Horns Rev ofshore wind farm, west of Denmark.
aviation. It was a serious enough concern that a German energy company commissioned a scientific study
for a wind farm planned near a microlight airfield near
Boslar, Germany. The research news website Science
Daily reported the results in its "Wind Farms: A Danger
to Ultra-light Aircraft?" article. A sophisticated computer model predicted the turbulence would be no different
than the natural background turbulence, whatever that
means. Field measurements downwind of turbines were
said to confirm their computer model. More convincing
are real-world reports by local pilots and friends who
have deliberately flown ultralights or light planes in the
turbine wake. No unusual turbulence was found. All
agreed mechanical turbulence from ground objects like
buildings or trees was stronger than any bumps found
in the turbine wake. One ultralight pilot suggested the
turbulence may actually be greater when the turbine
blades are stationary! By making careful tests in very
smooth stable air with my single-seat trike, I was able to
identify very light bumps located just where you would
expect wingtip vortices. They would bother only the
lightest ultralights and only if landing close behind the
wind turbine.
Airports at Risk
Wind turbine farms are a threat to both public and
private airports because of the money involved. Some
public airports have already been threatened with
closure simply because their presence interferes with
a proposed wind farm. The average small town airport
is not a major source of revenue and may actually be
an expense to the city or county that owns it. Wind farm
development can bring hundreds of thousands of dollars
annually to the local school district in property taxes
and provide royalty payments to landowners of $7,000 to
$9,000 per turbine.
Developers understand they need to maintain good relations with landowners and will adjust turbine locations
to accommodate owners needs, including those with
established private restricted landing areas. Unmarked,
unrecognized private ultralight airstrips are more vulnerable. One wind turbine off the end of your runway
will put your neighbor's kid through college.
» Please send your comments and suggestions to
dgrunloh@illicom.net.
Dan Grunloh, EAA 173888, is a retired scientist who
began flying ultralights and light planes in 1982.
He won the 2002 and 2004 U.S. National Microlight
Championships in a trike and flew with the U.S. World
Team in two FAI World Microlight Championships.
EAA Experimenter
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