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99 Cards in this Set

  • Front
  • Back
Is air conditioning system pack control, cabin air recirculation, fault protection and overheat protection operated automatically or manually?
Normally operated automatically.
Is there a backup mode available if automatic temperature controls fail?
Yes.
How many temperature control zones are in the aircraft?
Seven. Flight deck, upper deck, and five main cabin zones.
TRUE or FALSE. With the Trim Air switch ON, the zone requiring the coolest temperature determines the temperature provided by the packs.
True. High temperature trim air is added downstream of the packs to heat the remaining zones.
What is the purpose of the recirculation fans?
To augment cabin air ventilation, allowing packs to be operated at a reduced flow during the period of low conditioned air demand while at Cruise altitude.
What is the advantage of the recirculation fans?
By allowing the packs to operate at reduced flow, engine bleed air requirements are reduced, which decreases fuel consumption and saves money.
When a ground conditioned air source is available (dual connections, two large hoses), can it be used to directly supply the conditioned air ducts in the cabin?
Yes, it can be used to supply conditioned air directly to the air conditioning distribution system, eliminating the need for pack operation.
When a ground conditioned air source is used, should the packs be ON or OFF?
OFF, pack operation is NOT required during ground conditioned air operation.
Pack operation is controlled by how many pack controllers?
Two. Controller A or B. Each has three control channels, one channel for each pack.
What occurs if one of the three pack control channels in a pack controller fails?
Control of the respective pack is switched automatically to the secondary controller. The other packs remain under the original controller.
What is the function of the NORM position on the Pack Control selector?
The pack valve is electrically armed in the NORM position, and the system automatically selects pack controller A or B on alternate flights. The selected controller is the primary controller. The system automatically selects the secondary controller in the event of a primary controller failure.
What does selecting the pack controller A position provide?
Selects pack controller A as the primary controller. (The system will automatically select B for pack control if A fails, even with controller A selected).
What does selecting the pack controller B position provide?
Selects pack controller B as the primary controller. (The system will automatically select A for pack control if B fails, even with controller B selected).
When do the air conditioning packs operate?
When the Pack Control selector is placed to NORM, A, or B, the respective pack valve will open when sufficient bleed air pressure is available.
How is the air conditioning pack valve controlled and operated?
When the Pack Control selector is placed to NORM, A, or B, the pack valve is controlled electrically by the pack controller, but operated pneumatically, requiring bleed air pressure to open.
What will generate a PACK 1, 2, 3 EICAS Advisory message and System Fault light?
- pack overheat.-- pack operation fault.
What will generate a PACK 1, 2, 3 EICAS Advisory message only?
- A fault in the pack controller.-- Shutoff of all engine bleed air.-- Either/both cabin pressure relief valve(s) are activated and pack 2 shuts down (PACK2 message only).-- Pushing FWD/AFT Cargo Fire Extinguishing Armed switch turns off pack 3(PACK 3 message only).
If a pack shut-down occurs because of a pack overheat or controller fault and the overheat or controller fault no longer exists, will the pack automatically come back on line?
No, the pack must be reset by pushing the Pack Reset switch on the overhead panel.
What are the general locations of the recirculation fans?
There are two upper fans located above the main passenger compartment ceiling and two lower fans located below the main passenger cabin floor, all four at mid cabin.
How is air circulated by the recirculation fans?
The fans draw cabin air through filters and reintroduce the air into the conditioned air distribution system.
What occurs if a fan overheat is detected?
Electrical power is automatically removed from that fan.
For what conditions will system logic automatically reconfigure pack flow and recirculation fan operation to maintain proper ventilation?
- a fan is NOT operating because of overheat.- a fan has failed.- a Recirculation Fan switch is OFF.
How many flow settings are provided by each air conditioning pack valve?
Two settings, normal and high.
What does the normal flow setting of the air conditioning pack valve do for the system?
The normal setting minimizes bleed air demands on the engines while in cruise, increasing aircraft fuel efficiency.
What does the air conditioning pack high flow setting provide?
An increase in the rate of cabin air exchange by supplying more pack generated air to meet maximum conditioned air requirements.
During normal operation when are the air conditioning packs in high flow and what is the associated recirculation fan configuration?
All three packs are normally in high flow, with both of the upper recirculation fans operating, during all phases of flight (ground, climb, descent) except cruise.
During normal operation, when are the air conditioning packs in normal flow and what is the associated recirculation fan configuration?
