How is the output temperature of the air conditioning system controlled?

• A. By mixing with hot bleed air to achieve desired temperature
• B. By selecting ambient temperature only
• C. By adjusting cabin humidity alone
• D. By increasing engine RPM

Answer: (A)

Output temperature is controlled by mixing hot bleed air with cooler air to reach the selected cabin temperature. The system blends the hot bleed air from the engines with cooler conditioned or ram air, using a mixer and a temperature control valve set by the desired cabin setpoint. This allows the cabin to stay at the chosen temperature even as outside conditions change. Ambient temperature alone wouldn’t maintain a setpoint, humidity isn’t the primary driver of temperature, and engine RPM doesn’t directly set the cabin temperature—the control is the blend of hot and cool air.