Fears have re-ignited in southwestern Ontario after a fatal plane crash involving a wind turbine in South Dakota that left four people dead.
Garry Sheperd has been flying for over 30 years. He's a seasoned pilot, and he's not pleased about the wind turbines he's now sharing the skies with.
"The ones we've got coming to our backyards here are 400 feet at present, but the new generation are 500 feet. In Europe they're over 700 feet and it's just a matter of time before there's a conflict."
Four men were killed in April after their plane apparently collided with a wind turbine in South Dakota during foggy weather.
And Sheperd fears that he and his fellow pilots are just as at risk, especially those flying in and out of the Kincardine Municipal Airport, where 10 of 92 soon-to-be-built turbines in the Armow Wind farm could be flight risks.
"We pilots have been adamant that these aircraft and these turbines don't mix."
But the company disagrees, Jody Law of Pattern Energy says, "At Armow, we have worked closely with the federal regulatory agencies to ensure that the project will be in complete compliance with all safety regulations and standards."
In fact, the Armow Wind farm has been approved by all provincial and federal bodies.
But it's not just the size or the fact they are spinning that concerns pilots. Sheperd explains it's an invisible force unique to turbines that can cause problems flying past.
"As the blades turn there are vortices that come off them and rotate downwind...so we're climbing up through that invisible hazard and we shouldn't have to do that."
Eight turbines near the Chatham airport were ordered removed by Transport Canada last June for safety issues, but remain standing.