage does the lift increase in a level turn at 45° angle of bank, compared to
straight and level flight?
109
19%.
31%.
41%.
52%.
In a steady level, co-ordinated turn, the load factor n and the stalling speed VS will be:110
n greater than 1, VS higher than in straight and level flight.
n smaller than 1, VS lower than in straight and level flight.
n greater than 1, VS lower than in straight and level flight.
n smaller than 1, VS higher than in straight and level flight.
On a wing fitted with a "fowler" type trailing edge flap, the "Full extended" position will
produce:
111
an unaffected wing area and increase in camber.
an unaffected CD, at a given angle of attack.
an increase in wing area and camber.
an increase in wing area only.
When flaps are extended in a straight and level flight at constant IAS, the lift coefficient will
eventually:
112
first increase and then decrease.
remain the same.
increase.
decrease.
When flaps are deployed at constant angle of attack the lift coefficient will:113
vary as the square of IAS.
remain the same.
increase.
decrease.
Trailing edge flap extension will:114
decrease the critical angle of attack and increase the value of CLmax.
increase the critical angle of attack and increase the value of CLmax.
decrease the critical angle of attack and decrease the value of CLmax.
increase the critical angle of attack and decrease the value of CLmax.
Página 19 de 80Principles of Flight
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Which of the following statements about the difference between Krueger flaps and slats is
correct?
115
Deploying a Krueger flap will form a slot, deploying a slat does not.
Deploying a slat will increase critical angle of attack, deploying a Krueger flap does not.
Deploying a slat will form a slot, deploying a Krueger flap does not.
Deploying a Krueger flap will increase critical angle of attack, deploying a slat does not.
What is the most effective flap system?116
Single slotted flap.
Fowler flap.
Split flap.
Plain flap.
Deploying a Fowler flap, the flap will:117
just turn down.
just move aft.
move aft, then turn down.
turn down, then move aft.
A slotted flap will increase the CLmax by:118
increasing the camber of the aerofoil and re-energising the airflow.
decreasing the skin friction.
increasing only the camber of the aerofoil.
increasing the critical angle of attack.
In order to maintain straight and level flight at a constant airspeed, whilst the flaps are
being retracted, the angle of attack must be:
119
increased or decreased depending upon the type of flap
increased
decreased
held constant
What is the purpose of an auto-slat system ?120
ensures that the slats are always extended when the ground/flight system is in the "ground" position.
assist the ailerons during rolling.
extend automatically when a certain value of angle of attack is exceeded.
provide automatically slat IN selection after take-off.
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The function of the slot between an extended slat and the leading edge of the wing is to:121
cause a venturi effect which energizes the boundary layer.
allow space for vibration of the slat.
reduce the wing loading.
slow the air flow in the slot so that more pressure is created under the wing.
Given the following aeroplane configurations:
1. Clean wing
2. Slats only extended
3. Flaps only extended
Place these configurations in order of stall angle of attack:
122
1, 3, 2.
2, 1, 3.
3, 1, 2.
2, 3, 1.
An aeroplane has the following flap settings: 0°, 15°, 30° and 45°. Slats can also be
selected. Which of the following selections will most adversely affect the CL/CD ratio?
123
Flaps from 30° to 45°.
The slats.
Flaps from 0° to 15°.
Flaps from 15° to 30°.
After take-off the slats (when installed) are always retracted later than the flaps. Why ?124
Because SLATS EXTENDED provides a better view from the cockpit than FLAPS EXTENDED.
Because VMCA with SLATS EXTENDED is more favourable compared to the FLAPS EXTENDED situation.
Because SLATS EXTENDED gives a large decrease in stall speed with relatively less drag.
Because FLAPS EXTENDED gives a large decrease in stall speed with relatively less drag.
Upon extension of a spoiler on a wing:125
CD is increased and CL is decreased.
only CL is decreased (CD remains unaffected).
both CL and CD are increased.
CD is increased, while CL remains unaffected.
When "spoilers" are used as speed brakes:126
CLmax of the polar curve is not affected.
they do not affect wheel braking action during landing.
at same angle of attack, CD is increased and CL is decreased.
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at same angle of attack, CL remains unaffected.
During initiation of a turn with speedbrakes extended, the roll spoiler function induces a
spoiler deflection:
127
on the downgoing wing only.
downward on the upgoing wing and upward on the downgoing wing.
upward on the upgoing wing and downward on the downgoing wing.
on the upgoing wing only.
Stick forces, provided by an elevator feel system, depend on:128
elevator deflection, static pressure.
stabilizer position, total pressure.
elevator deflection, dynamic pressure.
stabilizer position, static pressure.
For a fixed-pitch propeller designed for cruise, the angle of attack of each blade, measured
at the reference section:
129
is optimum when the aircraft is in a stabilized cruising flight.
decreases when the aircraft speed decreases (with identical engine RPM).
is lower in ground run than in flight (with identical engine RPM).
is always positive during idling descent.
Why is a propeller blade twisted from root to tip?130
To ensure the angle of attack is greatest at the tip.
To ensure that the root produces most thrust.
To maintain a constant angle of attack along the whole length of the propeller blade.
To ensure that the tip produces most thrust.
Constant-speed propellers provide a better performance than fixed-pitch propellers because
they:
131
have more blade surface area than a fixed-pitch propeller.
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.
If you pull back the RPM lever of a constant speed propeller during a glide with idle power
and constant speed, the propeller pitch will:
132
decrease and the rate of descent will increase.
decrease and the rate of descent will decrease.
increase and the rate of descent will decrease.
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increase and the rate of descent will increase.
