Turbulence Analysis
Recap my post #25
CASA AC139.E-05v1.1
2.2.6.3 Turbulence is a risk to aircraft and aerodrome operations. Studies have proven that for wind turbines of less than 30m Rotor Diameter (RD) the wake vortices will impact aircraft located up to 5 RDs downwind and 2 RDs vertically….
The TTWF RD is 600ft.
Laterally 5RDs is 915m and 2RDs vertically is 1,200ft.
The vertical extent of turbulence can meander vertically as depicted here…
Consider that the 2RD vertical range of turbulence has meandered to be one RD above the WTG tip, thus turbulence would extend to an elevation of (1,155+600) 1,755ft AGL or, 2,545ft AMSL as shown here…
Wind turbine wake turbulence is considered a hazard, not an obstacle. Hence, wake turbulence may extend into and above the mandated 500ft obstacle clearance buffer.
To date, Acciona is silent on the intensity and nature (shear, speed, gust) of the TTWF wake turbulence.
For safety, would it then be prudent to declare a 1,000ft buffer above the WTG tip height? If so, then the required overfly height above the airport would be 2,155ft. The required aircraft climb gradient then becomes 2,155/18,228 or 11.8%. The overfly altitude is therefore 2,945ft AMSL.
Previously reviewed aircraft take off requirements would need to be reconsidered and also what would be the impact on the 2,500ft (non mandatory below 3,000ft) westerly hemispherical?