ECS Flashcards
How many AMS controllers are installed?
One controller with two channels which control the respective on side system
What does the Air management system (AMS) use bleed air for?
ECS (heating and cooling) Engine start Pressurization Engine and wing anti-ice Water pressure Hot air leak detection
What happens if the 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
What is external pneumatic air used for?
ECS on the ground
Engine start on the ground
Where is the external ground source panel located?
Lower faring between the wings
What is the primary use for APU bleed air?
ECS on the ground
Engine starting on the ground
Electrical source (<15,000 ft MSL)
Can engine bleed air flow back to the APU?
No. A check valve prevents flow back
Where is bleed air tapped from the engines?
6th and 10th stage compressors (EBV and HSV respectively)
System alternates between valves to regulate an adequate and safe pressure
What is normal pressure for any engine operation?
45 psi
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 does the Overheat Detection System (ODS) Observe?
Engine bleeds and packs
APU bleed
Plumbing for the wing and engine anti-ice system
To both loops have to function in order to detect and overheat condition?
Yes, but if one fails the other will work alone to detect the overheat
How many ECS packs are on the airplane? What provides air for the packs?
Two independent packs (left and right)
Each engine provides bleed air to its respective pack
Can a single pack provide adequate temperature control and pressurization?
Yes, up to FL310
Can a single bleed source power both packs?
Yes, through the cross bleed valve
What is the ratio of fresh air to recirculated air?
52% fresh air to 48% recycled air
When are the recirculation fans commanded off?
Cockpit switch
Smoke detected in the recirculated bay
DUMP button is pressed
Respective pack is commanded off
What keeps the three avionic E-BAYs cool?
- FWD & CRT E-BAY Three fans pull air from cabin to bay
* AFT E-BAY Natural air-flow from cabin to bay
When is the Emergency Ram Air Ventilation Activated?
Both packs commanded or failed OFF below 25,000 feet (via left side with electronic control)
Ram air pressure greater than cabin pressure (via right side)
How many channels on the Cabin Pressure Control (CPC)?
2 channels, 1 active and 1 in standby mode
Where does the CPC get Landing Field Elevation (LFE)?
FMS or can be manually selected