Air System Flashcards
What is the wind speed at which entry and cargo doors should not be operated
40 kts at the door
At what wind speed should the doors be closed
65 kts
How many portable oxygen cylinders are installed in the aircraft 787-900
19
Fwd equipment COOLING switch off
both forward equipment cooling supply fans
flight deck supply fan and vent fan are commanded off
smoke/override valve and flight deck isolation valve are commanded open forward cargo heat becomes inoperative
OVRD illuminates
Fwd equipment cooling OVERRIDE MODE
off is selected manually, or
both forward equipment cooling supply fans fail, or the smoke/override mode is automatically selected by the smoke detection system
Turning the flight deck temperature control toward C or W sets the desired temperature between
18° C and 29° C. Mid position (12 o’clock) sets approximately 24° C
PACK Switches Off (AUTO not visible)
CAC’s are commanded off.
PACK SWITCHES OFF ( illuminated amber)
both associated CAC’s are not running:
• automatically during engine start, or
• automatically due to a pack or compressor outlet high temperature, or
• OFF is manually selected
TRIM AIR Switches ON
the trim air valve is commanded open.
TRIM AIR switches Off (ON not visible) –
the trim air valve is commanded closed, and • FAULT illuminates
Trim air FAULT illuminated (amber)
the trim air valve is failed closed, or • the trim air valve is commanded closed because of a zone supply duct overheat, or • the TRIM AIR switch is selected off
if either the upper or lower switches are placed in the off position then
An EICAS advisory message RECIRC FAN UPR and/or LWR OFF is displayed
Aft Equipment Cooling (EQUIP COOLING AFT) SwitchOff (AUTO not visible) –
• both aft equipment cooling supply fans and vent fan are commanded off • override valve is commanded open • aft cargo heat becomes inoperative • OVRD illuminates
Aft Equipment Cooling (EQUIP COOLING AFT) Switch–OVRD (illuminated amber)
– SMOKE/OVRD mode is operating because: • off is selected manually • both equipment cooling supply fans fail, or • smoke/override mode is automatically selected by the smoke detection system
Cabin Temperature (CABIN TEMP) Control
Turning the control toward C or W sets the passenger cabin master reference temperature between 18° C and 29° C.
Air Conditioning Reset (AIR COND RESET) Switch
Push – • resets any air conditioning faults and attempts to restart normal operation • resets any trim air valves held closed due to overheat, control failure, or valve failure • attempts to reset a failed recirculation fan • resets fault protection
Alternate Ventilation (VENTILATION) Switch ALTN AMBER
9V-OJA - 9V-OJF ALTN (illuminated amber) - the Forward and Aft Outflow Valves are automatically repositioned towards the ten and one o’clock positions respectively when airplane is below 13,000 ft altitude and not on ground. The Alternate Ventilation System (AVS) provides an alternate means of ventilating the cabin and flight deck in the event both packs are inoperative. The system uses both the FWD and AFT outflow valves. When the airplane is
un-pressurized, placing the alternate ventilation system switch in ALTN positions the FWD and AFT outflow valves toward the ten and one o’clock positions respectively, allowing fresh outside air to be drawn into the air distribution system.
SHOULDER heater is Available in-flight only true or false
True
When IS the FOOT HEATER AVAILABLE ?
Available on ground and in-flight when pack and recirculation fans are on.
Liquid quantity display PECS
Liquid Quantity Display
QTY – • displays the left and right system reservoir quantities as a percentage of the normal service level (1.00 is the normal service level) • LO (amber) – displayed when the reservoir requires servicing • RF (white) – displayed when reservoir servicing is recommended • OF (white) – displayed when the reservoir is over–full
Note: A single liquid cooling loop is displayed when only one forward external power source is connected and selected ON.
How many temperature zones are there on 787
The airplane is divided into seven temperature zones: the flight deck and six passenger cabin zones.
Note: Zones A and B contain sub-zones A1 and B1 that are not depicted on the air synoptic.
When does the CAC inlet door deflects
During normal ground operations and landing phases of flight, deflector doors deploy in front of the CAC inlets to prevent debris from entering the CACs. These deflector doors may retract on the ground when ambient air temperature is below 2°C or above 35°C.
How many CAC are needed for its associated PACK ?
single CAC provides sufficient air to operate its associated pack in all operating modes.
How many pack control modes are there
Packs are controlled by two identical pack control systems. If one system fails, pack control automatically switches to the other system.
Pack ground operations how does the ram fan works and when
Pack Ground Operation
Both air conditioning packs are normally selected to AUTO for ground operations. Each pack uses a ram fan to draw air through the ram air system for ground operation cooling when sufficient main A/C Bus power is available.