If you push forward the RPM lever of a constant speed propeller during a glide with idle
power and constant speed, the propeller pitch will:
133
decrease and the rate of descent will increase.
increase and the rate of descent will decrease.
increase and the rate of descent will increase.
decrease and the rate of descent will decrease.
Propeller efficiency may be defined as the ratio between:134
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.
An engine failure can result in a windmilling (1) propeller and a feathered (2) propeller.
Which statement about propeller drag is correct?
135
(2) is larger than (1).
(1) is equal to (2).
(1) is larger than (2).
impossible to say which one is largest.
When the blades of a propeller are in the feathered position:136
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.
Increasing the number of propeller blades will:137
increase the propeller efficiency.
increase the noise level at maximum power.
increase the maximum absorption of power.
decrease the torque in the propeller shaft at maximum power.
The torque effect during the take off run in respect of a right hand propeller, when viewed
from behind, will tend to:
138
roll the aeroplane to the left.
pitch the aeroplane nose down.
roll the aeroplane to the right.
pitch the aeroplane nose up.
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Questions
Gyroscopic precession of a propeller is induced by:139
pitching and rolling.
increasing RPM and yawing.
pitching and yawing.
increasing RPM and rolling.
Asymmetric propeller blade effect is mainly induced by:140
the inclination of the propeller axis to the relative airflow.
high speed.
large angles of yaw.
large angles of climb.
A propeller is turning to the right when viewed from behind. The asymmetric blade effect in
the climb at low speed will:
141
roll the aeroplane to the left.
yaw the aeroplane to the right.
yaw the aeroplane to the left.
roll the aeroplane to the right.
A jet transport aeroplane is in a straight climb at a constant IAS and constant weight. The
operational limit that may be exceeded is:
142
MD.
MMO.
VMO.
VA.
How does stalling speed (IAS) vary with altitude?143
It remains constant at lower altitudes but decreases at higher altitudes due to compressibility effects.
It increases with increasing altitude, because the density decreases.
It remains constant at lower altitudes but increases at higher altitudes due to compressibility effects.
It remains constant.
What data may be obtained from the Buffet Onset Boundary chart?144
The values of the Mach Number at which low speed and Mach Buffet occur at different weights and altitudes.
The values of MMO at different weights and altitudes.
The values of Mcrit at different weights and altitudes.
The values of the Mach Number at which low speed and shock-stall occur at different weights and altitudes.
Página 24 de 80Principles of Flight
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Mcrit is the free stream Mach Number at which:145
Mach buffet occurs.
shockstall occurs.
somewhere about the airframe Mach 1 is reached locally.
the critical angle of attack is reached.
Which of the following (1) aerofoils and (2) angles of attack will produce the lowest Mcrit
values?
146
(1) thin and (2) small.
(1) thick and (2) large.
(1) thick and (2) small.
(1) thin and (2) large.
Which kind of flow separation occurs at the smallest angle of attack?147
deep stall.
low-speed stall.
shockstall.
Accelerated stall.
When the Mach number is slowly increased in straight and level flight the first shockwaves
will occur:
148
on the upper surface at the wing root.
on the lower surface of the wing.
somewhere on the fin.
somewhere on the horizontal tail.
The consequences of exceeding Mcrit in a swept-wing aeroplane may be: (assume no
corrective devices, straight and level flight)
149
buffeting of the aeroplane and a tendency to pitch up.
buffeting of the aeroplane and a tendency to pitch down.
an increase in speed and a tendency to pitch up.
engine unbalance and buffeting.
A jet aeroplane cruises buffet free at high constant altitude. Which type of stall can occur if
this aeroplane decelerates during an inadvertent increase in load factor ?
150
Shock stall.
Deep stall.
Accelerated stall.
Low speed stall.
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Which type of stall has the largest associated angle of attack?151
Deep stall.
Shock stall.
Accelerated stall.
Low speed stall.
The maximum acceptable cruising altitude is limited by a minimum acceptable loadfactor
because exceeding that altitude:
152
turbulence may exceed the limit load factor.
a sudden necessary bankangle may exceed the limit load factor.
turbulence may induce Mach buffet.
Mach buffet will occur immediately.
If an aeroplane is accelerated from subsonic to supersonic speeds, the centre of pressure
will move:
153
to the mid chord position.
forward.
to a position near the leading edge.
to a position near the trailing edge.
Vortex generators on the upper side of the wing surface will:154
increase the critical Mach Number.
decrease the span wise flow at high Mach Numbers.
decrease the intensity of shock wave induced air separation.
increase the magnitude of the shock wave.
Vortex generators on the upper side of the wing:155
decrease wave drag.
increase wave drag.
increase critical Mach Number.
decrease critical Mach Number.
The aft movement of the centre of pressure during acceleration through the transonic range
will:
156
decrease the longitudinal stability.
increase the static lateral stability.
increase the static longitudinal stability.
decrease the static lateral stability.
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In supersonic flight aerofoil pressure distribution is:157
the same as in subsonic flight.
rectangular.
irregular.
triangular.
Shock stall is:158
separation of the flow at the trailing edge of the wing at high Mach Numbers.
separation of the flow at high angles of attack and at high Mach Numbers.
separation of the boundary layer behind the shock wave.
separation of the flow behind the bow wave.
In the transonic range the aeroplane characteristics are strongly determined by:159
the Mach Number.
the TAS.
the IAS.
the CAS.
Which of the following flight phenomena can only occur at Mach numbers above the critical
Mach number?
160
Dutch roll.
Speed instability.
Mach buffet.
Elevator stall.
Which of the following flight phenomena can occur at Mach numbers below the critical
Mach number?
161
Shock stall.
Dutch roll.
Tuck under.
Mach buffet.
The Mach trim system will:162
adjust the elevator trim tab, depending on the Mach Number.
pump the fuel from tank to tank, depending on the Mach Number.
adjust the stabilizer, depending on the Mach Number.
keep the Mach Number automatically constant.
