http://4.nbcny.com/tqzSWMH
Sounds like they were lowering the jib... wind for sure, ice buildup maybe, or just operator error?
They were lowering the lufting boom as a safety measure and the wind caught it and acting like a lever, flipped the rig, laid the 565' boom down the center of the street. Watch the video and you see the steam clouds blowing with the boom, very windy today in Manhattan. 320 ton rig, looks like a Manitowoc, one of Bay Crane's.
It also appears like the main boom was pretty low when they tried to lower the upper jib creating a long lever.
This. Obviously second guessing the poor b*****d in the seat but it looked to me like the main boom should have been straight up once the luffer got over about 10 degrees down from vertical. Gusty winds are a nightmare though, can just as easily lose her over backwards.
I can't begin to imaging the wind gust that must get funneled down between those tall buildings. One thing to be working out in the middle of a open field with gusty wind but who know which way the wind will shift in a matter of a couple minutes in that kind of area. And could be very different at ground level compared to top of the boom.
Isn't it incredible that only 1 person was killed with 500+' of boom and jib falling in the city? How large of a CAZ is typical when using a crane of this size?
Probably would have been zero except the poor guy was sitting in his car, never saw it coming. They said the workers were diverting traffic to clear the area as a safety measure. I would imagine there was a lot of hollering and safety vests flapping in the wind, it took quite a few seconds for that much boom to make it to the ground after the crane operator had done his Elvis impersonation.
I think I agree with lantraxco about the main boom angle. I couldn't tell from my screen but it kind of looked like the main boom was coming down at the same time as the luffer to start with. No matter what happened though it was tragic.
On this LS-298 Linkbelt I had 190' main boom/luffing boom and 200' of luffer. In order to knife this luffer down I had to set main boom @ 65 degrees and then I could knife the luffer down. The critical thing about this Linkbelt is at a certain point it is necessary to bypass computer to get the luffer tip on the ground. That means if the main is not at right angle and I start down on the the luffer, saftey limits would not stop me. and crane could potentially tip with no way to recover. Looking on Bay cranes web site they have a Liebherr 1400 with same colors and color pattern on counterweights. I wonder if you have to bypass computer on the Liebherr to get the luffer knifed down also??
Another thought I had was I didn't see a wheel horse on that rig. Is that something that could have been necessary for that size of rig in those conditions?
I was just looking on instagram it seems that they had two of those cranes (the same model)in one of the pictures it showed two steel wheels on the tip .It also had a pic that said they had the street closed for 72 hr's strait to assemble it .Someone made a comment that they where trying to get it down because of wett sticking snow/ice and high wind condition's. At least it fell down the street and not across or through the buildings most likely would have been a lot more people hurt or killed. I also thought about having to bypass the safety/overloads if you have ever seen one of those go up it looks like it's almost a seat of the pants move to feel when to start lifting the jib off the ground imagine trying to let it down in high wind and icing conditions. Also seen a comment that it took 30 trailer lds.
I would not expert to see a wheel horse, Maxxer, or whatever rear further counterweight system where they were. They were operating nearly straight up so weight when working the crane was probably not an issue. The rigs we used had to have the main boom locked in one of three positions and the computer matched up or the jib, and hoist would not work. Not sure what others have for erection sequence but normal the luffer hangs stright down before lowering the boom. Anybody remember when Manitowoc lost that boom over backwards on the first 21000 every built. It was at the factory. 1999 I think. It had 580 ft of boom and luffer if I remember right. They were working out the erection sequence when it happened. As they stated in the press release thats why they test at the plant. No one was injured.
Wheels on the tip are often used on the luffer jib. When they get it folded so it is hanging straight down they boom dowm until the tip is at the ground and then let it roll out as they boom down. They shed a few tons of weight that way.
I was thinking thats what John c. was talking about until you mentioned Maxxer.
Now I have never been known as a brain surgeon but my biggest issue is this. Who the hell thought up the plan to put over 500 feet of luffer and boom configuration in a 1300 Liebeherr. (1300 are a 300 ton class machine) Just because liebeherr says it can be done does not necessarily mean lets do it in the middle of Manhattan. My point being when you max out a machine with max stick and jib every thing needs to be perfect. The fantasy land that I live in has so many pitfalls. I wish every one the best and my sympathies. But god Dang management pull your head outta your rear.
