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WorksheetsAirframe còn lại
Total questions: 106
Worksheet time: 53mins
Main and nose wheel bays are:
pressurized
unpressurized
conditioned
different, with the mains being unpressurized and the nose pressurized
Normal maximum negative differential pressure is:
when atmospheric pressure exceeds cabin pressure by the amount permitted by the system controls
where the cabin pressure falls below aircraft altitude pressure at which time the inward relief valve opens
when the cabin pressure exceeds the atmospheric pressure by 0.5 psi
the pressure at which the duct relief valve is set to operate
When would the negative differential limit be reached/exceeded?
Rapid descent when AC descends below cabin altitude
During ground pressure testing
Rapid ascent when aircraft climbs
When changing to manual operation
A/C in level flight: if cabin altitude increases, pressure diff:
increases
decreases
remains the same
nil
In level pressurized flight what does the outflow valve do?
Close
Adjust to provide constant flow, and is normally partially open
Open to increase air conditioning
Adjust to provide maximum flow, and is normally almost closed
In a turbo-compressor or bootstrap system the cooling air is:
ram air
engine by pass air
cabin air
compressor air
The rate of change of cabin pressure should be kept to the minimum. This is more important:
in descent
in climb
in periods when the dehumidifier is in use
in cruise
A cabin humidifier is used:
on the ground in conditions of low relative humidity
at high altitude
at low altitude
on the ground in high ambient temperatures
Fatigue life of the fuselage is based on the:
number of pressurization cycles
number of explosive decompressions
number of landings only
number of cycles at maximum differential
If the forward oil seal in an axial flow compressor fails, cabin air will be:
contaminated
unaffected
'b' is only correct if synthetic oil is used
'a' will be correct only if the aircraft is inverted
Rate of change of cabin altitude is shown on a:
special gauge
aircraft VSI
cabin pressure controller
gauge reading a percentage of Max Diff Pressure
Cabin discharge valve (pneumatic) is supplied with:
air data computer output information
cabin and static pressure
cabin pressure, static and air speed information
cabin pressure only
What is the purpose of the duct relief valve?
To protect the undercarriage bay
To ensure the compressor pressure is regulated
To prevent damage to the ducts
To relieve excess pressure to compressor return line
What system is installed to control the air conditioning?
Emulsifier and water extractor
Impingement type dehydrator and humidifier
Dehydrator only
Humidifier only
How is the (charge) air cooled in a bootstrap (turbo-compressor) system?
By expanding over turbine
By expanding over turbine driving compressor
Via an air cooled radiator
By passing it through the fuel heater
At the max differential phase, the discharge phase is:
open
closed
under the control of the rate capsule
partly open
What is the purpose of inward relief valves?
To prevent negative differential
To back up the duct relief valve
To allow positive pressure to be bled off in an emergency
To back up the outflow valve
On a ground pressurization test, if the cabin suffers a rapid de-pressurization:
the temperature will rise suddenly
water precipitation will occur
damage to hull may occur
duct relief valve may jam open
A heat exchanger functions by:
combining ram and charge air
mixing the various vapours inside the heat exchanger
passing charge air through ducts and cool air around ducts
removing the static charge
Maximum differential pressure:
is the maximum authorized pressure difference between the inside of the fuselage and the atmospheric ambient pressure
is the absolute pressure provided by the vacuum pump
is the pressure loss over a given time limit
is the absolute pressure the cabin pressure ducting is designed to carry
A humidifier is fitted to:
extract the moisture content in the air
filter the air
increase the moisture content in the air when operating at high altitude
to ensure the cabin air is saturated at high altitude
If the discharge or outflow valve closes:
the duct relief valve will take control
the inward relief valve would assume control
the safety valve would limit the positive pressure difference
the safety relief valve would limit the negative pressure difference
Air for conditioning and pressurization is taken from:
the engine compressor or cabin compressor
the engine by pass duct or thrust reverse by pass duct
the engine compressor or ram turbine
the engine turbine or cabin compressor
Safety valves are biased:
inwards
outwards
in the direction sensed by the SVC
neither a nor b
Cabin compressors:
increase their flow in cruise conditions
decrease their flow in cruise conditions
increase their flow in proportion to increases of altitude differential pressure and reduction in engine rpm in order to maintain the mass flow
deliver minimum air at sea level via the cold air unit
In a pressurization circuit the sequence of operation is for the:
inward relief valve to open before the safety valve
outflow valve to operate before the safety valve
outflow valve to operate after the safety valve
outflow valve to operate the same time as the safety valve
In the cruise at 30 000 ft the cabin altitude is adjusted from 4000 ft to 6000 ft:
cabin differential will increase
cabin differential will not be affected
cabin differential will decrease
nil.
