At what height above the runway does the dry runway balanced field length (BFL) end?

The dry runway balanced field length (BFL) is a critical parameter in aviation that represents the distance required for an aircraft to become airborne after initiating takeoff and to come to a complete stop in case of an aborted takeoff. This concept is essential for ensuring that an aircraft can safely operate from a given runway under specific conditions.

In the context of the Falcon 7X and its operational performance, the BFL is defined at a specific height above the runway, which is crucial for pilots during takeoff calculations. The correct height at which the BFL ends is established as 35 feet above the runway. This altitude signifies the point at which the aircraft has reached a critical speed and can safely continue with the takeoff if an engine fails or other issues arise.

Choosing 35 feet provides a buffer above the ground that takes into account various safety and performance factors, such as aircraft climb capabilities and the need for a safe margin during the transition from ground to air. This is particularly important for larger, heavier aircraft like the Falcon 7X, which require precise calculations related to their specific aerodynamic characteristics.

Other heights, such as 20, 25, and 30 feet, do not accurately reflect the established performance metrics for the Falcon 7