ATA 21

AEVC WILL CHANGE THE SYSTEM CONFIGURATION DEPENDINGON:

• Aircraft skin temperature.

• Whether the aircraft is on ground or in flight.

• Whether the aircraft is on ground or in flight and aircraft skintemperature.

DURING TAKE-OFF AND LANDING, THE RAM AIR INLET FLAP IS:

• Fully open to increase air flow into heat exchangers.

• Fully closed to prevent ingestion of foreign objects.

• Modulated to close.

FUNCTION OF THE MIXER UNIT:

• Mixes air from packs and re-circulated air from the cabin.

• Mixes air from packs and bleed air from pneumatic system.

• Mixes air from pneumatic system and re-circulated air fromthe cabin.

HOW IS THE BASIC TEMPERATURE REGULATED BY ACSC:

• By using the lowest zone temperature demand

• By using the temperature demanded in the three zones

• By using the highest zone temperature demand

IN AUTOMATIC OPERATION, THE OUTFLOW VALVE IS OPERATEDBY:

• Only electrical motor 1.

• Electrical motor 1 or motor 2 depending on the operatingcontroller.

• Only electrical motor 3.

IN CASE OF AVIONIC VENTILATION SYSTEM MALFUNCTION:

• Air from air conditioning system is added to ventilation air.

• Air from avionic bay is added to ventilation air.

• Air from outboard is added to ventilation air

IN CASE OF DUCT TEMPERATURE ABOVE 88oC, THE HOT AIRPRESSURE REGULATING VALVE IS:

• Automatically electrically closed.

• Automatically pneumatically closed.

• Remain open.

IN CASE OF LACK OF AIR PRESSURE:

• The pack Flow Control Valve remain open.

• The pack Flow Control Valve is pneumatically controlled toclose.

• The pack Flow Control Valve is electrically controlled toclose.

IN CASE OF PACK COMPRESSOR OVERHEAT, THE PACK FLOWCONTROL VALVE STARTS:

• To close electrically.

• To open pneumatically.

• To close pneumatically.

MOTOR 3 IS CONTROLLED FROM:

• CPC1.

• The AIR COND panel.

• The CABIN PRESS panel.