What are the supplemental oxygen requirements for unpressurized aircraft?

The correct answer is based on regulations set forth by aviation authorities regarding oxygen requirements in unpressurized aircraft during flight. Supplemental oxygen is required for unpressurized aircraft operating at altitudes above certain thresholds because the air pressure decreases at higher altitudes, which results in lower oxygen levels available for breathing. Specifically, the requirement indicates that at altitudes exceeding 12,500 feet, supplemental oxygen is necessary for flights exceeding a duration of 30 minutes. Furthermore, for altitudes above 14,000 feet, supplemental oxygen is required for all occupants, and at 15,000 feet or higher, oxygen must be supplied to all persons on board.

This regulation is critical for ensuring the safety and health of pilots and passengers, as altitude sickness and hypoxia can occur when appropriate oxygen levels are not maintained. Understanding these altitude thresholds for oxygen use helps to ensure compliance with safety standards in aviation operations involving unpressurized aircraft.