Define the operating limits for Np during cruise.

During cruise flight in the T-6, the operating limits for the propeller rpm (Np) are established to ensure optimal performance and engine safety. The correct range for Np is from 2,000 to 2,500 RPM. This range is specifically designed to allow the engine to operate efficiently, providing enough thrust while maintaining engine temperatures and pressures within safe operating limits.

Operating within this range helps prevent excessive wear on the propeller and engine components, promoting longevity and ensuring reliable performance. The choice reflects the balance between power output and fuel efficiency needed during cruise conditions, while maintaining adherence to safety regulations and operational guidelines.

Choosing limits outside this range may lead to undesirable conditions, such as decreased engine performance or potential mechanical failure, which would compromise the safety and efficiency of the flight.