26.04.2016
Manhattan boom drama
A 135ft boom lift caused a stir in Manhattan, New York yesterday after its platform broke a window and began to tilt.
Please register to see all images
The platform ended up pushing through a window on the building
The lift a Genie Z-135/70 owned by United Rentals, was raised to a height of around 18 metres or so and, according to one witness, the boom descended gradually towards the building, suggesting that it simply leaked down. However the platform finally contacted the building and broke a large glass window but then began to lift the nearside wheels off the ground.
Looking at the photos that we have received overnight it looks as though the riser or lower boom might have crept down a little, rather than, or as well as the main boom? But it is not possible to tell based on the information that we have received. Some say that the platform was left elevated while unattended, yet the fact that two wheels lifted off the ground suggests power was applied- although it could just be compatible with the lower boom leaking down?
Please register to see all images
The recovery begins
The fire crew reported that it placed blocks under the raised wheels and then with the help of United Rentals were able to bring the machine down into the stowed position under its own power, and blamed the incident on a hydraulic failure. No one was hurt in the incident, which appears to owe more to a lift being left elevated while unattended than anything else - although there might be more to the story.
Please register to see all images
All stowed and safe with no harm done
Vertikal Comment
While hydraulic boom creep down is a lot rarer today, than it was 30 years ago it does still occur from time to time, and therefore it is always best to fully stow a machine when out of service, or ensure that nothing is in the path of the boom should it creep down overnight. And any machine with a restricted working diagram needs to be brought back into a position where it will retain stability regardless of any creep down. i.e. with telescopic booms fully retracted. This is certainly a strange incident.
I do not speak on behalf of Genie, but Don't blame the manufacturer for this incident. Have a good look at the photos. The wheels are on an incline (on the footpath, leaning away to the road, with the chassis looking to be close to maximum backwards tilt. The tower boom is retracted and at 45 deg and the upper boom is retracted and at 45 deg. The centre of gravity is working toward the tipping point. The site setup is wrong and the Z135 is too close to the building. Why have wheels on the footpath? Where is the support if there are voids in the footpath? Look at the Genie Z135 specification sheet, this boom needs to be at least 22ft from the wall and the wheels on the level road surface that can support the road. Prosecute the users and operators for incorrect setup and limited product knowledge. And the answer is YES, I have seen this same issue in other brands, Genie, Snorkel, JLG, Grove etc, setup too close to the vertical work surface.
AccessibL
I'd like to see the CCTV! Wheels off the ground doesn't sound like a boom creeping down; climbing out (or in?) through the window sounds like a reasonable way of avoiding blame.
Badly adjusted boom speeds can make the wrong boom move first. Coupled with the fact that the basket level can be very disorientating, and feel to move in a counter direction, and the articulation being opposite to smaller, more commonly used machines, I reckon the operator did it!
Was anything gained by blocking the wheels? I don't quite get that. Can anyone explain?