L i g h t P l a n e Wor l d
If you have wondered how crop dusters deal with wind
turbines, check out this YouTube slide show of Illinois
pilot Bobby Baker at work among the turbines.
Low Ceilings and Bad Weather
Wind turbines can prevent you from flying when the
cloud ceiling is low because they raise the minimum
altitude required to clear obstacles by as much as 500
feet. Airports with limited access because of controlled
airspace or terrain will be inaccessible more days
per year if you place a forest of 500-foot obstacles on
the approach route. For turbines placed close enough
together to constitute a congested area, regulations
and common sense require 1,000 feet over the highest
obstacle. Additionally, the clouds must be another 500
feet higher because you will have moved into Class E
airspace and need to be 500 feet below the clouds. A
cluster of 500-foot wind turbines could increase the
minimum ceiling for VFR flight to 2,000 feet in that area.
Fly around them if you can.
The growth of wind farms can make a dangerous activity like scud-running even more treacherous. Sport
pilots must maintain three miles of visibility at all times
(even in Class G airspace) whereas ultralight pilots and
private pilots may fly in only one mile visibility when
down low among the turbines. I have driven through the
Red and blue shaded areas
are suitable for large-scale
wind development.
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Vol.2 N o.5 / M ay 2013
Te growth of wind farms can make
a dangerous activity like scudrunning even more treacherous.
local wind farm on the country roads during marginal
VFR conditions with dark clouds, light rain, and mist.
Those white towers and turbine blades turn dark and
blend in very well with the gray sky. Sometimes turbines
are up and running before they show up on sectionals.
Sometimes the red warning light on the tower is not
functioning. Among the several wind farms in my flying
range, there are always a few turbines that are not
lighted. Blundering into a wind farm in light rain while
scud-running could ruin your day.
Turbulence Not a Problem
It's natural for pilots of light aircraft to be curious about
wake turbulence downwind of the spinning turbines. Is
it safe to fly in their wake? Will a cluster of turbines diminish the average wind enough to affect aircraft landings and takeoffs downwind of the wind farm? Visual indications such as the photo of cloud plumes generated
at the Horns Rev offshore wind farm, west of Denmark
(published here by NOAA), led some investigators to
conclude turbine wake turbulence could be a threat to