7ER Air Systems Flashcards
(42 cards)
What is the function of the COMPT TEMP selectors?
AUTO - provides automatic temperature control within the indicated range
OFF - closes the associated trim air valve and illuminates the associated INOP light
What are the causes of an INOP light on the COMPT TEMP panel?
A fault in the associated zone temperature controller
The Compartment Temperature selector is OFF
The TRIM AIR switch is OFF
What is the function of the FLT DK temperature selector? (753)
AUTO - provides automatic temperature control with its range (65F - 85F)
OFF - closes the flight deck trim air valve, illuminates the associated INOP light
What is the meaning of the INOP light next to the FLT DK selector?
A fault in the zone temperature controller,
the FLT DK temperature selector is OFF, -OR- the TRIM AIR switch is OFF
What is the function of the MAN position on the FLT DK temp selector (767)?
Provides manual control of the flight deck trim air valve. When in MAN mode, the selector is spring-loaded to the 6 o’clock position.
What is the meaning of a L(R) ENG bleed OFF light?
The associated engine bleed valve is closed, due to:
A system fault, the switch being OFF, or the engine not being running
What are the indications of a dual auto pressurization controller failure?
AUTO INOP light on CABIN ALTITUDE CONTROL panel
What are the indications of a single pressurization controller failure?
There are none - the controller switches without the selector being moved
What is the meaning of an illuminated AUTO INOP light on the CABIN ALTITUDE CONTROL panel?
Both AUTO 1 and AUTO 2 functions are inoperative, or the selector is in MAN
What is the meaning of a Cargo Heat OVHT light?
The associated cargo compartment temperature is above the standard control range, or the shutoff valve has been signaled closed
What is the function of the trim air system?
Hot air is removed from the bleed lines upstream of the packs, and is blended back in later on to fine tune the zone temperatures. The packs attempt to output temperature to meet the requirements of the zone with the coldest setting.
If the trim air system fails, the packs attempt to maintain temperature at an average value.
What is the meaning of an illuminated OFF light in the Trim Air switch?
The switch is off.
[“TRIM AIR” EICAS adv]
What action must be taken on the Cabin Altitude Control panel in the event of a diversion?
The Ldg Alt window must be reset
Describe the function of the gasper system
Draws air from the forward overhead air conditioning ducts and distributes it to the passenger gaspers.
No flight deck controls on the 757, one switch on the 767 to control a gasper fan
Describe the purpose of the recirculation fans
Maintain cabin circulation while allowing a reduction in cabin ventilation, allowing the packs to operated at a reduced flow
Recirc fans can be turned off to improve ventilation, but the L fan on the 757 should never be turned off because of its equipment cooling function
How can the cabin altitude be manually controlled?
Move Mode Select selector to MAN, move Manual selector to either CLIMB or DESCEND
What is the function of the cabin altitude Auto Rate knob? What does the index mark indicate?
Functions only in AUTO 1 or AUTO 2 mode, and sets the limit for cabin climb and descent rate.
The index mark indicates about a 500fpm climb and 300fpm descent, and is the proper preflight position
What is the location and function of the Bulk Cargo Heat selector, and what is its preflight position?
On the P-61 accessory panel
NORM - standard heating range, VENT - higher range, and activates ventilating fan
Preflight position is VENT
What is the function of the Equip Cooling selector?
AUTO - control of the equipment cooling is automatic
STBY - positions the equipment cooling system for inboard air flow
OVRD - positions the equipment cooling system for reverse air flow, shuts down the Nitrogen Generation System (if installed) and arms the NO COOLING light
Only installed on 767
What is the meaning of an illuminated NO COOLING light?
No reverse airflow through the Equipment Cooling System
What is the meaning of an Equipment Cooling OVHT light (767)?
High temperature or low airflow in the equipment cooling system
What is the meaning of a PACK OFF light?
The pack valve is closed, and the pack is off
What is the meaning of a Pack INOP light?
A pack outlet overheat has been detected, or a control system fault has been detected
[“PACK TEMP” EICAS adv]
What are the functions of the Pack Control selectors?
OFF - closes pack valve
AUTO - automatic control of the pack
STBY - bypasses automatic control and sets the pack to predefined constant levels: N is normal, C is full cold, W is full warm
