CMA CGM Boxship Hit Beacon Due to Lack of Crew Understanding and Procedures
Lack of proficiency in the steering gear operation and change of control modes due to ambiguous procedures caused a containership to strike a navigation beacon while departing the Port of Melbourne in May 2023. The Australian Transport Safety Bureau (ATSB) released its report saying it found an incomplete understanding of how the steering gear operated among the ship’s engineers and ambiguous language in the company’s fleetwide procedures.
The boxship CMA CGM Puccini (6,300 TEU) was transiting the Yarra River in Melbourne, Australia on May 25, 2023, when it hit a navigational beacon. The initial investigation showed erratic behavior by the ship leading the ATSB to investigate why the steering gear was not performing correctly. The 2004-built ship, registered in Malta went off its intended track towards the edge of the navigable channel causing it to strike the beacon. The pilot aboard and the crew reported the rudder was responding erratically to helm orders.
Investigators pieced together the cause of the erratic steering, determining that it was due to a hydraulic bypass valve being left open by the crew after an AMSA port state control inspection the day before the incident. This resulted in the steering system hydraulics being incorrectly configured for normal operation.
It was established that with the hydraulic bypass valve being left open, the steering operated sufficiently well with minimal load on the rudder to pass pre-departure visual inspection. However, when the hydrodynamic loads on the rudder increased, with increasing ship’s speed and rudder movements, the open bypass valve allowed leakage of hydraulic oil and system pressure around the pump leading to erratic response of the rudder.
CMA CGM Puccini severely damaged the beacon while departing Melbourne, Australia (ATSB)
ATSB determined that several officers on board were not as proficient with steering gear operation and change of control modes as was required by regulations. The situation was complicated by the fact that the steering terminology used on board and within the CMA CGM fleet was not clearly and explicitly defined. For the giant shipping liner, the official fleet terminology was “steering gear failure” and did not recognize common industry terms such as “emergency” and “local steering.”
“The ship’s responsible officers had an incomplete understanding of how the steering gear operated, and therefore incorrectly configured the steering system hydraulics,” said Angus Mitchell Chief Commissioner. The report notes they were unaware of the dangers and further AMSA told the investigators manipulation of the steering hydraulics was not required for the demonstration during the inspection.
The ATSB final report on the incident shows that in the early hours of May 25, CMA CGM Puccini sailed from Swanson Dock in Melbourne after route safety checks under the conduct of a pilot and initially with two tugs in attendance. During the turn to leave Swanson Dock, the master and chief mate noticed that the rudder response appeared sluggish, as if only one steering pump was running (both pumps were operating). Neither raised their observations with each other, or the pilot, and there were no alarms to indicate a pump had stopped or other abnormal conditions.
By 0436, the ship was moving along the channel in Yarra River after both tugs had been dismissed and a few minutes later passed under the Westgate bridge at a speed of 6.6 knots when the helmsman reported that the rudder was not responding to the wheel. With its speed increasing, the ship moved further off course and tracked toward the western edge of the dredged navigable Yarra River channel striking navigation beacon 32. At the time, the ship’s speed was 7.7 knots.
The two tugs were nearby and returned, and helped control the ship’s erratic movement. The ship was then moved to Webb Dock for inspection. The ship sustained minor paint damage but the beacon was significantly damaged.
“Any loss of steering can imperil the safety of the ship, and life at sea,” said Mitchell. “Unclear or ambiguous operating instructions and terminology should be corrected as soon as they are identified.”
CMA CGM has taken measures to address the ambiguity by revising the steering guidance across its fleet. The liner’s fleetwide “steering gear failure” procedure has been amended and titled to become the “emergency steering procedure.”
Ports Victoria has also updated the harbor master’s directions for Melbourne to enhance towage requirements while transiting the Yarra River. This now includes advice for the crews of ships that experience a main engine or steering failure while transiting port waters.
Top photo by Bahnfrend of CMA CGM departing Fremantle in 2020 (CC BY-SA 4.0)
NTSB: Ineffective Voyage Planning Caused Towed Crane to Hit Mackinac Bridge
The NTSB report on a 2023 bridge strike says the captain of a tow vessel and barge company managers’ ineffective voyage planning and failure to conduct required checks caused a towed crane to strike the Mackinac Bridge in Michigan. They failed to confirm the air draft and bridge clearance, and the result was $665,000 in damages to the crane as well as $145,000 in damage to the underside of the bridge.
The towing vessel Nickelena (103 feet) was regularly employed to move barges transporting construction equipment to sites around the Great Lakes. In May 2023, they were hired to tow a barge transporting a 160-foot-long boom crane and 5-foot “rooster” sheave on a deck barge from Escanaba to a construction project at Sault Ste. Marine, Michigan. It was a standard assignment, including the fact they would have to transit under the Mackinac Bridge, a roadway suspension bridge that connects the Upper and Lower peninsulas of Michigan.
The crane was secured on the barge on May 6, and the tow commenced. After leaving the port, the captain ordered the tow line increased to 500 feet, and they proceeded. He left the bridge to rest but planned to return before 0200 when they were due to pass under the roadway bridge. The National Oceanic and Atmospheric Administration determined there was no traffic and minimal wind effect at 0200, and the NTSB reports the tow was moving at 8 knots within the marked channel.
The first contact with the bridge was with the stiffening truss below the roadway, at the top of the truss’s bottom chord (about 155 feet above the water). The report indicates given the configuration of the crane, the wires securing the crane boom would have hit first, and then when they parted, the boom would have contacted the top of the chord. As the barge continued forward, the boom would have been pushed backward, and its angle and height above the water would have increased, leading to damage higher up on the bridge. At some point, the boom contacted the upper diagonal truss, about 183 feet above the water, before folding back and collapsing on the barge.
The engineer aboard the tow vessel was on deck while there was a crewmember at the helm. They did not report hearing the contact, but said when they looked aft, they noticed they could not see the crane’s boom.
The investigation showed that the captain and the managers of the barge company did not attempt to verify bridge clearance and instead accepted the word of the managers supervising the loading of the crane, who told the captain, “Everything’s secured, ready to go.”
The NTSB determined the managers made a visual evaluation that the angle of the crane boom was between 50 and 60 degrees, and the boom was 140 feet. The Load Moment Indicator on the crane was not working, so they relied on their judgment. They decided against lowering the boom to decrease the angle because they thought it would reduce the stability of the barge.
Towing vessel operators are required to have a towing safety management system (TSMS), and voyage planning would have been part of the process. The company operating the vessel, Basic Towing, told investigators they had a TSMS, but the NTSB says no documentation was found that a navigation assessment was conducted and no attempt by the captain to verify the tow was safe for the intended route.
The water under the bridge was higher than average, with clearance at about 153 feet instead of the normal 160 feet. However, it did not matter because the analysis showed the boom was at approximately 62 degrees, which equated to a height of 162.3 feet. The report says the boom needed to be at about 55 degrees to pass under the bridge at the center of the channel. The visual evaluation also underestimated the length of the boom by 20 feet. The NTSB reports the boom was 10 feet too high for clearance.
The erroneous estimates provided by the managers set off the chain of events. However, the captain, who was responsible for ensuring the safety of the transit, did not confirm the boom height, nor was there an attempt to verify the bridge’s vertical clearance.
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