ABS: El Faro Hull Strength Measure Exceeded Standards

Faro
Image courtesy NTSB

By MarEx 2016-05-20 21:07:32

The U.S. Coast Guard Marine Board of Investigation's hearings into the loss of the El Faro continued Friday with testimony from American Bureau of Shipping (ABS) officials Thomas Gruber, the former head of the stability group, Suresh Pisini, head of the structures group, and Dan Cronin, former VP of operations. 

Pisini and Cronin testified on the vessel's strength characteristics. Cronin told the panel that from 2006 to 2011, ABS surveyors noted and monitored “substantial corrosion” – defined as corrosion within the allowable wastage limit, but approaching the limit – on unspecified areas of the El Faro's structure. As gauges of wastage approach the limit, these areas must be gauged and surveyed annually, he said, and over that five year period the ship was inspected 12 times with attention to the affected elements.

By 2011, through a combination of replenishment and reinforcement, the corrosion was fully addressed: rider plates, brackets and steel replacement were sufficient to resolve the problem, Cronin said. He added that he did not believe the added weight from the reinforcements would have been significant.

In followup questioning, Cronin discussed a post-accident buckling strength assessment ABS performed for the El Faro based on gauged (surveyed) steel thicknesses. With those gauged values, the vessel passed all buckling test standards for new ship construction – both the standards for newly built vessels in 1973 and for newly built vessels in 2015. Pisini said that he was "quite confident" that the El Faro would not have exceeded limits for bending moments, even if heavily loaded.

The panel also asked the ABS officials whether the 2014 addition of fructose cargo tanks on the El Faro had been taken into account in her stability and structural evaluations. "The review was just limited to the underdeck structure in way of the fructose tanks and we have not seen any loading manual or any trim and stability booklet with updates” from the addition of the tanks, Pisini said. However, Gruber said that the tanks would not have had an impact on stability tests even if they had been taken into account: “For the requirement of the stability test, it was not a deciding factor. It would not have required a new stability test or deadweight survey,” he said.