Stage Collapse at State Fair

[Grace]

I assume these creations are aluminium framing with lots of canvas draped over them ???

No, they were steel.

Indiana Governor Mitch Daniels called the collapse "freakish," saying at the news conference that a storm was anticipated but the blast of wind that whipped through the grandstand area was unexpected.

I also heard that the stage area was the only place in the fairgrounds that had this particular strength of wind gust. Estimated to have been 70-75 mph - like a Category 1 hurricane or EF1 tornado.