An Odfjell chemical tanker destroyed a pier at a US naval weapons base due to a pilot’s error, an accident report has found.
The pilot took the Norwegian owner’s 50,000-dwt Bow Triumph (built 2015) too close to a bank on the Cooper River on 5 September 2022, the National Transportation Safety Board (NTSB) said.
The accident led to the collapse of a 300-foot section of Pier B at Joint Base Charleston’s Naval Weapons Station in South Carolina.
A Charleston Branch Pilots Association pilot was navigating the vessel, which sustained significant damage to the bow.
The report found that after making a right turn in the channel, the pilot moved the tanker closer to the left bank as he approached the next turn, a left around a bend.
The manoeuvre caused the ship to experience “bank effect” — when the bow is pushed away from the shore and the stern is pulled in.
The pilot’s subsequent rudder and engine orders could not overcome the bank effect, and the tanker struck the pier, which was on the opposite side of the river.
“Hydrodynamic forces reduce rudder effectiveness (squat and shallow water effect) and yaw the bow away from the closest bank and pull the stern in (bank effect),” the report said.
“When manoeuvring in shallow waters such as channels, shoaling can reduce the water depth below charted or expected, and therefore exacerbate the forces on a vessel,” it added.
The NTSB said bank effect can overwhelm even the most experienced seafarers.
$2.5m tanker repair bill
“Pilots, masters and other vessel operators should consider the risks in areas known for shoaling when planning transits,” NTSB added.
The Bow Triumph suffered a punctured bulbous bow and damage to its side shell, frames, and stringers in way of the forepeak ballast tank and the No 1 starboard ballast tank, which compromised the watertight integrity of the hull.
The total cost of repairs was estimated at $2.5m.
The bill to demolish and reconstruct the damaged portion of Pier B was estimated at more than $27m.
The report also revealed that an investigation has begun into Hafnia’s 38,000-dwt tanker Hafnia Amessi (built 2015) hitting the same pier on 14 January this year.
The ship had left the Ineos Aromatics Terminal and attempted to make the same turn at the bend.
The US Coast Guard is working with stakeholders to determine appropriate long-term solutions to reduce the risk of casualties at the location, NTSB said.
In the interim, ships of more than 10,000 gt are to use a tethered two-tug escort, it added.
In 2017, the Bow Triumph was one of three ships that grounded off Durban, South Africa, after a severe storm.
Port authority Transnet said the tanker was refloated at Island View berth 4.
The ship has insurance cover through Gard in Norway.
Odfjell has been contacted for comment.
Hafnia told TradeWinds: “We can confirm that the Hafnia Amessi experienced an allision with the US Navy Pier Bravo on the 14th of January 2024, due to navigational conditions of the waterway.”
“Other than some grazing on the starboard side of the vessel and the side of the pier where contact was made, there was no harm to the crew, nor to the environment or the cargo,” it added.