On ground how many CAC s operate when APU IS THE ONLY power source. Is there any exception ?
Normally, to maximize system efficiency, only one CAC on each side runs when using the APU as the power source. During cold weather operations both CACs are commanded on.
For normal engine starts what happens to the CAC and the associated PACK eicas ?
All CACs are commanded off during initial start sequence with corresponding PACK L and PACK R messages inhibited.
When does the packs restart after engine start, what if both engines are started together
Packs do not restart until at least two minutes after 1) the engine start sequence is initiated and
2) the engine is running.
If both engines are started together, and the two minute limit is met, packs restart immediately after the second engine is running.
A ground source of conditioned air may be used to supply conditioned air directly to the —————————–, eliminating the need for pack operation.
cabin distribution system
What happens If an overheat or other significant pack fault is detected
the pack shuts down automatically and the EICAS advisory message PACK (L, R) is displayed
How can PACK operation be restored after a fault
An attempt to restore pack operation may be made by pressing the AIR CONDITIONING RESET switch.
For an in-flight starter assisted engine start, what happens to the CAC
only one CAC runs to maintain pack operation and maximize power available for the engine cross start
During a go-around with one engine inoperative, when can the pack l+ r message show momentarily. Is there any crew action ?
if slat autogap is needed, both packs could temporarily load shed and the PACK L+R message may show momentarily. No crew action is required for the PACK L+R message in this condition
For certain internal malfunctions, pack control automatically uses ______________as a backup to normal mode. what is the EICAS advisory message and where else can it be displayed
standby cooling mode PACK MODE (L, R) is displayed, and STBY COOLING is displayed in amber on the AIR synoptic.
What happens If one pack is in standby cooling and the other pack is operating normally
the pack in standby cooling mode shuts down at lower altitudes and higher outside air temperatures when ambient conditions do not permit standby cooling. The pack restarts automatically when altitude and outside air temperatures are suitable for standby cooling
What happens in standby cooling mode to the flight deck and cabin temperature
In standby cooling mode, pack cooling capacity may be less than in normal mode and may result in warm flight deck or cabin temperatures at lower altitudes
The flight deck receives 100% conditioned outside air true or false
yes, The flight deck receives 100% conditioned outside air
when may the flight deck receive recirculates air ?
Some recirculated air is supplied
to the flight deck if one pack is off and its associated lower recirculation fan is on.
Outside air flow is reduced during failure conditions and electrical load shed
conditions to protect the electrical power distribution system and to ensure that
sufficient electrical power is available to other critical airplane systems. TRUE OR FALSE
TRUE
can cabin crew reduce the ventilation to zero if they put the number of occupants as zero on the CAP
reduction is limited to ensure that a minimum air flow is
always supplied to the cabin.
how is additional cooling provided by the lower recirculation ducts ?
the lower recirculation ducts contain liquid to air heat exchangers.
How is lower recirculation cooling provided
provided by the integrated cooling system (ICS) which is a common galley cooling system
what are the effects of turning the recirculation fans to off
it does not increase the amount of fresh air to the passenger cabin but it results in decreased airflow instead.
CAUTION: Recirculation fans must remain ON during hot weather operations unless a non-normal checklist directs to select them off.
OJA-OJF
if smoke is detected in the AFT E/E equipment compartment what happens to the lower recirculation fans ?
the lower recirculation fans are commanded off
when does the de-humidification system work ?
The system operates automatically when electrical power is available
how does the de-humidification system work ?
It uses two zonal dryers (forward & aft) to remove moist air from the crown area. Fans recirculate dry air back to the crown area while moist air is exhausted below the cabin floor.
Each trim air system supplies how may cabin zone ducts and flight deck zone duct ?
2 cabin zone ducts and one flight deck zone duct
The target temperatures of each passenger cabin temperature zone may be further
modified plus or minus ______________within the range of 18º to 29º C, using the _____________
6º C, cabin
management system.
what controls the pack outlet
temperature.
The temperature zone requiring the coolest temperature
what happens If the flight deck or cabin temperature selector setting is unavailable to the pack
temperature controller
the pack outlet temperature is regulated to achieve either
the last temperature set or an average cabin temperature of 24º C.
what happens If the left or right trim air system is off,
the cabin temperature controllers attempt to maintain all zones at the average target temperature. Flight deck temperature is maintained between 18º and 29º C.
The flight deck may become uncomfortably warm or cool. Setting the CABIN TEMP selector to a cooler or warmer master temperature may achieve a cooler or warmer flight deck temperature.
