air systems Flashcards
when does the DUAL BLEED VALVE Amber Light illuminates ? what can this cause ?
APU bleed air valve ON
+
NG 1/2 bleed air switch ON
OR
APU bleed air valve ON
+
isolation valve OPEN
Possible backpressure of the APU
Thrust must be limited to IDLE
page 2.10.1
what happens when the ISOLATION Switch VALVE is on AUTO ?
if NG 1/2 Bleed Air Valve Switch is ON
+
L/R PACK Switch ON the ISOLATION VALVE
= closes automatically
if NG 1/2 Bleed Air Valve Switch is OFF
+
L/R PACK Switch OFF the ISOLATION VALVE
= opens automatically
page 2.10.1
what causes the WINGBODY OVERHEAT Amber Light to come on ?
overheat is cause by a bleed air duct leak
left light indicates overheat from:
- bleed air duct leak in left engine strut, or
- left inboard wing leading edge, or
- left air conditioning bay, or
- keel beam or
- APU bleed air duct
right light indicates overheat from:
- bleed air duct leak in right engine strut, or
- right inboard wing leading edge or
- right air conditioning bay
page 2.10.2
what is the difference between the WINGBODY OVERHEAT Amber Light Left to Right ?
left indicates overheat from the Keel Beam and APU bleed air duct, when right doesn’t
page 2.10.2
what happens when the ENGINE BLEED AIR switch is ON ?
engine bleed air will open when engine operating
page 2.10.2
what happens when the APU BLEED AIR switch is ON ?
APU bleed air will open when the APU is running
page 2.10.2
what causes the BLEED TRIP OFF Amber Light to come on ?
excessive engine bleed air temperature or pressure
page 2.10.2
when you press the TRIP RESET Switch do the tested systems stay open or closed during testing ?
open
page 2.10.2
what happens when the Left or Right PACKS Switch is in the AUTO position ?
- with both PACKS operating = LOW FLOW
- with only one PACK operating = HIGH FLOW
- with PACK operated by APU = HIGH FLOW
page 2.10.4
what happens when the Left or Right PACKS Switch is in the HIGH position ?
- HIGH FLOW
- HIGH FLOW when APU is ON
page 2.10.4
what causes the PACK TRIP OFF Amber Light to come on ?
PACK or PACKS have exceeded temperature or pressure
page 2.10.4
what happens when the PACK TRIP OFF Amber Light comes on ?
pack valve automatically closes and MIX VALVES drive full cold
page 2.10.5
in the Cabin Altitude Panel what does the Inner Scale read ?
cabin altitude in feet
page 2.10.6
in the Cabin Altitude Panel what does the Outer Scale read ?
differential pressure between Cabin and Ambient in PSI
page 2.10.6
when does the ALT HORN CUT OUT sound ?
when the Cabin Altitude reaches 10000ft
page 2.10.6
in the Cabin Pressurisation Panel what causes the AUTO FAIL Amber Light to come on ?
- if only AUTO FAIL light on = double controller failure
- if AUTO FAIL light on + ALTN Light on = single controller failure
page 2.10.7
what causes the OFF SCHED DESCENT Amber Light to come on ?
aircraft descended before reaching cruise altitude
page 2.10.8
what does the FLT ALT actually indicate ? and when should this altitude be set ?
CRZ ALT
to be set before T/O
page 2.10.8
what does the LAND ALT actually indicate ? and when should this altitude be set ?
Landing FIELD ALT
to be set before T/O
page 2.10.8
if on the FLT ALT and LAND ALT display you see either “8888 or - - - - -“ what does it mean ? and what should you do ?
DC Failure
- check CABIN ALT and CABIN PRESSURE
- if normal CABIN PRESS, system is not effected
page 2.10.8
if the FLT ALT and LAND ALT display is “BLANK” or “No Number? indicated what does this mean ?
the display is not working
if you can’t change the situation because the KNOB is not working then monitor the pressurisation system !!!
page 2.10.8
what should you be mindful of regarding the OUTFLOW VALVE Switch when on MANUAL Mode ?
it is spring loaded
page 2.10.9
where can the Bleed Air be supplied from ?
