1 - Air systems Flashcards
An APU switch with only a flow bar showing indicates
It is armed for automatic operation
How is the APU bleed controlled and actuated?
Electrically controlled and electrically actuated
How are engine bleed valves controlled and actuated?
Electrically controlled and pneumatically actuated
When will engine bleed valves open?
When pressure is sufficient to cause airflow
What does an engine bleed switch with a flow bar off indicate?
The valve is armed or has a fault
How is an isolation valve controlled and operated?
Electrically controlled and operated
What does a duct leak light indicate?
A leak anywhere in the bleed system
What does a bleed light indicate?
Excessive bleed air temp. This causes the engine bleed valve to automatically close
What does a high stage light indicate?
Excessive pressure. This causes the HP valve to automatically close for the remainder of the flight
Why would the Compartment Temperature Inoperative (INOP) Lights Illuminate
fault in the zone temperature controller
Compartment Temperature Control is OFF
the trim air switch is OFF
Describe the AUTO position of the Compartment Temperature Controls
- automatic compartment temp control
- pack output temperature is determined by the cabin temperature controller.
What does the OFF position do concerning the Compartment Temperature Control?
closes the compartment trim air valve
* the compartment temperature INOP light illuminates
TRIM AIR Switch ON/OFF
What occurs in each position?
ON – the trim air valve is commanded
open.
Off – the trim air valve is commanded
closed.
PACK RESET Switches. Why use them?
Resets an overheated pack if the pack has cooled to a temperature below the overheat level.
Pack INOP Lights. Why illuminated?
the pack is overheated
* fault in the automatic control system
Pack Off Light, hvað þýðir það?
PACK VALVE Closed
PACK Control Selectors. Hvaða mode eru í boði?
STBY MODE
N (normal) – constant, moderate temp
C (cool) – full cold operation
W (warm) – full warm operation
Foot og shoulder heaters. Virka bara á high hvenær?
HIGH er bara í boði í flugi.
What will cause the Equipment Cooling SMOKE Light to illuminate?
Smoke is detected in the forward equipment cooling ducts.
Describe the Alternate (ALTN) Equipment Cooling Switch
activates the alternate supply fan
On the 757-200ER activates the
auxiliary fan, if the alternate supply fan fails.
The Equipment Cooling Overheat (OVHT) Light illuminates for 3 reasons.
insufficient airflow (on the ground)
the supply fan is inoperative
the alternate supply fan is inoperative
When you rotate the Cabin Altitude AUTO RATE Control, what is it doing?
You are setting a limit for cabin altitude rate of climb or descent during auto control.
What is the function of the DETENT position?
Establish an approximately 500 fpm climb and 300 fpm descent
What has happened when you see AUTO Inoperative (INOP) Light
Either:
AUTO 1 and AUTO 2 cabin altitude control functions are inoperative or,
MAN mode is selected
Ef þú setur Cabin Altitude mode selector á AUTO þá er _____ valve controlled automatically
outflow
Það kviknar á hvaða ljósi ef þú setur MANUAL á Cabin altitude mode selector?
AUTO INOP light illuminates
What is the takeoff and landing Cabin differential pressure limit/placard?
.125 PSI
Þú færð Cabin Altitude ljós, when cabin altitude exceeds ______ feet, extinguishes when cabin altitude
descends below ____ feet.
10,000, 8500
What is the function of the High Altitude Landing Switch?
Reprograms system logic to initiate AURAL and VISUAL alerts at 14,650’ instead of 10,000’
what is the purpose of the Bleed Air System Isolation Switch? To open or close the _____ VALVE.
ISOLATION
If you notice the ISOLATION VALVE light, what is occurring?
The isolation valve position disagrees with the commanded position.
The engine BLEED AIR switches open when?
They open when engine bleed air is available. Pneumatic actuated. Held þú verðir að hafa ákveðið mikinn þrýsting svo þetta opnist.
What are the 3 reasons the Engine Bleed Air OFF light illuminate?
The engine bleed air valve is closed:
* automatically due to a system fault
* the switch is OFF
* the engine is not running
Why would a DUCT LEAK Light occur? A ____ temperature ____ air leak is detected.
high, bleed
Why would a BLEED Light occur?
The engine bleed air temperature is excessive.
Why would a HI STAGE Light occur? Engine bleed system pressure is excessive or
the engine _____ pressure bleed air valve is automatically locked closed.
high
What would cause a APU Bleed Air VALVE Light to Illuminate (amber)
APU bleed air valve position disagrees with commanded position.
