Air Management System Flashcards
What does the AMS use bleed air for?
- ECS (heating and cooling)
- Engine start
- Pressurization
- Engine and wing anti-ice
- Water pressure
- Hot air leak detection
The pressurization system consists of:
- Cabin outflow valve
- Statis pressure port
- Negative pressure relief valve
- Positive pressure relief valve
- Cabin pressure controller
Max differential pressure is:
8.7 PSI
When will the positive pressure relief valve open?
8.7psi
When will the negative pressure relief valve open?
-0.5psi
Max differential negative pressure is?
-0.5psi
How many AMS controllers are installed?
One controller with 2 channels which control the respective onside system
What happens if a channel fails>
The remaining channel is able to control the entire AMS
What provides air for the AMS?
- Engine bleeds
- APU bleed
- External pneumatic source
What is bleed air used for?
- ECS (heating and cooling)
- Engine start
- Engine and wing anti-ice
- Water pressure
In addition to air conditioning, what other functions does the ECS provide?
- Filtered cabin air recirculation
- Gaspers
- Fan air cooling for avionics
- Emergency ram air ventilation for clearing smoke from cockpit
How would an APU or engine bleed button show a detected leak?
An amber light illuminates on the button
What is external pneumatic air used for?
- ECS on the ground
- Engine start on the ground
The outflow valve can be modulated ___ or ___ .
Aeronautically, manually
Is manual pressure displayed on the MFD?
Yes, in psi.
When will the ground cart connection be displayed on the MFD?
Only when the ground cart is actually connected
The negative pressure relief valve opens when
If cabin pressure drops below outside pressure
The positive pressure relief valve (safety valve) is ___ driven
Pneumatically
When can the flight attendant control the temp in the passenger cabin?
Only when the pilot places the PAX CABIN TEMP knob to the ATTND position
How does the flight attendant know if the temp setting know allows her to adjust the temp?
An ENABLED led turns on whenever the pilot selects the ATTND in the cockpit
What does the ATTND position do on the PAX CABIN knob?
Switches over the cabin temperature control to the flight attendant control panel
What colors are used for set and actual temp in the cockpit and cabin on the ECS Synoptic page?
- CYAN is set
- GREEN is actual
Where is the external ground source panel located?
Lower fairing between the wings
What is the primary use for APU bleed air?
- ECS on the ground
- Engine starting on the ground
- Electrical source (
What happens when the BLEED 1 (2) pushbutton is out?
Allows automatic operation of the bleed valve by the AMS controller
What happens when the BLEED 1 (2) pushbutton is out?
Manually closes the engine bleed valve
What would be an indication of a detected engine bleed leak?
An AMBER light illuminating in the respective BLEED button
Are there lights in the BLEED buttons?
- Yes
- White stripe: closes the bleed valve
- Amber stripe - illuminates when a leak is detected
How many bleed regulating valves are in each engine?
2, one high stage (HSV) and one engine bleed valve (EBV)
Where is bleed air tapped from the engines?
- 6th and 10th stage compressors (EBV and HSV respectively)
What is the normal engine bleed pressure?
45psi
What is the purpose of the pre-cooler?
Cools the bleed air coming from the engine to the AMS
What cools the pre-cooler?
- Ground: N1 fan
- Flight: N1 fan or ram air
What protects the bleed system from an overheat condition?
The overheat detection system
What does the Overhear Detection System (ODS) observe?
- Engine bleeds, packs and air conditioning ducts
- APU bleed
- Plumbing for the wing an engine anti-icing system
How many loops does the ODS use?
2 loops within 6 sensor locations
Do both loops have to function in order to detect an overheat condition?
Yes, but if one fails the other will work along to detect the overheat
How many ECS packs are on the airplane? What provides air for the pack?
- 2, L and R
- Each engine provides bleed air to its respective pack
Can a single pack provide adequate temp control and pressurization?
Yes, up to FL 310
What happens when the PACK 1 (2) pushbutton switch is in?
Allows automatic operation of the pack valve by the AMS controller
What happens when the PACK 1 (2) pushbutton switch is out?
Manually closes the respective PACK valve
What happens when the APU BLEED pushbutton is in?
Allows automatic operation of the APU bleed valve by the AMS controller
What does pushing out the APU BLEED button do?
Closes the APU BLEED valve
Can a single engine bleed source provide adequate bleed to operate both packs?
Yes, through the cross-bleed valve
Wat is the ratio of fresh air to recirculated air?
52% fresh to 48% recirculated air
When are the recirculation fans commanded off?
- Cockpit switch
- smoke detected in the recirc bay
-DUMP button is pressed - Both packs are commanded OFF
Cargo bay fire signal activates - Fire test (shuts fans off momentarily)
- On ground cabin warm-up mode when the APU is the bleed source
How many recirc fans recirculate air back into the cabin and flight deck?
2
What is affected by turning the RECIRC fans OFF at the gate?
Cooling air stops in the forward and center E-bays