Cada pergunta deste Quiz é cronometrada.
The ISA
assumes a standard day.
is taken from the equator
is taken from 45 degrees latitude
At higher altitudes as altitude increases, pressure
decreases at constant rate.
decreases exponentially
increases exponentially
When the pressure is half of that at sea level, what is the altitude?.
12,000 ft.
18,000 ft.
8,000 ft.
If gauge pressure on a standard day at sea level is 25 PSI, the absolute pressure is.
39.7 PSI.
10.3 PSI.
43.8 PSI.
Pressure decreases.
inversely proportional to temperature.
proportionally with a decreases in temperature.
Pressure and temperature are not related.
As air gets colder, the service ceiling of an aircraft.
reduces.
increases.
remains the same.
What is sea level pressure?.
1012.3 mb.
1013.2 mb.
1032.2 mb.
How does IAS at the point of stall vary with height?.
It decreases.
It is practically constant.
It increases.
What is the lapse rate with regard to temperature?
4°C per 1000 ft.
1.98°C per 1000 ft.
1.98°F per 1000 ft.
Standard sea level temperature is.
20 degrees Celsius
0 degrees Celsius.
15 degrees Celsius.
As altitude increases, pressure.
decreases at constant rate
Lapse rate usually refers to.
Density.
Pressure
Temperature
Temperature above 36,000 feet will.
increase exponentially
decrease exponentially
remain constant
With increasing altitude pressure decreases and.
temperature decreases at the same rate as pressure reduces.
temperature decreases but at a lower rate than pressure reduces
temperature remains constant to 8000 ft
What is the temperature in comparison to ISA conditions at 30,000ft?.
60°C.
0°C
45°C.
At what altitude is the tropopause?.
36,000 ft.
57,000 ft.
63,000 ft.
What approximate percentage of oxygen is in the atmosphere?.
12%.
21%.
78%.
Which has the greater density?.
Air at low altitude.
Air at high altitude.
It remains constant.
At what altitude does stratosphere commence approximately?.
Sea level.
A pressure of one atmosphere is equal to.
14.7 psi.
1 inch Hg.
100 millibar.
The millibar is a unit of.
atmospheric temperature
pressure altitude.
barometric pressure.
With an increase in altitude under I.S.A. conditions the temperature in the troposphere.
remains constant.
decreases.
A barometer indicates.
pressure
density
temperature.
The amount of water vapour capacity in the air (humidity holding capacity of the air) is.
greater on a colder day, and lower on a hotter day
doesn't have a significant difference.
greater on a hotter day and lower on a colder day
Which condition is the actual amount of water vapour in a mixture of air and water?.
Relative humidity.
Absolute humidity
Dew point.
Which will weigh the least?.
98 parts of dry air and 2 parts of water vapour
50 parts of dry air and 50 parts of water vapour
35 parts of dry air and 65 parts of water vapour.
Which is the ratio of the water vapour actually present in the atmosphere to the amount that would be present if the air were saturated at the prevailing temperature and pressure?.
Relative humidity
The speed of sound in the atmosphere
changes with a change in pressure.
varies according to the frequency of the sound.
changes with a change in temperature.
Which statement concerning heat and/or temperature is true?.
Temperature is a measure of the kinetic energy of the molecules of any substance.
Temperature is a measure of the potential energy of the molecules of any substance.
There is an inverse relationship between temperature and heat.
What is absolute humidity?.
The temperature to which humid air must be cooled at constant pressure to become saturated.
The actual amount of the water vapour in a mixture of air and water.
The ratio of the water vapour actually present in the atmosphere to the amount that would be present if the air were saturated at the prevailing temperature and pressure.
The temperature to which humid air must be cooled at constantpressuretobecome saturated is called.
relative humidity.
dew point.
absolute humidity.
Density changes with altitude at a rate.
of 2kg/m3 per 1000 ft
which changes with altitude.
which is constant until 11 km.
Above 65,800 ft temperature.
decreases by 1.98°C up to 115,000 ft.
remains constant up to 115,000 ft.
increases by 0.303°C up to 115,000 ft.
At sea level, ISA atmospheric pressure is.
14.7 kPa.
10 Bar
14.7 PSI.
On a very hot day with ambient temperature higher than ISA, the pressure altitude is 20,000 ft. How much will the density altitude be?.
the same
greater than 20,000ft
less than 20,000ft
The atmospheric zone where the temperature remains fairly constant is called the.
