The maximum flap extension altitude is 21,000 feet. What is the correct value for this parameter?

• A. 21,000 feet
• B. 25,000 feet
• C. 18,000 feet
• D. 30,000 feet

Answer: (A)

Flap extension altitude is the upper limit at which the flaps may be deployed safely. This limit protects handling qualities, stall margins, and the flap system’s structural and aerodynamic limits in high-altitude, thin-air conditions. For the P-8A, the published maximum flap extension altitude is 21,000 feet, so extending flaps any higher would be outside the approved operating envelope. The other options would either exceed or fall short of this established limit, which is why 21,000 feet is the correct value.