Investigation Of The September 7, 2011 Collapse of a Mobile Crane at the National Cathedral Site in Northwest Washington, DC

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A 500-ton Liebherr mobile crane collapsed amid thunderstorms and heavy rain while it was being lowered to the ground. The crane's telescopic boom was 152 ft. and the attached lattice jib was 276 ft. long. The crane had been delivering materials over the cathedral building after earthquake damage. The crane tipped, overturned and fell its full length. One worker injured. Back to Top