Stratosphere.
Ionosphere.
Troposphere.
In the ISA the height of the tropopause is
11,000 feet.
11,000 metres
36,000 metres
In the ISA the sea level pressure is taken to be.
14 PSI.
1.013 mb
In the ISA the temperature lapse rate with altitude is taken to be :
dependent on pressure and density changes.
linear.
non linear.
Put in sequence from the ground up
tropopause, stratosphere, troposphere.
tropopause, troposphere, stratosphere.
troposphere, tropopause, stratosphere.
The International Standard Atmosphere can be described as.
the atmosphere at 45 degrees north latitude.
the atmosphere at the equator with certain conditions
the atmosphere which can be used Worldwide to provide comparable performance results.
The temperature lapse rate below the tropopause is.
1°C per 1000 ft.
2°C per 1000 ft.
3°C per 1000 ft.
Above the tropopause air pressure
decreases at a constant rate.
decreases exponentially.
Which of the following is correct?.
Absolute pressure + Atmospheric pressure = Gauge pressure
Absolute pressure = Gauge pressure + Atmospheric pressure
Atmospheric pressure = Absolute pressure + Gauge pressure
As the altitude increases what happens of the ratio of Nitrogen to Oxygen?.
Increases.
Decreases.
Stays the same.
What happens to the density of air as altitude is increased?.
An aircraft is travelling at a speed of 720 nautical miles per hour. To calculate speed in MPH you.
divide by 0.83.
multipy by 0.83
multiply by 1.15.
Lift on a delta wing aircraft
increases with an increased angle of incidence (angle of attack).
does not change with a change in angle of incidence (angle of attack).
decreases with an increase in angle of incidence (angle of attack).
The CofP is the point where.
the lift can be said to act.
the three axis of rotation meet.
all the forces on an aircraft act
When an aircraft experiences induced drag.
air flows under the wing span wise towards the root and on top of the wing span wise towards the tip.
Neither a) or b) since induced drag does not caused by span wise flow.
air flows under the wing span wise towards the tip and on top of the wing span wise towards the root.
At stall, the wingtip stagnation point.
doesn’t move
moves toward the lower surface of the wing.
moves toward the upper surface of the wing.
The rigging angle of incidence of an elevator is.
the angle between the bottom surface of the elevator and the longitudinal datum.
the angle between the bottom surface of the elevator and the horizontal in the rigging position.
the angle between the mean chord line and the horizontal in the rigging position.
Which of the following is true?.
Lift acts at right angles to the relative airflow and weight acts vertically down.
Lift acts at right angles to the wing chord line and weight acts vertically down.
Lift acts at right angles to the relative air flow and weight acts at right angles to the aircraft centre line.
The vertical fin of a single engined aircraft is.
parallel with the longitudinal axis but not the vertical axis.
parallel with both the longitudinal axis and vertical axis.
parallel with the vertical axis but not the longitudinal axis.
What happens to air flowing at the speed of sound when it enters a converging duct?.
Velocity increases, pressure and density decreases.
Velocity, pressure and density increase.
Velocity decreases, pressure and density increase
As the angle of attack of an airfoil increases the centre of pressure.
remains stationary.
moves aft.
moves forward.
Vapour trails from the wingtips of an aircraft in flight are caused by.
low pressure above the wing and high pressure below the wing causing vortices.
low pressure above the wing and high pressure below the wing causing a temperature rise.
high pressure above the wing and low pressure below the wing causing vortices.
The chord line of a wing is a line that runs from.
the centre of the leading edge of the wing to the trailing edge.
half way between the upper and lower surface of the wing.
one wing tip to the other wing tip.
The angle of incidence of a wing is an angle formed by lines.
parallel to the chord line and longitudinal axis
parallel to the chord line and the vertical axis.
parallel to the chord line and the lateral axis
The centre of pressure of an aerofoil is located.
30 - 40% of the chord line forward of the leading edge
50% of the chord line back from the leading edge.
30 - 40% of the chord line back from the leading edge
Compressibility effect is.
drag associated with the form of an aircraft.
the increase in total drag of an aerofoil in transonic flight due to the formation of shock waves.
drag associated with the friction of the air over the surface of the aircraft.
A high aspect ratio wing will give.
high profile and low induced drag.
low profile and high induced drag.
low profile and low induced drag.
