Hundreds, probably even thousands of containers are lost at sea every year creating UFO’s – Unidentified F***ing Objects (that’s ‘Floating’ of course) – as Dick Durham investigates…

It would take just 135 Very Large Container Ships (VLCS) moored end to end to run the length of New York’s 13-mile Manhattan Island and yet there are more than 6,000 of them and over 80,000 of their smaller sisters traversing the oceans of the globe annually. Together they are responsible for transporting more than 80 per cent of the world’s goods, a business worth four trillion US dollars a year.

These giant ships, with their sky-scraper stacks, actually look like lengths of Manhattan chopped up and sent to sea but, under a well-recognised set of heavy weather conditions, they can become unstable. And yet these ships are set to get even bigger.

Although container ships are exceptionally wide at deck level, the biggest being over 60m in beam (in order to carry the maximum number of containers) they are also cut away at the bow with flared topsides, and at the stern have giant overhangs, making the wetted surface of the hulls more easily driven, thereby saving on fuel costs, but also, unfortunately, making them less stable.

As a result of such economies of scale these mammoth ‘box’ ships, as they are known in the industry, can be susceptible to a phenomenon called ‘parametric rolling’. This happens when a storm sets in producing a wave length longer than the ship. The ship’s scalloped bow pitches as its beamier back end starts to roll, this sets up a twisting motion which, in turn, amplifies the ship’s rolling, sometimes in excess of 30 degrees, putting severe stress on the twist-lock systems holding the tottering stacks of boxes in place. Then, like some berserk metronome, the stacks take on an uncontrollable life of their own and in some cases, the lashing/locking systems fail and the boxes are thrown overboard in their hundreds. We understand some container locking systems are actually rigged so that they can be deliberately jettisoned if the captain considers the ship to be in jeopardy.  

James Baker, containers editor for Lloyd’s List told Ocean Sailor: ‘Some hull designs, with flared bows and flat sterns, appear to be susceptible to parametric rolling in otherwise benign conditions. If you take a ship that lends itself to 30-degree rhythmic rolling, pushing on through some bad weather with poorly lashed stacks that have 30-tonnes of cargo sitting at the top of the stack…. it’s a recipe for disaster’.

The latest major casualty was the 364m One Apus box ship which lost 1,816 containers, including 40 loaded with dangerous goods such as fireworks, batteries and liquid ethanol. She was 1,600 miles north-west of Hawaii while on passage from Yatian, China to Long Beach, California on November 30th 2020. Reports claimed the swell had made her ‘roll heavily’. After losing the boxes, she had to turn back and dock in Kobe, Japan, where, as we went to press, further damaged containers were being removed. One of the theories accident investigators are exploring is whether she suffered from an ‘accelerated roll’ ie parametric rolling.

The Society of Naval Architects and Marine Engineers, based in Washington DC, have investigated parametric rolling and found box ships’ stability decreases on the crest of a wave and increases in the trough. ‘The large change in stability was found to be due to hull form; massive bow flare and stern overhangs caused a “dramatic” difference in waterline form’. Their findings threw up recommendations which included fitting ships with anti-roll fins and rudders, and containers with sensors to monitor roll effects.

Nick Savvides, managing editor of Container News told Ocean Sailor: ‘Parametric rolling is an ongoing problem for the container shipping industry and is often the cause of cargo loss. Longer ships are also now much wider and carry more containers that are in turn stacked higher. The effect of their shape, size and cargo distribution means they are often actually more susceptible to parametric rolling than smaller ships because, in certain sea conditions that aren’t necessarily extreme heavy weather, the bow tries to roll at a different time to the stern causing dangerous twisting. With very high container stacks, the forces exerted on the container lashing system and the containers themselves, can lead to ‘stack collapse’ with dreadful consequences for a ship in heavy weather.

Increased climate temperatures are also playing their part in container loss according to ONE’s CEO, Jeremy Nixon: ‘Global warming is happening…typhoons are tracking further north through the shipping lanes in Asia and they are impacting more on ports, too’.

Marin, the Dutch Nautical Research Institute, reported that ‘green water impacts’ from giant waves, can push over ‘complete stacks of containers like dominoes.’ The institute’s findings from scale models and tank tests showed that ‘ship vibrations from heavy seas can damage container lashings’.