An aircraft climbs from sea level to 16 000 ft at 1000 ft per min, the cabin pressurization is set to climb at 500 ft per min to a cabin altitude of 8000 ft. The time taken for the cabin to reach 8000 ft is:
the same time as it takes the aircraft to reach 16 000 ft
half the time it takes the aircraft to reach 16 000 ft
twice the time it takes the aircraft to reach 16 000 ft
three times the time it takes the aircraft to reach 16 000 ft
The aircraft inhibiting switch connected to the A/C landing gear:
allows the aircraft to be pressurized on the ground
stops pressurizing on the ground and ensures that there is no significant pressure differential
ensures that the discharge valve is closed
cancels out the safety valve on the ground
Negative differential is limited by:
dump valve
inward relief valve
outflow valve
safety valve
To maintain a steady and constant airflow regardless of altitude or cabin pressure:
a duct relief valve is fitted
a venturi device is fitted
a mass flow controller is fitted
a thermostatic relief valve is fitted
The term 'pressurization cycle' means:
air introduced into a fuselage under pressure only
air introduced into a fuselage under pressure until the time the air is released
air discharged from the fuselage, above 15 psi
the frequency in Hz the pressure cycles from the rootes blowers enter the fuselage
Inward Relief Valves operate:
in conjunction with the cabin pressure controller when there is a negative diff
in conjunction with the cabin altitude selector when there is negative diff
when manually selected during the emergency descent procedure
automatically when there is a negative diff
Safety valves operate:
at higher than maximum differential
as soon as initiation takes place
at a lower diff than a discharge valve
at a set value, which is selected
Ditching Cocks are operated:
automatically when the soluble plugs dissolve
to shut all outflow valves
to direct pressure into flotation bags
for rapid depressurization
Duct Relief Valves operate when:
excessive pressure builds up in the air conditioning system supply ducts
to keep cabin pressure close to ambient pressure
to prevent the floor from collapsing should baggage door open
the cooling modulator shutters reach the optimized position
During a normal pressurized cruise, the discharge valve position is:
at a position pre-set before take-off
partially open
open until selected altitude is reached
closed until selected altitude is reached
A dump valve:
automatically opens when fuel is dumped
is controlled manually
is opened automatically when the safety valve opens
is controlled by the safety valve integrating line
When air is pressurized the % of oxygen:
increases
decreases
remains the same
nil
If pressure is manually controlled:
an extra member is required to monitor system operation
the climb rate would be maintained automatically
climb rate could not be maintained
care should be taken to ensure climb/descent rates are safe
An aircraft is prevented from pressurizing on the ground by:
the auto deflating valve on the main oleos
inhibiting microswitches on the landing gear
inhibiting microswitches on the throttles
the pressure control master switch
If the pressurization air is passed over the cold air unit compressor it:
increases the charge air temperature
decreases the charge air temperature
decreases the charge air pressure
makes no change to the charge air condition
If the cabin pressure increases in level flight does the cabin VSI shows:
rate of climb
no change unless the aircraft climbs
rate of descent
nil
The term pressure cabin is used to describe:
pressurization of the flight deck only
the ability to pressurise the aircraft to a higher than ambient pressure
the passenger cabin on an airliner
the ability to maintain a constant pressure differential at all altitudes
A pressurization system works by:
essentially constant input mass flow and variable output
essentially constant output mass flow and variable input
does not start until an altitude of 8000 ft has been reached
supplying hot gases from the engine exhaust unit to the mass flow control system
When air is pressurized by an engine driven compressor, it is also:
