Compartment Temp INOP light
Compartment Temp range
65°F (18°C) and 85°F (30°C)
Equipment Cooling SMOKE light
CABIN ALTITUDE light and EICAS
-extinguishes when cabin alt is below 8500 feet
ENGINE HIGH STAGE light (757)
• Engine bleed system pressure is excessive
• Engine high pressure bleed air valve is automatically locked closed
- can only be unlocked on the ground by MX
How many temp zones
3 temperature zones: the flight deck and two cabin zones
What determines Pack output temp when pack controller in STBY mode?
Position of pack selector:
How is air distributed through the cabin and flight deck?
How is temp controlled with loss of trim air system?
How are FWD equipment racks cooled?
Equipment OVHT light illuminates
Smoke detected in equipment cooling system
How is Aft equipment cooled?
Automatic Pressurizations modes
In AUTO 1 or AUTO 2:
- systems arms when doors closed and T/O thrust set
Takeoff Mode:
Climb Mode:
- Max diff pres 8.6 psi at 35,000’
Cruise Mode:
- entered when constant altitude for 1 min
Descent Mode
- when aircraft descents more than 1000’
Landing and Ground Test mode:
CABIN AUTO INOP
- Cabin Altitude selector in MAN
What causes outflow valves to automatically close?
What happens to the packs and cabin air distribution when Cargo Fire switch is set to DEPR
What is bleed air used for?
Sources of engine bleed air
Low Pressure (LP) compressor - used during high power settings
High Pressure (HP) compressor - used during descent and low power settings
L or R ENG HI STAGE EICAS message (757)
What altitude can APU bleed air be used up to?
17,000’
What happens to the APU Bleed Valve after engine start?
APU Bleed valve will automatically close depending on the relative position of the engine bleed valves and the isolation valve.
How many external ground pneumatic connections
Two - 1 on the left duct and 1 on the right duct (757)
- both on left duct (767)
BLEED ISLN VAL EICAS message
isolation valve position disagrees with the commanded position