How many temperature zones in the 757
Three, Flight Deck and two Cabin zones.
What occurs when there is an internal pack overheat?
The pack valve closes and the pack is shut down automatically.
During an internal pack overheat what lights will you see?
The ____ ____ light illuminates.
EICAS advisory L or R PACK OFF
PACK TEMP indications.
PACK OFF
What happens when you shut off the LEFT RECIRC FAN? The overboard _____ valve will open. Maintenance action is then required
exhaust
Why turn off the RIGHT RECIRC FAN?
To provide a more rapid exchange of air.
Where does the Flight Deck get its air? From the RIGHT PACK/LEFT PACK only.
LEFT
Where does the Flight Deck get its air if the LEFT PACK has failed? The flight deck receives air from the ___ manifold.
mix manifold
How much does our Fuel Flow increase with a recirculation fan off?
.3%
How does the FORWARD E/E system get cool?
The left recirculation fan draws air through the forward E/E system and returns it
to the ____ manifold.
mix manifold
What happens if the TRIM AIR system is off? (fyrir hitastig)
The packs attempt to maintain all compartments at an average temperature.
How does the forward equipment cooling system work?
The system has a supply fan that
draws cooling air from the cabin and forces it through the equipment racks and
avionics
After the forward equipment is cooled, where does the air go?
The air is then exhausted into the air conditioning mix manifold by the
left recirculation fan.
What occurs while the forward equipment is cooled and there is a low differential pressure?
The overboard exhaust valve automatically opens and most of the air is exhausted overboard
What lights will you view if a supply fan fails?
Equipment cooling OVHT light illuminates
EICAS advisory EQPT OVHT displays
What should be done after the supply fan fails?
Pushing the ALTN EQUIP COOLING switch, (an alternate supply fan is activated)
The 757-200ER has what backup for cooling of the ESSENTIAL avionics and electrical equipment
If both supply fans are inoperative an auxiliary fan automatically operates to provide cooling for essential avionics and electrical equipment.
In the 757-200ER what is the backup power source?
The hydraulic driven generator.
What happens when smoke is detected in the equipment cooling system?
SMOKE light illuminates.
EICAS advisory FWD EQPT SMOKE displays when smoke is detected in the equipment cooling system.
What happens automatically when smoke is detected in the equipment cooling system? one or both recirculation fans turn ___, one or both AC packs switch to ___ flow, the overboard exhaust ____ opens
off, high, valve
How would you describe the cargo heat system?
Completely automatic.
What protects the fuselage from excessive pressure differential?
Positive pressure relief valves and negative pressure relief valves operate
independently from the pressurization control system to protect the fuselage
against excessive pressure differential.
When will the CABIN ALT and CABIN ALTITUDE lights illuminate while the HIGH ALTITUDE LDG switch is on?
If the cabin altitude climbs above 14,650 feet . The lights extinguish and the EICAS message blanks when the cabin altitude descends below 11,800 feet
The ____ switch automatically closes the outflow valve when the cabin altitude exceeds _____ feet. Some models are auto and manual mode. Some models are auto only.
aneroid, 11,000
APU air is available up to __________feet.
17,000 feet
When would the BLEED ISOLATION be open?
Engine start
Single bleed source operation
When would you see a L or R BLD DUCT LEAK?
A high temperature bleed air leak is detected
What is the cause of a BLEED light on a 757? How many resets allowed?
“Bleed” = over temperature
(1 reset allowed)
What is the cause of a High Stage light on a 757?
How many rests?
“High Stage” = over pressure
No reset
When airplane has been electrically powered for more than __ minutes on the ground, equipment cooling must be provided.
20 minutes
Recirculated air makes up to ___% of total air volume. Packs supply the rest
50
The equipment cooling OVHTlight illuminates and the EICAS advisory message EQPT OVHT displays if the _____ fan fails.
supply
For takeoff, the system supplies a small [negative/positive] pressurization to cause a smooth cabin altitude transition.
positive
Cruising pressure altitude; The landing altitude and the scheduled cabin altitude are compared and the [higher/lower] of these two is selected for the cruise cabin altitude.
higher
During descent, cabin altitude decreases to slightly [below/above] the selected landing altitude.
below
The isolation valve separates the bleed air ducts into isolated segments.
The isolation valve is normally closed except for..
engine start or single bleed source operation.
Pack High Flow; Air flow is increased by ___% from normal rate.
