What does Power Margin refer to?

Power Margin is defined as the difference between power available and power required. This concept is critical in aviation because it helps assess the performance capabilities of an aircraft under various conditions. By understanding the power available, which includes the total power that the engines can produce, and the power required for specific tasks, including overcoming drag and maintaining altitude, aircrew can determine if the aircraft has sufficient power to perform required maneuvers or climb rates, especially in critical phases like takeoff and landing.

A positive power margin indicates that the aircraft can safely execute its required tasks, while a negative power margin signals a potential shortfall, which could lead to performance issues. This measurement contributes to overall flight safety and operational efficiency by ensuring that the aircraft operates within its limits, particularly when conditions may change unexpectedly.