Wrong Container Weights Led to Stack Collapse on U.S.-Flagged Boxship
The Verified Gross Mass (VGM) regulation that took effect in 2016 was supposed to cut down significantly on the risk of misdeclared weights in container shipping, which can cause stack collapses and dangerous stability issues. A recent incident involving a U.S.-flagged boxship shows the potential hazards that still exist if incorrect weights are entered in booking systems and if containers aren't reweighed before loading.
In early 2024, a booking agent for cargo departing California was preparing a reservation of 40 container slots for the February 3 sailing of the U.S.-flagged boxship President Eisenhower. One of the containers was flagged as overweight, so the agent split the booking into one heavy container and 39 other containers. The weight info for the new entry for 39 containers didn't automatically populate, so the agent typed in the cargo weight for all 39 boxes - as 2.5 tonnes. When including the weight of the empty container, this yielded a total loaded weight of about six tonnes for each container, and this number was recorded in the booking system. In actuality, the real total VGM reported by the shipper on the bill of lading was between 25-29 tonnes, nearly five times as heavy as what the agent put into the booking system.
On February 2, 2024, these containers were loaded aboard President Eisenhower at the Port of LA's Fenix Marine Services terminal. The majority of the boxes were stowed in the upper tiers of bay 42 on the port and starboard side, a few bays forward of the deckhouse. They were not reweighed at the terminal, nor did the STS cranes at the pier have the ability to weigh in motion during loading. The Eisenhower's chief mate performed stability calculations and draft measurements with the (incorrect) loading information supplied, and passed all routine presail checks. Early the next day, Eisenhower got under way for Oakland.
On the morning February 6, Eisenhower arrived off Oakland and shut down the main engine to drift while awaiting a berth. Wind and sea conditions gradually increased through the day, rising to 20-knot winds and 12-foot swells. The boxship was rolling up to 18 degrees in these conditions.
At about 2130 hours, the AB on duty saw "smoke" in the air on the port side. The third mate sent the AB forward to check on the cargo, and the AB found that a stack of containers was missing from the port side of bay 42. The smoke was suspended powder from collapsed containers: a total of 23 had gone over the side, and another 10 were damaged. The collapse caused an estimated $630,000 in cargo damage and $105,000 in damage to the vessel; luckily no one was hurt.
Later analyses by the ship operator found that the improper loading configuration with the heavier-than-declared boxes would have produced excessive forces, large enough to break the lashings in bay 42. "The vessel would not have sailed with that configuration, had it been known," the company told NTSB.
The booking agent has changed its computer system to automatically capture the VGM from the shipper's original booking, and it now requires individual verification of all VGMs under 10 tonnes.