moisturized
heated
cooled
the temperature is not affected
Without added oxygen the time of useful consciousness at 30 000 ft is approximately:
twenty seconds
eighty seconds
one to two minutes
six minutes
Without added oxygen the time of useful consciousness at 40 000 ft is approximately:
twenty seconds
three minutes
eighty seconds
six minutes
The maximum altitude without oxygen at which flying efficiency is not seriously impaired is:
10 000 ft
17 500 ft
25 000 ft
30 000 ft
In a pressure demand oxygen system:
each member of the crew has a regulator
each member of the crew has a continuous oxygen supply
oxygen is supplied with a continuous pressure flow
oxygen demand will cause the pressure to rise
In a continuous flow oxygen system, oxygen is supplied:
only when the mask is plugged into the socket connection
only on passenger inhalation through the mask
only when the cabin altitude is above 18 000 ft
only when the supply has been regulated by the pilot
In a diluter demand system, selection of emergency on this regulator will result in:
air mix supplied at emergency pressure
100% oxygen supply as called for by the user
100% oxygen at positive pressure
100% oxygen continuous flow at positive pressure
If the aircraft suffers a decompression passenger oxygen masks:
are released by the passengers
automatically drop to a half-hung (ready position)
are handed out by the cabin staff
must be removed from the life jacket storage
Oxygen cylinders are normally charged to:
1000 psi
1200 psi
1800 psi
2000 psi
Rate of flow of oxygen is given in:
litres/minute
pounds/minute
litres/second
kilos/hour
The colour of American and European oxygen cylinders is:
red
blue
green
brown
Dangerous pressure rise in oxygen cylinders:
is relieved by a thermostat
is relieved by under pressurizing the bottle
is relieved by a bursting disc
is controlled by a thermal relief valve
To leak test an oxygen system use:
fairy liquid and de-ionized water
thin oil
acid free soap and distilled water
acid free soap and water
Lubrication of an oxygen component thread is by:
soap water
grease
oil
graphite
Satisfactory operation of the oxygen system is indicated by:
flow indicators
lack of anoxia
aural reassurance
pressure indicators
If the pressurization system fails and the cabin starts to climb, then at 14 000 ft oxygen will be available to the passengers by:
the stewardess who will hand out masks
the passengers grabbing a mask from the overhead lockers
portable oxygen bottles located in the seat backs
masks automatically ejected to a half-hung position
When air is pressurized the % of oxygen:
increases
decreases
remains the same
nil
In an emergency chemically produced oxygen is supplied for a given period by:
sodium chlorate, iron power, an electrical firing system and a filter
potassium chlorate, iron powder, an electrical firing system and a filter
sodium chlorate, iron powder which is chemically activated by air and then filtered
sodium chlorate and an electrical firing system
Passenger oxygen masks will present:
only when the cabin altitude reaches 14 000
only if selected by the crew
only if selected by the cabin staff
if selected manually / electrically / barometrically
The charged pressure of a portable oxygen cylinder is normally:
500 psi
1200 psi
1800 psi
3000 psi
With the control knob set to high, a 120 litreportable bottle will provide oxygen for a period of:
60 mins
30 mins
12 mins
3 mins
At what altitude will the diluter-demand oxygen regulator provide 100% pure oxygen:
10 000 ft
14 000 ft
24 000 ft
34 000 ft
A flow indicator fitted to an oxygen regulator indicates:
that exactly the correct amount of oxygen is being used by the crew member
that oxygen is flowing through the regulator
that the crew member is correctly connected to the regulator
that the system pressure reducing valve is supplying the correct pressure to the regulator
What is the approximate time of useful consciousness when hypoxia develops at the specified altitudes? 20 000 ft, 30 000 ft
2-3 min, 10-15 sec
10 min, 2 min
30 min, 90-60 secs
40 min, 5 min
What is the effect on cabin temperature of a rapid de-compression at 30 000 ft?
