Why do containership stacks collapse, and who is liable when they do?


The collapse of on-deck container stacks represents a grave threat to crew, ship safety and the environment. The shipping community and its insurers have suffered substantial financial losses during recent years as the number of collapse cases resulting in the loss of containers at sea has increased both in terms of frequency and severity.

Causes of collapse
Understanding causation is key in preventing incidents and also determining liability in individual cases.

Heavy weather has been one of the fundamental challenges for carriers since the dawn of shipping. Advanced technology for voyage planning and weather routing helps the master, but his judgment will be questioned if an incident occurs. Containers, the securing mechanisms and container stacks are exposed to great forces when containerships move in heavy weather. Parametric- and synchronous-roll resonance phenomena have caused several serious accidents involving containerships.

Parametric rolling describes large spontaneous rolling motions occurring in head or stern seas. It involves the dynamics of the length of ship and waves, as well as the vessel’s wave encounter period. A vessel’s roll angle can increase from comfortable rolling motions to over 30 degrees in only a few cycles, causing excessive acceleration on the container stacks. Synchronous rolling is caused by the ship’s rolling period becoming synchronous with the wave period. The waves may then cause resonance, meaning that the ship may lose control over the roll angles as the action of the wave rolls the vessel increasingly over.

Size matters, as bigger vessels move differently in the sea compared with smaller vessels. For example, investigations following the APL China incident in 1998 revealed that large boxships with large bow flares are particularly exposed to parametric rolling. Furthermore, the containers on board the largest container vessels are stowed up to 130 feet above the waterline and nearly 200 feet wide across the deck. When ships and container stacks of these dimensions start rolling, you do not have to be a physicist to understand that the stacks will be subject to great forces once the vessel starts to move with the motions of the sea.

Ship stowage is an important factor because weight distribution on board also influences the vessel’s motions at sea. The metacentric height (GM) is a measurement of the initial static stability of the vessel. It is of the utmost importance to get the GM within the right range before the voyage. This represents challenges in terms of correct cargo planning both ashore and on board. In practice, advanced software will do most of the job, but computer programs depend on correct software development and correct data entered, as well as human interaction and, ultimately, human decisions.

The GM is calculated as the distance between the center of gravity of a ship and its metacenter. The metacentric height influences the natural period of rolling of a hull. A low GM will cause the vessel to roll excessively with movements that are too large. A high GM implies greater initial stability against overturning, but high GM is also associated with shorter periods of roll, which will cause rapid movements and greater forces on the cargo stowage. Hence, the GM has to be correct — not too high, not too low.

Cargo stowage inside containers causes problems, as a container stack is only as strong as its weakest container. If cargo inside one container starts to shift, it may have a domino effect on the stack. We have seen severe cases where one piece of cargo has damaged its container structure, resulting in the collapse of a complete row of containers. Therefore, the container securing manual (CSM) must be followed accurately, and further stowage guidelines should be sought for problematic cargoes. One of the challenges is that container carriers largely depend on shippers, freight forwarders or their subcontractors to pack and secure cargoes adequately. Errors are inevitable.

The container is designed to fit the purpose of containing cargo, but if exposed to extreme weight pressure from excessive loads, containers may suffer structural failure. Container shells are exposed to wear and tear, rough handling and operations that may weaken their structure. If one container fails, the rest of the stow above and around will follow.

The weight of cargo is declared by the shippers. Misdeclaration of weight is an industry problem and may cause considerable difficulty for cargo stowage planners as they rely on cargo details as declared by the shippers. If numbers are inaccurate, or even deliberately misdeclared, the integrity of container stacks may be jeopardized.

APL England lost about 50 containers overboard and nearly 80 others were damaged after the ship experienced a temporary loss of propulsion in heavy seas off Sydney, Australia, on May 24. The Australian Maritime Safety Authority detained the ship, and the captain was charged with offenses related to pollution and damage to the environment.

Australian Maritime Safety Authority photo

Lashing and securing of thousands of containers in large stacks on board is a major challenge. Failure to do it correctly may have serious consequences. In simple terms, containers on deck are attached to each other with twist locks in the four corners of the container. Further, lashing rods are attached between the container stack and lashing bridges or hatch covers. Each twist lock and lashing rod needs to be in the right place, work correctly, and be able to withstand required forces. Inadequate securing, missing or failing twist locks, and lashings that become loose are probably among the more common causes of containers being lost at sea. Failures in securing have caused severe incidents.

Multiple causes often make cases complex, especially when working with liability. In most cases, there are elements of several of the aforementioned causes that lead lawyers deep into legal considerations about issues such as proximate causes, intervening causes, independent sufficient causes and foreseeability.

Typical legal considerations
Assuming that causation is established, the next step is applying the law to the particular facts. We will now look at some of the reoccurring legal issues for cargo claims and charter party claims, with a focus on seaworthiness. 

Containerized cargo is usually shipped on the container shipping lines’ standard terms of carriage, which usually incorporates the Hague-Visby Rules. Whether or not the contractual carrier of cargo is liable for damage or loss of cargo will be determined by whether the carrier is in breach of its duties under the convention, or whether the damage occurred as a result of perils for which the carrier is exempt from liability.

