At what altitude is the Envoy 175's airspeed limit reduced due to compressibility effects?

The correct answer is that the airspeed limit for the Envoy 175 is reduced due to compressibility effects above 10,000 feet. This phenomenon occurs because as altitude increases, the air density decreases, and aircraft experience different aerodynamic behaviors as they approach higher speeds. Compressibility effects become significant as the aircraft approaches the speed of sound, typically considered to be around 10,000 feet in many aircraft types.

At this altitude, the airflow over the airfoil alters significantly, leading to the potential for shockwaves and other compressibility-related issues. Reducing the airspeed limit helps ensure safe operational conditions and prevents control issues that may arise from these effects. Understanding this altitude threshold is crucial for pilots as it affects how they manage their speed and maintain safety during flight.