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Aviation glossary

Best Glide Speed

What is best glide speed?

FAA handbook figure illustrating best glide speed

Best glide speed is the airspeed that produces the least altitude loss over a given horizontal distance, allowing you to glide the farthest without engine power. It corresponds to the best lift-to-drag ratio (L/D), where the aircraft is most aerodynamically efficient. Any deviation—flying too fast or too slow—steepens your descent and shortens your glide range. Think of it as the speed that buys you the most distance per foot of altitude when the engine quits.

Also known as: best L/D speed, best lift-to-drag speed, maximum glide speed

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