Help me identify the big metal thing I saw on the highway

February 28, 2014 7:05 AM

A few days ago, as I drove down I-69, I saw two semi trucks heading in the opposite direction. Each transported a long, narrow metal object. I would estimate each object was the length of three semi truck trailers. It mostly resembled a knife blade in color and shape - something like a chef's slicing blade. It seemed to look serrated toward what would resemble the tip of the knife. What the heck were they transporting?
posted by rikhei to Grab Bag (10 answers total)

Possibly vanes for wind generators? I see them from time to time being transported along I-40 as well and they are gigantic.
posted by jquinby at 7:10 AM on February 28, 2014

Wind turbine blades came to my mind too, although the serrations don't sound right. Large components of bridges and other civil engineering projects are sometimes transported this way.
posted by werkzeuger at 7:11 AM on February 28, 2014

Seconding what jquinby and wekzeuger said. Did it look something like this?
posted by DeWalt_Russ at 7:13 AM on February 28, 2014

Did it look like this?

The serration might have just been the hazard stripe sack slipped on the end of the vane.
posted by JoeZydeco at 7:14 AM on February 28, 2014

I've heard of turbine blades being textured too, so that would explain the serration:

Whale Fins Influence Wind Turbine Design
posted by Think_Long at 7:22 AM on February 28, 2014

Could they be bridge structure?
posted by tilde at 7:38 AM on February 28, 2014

I think you guys are right - I think they were wind turbine blades. I may have misinterpreted something as serration when maybe it was something else - I didn't get a sustained look at them since they were heading in the opposite direction, and there was a good chunk of land between the two sides of the highway.

Thank you for assuaging my curiosity! :D
posted by rikhei at 7:48 AM on February 28, 2014

When I have seen turbine blades in transit on the highway, there is almost always more than one, and they are separated from each other by less than a mile, like a convoy.
posted by werkzeuger at 8:19 AM on February 28, 2014

I wonder if the perceived serration near the tip might have been a tarp pulled by multiple cables/cords.
posted by Good Brain at 10:15 AM on February 28, 2014

Yes, serrated edges are the new hotness in wind turbine blades. The new 3+ MW class machines often have them to break up tip vortices and manage radial flow along the blade. They may also help with noise, too.

(wind turbine person here …)
posted by scruss at 6:26 PM on February 28, 2014