During cruise, the packs automatically operate at normal flow to reduce bleed air demands, and all four recirculation fans operate to maintain proper ventilation.
During abnormal conditions, when will the air conditioning packs shift to high flow?
Pack outputs are increased automatically to high flow and/or recirculation fans activated automatically as required to compensate for other packs or fans which are deactivated or inoperative.
Is the High Flow switch positioned ON or OFF for normal operation?
OFF, allowing system logic control of the packs.
Can the air conditioning packs be manually set to high flow?
Yes, by pushing the High Flow switch ON.
When is the PACKS HI FLOW EICAS Memo message displayed?
Only when the HI FLOW switch is manually selected.
When is the pack HI flow annunciation present on the ECS synoptic?
Anytime the Packs are in high flow.
What automatically controls the flight deck and passenger cabin air temperature?
The Zone Temperature Controller.
What modes of temperature control are provided for the flight deck?
Auto and manual.
What modes of temperature control are available in AUTO for passenger temperature control?
Normal automatic (trim air available) and backup control (trim air unavailable).
How is the master temperature set and where is it displayed?
It is set by the pilot with the PASS TEMP selector from 65 to 85 degrees. It is a magenta colored display at the top of the ECS synoptic.
How are the target and actual zone temperatures displayed on the ECS synoptic?
There are two numbers inside each zone. The target is magenta and the actual is white.
How is the target temperature for each passenger zone calculated?
Target temperature for each passenger zone is a summation of the master temperature set by the flight crew, plus zone temperature inputs from the flight attendants, plus comfort corrections made automatically by the Zone Temperature Controller during flight.
How much can the flight deck-set master passenger temperature be varied at the cabin temperature control panel available to the flight attendants at door 2R?
Passenger zone temperatures can be varied plus or minus 10 degrees from the comfort corrected master temperature, within the range of 65 to 85 degrees F.
How does the Flight Deck Temperature selector operate in the MAN position?
In MAN the flight deck trim air valve open/close position is controlled manually by the pilot.
What conditions illuminate the TEMP ZONE EICAS Advisory message and the ZONE RST SYS FAULT light (back-up temperature control mode)?
- zone duct overheat-- zone temperature controller fault-- master trim air valve has failed closed-- Trim Air switch OFF.
What is commanded by the air conditioning system when the Trim Air switch is selected OFF?
The master trim air valve closes and the backup mode is entered. Pack output temperature is selected by the PASS TEMP selector, in the AUTO range, on the overhead panel. Output temperature for all three packs can be set between 65°F and 85°F.
In the case of a zone duct overheat, the master trim air valve closes automatically and the temperature controller will switch automatically into the backup mode. Will the system automatically reset itself?
No, zone temperature control may be reset to the normal automatic mode by pushing the ZONE RST switch, provided the zone duct overheat condition no longer exists and the Trim Air switch is ON.
Do the Captain and First Officer & apos;s foot and shoulder heaters operate on the ground?
No.
How is cabin altitude controlled?
By regulating the discharge of conditioned air through two outflow valves at the rear of the cabin.
Where is pressurization information displayed?
The ECS data block includes: cabin altitude, rate of change, landing altitude, control mode, and differential pressure. The ECS data block is displayed at the bottom of primary EICAS when the ECS synoptic or ENG display is selected on secondary EICAS or when an ECS non-normal condition occurs. Outflow valve position/control mode is displayed on the ECS synoptic and on the Overhead panel.
TRUE or FALSE. During takeoff, the outflow valves should automatically close when the thrust levers are advanced to takeoff thrust and cabin altitude should descend slightly below field elevation.
True. When the thrust levers reach takeoff range and the aircraft accelerates past 65 knots, the outflow valves enter the takeoff mode, and cabin altitude is set to slightly below the takeoff field elevation.
How is the pressurization system normally operated?
Automatically, by cabin altitude controller A or B.
In the AUTO mode what is the cabin rate of climb or descent based on?
A rate proportional to the aircraft rate of altitude change.
Can the pressurization system be operated manually?
Yes.
How many cabin altitude controllers are active at a time?
One.
If only one cabin altitude controller is active, what is the status of the inactive controller?
It is receiving information identical to that being utilized by the active controller and is standing by, ready to switch into active control should a fault in the other controller occur.
When is the active cabin altitude auto controller tested?
Continuously.
When is the inactive cabin altitude auto controller tested?
Automatically, upon landing.
Engine bleed valves are _________ controlled and ________ operated.
electrically; pneumatically.
TRUE or FALSE. A failure of the active auto controller does not require any immediate crew intervention.
