What is the maximum cabin altitude?

• A. 12000 ft cabin altitude
• B. 8000 ft cabin altitude
• C. 6000 ft cabin altitude
• D. 10000 ft cabin altitude

Answer: (B)

Cabin altitude is the effective altitude inside the aircraft cabin that the pressurization system maintains for passengers and crew. The maximum cabin altitude is the highest altitude the cabin is allowed to reach during normal operation, chosen to keep oxygen levels comfortable and reduce hypoxia risk.

Most transport-category aircraft are designed to keep the cabin at about 8,000 feet or lower, even when flying at much higher outside altitudes. This level provides enough oxygen and reduces fatigue and discomfort on typical flights. Higher cabin altitudes would increase the chance of hypoxia during longer exposures, which is why 8,000 feet is the standard maximum. That’s why the best choice is 8,000 feet.