Air Systems Flashcards
Engine Bleed Air Switches ON commands…
1.Engine bleed air valve open for engine start
2. Engine bleed air valve, PRV, and High Pressure bleed valve open by system logic when bleed air pressure is available
Engine bleed air switches off commands…
1.Engine bleed air valve, PRV, and High Pressure bleed valve closed
2. PRV valve opens when nacelle anti ice is on unless PRV is closed by:
-Prior or present bleed air overheat
-start valve not closed
-HP bleed valve failed open
Engine bleed switches are ___ controlled but ___ operated
electrically controlled but pneumatically operated
Bleed air system fault lights illuminate amber when
- Bleed air overheat
- Bleed air overpressure
- HP bleed valve open when commanded closed
- PRV open when commanded closed
Bleed air isolation valve light will illuminate amber when
Isolation valve disagrees with switch position
Engine bleed air valve illuminate amber when
Engine bleed air valve is closed
APU bleed air switch air valve light illuminated amber when
APU bleed air isolation disagrees with switch position
How many packs are there
3
If any pack fails for any reason, the remaining packs will go to
High flow
FLT Deck fan switch on with no packs operating
recirculated cabin air supplied to flight deck
FLT Deck fan switch on with at least one pack operating
Increases flow of conditioned air to flight deck
-Fan is disabled in flight
Flight deck temperature selector temp range
65F or 18C to 85F or 29C
Flight deck temp selector in backup mode
- sets and average flight deck temo from 18C to 29C
- Cabin temp panel control of zone temps is inhibited and automatic control of main deck zone temp is inhibited
Flight deck temp selector in Auto
Provided automatic control of flight deck temp
Flight deck temp selector in MAN the ___ valve is controlled manually
flight deck trim air. C moves valve closed provided cooler air and W moves valve towards open
Zone reset switch illuminates amber when
- Temperature zone duct overheat or zone temp controller fault occurs
- Master trim air valve is failed closed
- Trim air switch off
- Master trim air valve closed and pack air continues to flow
Zone reset switch push in
- Reset zone temperature controller if fault no longer exists
- Reopens master trim air valve if duct overheat no longer exists
- Reopens forward or after lower lobe cargo trim air shut off valve if duct overheat no longer exists
What is trim air?
Trim air add specific amounts of bleed air to any zone so that the temperature of each zone may be independently warmed
Trim air switch on allows for
- The master trim air valve to be open and flight deck, upper deck, crew rest and main deck zone trim air valves operate automatically
- Automatic and manual selection of pack controller A or B enabled
Trim air Switch OFF
- Master trim air valve is closed
- Forces pack output temp in backup mode and packs produce an average temp between 18C and 29C
- Cabin temp panel control of Crew rest and upper deck zones inhibited
- Pack controller A is selected and both automatic and manual selection of controller B is inhibited unless pack controler A fails which automatic selection of controller B occurs
Main deck temp selectors in AUTO
- Provides automatic control of main beck conditioned air temps.
- sets temp from 40F (4C) to 85F (29C)
- In back up mode automatic control is inhibited
Main deck temp selectors in manual
Main deck trim air valve is controlled manually