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The Mach trim system will prevent:163
tuck under.
dutch roll.
buffeting.
shock stall.
When air has passed an expansion wave, the static pressure is:164
unchanged.
decreased.
decreased or increased, depending on Mach Number.
increased.
The critical Mach Number of an aeroplane is the free stream Mach Number, which
produces the first evidence of:
165
supersonic flow.
shock wave.
buffet.
local sonic flow.
The critical Mach Number of an aeroplane can be increased by:166
sweep back of the wings.
vortex generators.
control deflection
dihedral of the wings.
In supersonic flight, all disturbances produced by an aeroplane are:167
outside the conical area depending on the Mach Number.
in front of the aeroplane.
in between a conical area, depending on the Mach Number.
very weak and negligible.
In transonic flight the ailerons will be less effective than in subsonic flight because:168
aileron deflection only affects the air in front of the shock wave.
aileron deflection only partly affects the pressure distribution around the wing.
behind the shock wave pressure is lower.
aileron down deflection moves the shock wave forward.
To be able to predict compressibility effects you have to determine the:169
Página 28 de 80Principles of Flight
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IAS.
TAS.
Mach Number.
EAS.
The formula for the Mach Number is:
(a= speed of sound)
170
M= TAS / a
M= a / TAS
M= TAS*a
M= IAS / a
Assuming ISA conditions, climbing at a constant Mach Number up to FL 350 the TAS will:171
decrease.
first increase, then decrease.
increase.
remain constant.
The speed of sound is affected by the:172
density of the air.
pressure of the air.
temperature of the air.
humidity of the air.
An aeroplane is flying through the transonic range. As the Mach Number increases the
centre of pressure of the wing will move aft. This movement requires:
173
a pitch up input of the stabilizer.
a stability augmentation system to improve dynamic stability.
much more thrust from the engine.
a higher IAS to compensate the nose down effect.
The additional increase of drag at Mach Numbers above the critical Mach Number is due to:174
increased angle of attack.
increased interference drag.
wave drag.
increased skin friction.
Air passes a normal shock wave. Which of the following statements is correct?175
The velocity increases.
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Questions
The static temperature increases.
The static pressure decreases.
The static temperature decreases.
The bow wave will first appear at:176
the critical Mach number
Mach 1
a Mach number just above M = 1
a Mach number just below M = 1
Two methods to increase the critical Mach Number are:177
thin aerofoils and sweep back of the wing.
thin aerofoils and dihedral of the wing.
positive cambering of the aerofoil and sweep back of the wing.
thick aerofoils and dihedral of the wing.
A commercial jet aeroplane is performing a straight descent at a constant Mach number
with constant mass. The operational speed limit that may be exceeded is:
178
VMO.
VNE.
VD.
MMO.
The relationship between the stall speed VS and VA (EAS) for a large transport aeroplane
can be expressed in the following formula:
(SQRT= square root)
179
VA < VS SQRT(2.5)
VA <= VS SQRT(2.5)
VA > VS SQRT(2.5)
VA >= VS SQRT(2.5)
By what percentage does VA (EAS) alter when the aeroplane's weight decreases by 19%?180
4.36% lower.
no change
19% lower.
10% lower.
Which load factor determines VA?181
manoeuvring ultimate load factor.
gust load factor at 66 ft/sec gust.
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Questions
manoeuvring limit load factor.
manoeuvring flap limit load factor.
Which combination of speeds is applicable for structural strength in gust (clean
configuration) ?
182
50 ft/sec and VC.
66 ft/sec and VD.
65 ft/sec at all speeds.
55 ft/sec and VB.
The extreme right limitation for both V-n (gust and manoeuvre) diagrams is created by the
speed:
183
VC
Vflutter
VD
VMO
What can happen to the aeroplane structure flying at a speed just exceeding VA ?184
It may suffer permanent deformation if the elevator is fully deflected upwards
It may break if the elevator is fully deflected upwards.
It may suffer permanent deformation because the flight is performed at too large dynamic pressure.
It will collapse if a turn is made.
What is the limit load factor of a large transport aeroplane in the manoeuvring diagram?185
1.5
3.75
2.5
6
The most important problem of ice accretion on a transport aeroplane during flight is:186
blocking of control surfaces.
reduction in CLmax.
increase in weight.
increase in drag.
The effects of very heavy rain (tropical rain) on the aerodynamic characteristics of an
aeroplane are:
187
increase of CLmax and increase of drag.
increase of CLmax and decrease of drag.
decrease of CLmax and increase of drag.
Página 31 de 80Principles of Flight
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decrease of CLmax and decrease of drag.
While flying under icing conditions, the largest ice build-up will occur, principally, on:188
The frontal areas of the aircraft.
The upper and lower surfaces on the rear of the wing.
The upper and lower rudder surfaces.
The pitot and static probes only.
The frontal area of a body, placed in a certain airstream is increased by a factor 3. The
shape will not alter. The aerodynamic drag will increase with a factor:
189
9 .
6 .
3 .
1.5 .
The aerodynamic drag of a body, placed in a certain airstream depends amongst others on:190
The c.g. location of the body.
The airstream velocity.
The specific mass of the body.
The weight of the body.
A body is placed in a certain airstream. The airstream velocity increases by a factor 4. The
aerodynamic drag will increase with a factor:
191
12 .
8 .
16 .
4 .
A body is placed in a certain airstream. The density of the airstream decreases to half of the
original value. The aerodynamic drag will decrease with a factor:
192
2 .
4 .
8 .
1.4 .
The point, where the aerodynamic lift acts on a wing is:193
the centre of pressure.
the c.g. location.
the point of maximum thickness of the wing.
the suction point of the wing.