- engines
- APU
- external air cart
page 2.20.1
which systems rely on Bleed Air for their operation ?
- Air conditioning/pressurization
- Wing and engine thermal anti-icing
- Engine starting
- Hydraulic reservoirs pressurization
- Water tank pressurization
- Aspirated TAT probe
page 2.20.1
where is engine bleed air obtained from ?
from the 5th to 9th stage of the compressor section
page 2.20.1
what happens when 5th stage low pressure bleed air is insufficient for the bleed air system requirements ?
high stage valve opens to maintain adequate bleed air pressure
page 2.20.1
is during takeoff, climb, and most cruise conditions, low pressure bleed air from the 5th stage adequate ?
yes
page 2.20.1
because of the low pressure bleed air from the 5th stage is adequate during take off, climb and cruise does the stage valve open or remain close ?
the high stage valve remains closed because not needed
page 2.20.1
what is the aim of the Engine Bleed Air Valve ?
to act as a pressure regulator and shutoff valve
page 2.20.1
how is the Engine Bleed Air Valve activated and operated ?
DC activated
Pressure operated
page 2.20.1
when would the Engine Bleed Air Valve reduce bleed air outflow (closing) ?
in responds to high bleed air temperature
page 2.20.1
what causes the BLEED TRIP OFF Amber Light to come on ?
engine bleed air temperature or pressure exceeds a predetermined limit
page 2.20.1
what happens when the BLEED TRIP OFF Amber Light comes on ?
engine bleed air closes automatically
page 2.20.1
what does the Duct Pressure Transmitter indicate? and through what ?
bleed air pressure indications via the Bleed Air Duct Pressure Indicator
page 2.202
is the Duct Pressure Transmitter AC or DC operated ?
AC
page 2.20.2
are differences between L and R duct pressure on the bleed air duct pressure indicator considered normal ?
YES, as long as there is sufficient air for cabin pressurisation
page 2.20.2
what is the aim of the ISOLATION VALVE ?
isolates the left and right sides of the bleed air duct during normal operations
page 2.20.2
is the ISOLATION VALVE DC or AC operated ?
AC
page 2.20.2
With the isolation valve switch in AUTO, both engine bleed air switches ON, and both air conditioning pack switches AUTO or HIGH, what happens to the ISOLATION VALVE ?
it will close automatically
page 2.20.2
With the isolation valve switch in AUTO, both engine bleed air switches OFF, and both air conditioning pack switches OFF, what happens to the ISOLATION VALVE ?
it will open automatically
page 2.20.2
what is the aim of the external air cart ?
to provide an alternate air source for engine start or air conditioning
page 2.20.2
what is the aim of the APU bleed air valve ?
to permit APU bleed air to flow to the bleed air duct
page 2.20.2
what happens the to APU Bleed Air Valve when the APU is shut down ?
it will close automatically
page 2.20.2
how is the APU Bleed Air Valve controlled and operated ?
- DC controlled
- Pressure operated
page 2.20.2
what could possibly happen with both the APU and engine bleed air valves open, and the engines operating at idle thrust ?
there is a possibility of APU bleed air backpressuring the 9th stage shut off valve
page 2.20.2
when both the APU and the engine bleed air valve are open there is a possibility of APU bleed air backpressuring the 9th stage shut off valve, if this happens what would the 9th stage valve do ?
it will close
page 2.20.2
how does the air conditioning system provide tempered air and via what ?
by processing bleed air from:
- the engines,
- APU, or
- a ground air source
all via air conditioning packs
page 2.30.1
where does the air from the LEFT PACK flows directly to ? does it go through the mix manifold ?
flight deck it doesn’t go through the mix manifold
page 2.30.1
what type of air is combined in the mix manifold ?
