General Authority of Civil Aviation (GACA) Aeronautical Information Publication (AIP) Practice Exam

Under what condition does the air cleaner work in "AUTO" mode?

1. When operating in high altitude

2. Below 7000 ft with the applicable pack operating

3. When the system is malfunctioning

4. Only during maintenance

The correct answer is: Below 7000 ft with the applicable pack operating

The air cleaner operates in "AUTO" mode below 7000 feet when the applicable pack is functioning. This mode is designed to automatically adjust the air cleaning process based on the operational environment and the needs of the aircraft. At higher altitudes, the air density and quality can significantly change, necessitating different handling; thus, the system relies on the packs to maintain proper air flow and quality. Operating below 7000 feet means that the air pressure and other environmental conditions are stable enough for the automatic systems to effectively manage air cleanliness without the need for manual intervention. In this scenario, the system can efficiently detect and respond to changes, ensuring optimal performance without requiring constant oversight from the pilot or crew. This mode enhances safety and convenience during aircraft operations in lower altitudes where air quality can be crucial to passenger comfort and system function. Other conditions, such as system malfunctions, would typically require manual override or troubleshooting rather than relying on "AUTO" mode, and maintenance is a controlled environment where automatic functions may not be applicable.