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The location of the centre of pressure of a positive cambered wing at increasing angle of
attack will:
194
shift aft.
not shift.
shift forward.
shift in spanwise direction.
The unit of density is:195
kg/m³
psi
kg/cm²
Bar
The unit of measurement of pressure is:196
kg/m³
lb/gal
psi
kg/dm²
The boundary layer of a wing is:197
a layer on the wing in which the stream velocity is lower than the free stream velocity.
created by the normal shock wave at transonic speeds.
a turbulent flow around the wing.
caused by suction on the upper wing surface.
A laminar boundary layer is a layer, in which:198
the vortices are weak.
the velocity is constant.
no velocity components exist, normal to the surface.
the temperature varies constantly.
Total pressure is:199
static pressure plus dynamic pressure.
static pressure minus dynamic pressure.
½ rho V²
measured at a small hole in a surface, parallel to the local stream.
The (subsonic) static pressure:200
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Questions
is the total pressure plus the dynamic pressure.
is the pressure in a point at which the velocity has become zero.
decreases in a flow in a tube when the diameter decreases.
increases in a flow in a tube when the diameter decreases.
The true airspeed (TAS) is:201
lower than the speed of the undisturbed airstream about the aeroplane.
lower than the indicated airspeed (IAS) at ISA conditions and altitudes below sea level.
higher than the speed of the undisturbed airstream about the aeroplane.
equal to the IAS, multiplied by the air density at sea level.
The lift- and drag forces, acting on a wing cross section:202
vary linearly with the angle of attack.
are proportional to each other, independent of angle of attack.
depend on the pressure distribution about the wing cross section.
are normal to each other at just one angle of attack.
The lift force, acting on an aerofoil:203
is mainly caused by suction on the upperside of the aerofoil.
increases, proportional to the angle of attack until 40 degrees.
is mainly caused by overpressure at the underside of the aerofoil.
is maximum at an angle of attack of 2 degrees.
The relative thickness of an aerofoil is expressed in:204
camber.
meters.
% chord.
degrees cross section tail angle.
The aerofoil polar is:205
a graph, in which the thickness of the wing aerofoil is given as a function of the chord.
a graph of the relation between the lift coefficient and the drag coefficient.
a graph of the relation between the lift coefficient and the angle of attack.
the relation between the horizontal and the vertical speed.
The aspect ratio of the wing:206
is the ratio between chord and root chord.
is the ratio between the tip chord and the wing span.
is the ratio between the wing span and the mean geometric chord.
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is the ratio between the wing span and the root chord.
Dihedral of the wing is:207
the angle between the 0.25 chord line of the wing and the lateral axis.
the angle between the leading edge of the wing and the lateral axis.
the angle between the 0.25 chord line of the wing and the vertical axis.
the angle between the 0.25 chord line of the wing and the horizon.
The induced drag:208
increases as the lift coefficient increases.
increases as the aspect ratio increases.
has no relation to the lift coefficient.
increases as the magnitude of the tip vortices decreases.
Flap selection at constant IAS whilst maintaining straight and level flight will increase the:209
maximum lift coefficient (CLmax) and the drag.
lift and the drag.
lift coefficient and the drag.
stall speed.
The Mach number:210
is the ratio between the TAS of the aeroplane and the local speed of sound.
is the ratio between the TAS of the aeroplane and the speed of sound at sea level.
is the ratio between the IAS of the aeroplane and the local speed of sound.
increases at a given TAS, when the temperature rises.
A normal shock wave:211
is a discontinuity plane in an airflow, in which the temperature drops suddenly.
is a discontinuity plane in an airflow, in which the pressure drops suddenly.
can occur at different points on the aeroplane in transonic flight.
is a discontinuity plane in an airflow, which is always normal to the surface.
If the sum of all the moments in flight is not zero, the aeroplane will rotate about the:212
centre of gravity.
neutral point of the aeroplane.
aerodynamic centre of the wing.
centre of pressure of the wing.
Dihedral of the wing:213
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Questions
is the only way to increase the static lateral stability.
is only positive for aeroplanes with high mounted wings.
increases the static lateral stability.
decreases the static lateral stability.
A C.G location beyond the aft limit leads to:214
an unacceptable low value of the manoeuvre stability (stick force per g, Fe/g).
a too high pulling stick force during rotation in the take off.
an increasing static longitudinal stability.
a better recovery performance in the spin.
If the elevator trim tab is deflected up, the cockpit trim indicator presents:215
neutral.
nose-up.
nose-down.
nose-left.
Differential aileron deflection:216
is required to achieve the required roll-rate.
equals the drag of the right and left aileron.
is required to keep the total lift constant when ailerons are deflected.
increases the CLmax.
An example of differential aileron deflection during initiation of left turn is:217
Left aileron: 2° downRight aileron: 5° up
Left aileron: 5° downRight aileron: 2° up
Left aileron: 5° upRight aileron: 2° down
Left aileron: 2° upRight aileron: 5° down
Does the pitch-angle of a constant-speed propeller alter in medium horizontal turbulence?218
Yes slightly.
Yes strongly.
No.
Yes, but only if the pitch is full-fine.
When trailing edge flaps are selected down whilst maintaining straight and level flight at
constant IAS:
219
Página 36 de 80Principles of Flight
Questions
the lift coefficient and the drag coefficient increase.
the stall speed increases.
the centre of pressure moves aft.
the total boundary layer becomes laminar.
Which of the following situations leads to a decreasing stall speed (IAS)?220
increasing load factor.
decreasing weight.
increasing altitude.
increasing air density.