True. The system automatically switches to the alternate auto controller.
TRUE or FALSE. The CAB ALT AUTO EICAS Caution message displays if either one of the automatic pressurization systems fail.
False. Only when both auto controllers fail, or when MAN mode is selected on both outflow valves.
How is landing field elevation entered into the cabin altitude controller?
Automatically by the FMCs, or manually using the LDG ALT selector on the overhead pressurization panel.
Does manual input of landing field elevation override FMC inputs?
Yes.
What is the relationship between cabin altitude set for landing by the cabin altitude controller and actual field elevation?
Cabin altitude for landing is set slightly below actual field elevation so the cabin is pressurized slightly for landing.
What is the range of altitude selection for landing cabin altitude?
1,000 feet below sea level to 14,000 feet above sea level.
When does the aircraft normally depressurize?
Landing cabin altitude is set slightly below destination field elevation so that the cabin is pressurized slightly on landing. At touchdown the outflow valves automatically open, depressurizing the cabin.
If one Outflow Valve Manual switch is ON while the remaining valve is controlled automatically, will both outflow valves operate?
Yes. The manually selected outflow valve must be controlled manually. The other outflow valve will continue to operate automatically.
What does an OUTFLOW VLV L or R EICAS Advisory message mean?
Automatic control of the outflow valve is inoperative or the Outflow Valve Manual switch is ON.
How is outflow valve position monitored?
Outflow Valve Position indicators are located on the Overhead panel and are also displayed on the ECS synoptic.
If both Outflow Valve Manual switches are pushed ON, can the cabin altitude controllers monitor outflow valve position?
No. If both Outflow Valve Manual switches are pushed ON, the cabin altitude controllers are bypassed completely.
When is the EICAS Warning message CABIN ALTITUDE displayed and the warning siren sounded?
If cabin altitude exceeds 10,000 feet.
How can the cabin altitude warning siren be silenced?
By pushing the Master Warning/Caution Reset switch or by cabin altitude descending below 9,500 feet.
When will the system automatically close the outflow valves regardless of what the cabin altitude controllers are commanding?
When the cabin altitude reaches 11,000 feet with the system in the automatic mode, the cabin altitude controllers are bypassed and the outflow valves are closed automatically.
When does the CABIN ALTITUDE EICAS Warning message and siren rearm?
When the cabin altitude descends below 9,500 feet.
How is excessive positive cabin pressure avoided?
Two mechanical positive pressure relief valves are installed on the side of the aircraft forward of the left wing to prevent overpressurization of the airplane.
What automatic protective feature acts to help relieve excessive pressure?
If an overpressurization is sensed, the pressure relief valves open and pack 2 shuts down automatically to assist in relieving excess cabin pressure. A PACK 2 EICAS Advisory message annunciates without a SYS FAULT light.
In the event of excessive cabin pressure, do both cabin pressure relief valves have to open to shutdown pack 2?
No, opening either pressure relief valve will shutdown pack 2 in an overpressure situation.
In the event of a shutdown of pack 2 due to overpressurization, how is the pack reset?
If normal cabin pressure is restored both cabin pressure relief valves are closed and pack 2 is automatically reset.
How is a negative pressure condition prevented on the aircraft?
Negative pressure relief valves installed in the forward and aft cargo doors, and both upper deck doors, open when outside pressure is greater than inside pressure.
On aircraft 6301- 6310 what is the function of the "pull-on" Landing Altitude selector on the Overhead panel?
The pull-on knob overrides any landing altitude inputs to the cabin altitude controllers from the FMC. When pulled ON, landing altitude must be set manually and is displayed on EICAS followed by an amber MAN. Aircraft 6311 and beyond have a separate pushbutton switch for selecting MAN mode.
Upon landing after an overpressurization event the __________ must be closed and reset by _____________.
overpressurization valve covers (blow out fairing doors); maintenance.
What does pushing the Landing Altitude selector to OFF provide?
Landing altitude is automatically input to the cabin altitude controllers from the FMC. Landing altitude information is displayed in the ECS block on Primary EICAS followed by a white AUTO.
Where is the warmed equipment cooling air exhausted after passing through the equipment racks?
Warm exhaust air is ducted automatically either overboard (on ground, temperature above 45 degrees F, or fewer than one engine running on each wing), or, into the forward cargo compartment (on ground, temperature below 45 degrees F, or at least one engine on each wing running, or inflight) .
How is the warm exhaust air routed with the Equipment Cooling selector positioned in STBY?
