What is the speed that provides the longest power-off glide range?

The speed that provides the longest power-off glide range is known as the best glide speed. This speed is determined by taking into account the aircraft's lift-to-drag ratio, which is maximized at this specific speed. When an aircraft is gliding, it seeks to cover the greatest horizontal distance while losing altitude.

At best glide speed, the aircraft maintains an optimal balance between lift and drag, allowing it to achieve the most efficient descent. Flying at this speed helps ensure that the aircraft is neither too slow to maintain adequate lift nor too fast, which would lead to increased drag and reduced glide performance. Therefore, the best glide speed is critical in situations where an engine failure occurs, enabling the pilot to maximize the distance traveled before reaching the ground.

While other speeds mentioned may provide options for different flight regimes, they do not optimize glide performance in the same way as best glide speed does. The emphasis on maximizing the glide range in a power-off scenario highlights the importance of maintaining that specific airspeed for safety and efficiency during an emergency descent.