Two identical aircraft A and B, with the same mass, are flying steady level co-ordinated 20
degree bank turns. If the TAS of A is 130 kt and that of B is 200 kt:
221
the lift coefficient of A is less than that of B.
the turn radius of A is greater than that of B.
the rate of turn of A is greater than that of B.
the load factor of A is greater than that of B.
Which of the following statements about a constant speed propeller is correct?222
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.
The difference between IAS and TAS will:223
decrease with decreasing altitude.
increase with decreasing temperature.
increase with increasing air density.
decrease with increasing speed.
Increase of wing loading will:224
increase the stall speeds.
decrease take off speeds.
increase CLmax.
decrease the minimum gliding angle.
An aeroplane performs a right turn, the slip indicator is left of neutral. One way to co-
ordinate the turn is to apply:
225
more left rudder.
Página 37 de 80Principles of Flight
Questions
more right rudder.
less right bank.
a higher turn-rate.
A light twin is in a turn at 20 degrees bank and 150 kt TAS. A more heavy aeroplane at the
same bank and the same speed will:
226
turn at a bigger turn radius.
turn at a smaller turn radius.
turn at the same turn radius.
turn at a higher turn rate.
Which statement is correct about an aeroplane, that has experienced a left engine failure
and continues afterwards in straight and level cruise flight with wings level ?
227
turn indicator left of neutral, slip indicator neutral.
turn indicator neutral, slip indicator neutral.
turn indicator neutral, slip indicator left of neutral.
turn indicator left of neutral, slip indicator left of neutral.
The bank angle in a rate-one turn depends on:228
wind.
load factor.
TAS.
weight.
Which statement about induced drag and tip vortices is correct?229
The flow direction at the upper side of the wing has a component in wing root direction, the flow at the underside of the wing in wing tip direction.
Tip vortices can be diminished by vortex generators.
The flow direction at the upper and under side of the wing, both deviate in wing tip direction.
The wing tip vortices and the induced drag decrease at increasing angle of attack.
VA is:230
the maximum speed at which maximum elevator deflection up is allowed.
the maximum speed at which rolls are allowed.
the speed at which a heavy transport aeroplane should fly in turbulence.
the speed that should not be exceeded in the climb.
The critical Mach number for an aerofoil equals the free stream airfoil Mach number at
which:
231
a shock-wave appears on the upper surface.
Página 38 de 80Principles of Flight
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a "supersonic bell" appears on the upper surface.
sonic speed (M=1) is reached at a certain point on the upper side of the aerofoil.
the maximum operating temperature is reached.
Compared with stalling airspeed (VS) in a given configuration, the airspeed at which stick
shaker will be triggered is:
232
1.20 VS.
1.30 VS.
1.12 VS.
greater than VS.
VMO:233
should be chosen in between VC and VD.
is equal to the design speed for maximum gust intensity.
should be not greater than VC.
should not be less than VD.
The term angle of attack in a two dimensional flow is defined as:234
the angle between the wing chord line and the direction of the relative wind/airflow.
the angle between the aeroplane climb path and the horizon.
the angle formed by the longitudinal axis of the aeroplane and the chord line of the wing
the angle for maximum lift/drag ratio
The terms "q" and "S" in the lift formula are:235
dynamic pressure and the area of the wing
static pressure and dynamic pressure
square root of surface and wing loading
static pressure and wing surface area
The critical angle of attack:236
remains unchanged regardless of gross weight
increases if the CG is moved forward
decreases if the CG is moved aft
changes with an increase in gross weight
Comparing the lift coefficient and drag coefficient at normal angle of attack:237
CL is much greater than CD
CL has approximately the same value as CD
CL is lower than CD
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CL is much lower than CD
Which statement is correct in respect of Cl and angle of attack?238
For an asymmetrical aerofoil, if the angle of attack is zero, Cl is zero.
For a symmetrical aerofoil, if the angle of attack is zero, Cl is zero.
For a symmetrical aerofoil, if the angle of attack is zero, Cl is not zero.
For an asymmetrical aerofoil with positive camber, if the angle of attack is greater than zero, Cl is zero.
The polar curve of an aerofoil is a graphic relation between:239
TAS and stall speed
Angle of attack and CL
CD and angle of attack
CL and CD
The Mean Aerodynamic Chord (MAC) for a given wing of any planform is240
the chord of a rectangular wing with same moment and lift
the chord of a large rectangular wing
the average chord of the actual aeroplane
the wing area divided by the wing span
The span-wise flow is caused by the difference between the air pressure on top and beneath
the wing and its direction of movement goes from:
241
beneath to the top of the wing via the wing tip
the top to beneath the wing via the wing's trailing edge
beneath to the top of the wing via the trailing edge
the top to beneath the wing via the leading edge
Induced drag may be reduced by:242
a decrease of the aspect ratio
the use of a wing tip with a much thinner aerofoil
an increase in the taper ratio of the wing
an increase in aspect ratio
The relationship between induced drag and the aspect ratio is:243
there is no relationship
induced drag = 1.3 aspect ratio value
an increase in the aspect ratio increases the induced drag
a decrease in the aspect ratio increases the induced drag
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A high aspect ratio wing produces:244
less sensitivity to gust effects
a decrease in stall speed
a decrease in induced drag
an increase in induced drag
What is the effect on induced drag of mass and speed changes? (all other factors of
importance remaining constant)
245
Decreases with increasing speed and decreasing mass.
Decreases with decreasing speed and decreasing mass.
Increases with increasing speed and decreasing mass.
Increases with increasing speed and increasing mass.
What will happen in ground effect?246
The induced angle of attack and induced drag decrease.
The thrust required will increase significantly.
The wing downwash on the tail surfaces increases.
The wing tip vortices increase in strength.