The aft cargo compartment is heated but the compartment temperature is
uncontrolled true or false
true
how is Ventilation
and heat are provided to the forward cargo
forward E/E cooling exhaust, in-line electric heaters and
a forward cargo exhaust fan
the fwd cargo heater operates
to maintain a target temperature of ___________
21º C.
how is Bulk cargo compartment ventilation and heat are provided
from cabin air passing through a supply fan and in-line electric heaters. In addition, there is some residual
heat from the aft E/E cooling exhaust entering from below the compartment floor
what happens When an automatic overheat shutdown occurs BULK CARGO
cargo heat to the related compartment cannot be restored in flight. The EICAS advisory message CARGO HEAT BULK notifies the flight crew when the switch is off or a shutdown occurs.
Aft cargo compartment ventilation and heat are provided from____________
aft E/E cooling exhaust entering from below the compartment floor. In addition, there is some residual heat due to air leakage through the insulated curtain from the bulk cargo compartment.
[] CABIN ALTITUDE EICAS is of what level and what is the aural
warning level and aural siren
How can speed excursions when flying near VMO/MMO during descent avoided due to winds and temperature changes ?
Pilot intervention via FLCH speed or manually flown pitch adjustments.
CABIN TEMP HOT, CABIN TEMP COLD are annunciated or un-annunciated checklist ?
Un- annunciated checklist
[] CABIN ALTITUDE AUTO is of what level and what is the aural
CAUTION level, aural Beeper
OUTFLOW VALVE
OPEN CLIMB
CLOSE DESCENT
When manually controlling the cabin altitude and climb rate what is the recommended FPM for CLIMB and DESCENT
500 FPM
for both climb and descent
Recommended cabin altitude in cruise up to FL230 is (QRH)
Landing field elevation
CABIN TEMPERATURE is an annunciated checklist true or false. What is the objective of the checklist
TRUE
Objective is to descend and configure to provide alternate ventilation before the cabin or flight deck temperature causes incapacitation.
When the flight deck or cabin temperature is too cold as directed by [] Cabin temperature eicas what does the checklist say about diversion and what happens to the bulk cargo hear
Checklist instructs to land at the nearest suitable airport.
Bulk Cargo heat is inoperative
Alternate ventilation switch takes how long to reconfigure both outflow valves to the optimal flow position ?
3 mins
With Cabin Temperature cold under most conditions cabin temperature should become warmer at what FL
above 22000 ft
Cabin temp HOT
plan to land at the nearest suitable airport, descent to 10000 or lowest safe altitude
what is the similarity and diffrences of Equipment cooling OVRD AFT and EQUIP CLG OVRD FWD
after 30 minutes of operation at low altitudes ad low cabin differential pressure, non critical equipments may fail. For FWD equip cooling overide forward cargo hear is inoperative
what if a dog is being carried in the bulk cargo and the cargo heat bulk becomes inoperative ?
..
If a checklist says plan to land withing 345 minutes after take off what is the best course of action
..
which failure is more critical Equip cooling FWD or AFT
FWD
Both HUDs are inoperative.
Note: After 345 minutes, critical electronic equipment may fail. After 30 minutes, non-critical electronic equipment and EFB displays may fail. transponder/TCAS) may function for as little as 15 minutes before failing. By using both L and R side components, a total of 30 minutes of operation is possible for each function. Select functions OFF when they are not needed for safe operation. Operate one side (L or R) at a time when needed. To operate only one side at a time, select L or R component power to ON using the SYS
PWR menu. Then select the same L or R side using the TRANSPONDER menu and WEATHER RADAR menu (page 2/2).
If the checklist advices to run the engine at idle for the rest of the flight what should be done ?
–
what happens if The center pitot probe heat is failed.
The standby air data is unreliable in icing conditions
what happens if the left or right pitot probe heat is failed.
The PFD and HUD air data are not affected by the failure of one or two pitot heats.
what happens if the left, center, and right pitot probe heat are failed.
The standby air data is unreliable in icing conditions.
ICE CRYSTAL ICING IS AN UN-ANNUNCIATED CHECKLIST
Ice crystal icing or TAT probe icing. Ice crystal icing conditions exist when in visible moisture and one or more of the following are present:
Amber or Red wx radar returns below the airplane
Appearance of liquid water on the windshield at a temperature too cold for rain (the sound is different from rain )
The A/t is unable to maintain the selected speed
TAT on EICAS stay near 0 c
ICE CRYSTAL ICING information
An erroneous TAT indication can occur as a result of
ice crystals blocking the sensor. The erroneous
indication can last from one minute to more than 20
minutes. TAT normally should increase
approximately 2 degrees Celsius per 1000 ft of
descent.