Their investigators were looking into the ULCS Zoe owned by Mediterranean Shipping Company which lost 342 containers off the Dutch Frisian Islands when she was caught in a north-westerly storm in January 2019. The containers polluted part of the Wadden Zee, a UNESCO World Heritage site.

Following a further loss of seven containers from the Orient Overseas Container Line’s Rauma in the same sea area in February 2020, the Dutch Coastguard announced they would close sea routes in certain weather conditions and offer re-routing advice to container ship captains. 


Stop Press

As we went to press the box ship Maersk Essen has just reported losing 750 containers in the North Pacific while on passage from Xiamen, China to Los Angeles in heavy weather.

A drop in the ocean

So how many containers are lost each year, and what sort of threat do they pose to ocean sailors? When I investigated this issue 20 years ago for Yachting Monthly, figures were hard to come by. In 1994 single-handed yachtsman Josh Hall had been told by the Cape Town harbour master that 40,000 containers had been lost overboard from the decks of Atlantic box ships in recent years. Back then box ships carried a maximum of 5,000 containers, now they carry the equivalent of over 23,000 TEU. This is the abbreviation used to describe 20ft container units as ships carry both 20ft and 40ft containers.

The biggest ULCS in the world, Hyundai Merchant Marine’s Algeciras, is, at 400m LOA, longer than the City of London’s Shard building is tall. She made her maiden voyage to London’s new Thames Gateway port last summer with fire hose tugs celebrating her arrival with giants sprays of water. This ship is known as a Megamax container vessel, the latest category up from the Panamax, Post-Panamax, New Panamax and Malaccamax classes.

Traditional seafarers might think these great box ships would be better defined as the Madmax class, and yet, according to the World Shipping Council ‘only’ an average of 1,382 containers are lost at sea annually, although this figure is thought to be as high as 10,000 a year, according to unofficial sources, say Marin. The WSC – not an independent body – concedes that ‘catastrophic’ events will boost the figures.

No one is suggesting shipping companies are trying to hide their box losses, but nevertheless, in case they are tempted, the International Maritime Organisation, the UN body concerned with ship safety, told Ocean Sailor that in May this year (2021) their Maritime Safety Council will meet to discuss the mandatory fitting of a ‘mechanism which will automatically declare the loss of containers at sea’.

The IMO also produce guidelines on the ‘stuffing’(loading) of boxes making sure heavier goods are loaded lower down and that dangerous goods are loaded in boxes nearest the doors. They also publish advice on how to manoeuvre the ship in heavy weather conditions.

Ill-fitted, corroded, or slack turnbuckles (box lashings) have also been found by investigators to have been a factor in past accidents and container losses.

Some recent container losses

March 2006 – Hyundai Fortune lost ‘dozens’ of boxes ‘blown overboard in an explosion’ off the Gulf of Aden.

January 2007 – MSC Napoli hull cracked open in heavy seas and beached at Lyme Regis, Devon. Container goods raided by beachcombers.

March 2011 – Maersk Honam containers lost from bow section in a fire in the Arabian Sea. Five crew killed.

October 2011 – Rena struck a reef in the Bay of Plenty, New Zealand. ‘Substantial’ number of boxes lost.

June 2013 – MOL Comfort lost 4,293 boxes when she sank in Indian Ocean

February 2014 – Svendborg Maersk lost 517 boxes in the Bay of Biscay in rough weather.

October 2015 – El Faro sank in a hurricane off the Bahamas losing 33 crew and 391 boxes.

January 2018 – CMA CGM G rolled unexpectedly in ‘very heavy seas’ 20 degrees to starboard then 20 degrees to port causing box stack to collapse. 137 containers went overboard. 

March 2018 – Maersk Shanghai lost 76 boxes in high winds and heavy seas off North Carolina.

May 2018 – YM Efficiency lost 80 boxes in heavy weather off SE Australia.

January 2019 – MSC Zoe lost 342 boxes in a storm off north Holland. 

March 2019 – One Helsinki Bridge lost three boxes off Boston.

February 2020 – Rauma lost seven boxes off north Holland.

May 2020 – APL England lost 50 boxes in heavy seas off Sydney, Australia.