Floating due to ground effect during an approach to land will occur:247
when the height is less than halve of the length of the wing span above the surface
when the height is less than twice the length of the wing span above the surface
when a higher than normal angle of attack is used
at a speed approaching the stall
Which statement is correct about the laminar and turbulent boundary layer:248
friction drag will be equal in both types of layers
friction drag is lower in the turbulent layer
friction drag is lower in the laminar layer
separation point will occur earlier in the turbulent layer
After the transition point between the laminar and turbulent boundary layer249
the boundary layer gets thicker and the speed decreases
the mean speed and friction drag increases
the boundary layer gets thinner and the speed increases
the mean speed increases and the friction drag decreases
The stall speed:250
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increases with the length of the wingspan
does not depend on weight
increases with an increased weight
decreases with an increased weight
At higher altitudes, the stall speed (IAS):251
increases
decreases
remains the same
decreases until the tropopause
When a pilot makes a turn in horizontal flight, the stall speed:252
increases with the square root of load factor
increases with flap extension
decreases with increasing bank angle
increases with the load factor squared
The stall speed in a 60° banked turn increases by the following factor:253
2.00
1.30
1.07
1.41
The trailing edge flaps when extended:254
increase the zero lift angle of attack
significantly increase the angle of attack for maximum lift
significantly lower the drag
degrade the best angle of glide
When trailing edge flaps are extended in level flight, the change in pitching moment,
ignoring any effects on the tailplane, will be:
255
nose up.
zero.
nose down.
dependent on cg location.
Deflection of leading edge flaps will:256
increase critical angle of attack.
decrease CLmax.
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decrease drag.
not affect critical angle of attack.
Slat extension will:257
reduce tip vortices.
create gaps between leading edge and engine nacelles.
increase the critical angle of attack.
decrease the energy in the boundary layer on the upperside of the wing.
Spoiler deflection causes:258
an increase in drag and decrease in lift
an increase in lift and drag
an increase in lift only
decrease in lift and drag
An aeroplane performs a continuous descent with 160 kts IAS and 1000 feet/min vertical
speed. In this condition:
259
lift is equal to weight
lift is less than drag
weight is greater than lift
drag is less than the combined forces that move the aeroplane forward
An aeroplane is descending at a constant Mach number from FL 350. What is the effect on
true airspeed ?
260
It remains constant
It increases as temperature increases
It decreases as pressure increases
It decreases as altitude decreases
A jet aeroplane is cruising at high altitude with a Mach-number, that provides a buffet
margin of 0.3g incremental. In order to increase the buffet margin to 0.4g incremental the
pilot must:
261
fly at a larger angle of attack
fly at a higher Mach-number
fly at a lower altitude and the same Mach-number
extend the flaps to the first selection
One disadvantage of wing sweep is the stalling characteristics. At the stall:262
tip stall will occur first, which produces a pitch-up moment.
wing root stall will occur first, which produces a rolling moment
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tip stall will occur first, which produces a nose-down moment
leading edge stall will occur first, which produces a nose-down moment
For an aeroplane with one fixed value of VA the following applies. VA is:263
the maximum speed in smooth air
the speed at which unrestricted application of elevator control can be used, without exceeding the maximum manoeuvring limit load factor
the speed at which the aeroplane stalls at the manoeuvring limit load factor at MTOW.
just another symbol for the rough air speed
What factors determine the distance travelled over the ground of an aeroplane in a glide ?264
The wind and weight together with power loading, which is the ratio of power output to the weight
The wind and the lift/drag ratio, which changes with angle of attack
The wind and the aeroplane's mass
The wind and CLmax
The following unit of measurement: kgm/s² is expressed in the SI-system as:265
Watt
Joule
Newton
Pascal
Excluding constants, the coefficient of induced drag (CDi) is the ratio of:266
CL² and AR (aspect ratio)
CL and CD
CL and b (wing span)
CL²and S (wing surface)
Critical Mach number is the free stream Mach number at which:267
local supersonic flow first exists on any part of the aeroplane.
there is subsonic flow over all parts of the aeroplane.
there is supersonic flow over all parts of the aeroplane.
the aeroplane has zero buffet margin.
One important advantage the turbulent boundary layer has over the laminar layer is that:268
skin friction drag is less
energy is less
it is thinner
it has less tendency to separate from the surface
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The Mach-trim function is installed on most commercial jets in order to minimize the
adverse effects of:
269
increased drag due to shock wave formation
uncontrolled changes in stabilizer setting
compressibility effects on the stabilizer
changes in the position of centre of pressure
When comparing a rectangular wing and a swept back wing of the same wing area and wing
loading, the swept back wing has the advantage of:
270
Greater strength
Increased longitudinal stability
Higher critical Mach number
Lower stalling speed
Which kind of ''tab'' is commonly used in case of manual reversion of fully powered flight
controls ?
271
Servo tab
Spring tab
Balance tab
Anti-balance tab
Which statement is correct about a normal shock wave ?272
The airflow changes direction
The airflow changes from subsonic to supersonic
The airflow changes from supersonic to subsonic
The airflow expands when passing the aerofoil
High Aspect Ratio, as compared with low Aspect Ratio, has the effect of:273
Decreasing induced drag and critical angle of attack
Increasing lift and critical angle of attack
Increasing lift and drag
Increasing induced drag and decreasing critical angle of attack
What wing shape or wing characteristic is the least sensitive to turbulence:274
straight wings
wing dihedral
swept wings
elliptical wing
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"A line connecting the leading- and trailing edge midway between the upper and lower
surface of a aerofoil". This definition is applicable for:
275
the upper camber line
the camber line
the chord line
the mean aerodynamic chord line
One advantage of a movable-stabilizer system compared with an elevator trim system is that:276
it leads to greater stability in flight
the system's complexity is reduced
it is a more effective means of trimming
the complete system (structure and control mechanism) weighs less
An aeroplane has a stall speed of 78 KCAS at its gross weight of 6850 Ibs. What is the stall
speed when the weight is 5000 Ibs ?
