Bleed Air Flashcards
Air for the pneumatic system is normally bled from the ________ of the compressor
Intermediate pressure stage
What happens in flight if pneumatic bleed air pressure is insufficient even with the HP stage valve open?
Engines spool up automatically
When the APU supplies air to the pneumatic system, the crossbleed valve automatically ______ and the engine bleed valve automatically ________.
Opens, Close
Pneumatic system operation is controlled and monitored by
Two Bleed Monitoring Computers (BMC)
I BMC 1 fails, what leak detection is lost?
Engine 1 and APU
If BMC 2 fails, what leak detection is lost?
Engine 2
The cross bleed valve automatically closes any time ________ is detected, except during engine start
An air leak
When will the APU BLEED FAULT light illuminate?
APU bleed leak detected
What valve close with an APU leak signal?
APU bleed and cross bleed
What valve close when a wing bleed leak is detected in flight?
Bleed valve on related side and cross bleed valve
When will the ENG BLEED FAULT light illuminate?
Bleed Overheat
Wing or engine leak of associated side
Bleed valve not closed with APU bleed valve open
The air conditioning system temperature is regulated by
Two PACK controllers and one zone controller
If theAPU is supplying bleed air or one PACK fails,________ flow is delivered regardless of pack flow selector position
HIGH
What happens if cooling demand is not met due to low bleed pressure?
Engine idle is automatically increased
The PACK valves close when the ENG MODE SEL switch is placed to IGN/START on the ground prior to engine start. When will they reopen?
Thirty seconds after first engine start if second engine start has not been initiated.
After second engine start
Thirst seconds after ENG MODE SEL switch is placed in IGN/START if no engine start is initiated.
The PACK ram air inlet ________ during takeoff
Closes
Hot________ air from the pneumatic system is used to maintain desired zone temperature.
Trim
If the hot air pressure regulating vale fails closed, the trim air system is
Inoperative
The HOT AIR FAULT light illuminates amber when a duct ________ is detected
Overheat
What happens to cabin temperature if the law/galley extract fan fails?
Cabin temperature is fixed at 59F
How many PACK controllers are there?
Two
How many channels in each PACK controller
Two
Which of the following is true if the primary PACK controller channel fails?
Secondary channel takes over automatically
What occurs if both PACK channels fail?
PACK outlet temp goes to a set temperature range
If the primary zone controller channel fails,
The PACKs provide a fixed temperature airflow to cabin and flight deck.
If both zone controller channels fail,
The message PACK REG appears on the ECAM screen.
Selecting the RAM AIR switch ON, opens the ram air inlet valve provided the ______ switch is not selected ON
DITCHING
When will the avionics ventilation system be in the closed configuration while on the ground?
Cold skin temperatures
The Air Conditioning RAM AIR switch is selected to ON, the differential pressure is less than 1 psi. The ram air inlet opens and the outflow valve
Opens to approximately 50 percent if the cabin pressure MODE SEL switch is in AUTO
In the Abnormal Configuration, the avionics ventilation reverts to a ________ configuration with air supply from air conditioning
Closed
While pre-flighting with the APU shutdown, you hear a horn in the nose wheel well. This may indicate a
duct overheat in the avionics ventilation system
The outflow valve is powered by one of ______ DC motors.
Three
Automatic transfer of the pressurization controller occurs after______ or in case of failure of the ______ controller
Landing, operating
Before takeoff and after landing, the outflow valve should be ______ and the cabin ______
Open, depressurized
The automatic pressurization controller normally uses landing elevation QNH from the
FMGC
During descent, the cabin pressure is controlled so that
It reaches landing field pressure just prior to landing
In the event of a divert to an alternate airport, how is the new landing field elevation normally provided to the automatic pressurization controller?
The FMGC provides database field elevation when a new destination is selected.
In the event of failure of both automatic pressure controllers, a their motor provides
Manual operation of the outflow valve
In case of failure of the two automatic controllers, a third back-up DC motor is provided for manual operation of the ______ valve
Outflow
Illumination of the MODE SEL FAULT light indicates
A fault is detected in both automatic pressurization controllers.
The cabin pressurization safety valve protects against
Excessive cabin Differential pressure
With the MODE SEL in AUTO, and the landing elevation set with the LDG ELEV selector, the cabin altitude is
Still controlled automatically
Switching the MODE SEL to MAN allows you to
Adjust the outflow valve
How is the pressurization system controlled manually? Select the MODE SEL to MAN, then
Momentarily hold the MAN V/S CTL switch in UP or DN
When will selecting the DITCHING switch to ON, NOT close the outflow valve?
When pressurization system is in manual operation
With the X BLEED selector in AUTO, what causes the crossbleed valve to open or close?
The APU bleed valve. If the APU bleed valve is open, the crossbleed valve opens. If the APU bleed valve is closed, the crossbleed valve closes.
When you turn on the APU BLEED switch, what affect does that have on the engine bleed valves, assuming the ENG BLEED switches are in AUTO?
When the APU BLEED switch is on, signals are provided to the BMCs, which command the engine bleed valves to close.
What happens to the PACK FLOW when the APU bleed is turned on?
High flow is delivered regardless of PACK FLOW switch position.
When else would the packs go to HI FLOW?
Any time there is a single source of air or any time one pack fails.
What would cause the FAULT light on the HOT AIR switch illuminate?
A duct overheat or disagreement between the zone hot air pressure regulating valve position and the commanded position.
Can the cargo compartment temperature be controlled on a non-China Southern A319 aircraft?
NO…
How can you set the correct landing field elevation for the auto controllers if both FMGCs have failed or if the elevation is not in the FMGC database?
With the LDG ELEV AUTO switch and the CABIN PRESS panel. Move the switch out of the AUTO position and set it to the landing field elevation.
If you set the landing filed elevation with the LDG ELEV AUTO switch, how can you tell the exact setting you have selected?
Actual value is displayed on the ECAM CRUISE and PRESS pages.
How many motors are used to drive the outflow valve and what is their power source?
Three. Two for the auto controllers and one for manual control. All three are DC powered motors.
Do all the motors operate simultaneously?
NO… Only one at a time
If the automatic pressurization system becomes inoperative, describe how you would manually control the pressurization.
Push CABIN PRESS MODE SEL switch and select MAN operation. Use MAN V/S CTL switch to open or close the outflow valve. Switch is spring loaded to neutral, so it has to be held in position until the target vertical speed is reached. UP moves valve towards open position and raises cabin altitude. DOWN moves valve towards closed position and lowers cabin altitude.
What is the most likely reason you would push the DITCHING switch?
For deicing the aircraft on the ground. ON closes six valves. Outflow MODE SEL must be in AUTO.
Why do we use the DITCHING switch to prepare the aircraft for deicing?
It closes six exterior valves to prevent deicing fluid from entering the aircraft. Closes the emergency ram air inlet, avionics ventilation inlet and extract valves and the outflow valve.
