What is the recommended obstacle buffer ratio for helicopter landing zones?

The recommended obstacle buffer ratio for helicopter landing zones is 10:1 or a maximum distance of 100 meters. This means that for every meter of obstacle height, there should be an additional 10 meters of clear space for safe landing operations. This ratio is crucial as it ensures that there is a sufficient safety margin for helicopters during both landing and takeoff, minimizing the risk of collision with obstacles such as trees, buildings, or other potential hazards.

Using this buffer ratio helps pilots in assessing the suitability of a landing zone. A 10:1 ratio is generally recognized as a standard in helicopter operations, balancing safety and operational feasibility. Ensuring that the landing zone is clear of obstacles within this specified range allows for better maneuverability and response time in case of emergencies.

Options that suggest either lower ratios or maximum distances greater than 100 meters may not provide the same level of safety or could lead to unnecessarily large landing zones that might not be practical in operational settings. Therefore, adhering to the 10:1 or 100-meter maximum guideline is essential for effective and safe helicopter landing zone management.