277
67 KCAS
91 KCAS
78 KCAS
57 KCAS
Which statement is correct about a spring tab ?278
At low IAS it behaves like a servo tab
At high IAS it behaves like a fixed extension of the elevator
At high IAS it behaves like a servo tab
Its main purpose is to increase stick force per g
How is adverse yaw compensated for during entry into and roll out from a turn ?279
Servo tabs
Differential aileron deflection
Horn-balanced controls
Anti-balanced rudder control
What increases the stalling angle of attack ? Use of:280
fuselage mounted speed-brakes
spoilers
slats
flaps
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What is the unit of measurement for power ?281
Nm/s
kgm/s²
Pa/m²
N/m
The use of a slot in the leading edge of the wing enables the aeroplane to fly at a slower
speed because:
282
it delays the stall to a higher angle of attack
the laminar part of the boundary layer gets thicker
it decelerates the upper surface boundary layer air
it changes the camber of the wing
The angle of attack of a fixed pitch propeller blade increases when:283
forward velocity increases and RPM decreasing
velocity and RPM increase
RPM increases and forward velocity decreases
velocity and RPM decrease
What is the approximate value of the lift of an aeroplane at a gross weight of 50 000 N, in a
horizontal coordinated 45 degrees banked turn ?
284
70 000 N
60 000 N
50 000 N
80 000 N
Load factor is:285
Weight/Lift
1/Bank angle
Lift/Weight
Wing loading
Which has the effect of increasing load factor ? (all other relevant factors being constant)286
Vertical gusts
Increased aeroplane mass
Increased air density
Rearward CG location
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In twin-engine aeroplanes with right turning propellers287
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 left engine is the critical motor.
the right engine is the critical motor.
The continuity equation states: If the area of a tube is increasing, the speed of the subsonic
and incompressible flow inside is
288
decreasing.
not changing.
increasing.
sonic.
If the continuity equation is applicable, what will happen to the air density (rho) if the cross
sectional area of a tube changes ? (low speed, subsonic and incompressible flow)
289
rho1 < rho2
rho1 > rho2
rho1 = rho2
The density depends on the change of the tube area.
Which statement is correct regarding a shockwave on a lift generating wing?435
It moves slightly aft when an aileron is deflected downward.
It reaches its highest strength when flying at the critical Mach number.
It moves forward when the Mach number is increased.
It is located at the greatest wing thickness when the aeroplane reaches the speed of sound.
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Which statement is correct about the gust load on an aeroplane, while all other factors of
importance remain constant?
I When the mass increases, the gust load increases.
II When the altitude decreases, the gust load increases.
436
I is incorrect, II is incorrect.
I is correct, II is correct.
I is incorrect, II is correct.
I is correct, II is incorrect.
An aeroplane is in a steady horizontal turn at a TAS of 194.4 kt. The turn radius is 1000 m.
The bank angle is: (assume g = 10 m/sec2)
437
45°
30°
50°
60°
An aeroplane should be equipped with a Mach trimmer, if:438
stick force stability is independent of the airspeed and -altitude.
stick force per g strongly decreases at low Mach numbers.
at transonic Mach numbers the aeroplane demonstrates unconventional elevator stick force characteristics.
at high airspeed and low altitude the aeroplane demonstrates unconventional elevator stick force characteristics.
The manoeuvre stability of a large jet transport aeroplane is 280 N/g. What stick force is
required, if the aeroplane is pulled to the limit manoeuvring load factor from a trimmed
horizontal straight and steady flight? (cruise configuration)
439
1050 N
420 N
770 N
630 N
Upward deflection of a trim tab in the longitudinal control results in:440
the stick force stability remaining constant.
increasing the stick force stability.
the stick position stability remaining constant.
increasing the stick position stability.
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Which statement is correct?
I Stick force per g is independent of altitude.
II Stick force per g increases when the centre of gravity moves forward.
441
I is incorrect, II is correct.
I is correct, II is correct.
I is correct, II is incorrect.
I is incorrect, II is incorrect
The following factors increase stall speed:442
a higher weight, selecting a higher flap setting, a forward c .g. shift.
increasing bank angle, increasing thrust, slat extension.
an increase in load factor, a forward c.g. shift, decrease in thrust.
a lower weight, decreasing bank angle, a smaller flapsetting.
Which statement is correct?443
The stagnation point is always situated on the chordline, the centre of pressure is not.
As the angle of attack increases, the stagnation point on the wing's profile moves downwards.
The centre of pressure is the point on the wing's leading edge where the airflow splits up.
The stagnation point is another name for centre of pressure.
How will the density and static temperature change in a supersonic flow from a position in
front of a shock wave to behind it ?
444
Density will decrease, static temperature will decrease.
Density will decrease, static temperature will increase.
Density will increase, static temperature will increase.
Density will increase, static temperature will decrease.
Which statement about a jet transport aeroplane is correct during take-off with the cg at the
forward limit and the trimmable horizontal stabiliser (THS) positioned at the maximum
allowable aeroplane nose down position?
445
The rotation will require extra stick force.
If the THS position is just within the limits of the green band, the take off warning system will be activated.
Early nose wheel raising will take place.
Rotation will be normal.
When flutter damping of control surfaces is obtained by mass balancing, these weights will
be located with respect to the hinge of the control surface:
446
in front of the hinge.
below the hinge.
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above the hinge.
behind the hinge.
How can the designer of an aeroplane with straight wings increase the static lateral
stability?