Aerofoil efficiency is defined by.
lift over drag.
lift over weight.
drag over lift.
The relationship between induced drag and airspeed is, induced drag is.
directly proportional to the square of the speed.
directly proportional to speed.
inversely proportional to the square of the speed.
What is the definition of Angle of Incidence?.
The angle the underside of the mainplane or tailplane makes with the horizontal
The angle the underside of the mainplane or tailplane makes with the longitudinal datum line.
The angle the chord of the mainplane or tailplane makes with the horizontal.
What is Boundary Layer?.
Separated layer of air forming a boundary at the leading edge
Sluggish low energy air that sticks to the wing surface and gradually gets faster until it joins the free stream flow of air.
Turbulent air moving from the leading edge to trailing edge.
What is the collective term for the fin and rudder and other surfaces aft of the centre of gravity that helps directional stability?
Empennage.
Fuselage surfaces.
Effective keel surface
A decrease in incidence toward the wing tip may be provided to
prevent adverse yaw in a turn.
retain lateral control effectiveness at high angles of attack
prevent span wise flow in maneuvers.
For a given aerofoil production lift, whereP = pressure and V = velocity.
P1 is greater than P2, and V1 is less than V2.
P1 is greater than P2, and V1 is greater than V2.
P1 is less than P2 and V1 is greater than V2.
Low wing loading
increases stalling speed, landing speed and landing run.
increases lift, stalling speed and maneuverability
decreases stalling speed, landing speed and landing run.
As a general rule, if the aerodynamic angle of incidence (angle of attack) of an aerofoil is slightly increased, the centre of pressure will.
move towards the tip.
move forward towards the leading edge.
never move.
The 'wing setting angle' is commonly known as.
angle of dihedral
angle of incidence.
angle of attack.
When does the angle of incidence change?.
It never changes
When the aircraft attitude changes
When the aircraft is ascending or descending
As the angle of attack decreases, what happens to the centre of pressure?.
It moves rearwards.
Centre of pressure is not affected by angle of attack decrease.
It moves forward
A decrease in pressure over the upper surface of a wing or aerofoil is responsible for.
approximately 2/3 (two thirds) of the lift obtained.
approximately 1/2 (one half) of the lift obtained
approximately 1/3 (one third) of the lift obtained.
Which of the following types of drag increases as the aircraft gains altitude?.
Interference drag.
Parasite drag.
Induced drag.
The layer of air over the surface of an aerofoil which is slower moving, in relation to the rest of the airflow, is known as.
none of the above
camber layer.
boundary layer.
What is a controlling factor of turbulence and skin friction?.
Countersunk rivets used on skin exterior.
Aspect ratio.
Fineness ratio.
If the C of G is aft of the Centre of Pressure.
when the aircraft yaws the aerodynamic forces acting forward of the Centre of Pressure.
changes in lift produce a pitching moment which acts to increase the change in lift.
when the aircraft sideslips, the C of G causes the nose to turn into the sideslip thus applying a restoring moment.
The upper part of the wing in comparison to the lower.
develops less lift
develops the same lift.
develops more lift.
What effect would a forward CG have on an aircraft on landing?.
Increase stalling speed.
Reduce stalling speed.
No effect on landing.
QNH refers to
quite near horizon
setting the altimeter to zero.
setting the mean sea level atmospheric pressure so an altimeter reads the aerodrome altitude above mean sea level.
QNE refers to
setting the mean sea level atmospheric pressure in accordance with ICAO standard atmosphere i.e. 1013 millibars.
Setting an altimeter to read aerodrome altitude above sea level
quite new equipment
An aspect ratio of 8 : 1 would mean.
span 64, mean chord 8.
mean chord 64, span 8
span squared 64, chord 8.
QFE is.
airfield pressure.
difference between sea level and airfield pressure.
sea level pressure.
For any given speed, a decrease in aircraft weight, the induced drag will.
decrease
remain the same
increase.
The amount of lift generated by a wing is.
greatest at the tip.
constant along the span
greatest at the root.
Induced Drag is
greatest towards the tip and downwash decreases from tip to root
greatest towards the wing tip and downwash is greatest towards the root
greatest towards the wing root and downwash is greatest at the tip
Induced Drag is.
never equal to profile drag.
equal to profile drag at Vmd
equal to profile drag at stalling angle