The carrier’s fundamental duty: properly care for the cargo

Under the Hague-Visby Rules, the carrier shall “properly and carefully load, handle, stow, carry, keep, care for and discharge the goods carried.” This requires the carrier to adopt a solid system to fulfill its obligation throughout the time the cargo is in the carrier’s custody. For instance, if lashings of container stacks appear to come loose during the voyage, the carrier is under an obligation to correct the problem and tighten the lashings. This is a contractual obligation, meaning that the contractual carrier is contractually bound even if he is not the actual carrier and in direct control of crew on board. Generally, the carrier is not obliged to improve stowage inside the container. This responsibility will normally lie on the shipper’s side. 

When cargo is shipped in apparent good order and condition but is discharged damaged, the carrier bears the burden of proving either that the damage occurred without fault, or that it was caused by an “excepted peril” within the Hague-Visby Rules.

Error in management of the ship

The Hague-Visby Rules state that “neither the carrier nor the ship shall be responsible for loss or damage arising out of … act, neglect or default of the master, mariner, pilot or the servants of the carrier in the navigation or in the management of the ship.” 

It might be possible for carriers to rely on negligent navigation as an excepted peril if it can be proven that there was, for example, a lack of good seamanship in deciding to sail in severe weather conditions. Also, failure to take the action necessary to prevent excessive rolling may be considered failure to properly navigate and therefore exempt the carrier from liability.

“Management of the ship” does not include management related to the cargo under English law. This principle was set out in the Gosse Millerd case (Gosse Millerd v. Canadian Government Merchant Marine, 1927): “If the cause of the damage is solely, or even primarily, a neglect to take reasonable care of the cargo, the ship is liable; but if the cause of the damage is a neglect to take reasonable care of the ship, or some part of it, as distinct from the cargo, the ship is relieved from liability.” This means that if a container stack collapse is solely caused by error in cargo stowage, there is no exemption from liability for the carrier based on the Hague-Visby Rules.

Containers dangle from APL England in May after the boxship was able to restore propulsion and head for the Port of Brisbane, Australia. Cargo on the largest containerships can be stowed up to 130 feet above the waterline and nearly 200 feet wide on the deck.

Australian Maritime Safety Authority photo

Perils of the sea

The Hague-Visby Rules state, “Neither the carrier nor the ship shall be responsible for loss or damage arising out of … perils, dangers and accidents of the sea or other navigable waters.” In Scrutton on Charterparties and Bills of Lading, 20th Edition, Justice Thomas Edward Scrutton defined such perils to include those “peculiar to the sea or to a ship at sea, which could not be foreseen and guarded against by the shipowner or his servants as necessary or probable incidents of the adventure.” Hence, the starting point under English law is that such a peril must be “of the sea” in the sense that the loss must be attributed to natural causes.

The criteria “could not be foreseen” means that the peril must be beyond what is reasonably foreseeable and could be avoided by the carrier. This has naturally made the “perils of the sea” defense increasingly more difficult for carriers as technology has developed. For general weather conditions throughout the voyage, carriers usually will be expected to have the necessary equipment to avoid the peril. However, the defense remains possible. For example, unusually high or challenging waves may be considered unforeseeable and exempt the carrier from liability. Experts have debated whether parametric rolling or resonance, which can occur in even moderate weather conditions, is foreseeable. The legal landscape is yet to be completely clarified.

No fault or privity of the carrier

The Hague-Visby Rules exempt the carrier from liability for damage occurring “without the actual fault or privity of the carrier, or without the actual fault or neglect of the agents or servants of the carrier.” This is usually referred to as the “catch-all exception” and, crucially, carriers can rely on this exception if they are able to prove that there was no fault on their part. In container-stack collapse cases, the carrier may typically argue there is no fault on their part if the fundamental duties to care for the cargo are fulfilled, and thereby refute liability under the contract of carriage. The “non-fault” exception is extended to fault by the carriers’ servants.

Charter party claims and seaworthiness

Ultimate liability for damages arising out of a container-stack collapse case often will end up as a discussion regarding seaworthiness between contractual carriers of cargo and the actual carrier (the shipowner) under charter party contracts. 

The classic definition of seaworthiness is that “the ship must have the degree of fitness which an ordinary careful owner would require his vessel to have at the commencement of her voyage, having regard to all the probable circumstances of it.” A question that often arises in container-stack collapse cases is to what extent the ship and equipment was sound and correctly applied upon departure, and whether it was fit to withstand the ordinary perils of the sea. Hence, seaworthiness will be considered in context with what the owner could reasonably foresee in terms of occurring sea perils. 

For instance, inadequacies with regard to the vessel’s lashing and securing equipment in a stack collapse case could be enough to render the vessel unseaworthy. Furthermore, if there is an excessive top-heavy stow on departure that compromises the stability of the container stack itself, the vessel arguably may be in unseaworthy condition due to the error in stowage.

In addition to cargo claims and the legal implications under bills of lading, liability for environmental damage has been high on the agenda in connection with severe incidents in recent years. When containers and cargo drift in the ocean or end up on shorelines, authorities usually will turn to the “waste producer,” which is generally considered to be the shipowner or operator of the vessel. The waste should be, and will be, removed. The ultimate liability for the costs and losses often will end up in dispute under charter parties.

To conclude, the law often applied in stack collapse cases is over 100 years old and made to fit, sometimes uncomfortably, with modern ships and technologies. Regrettably, container-stack collapse cases have serious consequences involving monetary losses, ship safety and environmental impact. We fear carriers, insurers, lawyers, judges and arbitrators will continue to be challenged by the complexity of stack collapse cases for years to come.

Are Solum is a senior claims executive and lawyer for Gard (www.gard.no), a protection and indemnity (P&I) insurer based in Arendal, Norway.

By Professional Mariner Staff