At what cabin altitude will passenger oxygen flow automatically if the valve is set to AUTO?

• A. 12,000 feet
• B. 13,000 feet
• C. 13,500 feet
• D. 14,000 feet

Answer: (C)

Automatic passenger oxygen flow is driven by the cabin altitude sensor when the valve is set to AUTO. The system opens the flow to passengers at the aircraft’s specified auto-activation point, ensuring oxygen is available before hypoxia becomes a risk as altitude increases. For the PC-12 NGX, that activation point is 13,500 feet. So once cabin altitude reaches that level, oxygen starts flowing automatically. Below that altitude, it remains off. The other altitudes listed do not match the NGX’s auto-activation setting.