- excess air from the left pack, - air from the right pack, - air from the recirculation system page 2.30.1
where is the combined air in the mix manifold distributed via what and where to ?
to the passengers cabin via the left and right side wall
page 2.30.1
what system or device can provide conditioned air ?
- airplane air conditioning system, or
- a preconditioned ground source
page 2.30.1
how does the conditioned air provided by the preconditioned ground source enters the air conditioning system ?
through the mix manifold
page 2.30.1
what controls the flow of bleed air that comes from the bleed air duct through the air conditioning PACK ?
pack valve
page 2.30.1
where does left and right pack bleed air usually come from ?
left engine n1
right engine n2
page 2.30.1
is a single pack capable of maintaining pressurisation and acceptable temperatures throughout the airplane ? and if so in HIGH or LOW flow ?
YES but has to be in HIGH FLOW
page 2.30.1
up to what altitude is a single pack in HIGH FLOW capable of maintaining pressurisation and acceptable temperatures throughout the airplane ?
up to maximum certified ceiling
page 2.30.1
How many PACKS is the APU capable of supplying bleed air for on the ground ?
two
page 2.30.1
How many PACKS is the APU capable of supplying bleed air for in flight ?
only one
page 2.30.1
how many PACKS are air carts capable of supplying adequate bleed air to ?
two
page 2.30.1
what type of air flow strength do the both PACKS in AUTO mode can provide ?
LOW FLOW
page 2.30.1
what happens if when in AUTO mode one of the PACKS stops operating ?
the other will go from LOW FLOW (both running) to HIGH FLOW (only one running)
page 2.30.1
when is the automatic switch from LOW FLOW to HIGH FLOW, after one of the PACKS in AUTO mode has stopped working, (is) inhibited ? and why ?
- when on the ground,
or
- in flight with flap extended to insure adequate engine power for single engine operation
page 2.30.1
what happens if both engine bleed air switches are OFF and the APU bleed air switch is ON ?
Automatic switching to “high air flow” regardless of flap position, air/ground status or number of packs operating
page 2.30.1
if you set the PACK on HIGH on the ground can this increase the air flow of the APU bleed air ?
yes it can to to HIGH
page 2.30.1
what is the aim of the Ram Air System ?
to provide cooling air for the heat exchangers
page 2.30.2
what is the Ram Air System automatically controlled by ?
by the PACKS through operation of ram air inlet doors
page 2.30.2
what is the position of the ram air inlet on the ground or during slow flight with flaps not fully retracted ?
full open position
page 2.30.2
do you have an indication in the plane of the ram air doors being fully opened ?
yes a RAM DOOR FULL OPEN blue light
page 2.30.2
what is the position of the ram air doors during normal cruise ?
fluctuates between opened and closed
page 2.30.2
explain the Cooling Cycle ?
The flow through the cooling cycle starts with bleed air passing through a heat exchanger for cooling. The air then flows to an air cycle machine for refrigeration and to a water separator which removes moisture. The processed cold air is then combined with hot air. The conditioned air flows into the mix manifold and distribution system.
page 2.30.2
what is the aim of the two AIR MIX VALVES (one hot, one cold) for each PACK ?
control hot and cold air according to the setting of the CONT CABIN or PASS CABIN temperature selector
page 2.30.2
where does the air that goes through the Cold Air Mix Valve goes to ?
Air that flows through the cold air mix valve is processed through a cooling cycle and then combined with hot air flowing from the hot air mix valve in the mixing chamber
page 2.30.2
where does the air that goes through the Hot Air Mix Valve goes to ?
through the hot air duct and then mixes with the cold air in the mixing chamber
page 2.30.2
when in automatic temperature mode what inputs does the automatic temperature controller uses ?
inputs from the respective respective temperature selector and cabin temperature sensor
page 2.30.2
describe briefly the air supply distribution system in the flight deck ?