Sudden and extreme drop
Insignificant change over the first 2 minutes
A gradual decrease to ambient over a period of about 10 minutes if the cabin heating ceases
A gradual decrease to ambient temperature over a period of about 30 minutes if cabin heating continues
Susceptibility to hypoxia is increased by:
heat
noise
smoking
under-breathing
What is the approximate cabin altitude above which you must breath 100% oxygen if you are to maintain an alveolar partial pressure equal to that at sea level?
26 000 ft
30 000 ft
34 000 ft
38 000 ft
Baffles are fitted in aircraft fuel tanks:
to assist in correct fuel distribution
to prevent fuel surging during aircraft manoeuvres
to prevent the static build-up in the tank during refuelling
to channel fuel to the vent valve
A power failure to a capacitive fuel contents system would cause the gauge to:
show full scale deflection high
fluctuate between high and low readings
remain fixed on the last contents noted before failure
show full scale deflection low
A fuel booster pump, besides pumping fuel to the engine, can also be utilized to:
jettison and transfer fuel
jettison and heat the fuel
transfer and heat the fuel
transfer and recycle the fuel
During fuel jettison, the aircraft is protected against running out of fuel by:
high level float switches
preset jettison quantity switches
the crew remaining alert
low level float switches
To indicate that a refuelling bowser carries JET A1 aviation kerosene:
yellow and black stripes are marked on the refuelling hose
JET A1 would be painted in 30 cm high symbols on the side of the container
JET A1 is printed in white on a black background label positioned prominently on the vehicle
the driver wears a straw yellow water and fuel proof jacket
Adjustments may have to made to an aircraft's engine fuel system if it has been refuelled with JET B instead of its normal JET A1 fuel, these adjustments are to cater for:
the change in the specific gravity of the fuel
the change in the calorific value of the fuel
the change in the viscosity of the fuel
the lack of HITEC lubricant in the fuel
The differences between AVGAS 100 and AVGAS 100LL are: Colour Anti-knock value
Same Same
Same Different
Different Same
Different Different
The aircraft cannot be refuelled while:
a ground power unit is operating on the ramp
passengers are walking through the refuelling zones
passengers are boarding
the APU is running
The disadvantage of refuelling the aircraft to 'tanks full' the night before a departure in the heat of the day is that:
the change in the specific gravity may cause the aircraft to be overweight
the change in the volume of the fuel may cause it to spill through the vent system
the change in calorific value may reduce engine power to below sufficient
the rpm governor will be rendered inoperative
An aircraft using MOGAS:
is likely to be affected by detonation at cruise power
must have booster pumps fitted in the fuel tanks
is more likely to be affected by vapour locking and carburettor icing
will suffer from a loss of power during take-off
If a fuel sample appears cloudy or hazy, the most probable cause is:
water contamination
anti-microbiological additives
mixing different fuel grades
oil in the fuel
On an aircraft equipped with a compensated capacitance type fuel quantity indication system graduated to read in kg, the temperature increases just after the tanks are half filled with fuel. If the fuel expands by 10%, the gauges will show:
an increase of 10%
a decrease of 10% of the volume factored by the new specific gravity
a decrease
the same amount
The exhaust gases from the APU go into the refuelling zone. The APU:
must be switched OFF throughout the refuelling operation
can be started while refuelling is carried out.