65
Hverju þarftu að slökkva á, áður en þú notar ground conditioned air?
Packs
Enroute to EKCH after a discussion about the pros and cons of the EFB, you feel that the air in the cockpit is heavy, some fresh air is needed…
A) Turn off the L Recirculation fan
B) Turn off both recirculation fans for maximum amount of fresh air
C) The cockpit does not receive air from the mix manifold, so recirculation fans do not affect the air quality.
C) The cockpit does not receive air from the mix manifold, so recirculation fans do not affect the air quality.
Leaving the aircraft in Dubai on a charter cargo flight (TF-FIH) for a minimum crew rest layover. The OAT is 40°C. You are securing the aircraft, external power is available…
A) Connect the external power, complete the secure checklist and go have a beer or coffee.
B) Do a electrical power down according to supplementary procedure to prevent the aircraft equipment from overheating.
B) Do a electrical power down according to supplementary procedure to prevent the aircraft equipment from overheating.
OAT below 38°C. What is the maximum temperature in the cockpit on the freighter aircraft, before more cooling is required?
A) 40°C
B) 49°C
C) 34°C
B) 49°C
Passenger Aircraft: At and above what Outside Air Temperature is cooling required?
A) 40°C
B) 49°C
C) 34°C
C) 34°C
Crew call horn is sounding, what could be the reason?
A) Equipment overheat
B) IRS’s reverting to DC power because external power was disconnected some time ago
C) Somebody has tried to open the aircraft
A) Equipment overheat
B) IRS’s reverting to DC power because external power was disconnected some time ago
Smoke is starting to enter the cockpit, you suspect some equipment overheat. What checklist should you ask for?
A) EQUIPMENT SMOKE
B) SMOKE, FIRE OR FUMES
C) SMOKE OR FUMES REMOVAL
B) SMOKE, FIRE OR FUMES
When is the checklist “SMOKE OR FUMES REMOVAL” applicable?
A) At the first indication of smoke
B) When directed by the checklist “SMOKE FIRE OR FUMES” (When the smoke or fumes becomes the greatest threat)
B) When directed by the checklist “SMOKE FIRE OR FUMES” (When the smoke or fumes becomes the greatest threat)
What are the conditions for the Equipment Cooling Overheat (OVHT) Light to illuminate?
A) insufficient airflow (on the ground)
B) the supply fan is inoperative
C) the alternate supply fan is inoperative. (if installed)
All correct
When do the passenger oxygen masks automatically deploy?
14.000ft
When does the CABIN ALT light extinguish after a decompression event?
When the aircraft descents below 8.500ft
The aircraft does not have high altitude landing switch. When does the outflow valve automatically close, with cabin altitude controller in AUTO mode?
A) 10.000ft
B) 14.000ft
C) 8.500ft
D) 11.000ft
D) 11.000ft
“CABIN ALT AUTO 1” is displayed on STATUS in flight…
A) Do the CABIN AUTO INOP checklist immediately
B) This is a status message, no action is needed. The system automatically switches over to the other controller
C) Go to MAN mode on the cabin altitude controller and set the desired pressurization level
B) This is a status message, no action is needed. The system automatically switches over to the other controller
The aircraft is MEL’d with R Pack inop. During climb L Bleed EICAS msg appears and consequently L PACK OFF…
A) Do the L BLEED OFF checklist and consequently L PACK OFF checklist
B) Stop the climb and ask for a immediate descent as the aircraft is not being pressurized by the air system. The applicable checklist is the PACK OFF checklist.
B) Stop the climb and ask for a immediate descent as the aircraft is not being pressurized by the air system. The applicable checklist is the PACK OFF checklist.
Ground crew is connecting ground conditioning air for your turnaround. What is required of you as flight crew?
A) Nothing, just enjoy the cool air
B) Turn off the air-conditioning packs
C) Turn off the bleed air switches
B) Turn off the air-conditioning packs
If either the Packs overheat or have a controller failure, what will be the applicable EICAS message?
A) PACK OFF
B) ENG BLEED OFF
C) PACK TEMP
C) PACK TEMP
If you have a pack fault (PACK TEMP on EICAS). Will the relevant pack shut off?
A) Yes, it is broken
B) Sometimes, if there is internal overheat then the pack will shut off, otherwise the pack will run in a degraded mode
C) No, the pack has great resilience
B) Sometimes, if there is internal overheat then the pack will shut off, otherwise the pack will run in a degraded mode
Hvað eru mörg temperature zones í vélunum?