Conditioned air for the flight deck branches into several risers which end at the floor, ceiling, and foot level outlets. Air diffusers on the floor under each seat deliver continuous air flow as long as the manifold is pressurised. the excess air from the flight deck is routed to the passengers cabin
page 2.30.4
describe briefly the air supply distribution system in the passenger cabin ?
The passenger cabin air supply distribution system consists of the mix manifold, sidewall risers, and an overhead distribution duct. Sidewall risers go up the right and left wall of the passenger cabin to supply air to the overhead distribution duct. The overhead distribution duct routes conditioned air to the passenger cabin. It extends from the forward to the aft end of the ceiling along the airplane centerline and also supplies the sidewall diffusers
page 2.30.4
what is the aim of the Recirculation Fan System ?
reduces the air conditioning system pack load and the engine bleed air demand
page 2.30.4
how does the Recirculation Fan System works ?
Air from the passenger cabin and electrical equipment bay is drawn to the forward cargo bay where it is filtered and recirculated to the mix manifold
page 2.30.4
is the motor that drives the fan AC or DC driven ?
AC
page 2.30.4
what stops the recirculating fan from working on AUTO ?
if both PACKS are on and one or both in HIGH
page 2.30.4
what is the aim of the Equipment Cooling System ?
cools electronic equipment in the flight deck and the E & E bay
page 2.30.4
what are the components of the Equipment Cooling System ?
a Supply Duct and an Exhaust Duct
each duct has a Normal and an Alternate fan
page 2.30.4
what is the role of the Supply Duct ?
supplies cool air to the flight deck displays and electronic equipment in the E & E bay
page 2.30.4
what is the role of the Exhaust Duct ?
The exhaust duct collects and discards warm air from the:
- flight deck displays,
- the overhead and aft electronic panels,
- circuit breaker panels in the flight deck,
- electronic equipment in the E & E bay
page 2.30.4
is the loss of airflow due to a failure in the Equipment Cooling System indicated by a light ?
YES, an OFF amber light
page 2.30.5
what will restore the loss of airflow due to a failure in the Equipment Cooling System ? how long will it take ?
Alternate Fan in approximately 5 seconds will restore air flow and extinguish the OFF light
page 2.30.5
why is the exhaust air from the equipment cooling system also diffused to the lining of the forward cargo compartment when the overboard exhaust valve is closed ?
for additional inflight heating
page 2.30.5
what controls the cabin pressurisation ?
the cabin pressure control system
page 2.40.1
how many controllers does the Cabin Pressurisation System have ?
two identical automatic controllers: AUTO and ALTN
one manual: MAN
page 2.40.1
what system supplies the bleed air to the Cabin Pressurisation System ?
the Air Conditioning System
page 2.40.1
how are pressurisation and ventilation controlled in the Cabin Pressurisation System ?
by modulating the Outflow Valve and the
Overboard Exhaust Valve
page 2.40.1
how many pressure relief valves does the Cabin Pressurisation System have ?
two
page 2.40.1
what is the aim of the pressure relief valves of the Cabin Pressurisation System ?
provide safety pressure relief by limiting the differential pressure to a maximum of 9.1 psi
page 2.40.1
what is the maximum differential pressure ?
9.1 psi
page 2.40.1
what is the role of the Negative Pressure Relief Valve ?
prevents external atmospheric pressure from exceeding internal cabin pressure
page 2.40.1
up to what altitude is the cabin altitude rate-controlled to ?
8000ft at the max certified ceiling of 41000ft
page 2.40.1
what type of motor driven controller does the Cabin Pressurisation System have ? AC or DC ?
DC
page 2.40.1
what is an ADIRU ?
Air Data Inertial Reference Unit
page 2.40.1
what is the aim of the ADIRUs ?
provides:
- ambient static pressure,
- baro corrected altitude,
- non corrected altitude,
- calibrated airspeed
to both automatic controllers
page 2.40.1
where do the ADIRUs receive barometric correction from ?