447
By increasing the aspect ratio of the vertical stabiliser, whilst maintaining a constant area.
By increasing anhedral.
By fitting a ventral fin (a fin at the under side of the aeroplane).
By applying wing twist.
Positive static longitudinal stability means that a:448
nose-down moment occurs after encountering an up-gust.
nose-up moment occurs with a speed change at constant angle of attack.
nose-down moment occurs with a speed change at constant angle of attack.
nose-up moment occurs after encountering an up-gust.
Which statement in respect of a trimmable horizontal stabiliser is correct?449
Because take-off speeds do not vary with centre of gravity location, the need for stabiliser adjustment is dependant on flap position only.
An aeroplane with a forward cg requires the stabiliser leading edge to be higher than for one with an aft cg in the same trimmed condition.
An aeroplane with a forward cg requires the stabiliser leading edge to be lower than for one with an aft cg in the same trimmed condition.
At the forward C.G. limit , stabiliser trim is adjusted fully nose down to obtain maximum elevator authority at rotation during take-off.
Which definition of propeller parameters is correct?450
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.
The angle of attack for a propeller blade is the angle between the blade chord line and the:451
direction of propeller axis.
aeroplane heading.
local air speed vector.
principal direction of the propeller blade.
Given two identical aeroplanes with wing mounted engines, one fitted with jet engines and
the other with counter rotating propellers, what happens following an engine failure?
452
More roll tendency for the propeller aeroplane.
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The same yaw tendency for both aeroplanes regardless of left or right engine failure.
The same roll tendency for both aeroplanes.
Less roll tendency for the propeller aeroplane.
The stall speed (IAS) will change according to the following factors:453
May increase when the cg moves forward, with higher altitude and due to the slipstream from a propeller on an engine located forward of the wing
Will increase in a turn, higher temperature and will increase when the cg moves aft
May increase with altitude, especially high altitude, will increase during icing conditions and will increase when the cg moves forward
Will increase with increased load factor, more flaps and increased bank angle in a turn
The stalling speed in IAS will change according to the following factors:454
Increase with increased load factor, more flaps but will not increase due to the bank angle in a turn
Increase during turn, increased mass and forward c.g. location
Decrease in a forward c.g. location, higher altitude and due to the slip stream from a propeller on an engine located forward of the wing
Increase with increased load factor, icing conditions and an aft c.g. location
The stalling speed in IAS will change according to the following factors:455
Will increase with increased load factor, icing conditions and more flaps
Will decrease with a forward c.g. location, lower altitude and due to the slip stream from a propeller on an engine located forward of the wing
May increase during turbulence and will always increase when banking in a turn
Will increase during turn, increased mass and an aft c.g. location
Which of the following statements is true?456
Flight in severe turbulence may lead to a stall and/or structural limitations being exceeded
Flap extension in severe turbulence at constant speed increases both the stall speed and the structural limitation margins
By increasing the flap setting in severe turbulence at constant speed the stall speed will be reduced and the risk for exceeding the structural limits will be decreased
Flap extension in severe turbulence at constant speed moves the centre of pressure aft, which increases the structural limitation margins
A conventional stabiliser on a stable aeroplane in a normal cruise condition:
1 - always provides negative lift.
2 - contributes to the total lift of the aeroplane.
3 - may stall before the wing, in icing conditions, with large flap settings, unless adequate
design and/or operational precautions are taken.
4 - is necessary to balance the total pitch moment of the aeroplane.
Which of the following lists all the correct statements ?
457
1, 3 and 4
1 and 3
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2, 3 and 4
1 and 4
Which statements are correct for a straight steady climb?
1 - lift is less than weight.
2 - lift is greater than weight.
3 - load factor is less than 1.
4 - load factor is greater than 1.
5 - lift is equal to weight.
6 - load factor is equal to 1.
Which of the following lists all the correct statements ?
458
1 and 6
1 and 3
2 and 4
5 and 6
Given an initial condition in straight and level flight with a speed of 1.4 VS. The maximum
bank angle attainable without stalling in a steady co-ordinated turn, whilst maintaining
speed and altitude, is approximately:
459
30°.
32°.
60°.
44°.
A 50 ton twin engine aeroplane performs a straight, steady, wings level climb. If the
lift/drag ratio is 12 and the thrust is 60 000N per engine, the climb gradient is: (assume g =
10m/s²)
460
15.7%.
3.7%.
24%.
12%.
An aeroplane in straight and level flight is subjected to a strong vertical gust. The point on
the wing, where the instantaneous variation in wing lift effectively acts is known as the:
461
aerodynamic centre of the wing.
centre of thrust.
centre of gravity.
neutral point.
In a straight steady descent, which of the following statements is correct ?462
Lift is less than weight, load factor is less than 1.
Lift is equal to weight, load factor is less than 1.
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Lift is equal to weight, load factor is equal to 1.
Lift is less than weight, load factor is equal to 1.
VLE is defined as the:463
maximum landing gear extended speed.
maximum speed at which the landing gear may be extended or retracted.
maximum flap extended speed.
maximum authorised speed.
When Fowler type trailing edge flaps are extended at a constant angle of attack, the
following changes will occur:
464
CL increases and the centre of pressure moves forward.
CL increases and CD remains constant.
CL and CD increase.
CD decreases and the centre of pressure moves aft.
An aeroplane has a stall speed of 100 kt at a mass of 1000 kg. If the mass is increased to
2000 kg, the new value of the stall speed will be:
465
123 kt.
141 kt.
200 kt.
150 kt.
When an aeroplane performs a straight steady climb with a 20% climb gradient, the load
factor is equal to:
466
0.83.
1.
0.98.
1.02.
In a convergent tube with an incompressible sub-sonic airflow, the following pressure