Chapter 2 - Air Systems Flashcards
The overboard exhaust valve (OEV) allows for:
(1x)
increased ventilation in the smoke removal configuration.
What is the position of the isolation valve when the ISOLATION VALVE switch is in AUTO?
Open if either engine BLEED air or air conditioning PACK switch positioned OFF.
(Think isolated.. either bleed or pack)
When making a no engine bleed takeoff and an engine failure occurs, when will the bleed air switch be positioned to ON?
When reaching 1500 feet or until obstacle clearance high has been attained.
The maximum cabin differential pressure (relief valves) is:
9.1 psi.
The Cabin Pressurization panel MANUAL light is illuminated green indicates:
the pressurization system is now in the manual mode.
Manual control of the cabin altitude is used if both the AUTO and ALTN modes are inoperative
The bleed air duct pressure indicator:
Is AC operated.
(Bleed air duct BAD Ass C)
The blue RAM DOOR FULL OPEN light illuminates:
when the ram door is in the full open position.
The amber OFF SCHEDULE DESCENT light illuminates. What does this indicate?
The airplane has descended before reaching the planned cruise altitude set in the FLT ALT indicator.
The main source of conditioned air for the flight deck is:
excess air from the left pack that is upstream of the mix manifold.
(The captain is the most important, the captain sits on the left side…)
The amber DUAL BLEED light indicates:
a possible APU back pressure condition and thrust must be limited to idle.
(dual bleed, dual source - engines + APU)
What systems rely on the bleed air system for operation?
- air conditioning / pressurization,
- engine starting,
- wing and engine anti-ice,
- hydraulic reservoirs and
- water tank pressurization.
What happens when the WING BODY OVHT TEST switch is pressed?
Both of the amber WING BODY OVHT lights illuminate.
With the engine bleed air switch ON, how are the engine bleed air valves powered?
They are DC activated and pressure operated.
What causes the PACK light to illuminate?
- failure of both primary and standby pack controls.
- pack trip off
What causes the amber PACK TRIP OFF light to illuminate?
The temperature in the pack has exceeded limits.
What fault indications can be reset with the TRIP RESET switch?
- BLEED TRIP OFF
- PACK TRIP OFF
- DUCT OVERHEAT.
In the PACK TRIP OFF non-normal procedure, the crew selects a warmer temperature in order to:
Reduce the workload on the affected air conditioning pack.
The recirculation fan:
reduces air conditioning pack load and engine bleed air demand.
A DUCT OVERHEAT will cause:
The air mix valves to drive to full cold.
Illumination of the amber AUTO FAIL light indicates:
- Loss of DC power
- Controller fault
- Outflow valve control fault
- Excessive Differential Pressure
- Excessive rate of cabin pressure change
- High cabin altitude
The BLEED TRIP OFF light indicates:
excessive engine bleed air temperature or pressure. The respective engine bleed air valve closes automatically.
What fault indications can be reset with the TRIP RESET switch?
a. BLEED TRIP OFF.
b. PACK.
c. ZONE TEMP.
d. All of the answers are correct.
In the PACK non-normal procedure, the crew selects a warmer temperature in order to:
reduce the workload on the affected air conditioning pack
A ZONE TEMP amber light indicates on the Master Caution Recall:
failure of the flight deck primary or standby temperature control.
Illumination of the amber BLEED TRIP OFF Light indicates what valve has automatically closed?
Related engine bleed air valve
The pack ram air system provides:
Cooling airflow for the pack heat exchangers when the aircraft is inflight or on the ground.
The ram inlet doors are fully open when:
- On the ground
- Inflight with flaps extended
- Inflight when maximum cooling is necessary
Which indications are given for the ram doors when they are fully open?
RAM DOOR FULL OPEN annunciator on the overhead panel
The RAM DOOR FULL OPEN light extinguishes when:
The ram door begins to close
The deflector doors are controlled by:
The air/ground safety sensor
The position of the ram inlet door is determined by:
The compressor discharge temperature
What position would you expect the ram inlet doors to be during cruise?
Full close (a small opening remains to allow for some air to pass over the heat exchangers)
What provides cooling air for the heat exchangers when the aircraft is on the ground or in slow flight?
A fan mounted on the shaft of the air cycle machine which extends into the ram air duct.
The three temperatures for C, W and AUTO are:
18, 30 and 21 degrees Celsius
The trim air system is used to:
Control the temperature of air delivered from 2 packs to 3 zones. This is controlled by a master TRIM AIR switch.
The trim air modulating valves:
Provide the temperature control to each zone
With trim air ON:
- Trim air pressure regulator and shutoff valve is OPEN
- This allows hot bleed air to flow to the three modulating valves
- The trim air modulating valves provide the temperature control to the three zones
With trim air OFF:
- The L PACK provides air at the temperature selected by the flight deck
- The R PACK provides air at a temperature which is an average between the FWD and AFT cabin temp selectors.
The RIGHT trim air controller provides modulation for the:
FWD CAB & CONT CAB
The LEFT trim air controller provides modulation for the:
AFT CAB & backup for CONT CAB
What is the logic for zone temperature control during single pack operation with the Trim Air switch ON?