CPT or FO BARO reference selectors
page 2.40.1
what is a particular difference between the automatic controllers and the manual one regarding extra data provided with ?
The automatic controllers also receive throttle position from both stall management computers and signals from the air/ground sensors
page 2.40.1
mainly the cabin air outflow goes through the Outflow Valve and the Exhaust Valve, which other places is a bit of air also exhaust through ?
toilet and galley vents, miscellaneous fixed vents, and by seal leakage
page 2.40.2
does the majority of the overboard exhaust air circulate through the Outflow Valve or the Exhaust Valve ?
Outflow Valve
page 2.40.3
where does the passenger cabin air flow through before being exhausted overboard ?
through foot level grills, down around the aft cargo compartment, where it provides heating and then goes overboard via the outflow valve
page 2.40.3
when is the Overboard Exhaust Valve mainly used ?
On the ground and in flight with low differential pressure, the overboard exhaust valve is open and warm air from the E & E bay is discharged overboard
(In flight, at higher cabin differential pressures, the overboard exhaust valve is normally closed and exhaust air is diffused to the lining of the forward cargo compartment )
page 2.40.3
even if during the flight the Overboard Exhaust Valve is usually closed what situation could drive the valve open ?
if either PACK switch is in HIGH and the RECIRCULATION FAN is OFF
This allows for increased ventilation in the smoke removal configuration
page 2.40.3
what is the aim of the air/ground safety sensor ?
to signal whether the airplane is on the ground or in the air
page 2.40.3
when does the safety sensor drive the outflow valve fully opened to depressurise the cabin ?
on the ground and at lower power settings
page 2.40.4
what type of power settings on the ground will activate the outflow valve to start pressurising the cabin ?
high power settings
page 2.40.4
what type of rate is the cabin altitude change held to ?
minimum rate required
page 2.40.4
in case of a OFF SCHED DESCENT light illuminates what shouldn’t a pilot do in regard to FLT ALT indicator settings ?
If the FLT ALT indicator is changed, the automatic abort capability to the original takeoff field elevation is lost
page 2.40.4
to within what psi range is the cruise mode activated in the cabin pressurisation system ?
0.25psi below the cruise level
page 2.40.4
what would happen if the selected LAND ALT exceeds the target cabin altitude determined by the differential pressure limits ?
the controller will maintain a cabin altitude slightly below the selected LAND ALT
page 2.40.4
what is the Differential Pressure Limit at or below 28000ft ?
7.45 psi d
page 2.40.5
what is the Differential Pressure Limit
between 28000ft and 37000ft ?
7.80 psi d
page 2.40.5
what is the Differential Pressure Limit
above 37000ft ?
8.35 psi d
page 2.40.5
to within what psi range is the descent mode activated in the cabin pressurisation system ?
0.25psi below the FLT ALT
page 2.40.5
is the cabin programmed to be slightly pressurised at the landing ? why?
YES, so that rapid changes in altitude during approach result in minimum cabin pressure changes.
page 2.40.5
how soon does the controller drive the outflow valve open after landing ?
while taxing
page 2.40.5
which conditions would occur for the amber
AUTO FAIL light to illuminate ?
- Loss of DC power
- Controller fault
- Outflow valve control fault
- Excessive differential pressure (> 8.75 psi)*
- Excessive rate of cabin pressure change (±2000 sea level feet/minute)*
- High cabin altitude (above 15,800 feet).*
page 2.40.5
how to extinguish the AUTO FAIL Light ?
Moving the pressurisation mode selector to the ATLN position the ALTN light remains illuminated to indicate single channel operation
page 2.40.5
does the MANUAL mode operation of the Outflow Valve drive at the same rate of the automatic system ? what is the rate ?
slower rate
full range of motion takes up to 20 sec
page 2.40.5
