The Investigators: High-tech crane at center of Tappan Zee collapse investigation

Wednesday, July 20, 2016
One lane of Tappan Zee Bridge remains closed after crane collapse
Investigator Jim Hoffer has the latest details.

TARRYTOWN, New York (WABC) -- As the investigation continues into the Tappan Zee Bridge crane collapse, the Eyewitness News Investigators have learned that the crane is the newest high-tech crane now being used on construction projects.

There are more cranes operating at this bridge site than anywhere in the nation and until Tuesday the huge construction project had just three minor safety violations.

Now it's the site of a major accident investigation and at the center of it, a cutting-edge, highly computerized crane.

Of the 28 cranes building the massive 3-mile long bridge, one model really stands out: the MLC-300, a new, ground-breaking, high-tech crane, known for its automated computerized counterweight system that allows for quick set-up and heavy-lifts.

Its revolutionary qualities were touted in a recent promotional video, with a crane worker saying "Assembly was very easy with the MLC300, put it up and within a day had crane fully assembled."

Now this state-of-the-art crane is at the center of an investigation after suddenly collapsing while hammering in bridge pilings.

"They're the leaders of the industry," said crane accident consultant James Pritchett.

Pritchett says Manitowoc of Wisconsin manufacturers the new MLC-300. He says they are the best in the crane business.

"They go through so much quality control dealing with these cranes. I couldn't ask for a better crane," he said.

We've learned the crane had been in operation at the bridge for a few months. Pictures from the website Earthcam shows the crane doing piling work just minutes before it collapsed.

There appears to be no problem. The question is how did this brand new crane with the latest safety technology end up in broken bits of metal.

"You have to analyze all aspects," said Pritchett.

Including looking at whether vibrations from hammering in the pilings possibly damaged the crane or was it a manufacturer defect, experts tell us however, brand new cranes rarely come crashing down on their own.

"Cranes today lift tremendous loads, high-tech, so dependent on individual operating the crane programming it correctly and run it in accordance with manufacturer specs, the likelihood of an accident is very minimal," said Pritchett.

We've learned investigators are looking closely at what role, if any, the hydraulic hammering of the bridge piles played in the collapse, specifically whether any weight-overload caused sudden stress on the crane.

Too early to tell, we're told that a team of federal safety investigators could take months to determine an exact cause.