Flashcards in Study Guide Air Management System Deck (31)
How many AMS controllers on plane?
One with two Channels.
What provides air for the AMS?
External pneumatic source
What is external pneumatic source used for?
Engine start and environmental control
Where is the external pneumatic ground source panel?
Lower fairing between the wings.
What is the primary use for APU bleed air?
ECS on the ground.
Engine starting on the ground.
Engine start in flight up to FL210
Ecs up to 15,000
Can engine bleed air flow back into APU?
No, q check valve prevents that from happening.
What compressor stages are used for bleed air?
Sixth and tenth.... The system alternates between valves to regulate an adequate and safe pressure.
Normal bleed pressure for any engine?
Purpose of the precooler?
Cools bleed air coming from the engine to the AMS.
What cools the precooler?
On the ground, N1 fan.
In flight the N1 fan or ram air?
What does the overheat detection system (ODS) observe?
Engine bleeds and packs.
Plumbing for eh engine and wing anti ice system.
Do both loops of ODS have to function to detect a bleed system overheat?
Yes, but if one fails the other will work alone.
Single pack limit?
Can a single bleed source power both packs?
Yes, through the cross bleed valve.
When are the recirculation fans commanded off?
Flight deck switch
Smoke det cited in recirculation bay.
DUMP valve pressed.
Respective pack is off.
What keeps the three e bays cool?
Front and center... Three fans in each bay pull air from the cabin.
Aft... Natural air flow from cabin to the bay.
When is the EMER ram air vent activated?
Below 25,000 and both packs failed or commanded off.
Ram air pressure is greater than cabin pressure on the right.
Where does the CPC... Cabin pressure controller.... get landing field elevation?
Fms or manually selected.
What happens when the dump button is pushed?
Commands both packs off
Opens the outflow valve open and raises the cabin to 12,400 at a rate of 2,000 feet per minute.
Can the cabin altitude be raised above 12,400?
Yes, by using manual mode.
Cabin will also rise due to a natural leak.
In manual mode will the cabin depressurize on landing?
What is the bleed system priority?
Inside engine... Opposite side engine... APU if available.
If engine and APU bleed air are available simultaneously, which has priority?
APU has priority if.... On the ground, wheel speed less that 50 knots and opposite engine bleed pressure is not enough for an engine start.
When will the cross bleed valve automatically open?
If only one side bleed source is available.
Engine two start in flight.
Engine one start in flight if the APU is not available.
What will close the ESS packs?
Any engine start if APU is the bleed source.
Engine start on ground.
Respective bleed duct system leak.
Bleed air source not available.
Thrust levers set to max on takeoff.
REF A/I set to ALL on takeoff.
REF ECS set to OFF in MCDU (APU is OFF)
When are the ECS packs recovered?
TL not at max and 500 feet agl with both engines operating or if at 9,700 feet MSL with one engine operating.
What happens if smoke is detected in the recirculation bay?
Both recirculation fans deactivate.
Cargo recirculation fan deactivates
Cargo outflow valve closes.
Where does the CPCS get cruise flight level and landing elevation from?
FMS before takeoff or CPCS calculates using ambient pressure.
LFE can be manually inputted.
What color is the LFE on the EICAS?
Green if done by FMS
Cyan if manually done and will have an M in front of the number.