June 2020 – Barge under tow lost 21 boxes in a storm on passage from Honolulu to Hilo. 

June 2020 – Navious Unite lost three boxes in rough seas off SW Australia.

November 2020 – One Aquila lost 100 boxes in rough seas on passage to Long Island.

November 2020 – One Apus lost 1,800 boxes in Pacific in rough weather.

January 2021 – Evergreen Marine MV Ever Liberal lost 36 boxes off Kyushu, Japan in strong winds.

The boxes are made from a special type of steel called Corten steel, which was developed to resist weathering, so they will last in the water for much longer than you might imagine. They carry virtually every commodity know to man from chemicals, wine and vegetable oil to logs, machine parts and fireworks.

Most containers sink but some float for days, months, or even years. Reefers (refrigerated boxes) float for longer because of their buoyant insulation.

US oceanographer Dr Curtis Ebbesmeyer tracks global flotsam and reports it on his website Beachcomber Alert. His investigations revealed one container loaded with 10,000 computer monitors floated around the Pacific for a year before coming ashore on the Queen Charlotte Islands off British Columbia.

According to the Sail World website: ‘One Swiss marine biologist estimates there are 12,000 boxes floating around the world’s seas. This number is alarming because these large UFOs (Unidentified Floating Objects) pose a significant risk to smaller ocean-going vessels such as yachts and fishing boats. The danger of collision is actually quite high since sailors often only see boxes at the very last minute because often they barely break the surface. There are regular reports of collisions and stricken yachts have to be salvaged. In the most serious cases the boats end up sinking’.

Yachts damaged by containers

Sadly, we just don’t know how many yachts are lost due to collision with these steel icebergs because its highly likely that the yacht will be a total loss, with no one surviving to recount what happened. The list below is just a few that we do know about.

2016 – Vendee Globe yacht, Le Souffle de Nord, sailed by Thomas Ruyant hit what he believed was a container off New Zealand’s South Island.

2006 – 42ft yacht Moquini was found floating upside down 500 miles off the SW coast of South Africa. Yacht designer Alex Simonis blamed a container for the sinking. She’d lost her keel and six crew were missing presumed drowned.

2003 – Offshore 33 pilot-house ketch, Lycaena, sank after hitting an object – possibly a container – 20 miles south of St Catherine’s Point, Isle of Wight. Crewman Martin Taylor, 50, said she was under power making six knots when she ‘stopped dead, slewed over and lay on top of this thing, whatever it was’.

2001 – 130ft superyacht Silver Cloud damaged her stern gear on what was believed to be a container floating in the English Channel. She limped into Southampton for repair.

2000 – During the Vendée Globe, Ellen MacArthur’s Kingfisher was thought to have hit a container north of the equator sailing at 10 knots. ‘All of a sudden we ground to a halt with a gut-wrenching noise of ripping carbon,’ Ellen said. ‘As I leapt on deck, I saw half a daggerboard and the tip of the rudder drifting away. There were signs of rust in the water. I cannot say for sure that it was a container, but it was the most likely thing to be submerged and give that kind of unforgiving impact’.

Two UK Yachtmaster candidates died when their Farr 38, Rising Farrster, capsized on passage to Sydney, Australia. Nathan Lawrence of Cowes-based Leisure Management International, which ran the course, said: ‘That the yacht hit a container is a possibility. It is a well-travelled route and there is a lot of debris there’.

1999 – Sir Robin Knox-Johnston saw several containers awash while competing in the Clipper Race. ‘These things are a bloody menace,’ Sir Robin said. He reportedly hit a container and was holed while sailing Enza, the giant catamaran in the 1993 Jules Verne Challenge.

1994 – During the BOC Challenge Round the World Race, yachtsman Josh Hall’s Open 60 Gartmore sank off Brazil after striking what he thought was the corner of a container. ‘It was the most horrendous landing you could imagine. The boat reared up and then there was the most incredible rending sound as the bow came down. It was almost as if we’d run aground’. He was rescued by a fellow competitor.

1988 – OSTAR single handed transatlantic race from Plymouth to Newport, USA. Dutch competitor Roel Engels’ 34ft yacht Doortje hit a container in mid-Atlantic and sank. The Dutch sailor was rescued by a fishing boat.

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