Same as two pack operations
What is the logic for zone temperature control during single pack operation with the Trim Air switch OFF?
The operating pack attempts to provide air temperature that satisfies the average temperature demands of all three zones
If the Temp Selector is selected OFF:
The ZONE TEMP light illuminates. Temperature is determined from the pack only.
When adjusting temperature, monitor:
The associated CONT, FWD or AFT duct temp gauge and make 5 degree increments.
The ZONE TEMP light will illuminate for either:
A temp selector moved to the OFF position or a duct temperature overheat
If there is a temperature controller selector failure, which indications will you receive?
None. Upon recall only - ZONE TEMP.
When there is a failure of the FWD or AFT temperature controller:
The forward and after temperature selections are averaged.
With a trim air failure:
The left pack drives the CONT CAB temp and the right pack drives the FWD and AFT CAB temps, whichever is colder.
When the passenger trim air fails:
The forward and aft zone temp demands averaged for control of the right pack
If all zone controls and primary pack controls fail:
The standby pack controls command the packs to produce temperatures which will satisfy the average temperature demand of the two cabin zones.
The PACK light illuminates for:
- A pack trip or
- For failure of both primary and standby pack controls
- Excessive pack temp
The TRIP RESET switch can reset:
- BLEED TRIP OFF
- PACK lights
- ZONE TEMP lights
The recirc fans reduce:
Pack load and engine bleed air demand
Which recirc fan cools the E&E bay?
Right
The left recirc fan draws air from the:
Air distribution compartment
The right recirc fan draws air from the:
Main cabin and E&E bay
When on the ground and both packs selected to HIGH:
The left recirc fan will shutdown
When on the ground and both packs selected to HIGH:
The left recirc fan will shutdown
When on the ground and both packs selected to HIGH:
Both recirc fans will shutdown and the OEV will open
When the right recirc fan is OFF and either pack switch is HIGH, electrical equipment cooling is maintained by:
Opening of the OEV
The electrical cooling supply fan is a:
push fan
The electrical cooling exhaust fan is a:
pull fan
If airflow is not adequate for either the supply or exhaust fans for equipment cooling:
The associated OFF, MASTER CAUTION and OVERHEAD annunciator lights illuminates
For normal operations in flight when the right recirc fan is ON and cabin differential pressure is high exhaust air is:
Routed around (not into) the forward cargo compartment. This keep the liner warm.
When the right recirc fan is OFF and cabin differential pressure is high exhaust air is:
Exhaust air is ducted overboard through the OEV.
For normal operations on the ground when cabin differential pressure is low exhaust air is:
Exhaust air is ducted overboard through the OEV.
A single pack in HIGH flow can maintain:
Normal temperatures up to the maximum operating altitude
Ground air can operate the left pack if:
The isolation valve is open.
With both packs operating from engine bleed air, the packs operate at:
Low flow
High flow is provided by the APU when either:
Engine bleed air switches are OFF (automatic) and on the ground when engine bleed is off and pack switches are in the HIGH position
The isolation valve opens automatically when:
Either bleed switch or pack switch is in OFF
Bleed air is cooled:
As it passes through the primary heat exchanger. (airflow is provided by the ram air system)
If 5th stage bleed air is insufficient:
the 9th stage modulating valve will open
The bleed air valve is ____ powered and ____ operated.
DC, pneumatically
The precooler uses:
Engine fan air which is then dumped overboard.
The 9th stage air has a higher ___ and ___.
temperature, pressure
A BLEED TRIP OFF occurs for either:
5th stage temperature overheat or 9th stage excessive pressure.
The APU bleed air must be closed during ground use of EAI because:
back pressure of the 9th stage valve is possible, potentially reducing cowl anti-ice.
The DUAL BLEED light can illuminate when the #1 engine is not running and supplying bleed air because:
The light only monitors the position of the switch not the bleed valve.
The DUAL BLEED light can illuminate when the #2 engine is not running and supplying bleed air because:
The light only monitors the position of the switch not the isolation valve.
The DUAL BLEED light monitors the position of:
The APU valve, the isolation valve and the engine bleed switches.
The APU needs to be running at over ___ in order to supply bleed air.
95% RPM
The APU bleed air may be turned on after a ____ delay.
1 minute
The four unpressurized areas as:
- radome
- nose gear well
- main gear well
- aft compartment
The purpose of the packs are to offer:
air conditioning, ventilation and pressurisation
In the even one pack is inoperative, cabin altitude can be maintained at or below _____ when the aircraft is at _____.
8,000’, maximum certified altitude
Pressurization and ventilation are controlled by:
modulating the outflow valve and the overboard exhaust valve.
VH-VBY, VH-VBZ
The overboard exhaust valve is driven open if:
either pack switch is in high and the recirculation fan is off. This allows for increased ventilation in the smoke removal configuration.
2-VYFG - VH-RQP, VH-VOK - VH-YWE
The overboard exhaust valve is driven open if:
either pack switch is in high and the right recirculation fan is off. This allows for increased ventilation in the smoke removal configuration.
