“Saw on local news last night they will not tether the cranes. Instead, they will let them swing with the winds like a weather vane.”
Not a good idea.
https://www.liveleak.com/view?i=e5d_1504754266&comments=1
Actually on tower cranes they have to let them swing in the wind. If they leave the boom fixed or try to tether it the boom acts like a sail and brings the tower down in the later case or twists it down in the former case.
Company I was with 23 years ago had a luffing boom on a track mounted crane (almost as big as a ‘ringer’) and they left it partially locked one night and a tornado hit it. The near vertical boom tried to rotate around, brooke the king pin and came down on the hospital alongside of it.
I had a 175 foot boom on my last project. I actually had it pre-set up for a lay-down, which is something they are not designed to do, but I was on an air base and did have to do it during a microburst. We had cribbing pre-stacked in a shut down street at 50’ intervals.
No crane is set for 185 mph winds.
As you predicted, the first tower crane has collapsed in Miami.
As I said in my first reply, these are often unable to withstand something like this wind speed.