What is the difference between the normal cabin differential pressure and the maximum cabin differential pressure?

What is the difference between the normal cabin differential pressure and the maximum cabin differential pressure?

• A. 0.1 psi
• B. 1.0 psi
• C. 0.5 psi
• D. 2.0 psi

Answer: (A)

Cabin pressurization is kept within a tight band: the system maintains a normal differential pressure as the operating target, while there is a certified maximum differential pressure that the airframe must never exceed. The difference between these two values is the small margin built into the system to cover sensor/valve lag, measurement errors, and transient changes in altitude or temperature. That margin is about 0.1 psi, making the gap 0.1 psi. The larger margins listed in the other options would imply a much bigger safety buffer than what the system design specifies.

Cabin pressurization is kept within a tight band: the system maintains a normal differential pressure as the operating target, while there is a certified maximum differential pressure that the airframe must never exceed. The difference between these two values is the small margin built into the system to cover sensor/valve lag, measurement errors, and transient changes in altitude or temperature. That margin is about 0.1 psi, making the gap 0.1 psi. The larger margins listed in the other options would imply a much bigger safety buffer than what the system design specifies.