20th January 2012
Modern cruise ships: Are their designs dangerous?
By Leo Kent

How can we prevent another Costa Concordia tragedy?

There has been a media sensation surrounding the sinking of the Costa Concordia off the coast of Italy last Friday, perhaps in large part due to the chilling coincidence it happened on the 100th anniversary of the sinking of the Titanic.

As the days have progressed there have been various conflicting reports and conjecture over how this tragedy happened. We have heard a lot about the Captain, who is fast becoming the villain of the story, ignoring orders not to deviate from the planned route and fleeing the ship before others had got to safety. Certainly he has a lot to answer for. Regardless of his actions however, some people are asking how a modern day cruise ship could capsize so easily. Are there serious design flaws?

When the Titanic was built it was the biggest ship in the world at 882 Ft long and weighing 46,328 tonnes. In the 100 years that have passed ships have become even larger. Where the Concordia is only marginally longer than the Titanic at 952 ft long, it is more than double its weight at 112,000 tonnes.

The top-heavy design

If you look at two pictures of the ships there is one noticeable difference: the height. The Costa Concordia is much taller than the Titanic and this has become a modern trend in cruise ships. Much like high-rise flats, it’s a way of fitting as many people as possible into a confined area. Does this top-heavy design make the ship less stable and more liable to capsize?

The union for maritime professionals, Nautilus International, has been very vocal since the accident stating they had been warning that an accident like this was inevitable. Andrew Linington, from Nautilus, wrote in the Guardian about new cruise ship designs, “The number of decks has been increased, with additional leisure facilities, to increase revenue-earning capacity. Additional swimming pools, coupled with a number of slack tanks when in operational service, further reduce vessel stability.”

However, when we spoke to Mark Staunton-Lambert at the Royal Institute of Naval Architects, he seemed to disagree. He claims, though it appears to be top-heavy, in actuality the weight is properly spaced. He says, “It’s not really a question of how tall they are, it is a question of where their centre of gravity is and their centre of buoyancy.”

Was the top-heavy design of the Costa Concordia at fault?

Apparently, the decks above the hull are relatively light compared to the weight of the hull where the heavy engine lies and the weighted keel below. Moreover, there are regulations set in place that have to be followed regarding the weighting of a ship to ensure stability. Staunton-Lambert says that boats that didn’t pass rigid safety tests and adhere to the rules for safe design, “would be breaking regulations, simple as that. The flag state wouldn’t allow it, the classifications designers wouldn’t allow it and the owner would be at fault in even trying to think about it.”

What are the regulations?

In finding out how stringent the regulations are, we contacted the International Maritime Organisation (IMO), and a spokesperson ensured me that under the international convention for Safety of Life at Sea (SOLAS), “all ships had to be designed to ensure they can’t capsize during expected operations”. One feature of design that it insists upon is the compartmentalization of the hull.  In Chapter 2, clause 1 of SOLAS it states, “the subdivision of passenger ships into watertight compartments must be such that after assumed damage to the ship’s hull the vessel will remain afloat and stable.”

So why did the Costa Concordia not remain stable after its hull was damaged? We will have to wait for the conclusions of the investigation into the accident in due course but it seems odd that the ship, which would have to have abided by the SOLAS convention in order to sail managed to capsize. I asked Staunton-Lambert. He said, “(it depends) where and how big the hole is in the hull and so just how many watertight compartments were flooded. Make a big enough hole and you can sink any ship. There is also a possibility that the grounding of the vessel may have also contributed to the vessel heeling.”

Is it time to reassess cruise ship design?

Interestingly, the Titanic was one of the first ships to use the innovative new design of watertight compartments throughout the hull with the intention that, if two or three compartments were flooded, the ship would still not sink. When the White Star Line were informed that the Titanic was in trouble, the vice president P.A.S Franklin is quoted to have said, “we place absolute confidence in the Titanic. We believe the boat is unsinkable.” By the time he spoke these words the Titanic had sunk.

Of course, it would be foolhardy to believe that a ship could never sink. The sea is a dangerous place and man cannot control it. Having said that, a reassessment of cruise ship design is needed to make sure that another tragedy like this can be prevented in the future.

Image credits:

Vega Gonzalez / Shutterstock.com

The End
  • anon

    Just a quick comment, the Titanic sank in April, not January

    • Anonymous

      That is correct, in the early hours of Monday 15th April 1912. I was referring to 2012 generally being the centenary of the sinking.

  • http://www.ianmayman.com/ Ian

    I can’t believe this question has been asked. It is attention seeking and adds no value, for example, why is there not a list of cruise ships with design faults? This article is scaremongering. The only redeeming feature is the mention of a response from a naval architect – someone clearly more knowledgeable on the subject than the author of this post.

  • Eloi

    Ian, Let’s see, a compromised hull that immediately causes total loss of all power and ballasting control allowing a list severe enough to prevent some lifeboats from deployment and making it difficult for passengers to reach their muster areas? Doesn’t sound like an inherently stable or redundant system design to me. Sounds more like reliance on an uninterrupted single point of power placed to resolve center of buoyancy and other top heavy stability shortfalls.

    Hard to say but they may have been able to significantly extend the time to evacuate if propulsion, steering and ballast control remained available from the bridge.

    Do you really think that these questions are just fear mongering and should not be asked?

There were no articles found matching your filter