What operational requirement is necessary over 20,000 feet?

For the King Air 350, one of the critical operational requirements at altitudes over 20,000 feet is the need for crossfeed capability. This is essential because, at higher altitudes, both engines operate more efficiently on the same fuel system. The crossfeed capability allows for balanced fuel management, ensuring that both engines have adequate fuel supply, which is crucial for maintaining performance and ensuring safety.

In higher altitude operations, there’s an increased risk of engine failure, and thus, ensuring that both engines can access fuel from either tank provides redundancy and reliability. This setup helps pilots manage fuel distribution effectively, especially when dealing with potential fuel imbalances that could arise during flight.

Other options, while they have their own operational significance, do not specifically address the unique challenges and requirements of flying above 20,000 feet in the King Air 350. For instance, the landing gear and flaps are generally configured for landing and takeoff, not cruise. Manual overrides pertain to the control systems rather than operational altitude requirements. Therefore, the crossfeed capability is the most pertinent requirement for safe and effective flight operations at this altitude.