must be started before fuelling is carried out, and can be run throughout the refuelling operation
can be started only after the refuelling operation has been terminated
De-fuelled fuel:
can only be used in domestic heating systems
can only be used by aircraft from the same operators fleet
must be put back into storage
cannot be re-used until its quality has been verified
The background colour scheme for fuelling system pipelines carrying the following fuels is: JET A1 AVGAS
Red Black
Black Red
Red Yellow
Yellow Red
AVGAS:
is coloured red for identification purposes
is coloured green if it is a leaded fuel and blue if it is a low lead fuel
has no artificial colouring and appears either clear or a straw yellow colour
can only be used in piston engines if oil is added to improve its anti-knock properties
Information relating to the use of MOGAS can be found in:
CAA General Aviation Safety Sense Leaflets
Advisory Information Circulars
NOTAM
CAA Airworthiness Publications
The fuel cross-feed valves are fitted in order to facilitate:
the use of fuel from any tank to any engine
refuelling when only one bowser is in use
isolation of the engine from the fuel system in the case of an engine fire
transfer of fuel between the main fuel tanks
Refuelling with passengers on board is not permissible:
on a fixed wing aircraft
if AVGAS is being used
if the aircraft has more than twenty seats and the ratio of cabin attendants to passengers is greater than 1:50 and it is a wide bodied jet
in any of the above cases
While refuelling with passengers on board, when a loading bridge is in use:
two sets of extra steps must be provided, one of which must be at the rear of the aircraft
the rear left or right door must be manned constantly by a cabin attendant ready for use as an emergency exit using the inflatable escape slide
ground servicing must not be carried out
catering and cleaning must not be carried out
Modern jet aircraft fuel tanks are pressurized:
by air from the engine compressor to prevent cavitation
by air from the air conditioning system to prevent cavitation
by ram air to prevent cavitation
by ram air to stabilize the boiling point
A 'wide-cut' fuel is:
more flammable than a kerosene type fuel
less volatile than a kerosene type fuel
coloured red for identification purposes
commonly used in civilian transport aircraft
The purpose of fitting baffles in fuel tanks is to:
prevent longitudinal movement of the fuel during acceleration
allow the booster pump to remain covered by fuel irrespective of the aircraft attitude
dampen lateral movement of the fuel in the wing tanks during a sideslip
maintain a pre-determined quantity of fuel in the outboard section of the wing tanks
Fuel is heated:
to stop cavitation in the High Pressure fuel pump
to maintain a constant viscosity
to prevent water contamination
to stop ice blocking the Low Pressure fuel filter
What is the function of a collector tank (feeder box)?
Prevent detonation during take-off
Prevent cavitation of the booster pumps
Prevent fuel surge due to extreme aircraft attitude
Allow suction feeding of the engine pump
Fuel tank booster pumps are:
centrifugal, low pressure
centrifugal, high pressure
gear type, low pressure
gear type, high pressure
The advantage of a capacitor type fuel contents gauging system is that the circuit:
responds to changes in specific gravity
compensates for high altitude flight
responds automatically to extremely low temperatures
compensates for aircraft attitude changes
The Low Pressure engine driven pump:
backs up in case the engine High Pressure pump fails
backs up in case of a double booster pump failure
assists in the refuelling operation if only low pressure refuelling systems are available
pressurizes the fuel tanks to assist flow to the booster pumps
The purpose of the fuel cooled oil cooler is to:
heat the oil and cool the fuel
heat the fuel and cool the oil
cool the oil
heat the fuel
If a fuel tank with a capacitive quantity system was filled with water instead of fuel, the gauge would indicate:
full scale low (zero)
it would indicate the same as if it were filled with fuel
full scale high (max)
it would freeze at the last known indication
AVTUR or JET A1:
varies in colour between clear and straw yellow
is a wide-cut fuel which is not normally used in civilian transport aircraft
is a gasoline type fuel with a high flash point
is a 97 octane fuel which prevents detonation in gas turbine engines
When using which of the following fuels can refuelling be carried out with passengers on board?
Avtag
Jet B
Wide-cut
Jet A1
With an increase in altitude the boiling point of fuel will:
stay the same
increase
decrease
increase up to FL80 then remain the same
When refuelling an aircraft:
the refuelling nozzle must be bonded to the fuel tank
the bonding plug must be connected to the earth terminal
the continuity between nozzle and hose must be infinity
only use plastic nozzles
