That dangling tower crane

It’s possible that by the time I get this posted, the “dangling tower crane” in Manhattan that’s been threatening to fall in Sandy’s winds will have already carried out its threat.

The best photo of it I’ve seen is this one from a Pennsylvania TV station.

Dangling tower crane

Source: WJAC-TV

And here’s a detail of the crumpled boom.

Dangling tower crane detail

Source: WJAC-TV

The news reports I’ve seen have referred to the crane as “collapsed,” which is at least partially true, but they’re missing what I see as the most interesting fact. This appears to be a luffing crane,1 in which the boom—the long latticework part that carries the load—has been pushed over backwards.

Here’s a luffing crane in better circumstances.

Luffing crane

Source: De-Ying

You can see by comparing the photos that what’s weird about the Manhattan crane is not simply that its boom has been damaged and is dangling—it’s that it got flipped around clockwise and bent backwards. It’s now hanging off the opposite side of the tower from where it started. I’ve seen plenty of cranes with broken booms, but I’ve never seen that.

Update 10/30/12
Finally found what I was hoping to show last night when I first posted this: a video of the boom flipping over.

If you know of a better version, shoot me a link to it.

  1. If you’re a sailor, the terminology of cranes will be familiar to you. I’ve already mentioned the boom and luffing. Cranes also have a mast, which is the solid black thing sticking up and to the right in the photo of the dangling crane and the solid yellow thing in the same orientation in the photo of the example crane.