Seems the 'research' is all over the place. Probably reflects who is paying for the research..
Direct Impact - Physical
• Turbulence
– Current CAA guidance in CAP 764, Ch 2, Para
2.46:
“research shows measurements at 16 rotor diameters downstream of the wind turbine indicating that turbulence effects are still noticeable”
– Poorly understood but research ongoing – Significantly greater impact on slower and lighter aircraft
http://airspacesafety.com/wp-content...t_FINAL_V1.pdf
Or if the funding comes from the "Dutch Ministry of Infrastructure and the Environment" the distance is 6 rotor diameters for helicopter ops..
Offshore wind turbine suction and safe helicopter operations | European MSP Platform
Although, a retired EMS helicopter pilot has a different view from practical experience...
With the information that you have been provided on the current size and type of wind turbine, what would you consider to be a safe travel corridor width needed to allow for the EMS helicopter service to safely fly to and from Calumet Memorial Hospital?
"One Nautical Mile would be to narrow. It would not allow for safe flight path even down the middle because of the influence of turbulence created by the Wind Turbines on either side. Even without the influence that air turbulence would have on the aircraft. You must provide room for safe travel, as well as to allow for a safe normal speed turn to be made. I would say that a clear flight path corridor should be a minimum of 1 ½ nautical miles, with 2 miles being the preferred distance..."
Better Plan: The Trouble With Industrial Wind Farms in Wisconsin - Today's Special Feature - 12/27/08 H is for HELP! ---What Did the EMS Helicopter pilot say about rescues near wind turbines?
Of note re comparing helicopter operations to fixed wing ops: Due to the high wing loading of a helicopter I have happily flown a mustering helicopter (
Not a Robinson) in turbulent conditions that I would not have operated a fixed wing aircraft.
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