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Brazil Airball field

Some field in Brazil uses this.

Must not have any wind down there

thats what I was wondering. You saw what happen here to the canopies during the wind storms. That thing wouldn't last 5 minutes under that. It is open on the sides so that helps but not enough. I have done lighting designs for pro NFL teams for practice fields up north and they use an inflatable roof with re-enforcing ribs. There is also an indoor tennis facility somewhere near Charlotte NC that is acompletely enclosed inflatable held up by air pressure only. My guess is they don't use it in high wind conditions.