Flight deck + 2 cabin zones, nema TF-FIX og TF-ISX eru með 3 cabin zones
Hvar finnur þú “cooling required” töfluna og hvað segir hún?
OM-B -> Limitations -> Air Systems.
Segir til um hvenær þú þarft cooling á kerfin on ground, þ.e. hvað má vera heitt úti
Hvernig eru reglurnar um equipment cooling fyrir venjulega vél (ekki cargo)?
Ef þú ert meira en 20 mín on ground;
0-33°C: Ekkert
34-40°C: 1x Opposites sides hurðir opnar eða 1x A/C pack
41-49°C: 1x A/C pack
More than 49°C: Two A/C packs
The flight deck receives 100% fresh conditioned air from the…. and is maintained at a slightly ____ pressure than the passenger cabin.
left pack only , higher
Recirculated air makes up to ___% of total air volume.
50
The right recirculation fan can be turned off for several minutes to provide what?
The left recirculation fan should not be turned off as this causes the overboard exhaust valve to open.
a more rapid exchange of air
Þær vélar sem eru með hydraulicly driven generator (ETOPS), eru með tvær supply fans eins og hinar ef það verður EQPT OVHT. En þær eru líka með hvað?
Auxilliary fan powered by the hydraulic driven generator.
Cargo compartment heating and ventilation is completely….
automatic.
Kæling; the __ Recirc fan drawing air from the cockpit and E/E to the mix manifold and the __ recirc fan drawing air from the cabin to the mix manifold
L, R
If necessary, the cabin climbs to the cruise cabin altitude at ____ the auto rate or descends to the cruise cabin altitude at the ___ rate.
one-half, auto
Í climbi þá færðu CABIN ALTITUDE warning. Þú lækkar cabin altitude, hvenær hverfur ljósið?
The lights extinguish and the EICAS message blanks when the cabin altitude descends below 8,500 feet.
hold the cabin altitude MANUAL control to CLIMB to move the outflow valve toward close/open and cause the cabin altitude to climb
open. Þú ert að biðja cabin altitude að hækka (lægri þrýstingur) og opnar því fyrir
hold the cabin altitude MANUAL control to DESCEND to move the outflow valve toward closed/open and cause the cabin altitude to descend.
closed. Þú ert að biðja cabina altitude að lækka (meiri þrýstingur) og lokar því fyrir outflow svo það þrýstist upp loftið.
Hvaða kerfi pressurizar hydraulic resorvoir?
bleed air
Kemur bleed air úr HP eða LP engine compressor?
Báðum, LP air is used during high power setting operations.
HP air is used during descent and other low power setting operations.
The engine bleed air valves are “___” when the engine bleed air switches are selected ON.
armed, The valves are pressure actuated and remain closed until engine bleed air pressure is sufficient to cause forward flow.
Hvað þarftu mikið duct pressure ef þú ert að starta engine með ground pneumatic start? __ PSI
30 PSI
With the pack selector in the AUTO position, pack output temperature is determined by the cabin temperature controller. Zone temperature is then satisfied by the zone temperature controllers using ____ air.
trim
Ef það er sett high pack flow, hvað eykst flowið mikið um pakkanna?
65%
Hot weather tip; f on ground in hot weather with packs set to cold, after a while their output may decrease due to freezing of moisture in the air clogging the system.
To get the pack back to normal output, try….
selecting a warm temperature on the cabin and flight deck temperature controllers, this usually can solve the problem.
Ef þú ert að nota ground source of conditioned air (no bleed air from APU og ground external air), TAT probes are not aspirated. Hvað þarftu þá að passa?
Delay seleting an assumed temperature until after bleed air is available, annars er ekki víst að FMC/TMSP accepti assumed temperature derate.
R ENG HI STAGE displays when engine bleed
air pressure is excessive and the high pressure bleed air valve automatically…
locks closed.
ENG BLEED VAL displays if …
the engine bleed air temperature is excessive.
With the pack selector in the _____
position, pack output temperature is
determined by the cabin temperature
controller. Zone temperature is then
satisfied by the zone temperature
controllers using ____ air.
AUTO, trim
Conditioned air from the packs flows into a mix manifold where it mixes with air from two _______ fans.
recirculation
The flight deck receives 100%
fresh conditioned air from the right/left
pack only and is maintained at a
slightly higher pressure than the
passenger cabin.
left
If equipment smoke is detected, what can be observed in flight deck?