Commands the system to flight mode. The inboard exhaust valve is opened and the ground exhaust valve is closed, providing forward cargo heat regardless of ambient temperature.
How does the OVRD mode provide equipment cooling in flight?
With the Equipment Cooling selector in OVRD, the internal fans are deactivated and the smoke/override valve opens, with all other valves closed. The smoke/override valve opens to an overboard vent, allowing cabin differential pressure to create a reverse flow of air across the equipment, through the supply duct, then overboard.
How is the forward cargo compartment heated?
The forward cargo compartment is heated by warm equipment cooling system exhaust air. It is further augmented by two electric heaters which automatically operate only when warming air flows into the compartment.
Is there forward cargo heat if the equipment cooling inboard exhaust valve is closed?
No.
How are aft cargo heat and forward cargo heat connected?
They are not. Aft cargo heat is independent of the forward cargo heat system.
How is the aft cargo compartment heated?
With the Aft Cargo Heat switch ON, center bleed duct air flows into the aft cargo compartment through a temperature control valve and an overheat shutoff valve, which automatically regulate airflow to maintain compartment temperature within a preset range.
Where are live animals carried?
Only in the aft cargo bay, warming air may NOT be available to the forward cargo bay.
Where are the cargo bay temperatures displayed?
On the ECS synoptic below the main cabin temperatures.
How do the temperature control valve and overheat shutoff valve maintain proper temperature in the aft cargo compartment?
With the Aft Cargo Heat switch ON, the temperature control valve and the overheat shut-off valve are opened. Compartment temperature is regulated by a thermal switch, which opens and closes the temperature control valve. When the compartment is cool, the thermal switch sends a signal to open the temperature control valve, allowing warm center bleed duct air to flow into the compartment. When the compartment warms to the upper limit, the thermal switch signals the temp control valve closed to stop the flow of bleed air. As a backup, if the temperature control valve fails open and the aft cargo compartment temperature reaches the overheat range, the overheat shutoff valve closes automatically.
What condition will illuminate the TEMP light in the Aft Cargo Heat switch and display the EICAS Advisory message TEMP CARGO HEAT?
If the temperature control valve fails open, the temperature will rise to a preset overheat temperature threshold. As temperature continues to rise, the TEMP light will illuminate. When the temperature reaches a higher second threshold, the Overheat Shutoff valve will be automatically commanded to close. The TEMP light and EICAS Advisory message TEMP CARGO HEAT will be displayed and will cycle on and off as the temperature cycles between the second overheat temperature threshold and the original temperature control valve threshold.
What does selecting the Aft Cargo Heat switch to the OFF position accomplish?
Selecting the Aft Cargo Heat switch to OFF commands both the temperature control valve and the overheat shutoff valve to close.
Just after pushback with two engines running, the flight attendants indicate that the cabin is too warm. What can the flight crew do to help out?
Verify that the PASS TEMP selector switch is in the 12 o' clock position so the Flight Attendants have their full temperature control range (65 to 85 degrees F).
With the cabin pressurization system in the AUTO mode, the outflow valves automatically close when the cabin altitude exceeds _____________.
11,000 feet.
How does the air conditioning system satisfy the varying temperature requirements of the individual zones, when the system is operating normally?
Master Temperature and flight deck temperature are set on the flight deck. Individual zone temperatures are set at door 2R by flight attendants after two engines are running. The pack controller regulates the pack output temperature to satisfy the zone requiring the coolest temperature. All three packs output the same temperature. The zone temperature controller then modulates individual zone trim air valves to mix hot bleed air with conditioned air to achieve the respective target temperatures.
With the center pneumatic duct providing adequate air, automatic temperature control by the Zone Temperature Controller is available if the Trim Air switch is __________.
ON.
How should the RECIRC fan switches be set during preflight?
ON, allows automatic operation to maintain proper cabin ventilation.
What control is used to adjust the temperature of the flight deck?
The FLT DECK Temperature selector.
While parked at the gate with no engines running, the flight attendants indicate that the cabin is too warm. What can the flight crew do to help out?
Turn the PASS TEMP selector switch to full cold (C). Note: the flight attendant temperature control panel located at door 2R does NOT operate with less than two engines running.
How is an outflow valve manually opened or closed?
Select Left or Right Outflow Valve Manual switch ON, hold the Outflow Valve Control toggle switch OPEN or CLOSED.
How can pilots set the temperature in the Aft Cargo compartment?
Pilots cannot set the temperature.