Air Conditioning - Boeing 757/767 Flashcards
What does the Cabin Altitude AUTO INOP light indicate?
Both Auto 1 and 2 are inoperative or manual mode is selected
What does the Pack Reset switch do when pushed?
Resets and overheated pack if the pack has cooled to a temperature below the overheat level.
When a Pack Control selector is positioned to STBY N, what is the outlet temperature of the pack inflight?
A constant, moderate temperature (40* inflight)
What can cause a Pack Off light to illuminate?
Pack valve is closed.
What cabin temperature do the packs attempt to maintain if the Trium Air switch is selected OFF?
Maintain all compartments at an average temperature of 75* (24C)
What is the purpose of trim air?
Hot trim air from the bleed system is added to meet the zone temperature requirements.
What does the Trim Air OFF light indicate?
Trim Air Switch is OFF.
What can cause a Compartment Temperature INOP light to illuminate?
Zone air overheat or fault in the zone temperature controller.
What crew action illuminates the AUTO INOP light on the Cabin Altitude Controller?
Selecting MAN position on the cabin Altitude Control Panel.
What happens when an automatic control system fault or a pack outlet overheat is detected?
The pack continues to operate in an uncontrolled, degraded condition, requiring crew action.
What are the expected pressurization limits for climbs and descents with Auto Rate knob selected to the index mark?
Climb - 500 fpm Descent - 300 fpm
(757) Which condition automatically opens the overboard exhaust valve?
The recirculation fan fails.
What condition activates the ground call horn?
Insufficient equipment cooling airflow detected on the ground.
(757) One forward equipment cooling system supply fan operates at a time. What starts the alternate fan?
Selecting the alternate equipment cooling switch to ALTN.
(757) what occurs if ALTN is selected on the alternate equipment cooling switch?
Activates the alternate supply fan and opens the overboard exhaust valve if required.
(RR) With the high altitude landing switch on, what cabin altitude annunciates the cabin altitude light and EICAS message?
14,650 ft
(767). What condition annunciates the equipment cooling valve light?
Equipment cooling valves are not in the commanded position.
(767) What does the equipment cooling OVHT light indicate?
High temperature or low airflow in the equipment cooling system.
(767) What does the equipment cooling SMOKE light indicate?
Smoke in the equipment cooling system.
(767) Selecting the equipment cooling selector to OVRD results in what equipment cooling actions?
Open smoke override valve in positions equipment cooling system for reverse airflow.
What cabin altitude extinguish is the cabin altitude light and EICAS message?
Cabin altitude below 8500 feet
What does a pack off light in associated EICAS message indicate?
Respective pack valve closed
(RR) With the high altitude landing switch off, what cabin altitude annunciate the cabin altitude light and EICAS message?
10,000 ft
What could cause compartment temperature INOP lights to illuminate?
Trim air switch is off
During automatic temperature control, which temperature zone controls the output temperature of the air conditioning packs?
The zone requiring the coolest air
What altitude setting is selected on the landing altitude indicator during cockpit preparation?
Landing altitude in feet
What occurs if the cabin altitude mode selector is set to AUTO 1 and it fails?
Control is automatically switched to AUTO 2 controller