- One or both recirculation fans turn off.
- One or both packs switch to high flow
- Overboard valve opens
At what altitude do we get an EICAS warning about CABIN ALTITUDE and when does it extinguish?
10,000
8500
Outflow valve automatically closes when cabin altitude exceeds…
11,000’
Maximum allowable cabin pressure differential for takeoff and landing is…
0.125psi. Líka talað um 236ft below airport pressure altitude.
Max cabin differential pressure í flugi er…
9,1 psi
The EICAS msg “PACK OFF” displays when…?
Pack internal temperature is excessive
During descent into Dubai you enter a cloud. You notice your SAT is indicating -44°C therefore….?
You turn on the Engine Anti Ice since it should be on in descent
The ______ recirculation fan should NOT be turned off as this causes the overboard exhaust valve to open.
left
What does the HYD RSVR PRESS advisory message indicate?
Reservoir air pressure is low
Hvað eru mörg ground pneumatic?
3.
2 vinstra megin og eitt hægra megin.
Úr hvaða compressor er bleed air tekið?
Við high power setting þá úr low pressure compressor, en við lág power settings þá er tekið úr high pressure compressor.
Engine bleed air is ____ actuated
pressure
Hvað þýðir ENG BLEED OFF?
Bleed air is off because of system fault.
Loft sem kemur úr packs er á hvaða hitastigi?
Lowest selected
Ef packs eru bilaðir, havða hitastig kemur úr þeim?
Moderate (24°C).
Hvaða backup hefur þú á supply fan?
Bæði second supply fan, og auxilliary fan.
Pressurization; Ef Index er valið þá; Ascending ___ fpm, Descending ____ fpm.
500, 300
Pressurization; Ef Index er valið þá; Ascending ___ fpm, Descending ____ fpm.
500, 300
Þú ert að fara í takeoff í sjóðandi hita, varst bara með ground source of conditioned air (no bleed air), hvað gerist þá fyrir TAT probes og hvaða afleiðingar hefur það á takeoff?
TAT probe temperatures verða mjög há og geta valdið því að þú getur ekki notað assumed temperature derate. Bíddu með að velja assumed temperature þangað til bleed air er í boði.
Þú getur fengið tvær týpur af “air” frá ground, hver eru þau?
Conditioned air (beint inn í mix manifold og færð því ekki bleed úr því).
Bleed air (notað til að knýja áfram kerfi)
If necessary, the cabin climbs to the cruise cabin altitude at ______ the auto rate, when…
one-half, landing on a high altitude airport
Describe the Alternate (ALTN) Equipment Cooling Switch
activates the alternate supply fan
On the 757-200ER activates the
auxiliary fan, if the alternate supply fan fails.
During an internal pack overheat what lights will you see?
The PACK OFF light illuminates.
EICAS advisory L or R PACK OFF
PACK TEMP indications.
How does the FORWARD E/E system get cool?
The left recirculation fan draws air through the forward E/E system and returns it
to the mix manifold.
What happens if the TRIM AIR system is off?
The packs attempt to maintain all compartments at an average temperature.
What protects the fuselage from excessive pressure differential?
Positive pressure relief valves and negative pressure relief valves operate
independently from the pressurization control system to protect the fuselage
against excessive pressure differential.
Describe the aneroid switch
Automatically closes the outflow valve when the cabin altitude exceeds 11,000 feet. Some models are auto and manual mode. Some models are auto only.
When would the BLEED ISOLATION be open?
Engine start
Single bleed source operation
Pressurization controllers (AUTO 1, AUTO 2, MANUAL), hvernig er þetta powered?
AUTO 1 and 2 are AC power. MANUAL is DC powered by the DC Stby Bus.
If pack controller fails, it will output….
last commanded temperature. Það er trim air shutdown sem veldur því að packs reyna að gefa þér moderate air (24°C).
What happens automatically when Cabin Alt is above 11,000 in the auto mode?
Outflow valve is moved full closed. (Goes back to normal below 8,500)
Ef Recirculation fan (ein) er inop, hvað gerir pack high flow system?
Pack high flow system controls the pack valve to open a second schedule and provide more airflow if the fan is inop.
Each cargo compartment has 2/4/5 fans that can draw air through the smoke detectors. Only one fan operates at a time. The second or standby fan starts when?
two fans, automatically on sensing a failure of the operating fan.
Mach speed trim system operates what?
stabilizer
