Instrument Flight Rules (IFR) Practice Exam 2026 – The All-in-One Guide to Master Your IFR Certification!

In unpressurized IFR flights above 15,000 feet, all passengers must have supplemental oxygen for the entire flight due to the reduced atmospheric pressure and associated decrease in available oxygen at higher altitudes. At altitudes above this level, the risk of hypoxia increases significantly because the partial pressure of oxygen is insufficient to meet the physiological needs of the human body.

The regulation mandates that when an aircraft operates above 15,000 feet MSL, each person onboard must be provided with supplemental oxygen, indicating a standard of safety that emphasizes the necessity of ensuring that both crew and passengers remain in a safe oxygen environment. This requirement is critical in preventing cognitive impairment or loss of consciousness that can occur due to hypoxic conditions, thus prioritizing the health and safety of everyone on the flight.

Understanding the specific altitude thresholds for oxygen requirement is essential for IFR operations, making it imperative for pilots and operators to adhere to these guidelines to maintain operational safety and comply with regulatory standards.