I'm not a crane guy, though I have passing familiarity with some and understand the basic principles. I was thinking the same thing though, these machines with extremely long boom configurations are really pushing the limits, one wrong move or wind gust and you're done. 500 feet of boom on a crawler base, it's like watching that guy juggle while standing on a board placed on top of a bowling ball. Half a degree off bubble and she's down. I was watching a video of a mobile unit setting up to erect a wind generator the other day, it took two smaller cranes to help the boom and luffer off the ground until the angle was high enough to balance out. Of course I saw one instance where the same operation occurred and something went wrong, all three cranes bit the dust and lots of riggers were scrambling out of the way.
I know nothing about cranes but I like them. When going down into the knife position where is the block placed as I have never been close enough to figure this out. As one would not want the cables in the dirt. Thanks
OK, what is a better alternative to a crawler with a luffing jib, to lift stuff on a narrow street in Manattan? Is there something better that is temporary?
A stiff leg crane on the roof would be the only alternate I could think of. Even with that you would need a smaller one erected on the roof to lift and assemble the larger one if the air handlers had much size to them which I would expect in a large building. Take some big cable drums on the stiff leg also.
I've heard of plenty of helicopter lifts. Can't see how that machine with all that stick out could lift much more than a Chinook could.
I can only imagine the logistics and permitting required for helicopter lifts in a crowded airspace like NYC. That could possibly be more red tape and cost than a large crane. Maybe someone who knows could post an answer.
Skycrane if you need it, but they're hella spendy. Rubber tired rig with outriggers, or a ringer crane or crawler with the counterweight on wheels. Block the damn street and let the good citizens bitch, it's for their own safety. We need some new engineering thinking for these tall buildings, it isn't just the lifts, you literally can't fight fire or evacuate people well above about ten floors, there's just got to be better ways.
A lot of it is the ego thing, some just have to brag "Mine is taller(bigger) than yours!"
I agree Lan. Building design should take this stuff into account. Only just in the past 10 years or so are better building designers starting to join ILPD projects and think in a different mode. In ILPD (Integrated Lean Project Delivery)projects the engineers design first, the structural second, and the architects design around that shell last. Of course there is push and shove but by designing the air handling systems and other utilities and there routing first so they work as they should, and work efficiently, the buildings take less maintainance and work much more efficient. They also are designed with long term maintainence in mind as the contractors are part of the design team. I have done two hospitals with ILPD design and 100% 3D modeling and there is no comparision to normal old hat design and construction. They came in cheaper per sq ft also with not many change orders.
Worked with the genset guys that were installing new emergency sets in a hospital expansion. The original gensets were installed in the basement of the old building with a crane and then the rest of the building built over it. Good thinking. After excavating, pouring slab and walls for a new basement, saw cutting the old wall, lots of fun removing the old gensets, installing and rewiring the new gensets, sealing everything back up.... During the test run everything went according to plan until they were about thirty minutes into a load test and the first genset began to overheat.. second one came online automatically which was the good news part of the bad news... but then the second unit shut down after only about ten minutes. Hmmm.... oh, ambient was too hot to walk into the room? Guess somebody should have thought about the ventilation not being adequate to double the genset size? Jackhammers all around. Then there were the two sad looking fellows that got me out of bed one winter night to go open the CAT store and sell them a hundred pound battery. They were the maintenance men for a high rise apartment building in downtown Portland. Winter storm took out the power, backup generator was.... on the roof. No start, dead battery. No power, no elevators. They had already walked up many flights of stairs to go up and check on why the generator had not come on automatically and back down again, in the dark. Now they got to do it gain, carrying an 8D battery between them. Again, good thinking.
Today is a particularly fitting day for me to sympathise with those fellows. I am working at a defunct coal power station, removing scrap metal and surplus equipment (a very good deal all around). Except we have to use an elevator and it quit workin several times today. Each time I had to go to 6th floor (equivalent to 10th floor in regular apartment construction, tall ceilings) and put in new buss fuses. The plus is I I had A LOT of exercise and I know for sure I do not have heart disease!
Google 60 Hudson Street NYC, this was the Western Union Building built between 1928 and 1930. Look at he building and you will see why the were using that crane.