Anúncios
1
On a swept wing aeroplane at low airspeed, the "pitch up" phenomenon:
Never occurs, since a swept wing is a 'remedy' to pitch up
is caused by boundary layer fences mounted on the wings.
is caused by wingtip stall.
Is caused by extension of trailing edge lift augmentation devices
2
Which one of the following statements about the lift-to-drag ratio in straight and level flight is correct?
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 equal to the aircraft weight
The highest value of the lift / drag ratio is reached when the lift is zero
The lift / drag ratio always increases as the lift decreases
3
Induced drag is created by the:
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.
propeller wash blowing across the wing.
4
Positive static stability of an aeroplane means that following a disturbance from the equilibrium condition:
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 increasing amplitude.
the tendency is to move with an oscillatory motion of decreasing amplitude.
5
Which statement on dynamic longitudinal stability of a conventional aeroplane is correct?
Damping of the short period oscillation is normally very weak.
Damping of the phugoid is normally very weak.
Period time of the phugoid is normally 5 s.
Speed remains constant during one period of the phugoid
6
When the cg position is moved forward, the elevator deflection for a manoeuvre with a given load factor greater than 1 will be:
smaller
larger
dependent on trim position
unchanged
7
Which combination of design features is known to be responsible for deep stall?
Swept back wings and a T-tail.
Straight wings and aft fuselage mounted engines.
Swept back wings and wing mounted engines.
Straight wings and a T-tail.
8
After take-off the slats (when installed) are always retracted later than the flaps. Why?
Because SLATS EXTENDED gives a large decrease in stall speed with relatively
less drag.
Because SLATS EXTENDED provides a better view from the cockpit than FLAPS
EXTENDED.
Because VMCA with SLATS EXTENDED is more favourable compared with the
FLAPS EXTENDED situation
Because FLAPS EXTENDED gives a large decrease in stall speed with relatively
less drag
9
Given an aeroplane with a propeller turning clockwise as seen from behind, the torque effect during the take off run will tend to:
roll the aeroplane to the right.
pitch the aeroplane nose up.
pitch the aeroplane nose down.
roll the aeroplane to the left.
10
The type of stall that has the largest associated angle of attack is:
a deep stall
an accelerated stall.
a shock stall
a low speed stall.
11
The effects of very heavy rain (tropical rain) on the aerodynamic characteristics of an aeroplane are:
decrease of CLmax and increase of drag.
increase of CLmax and decrease of drag.
increase of CLmax and increase of drag.
decrease of CLmax and decrease of drag
12
The speed of sound is determined only by:
humidity
density
temperature
pressure
13
A laminar boundary layer is a layer, in which:
no velocity components exist, normal to the surface.
the velocity is constant
the vortices are weak
the temperature varies constantly
14
The lift force, acting on an aerofoil: (no flow separation)
is maximum at an angle of attack of 2 degrees.
increases, proportional to the angle of attack until 40 degrees.
is mainly caused by overpressure at the underside of the aerofoil.
is mainly caused by suction on the upperside of the aerofoil.
15
The induced drag:
increases as the magnitude of the tip vortices decreases.
has no relation to the lift coefficient
increases as the aspect ratio increases.
increases as the lift coefficient increases.
16
The critical angle of attack:
increases if the CG is moved forward.
changes with an increase in gross weight
remains unchanged regardless of gross weight
decreases if the CG is moved af
17
The relationship between induced drag and the aspect ratio is:
there is no relationship.
induced drag = 1.3 aspect ratio value
a decrease in the aspect ratio increases the induced drag.
an increase in the aspect ratio increases the induced drag.
18
The induced angle of attack is:
the angle between the local flow at the wing and the horizontal tail.
the angle by which the flow over the wing is deflected when landing flaps are set.
caused by the fuselage and is greatest at the wing root
the angle by which the relative airflow is deflected due to downwash
19
Slat or flap asymmetry occurring after either extension or retraction, may have an effect on controllability since:
slat asymmetry causes a yawing moment, whereas flap asymmetry causes a large
rolling moment.
slat and flap asymmetry both cause a large rolling moment
slat and flap asymmetry both cause a large yawing moment.
slat asymmetry causes a large rolling moment, whereas flap asymmetry causes a
large yawing moment
20
Which of the following situations leads to a decreasing stall speed (IAS)?
increasing load factor.
increasing altitude.
increasing air density.
decreasing weight.
