Why The Concordia Flipped

This entry was posted by Thursday, 19 January, 2012
Read the rest of this entry »



You know the Costa Concordia? The gorgeous cruise ship that sunk off the coast of Giglio?

Normally (when it’s not turned over on its side) 26 feet of the ship is underwater. The rest sticks straight up for thirteen stories.

Top heavy, right?  No WONDER it flopped over!

Modern cruise ships are very high tech. The architecture says “Physics be damned! I look impossible because I AM impossible!” So is this a bad way to design a ship? Did top marine architects not notice that their leviathans aren’t stable in the water? Did the insurance companies insure half billion dollar sinkers because they were foolish? Were the insurance agents too busy to drive out to the dock and actually take a look at the the mess they were insuring?

To answer these oh-so-great questions, MISTER ScienceAintSoBad, did a little research. An article  in the New Scientist by Paul Marks helped. These “ships of the future” are “engineering intense”. In spite of their Towering Inferno look, they’ve got plenty of “ballast” down below – enough to pass tough, tough stability tests where the ship is pulled from vertical with weights and released. It’s part of routine shipyard testing and it’s a tough exam. The ship has to recover from a vicious lean and right itself  fast enough or nobody’s going anywhere.  There are watertight compartments too which are designed for water ballast to be pumped around. This is to provide stability and compensate for forces that might tip the ship. And the lifeboats aren’t old days, either. They’re self-righting covered pods. If you can get yours down to the heaving seas, you can sail twice around the world. Guaranteed.

Engineering marvels.

But here’s the thing. With science we like to test our theories. We like evidence.

What’s the evidence that the Costa Concordia was a safe ship? Did it fail safe? You’re thinking “no”, aren’t you? And you’re saying this because it was over on its side and would have sunk if it hadn’t had the good luck/bad luck to have found itself a rock!

Okay. Maybe NOT so accident resistant. I’ll give you that one.

These ships aren’t perfect. Their huge profiles can make them hard to handle in strong winds. And they’re “tender”. If they turn  too fast, bad things happen. They roll like crazy. The steering limit system is supposed to prevent this. You can’t turn too sharply if your life depends on it. (I realize that it does. Thank you for that comment.)

For the moment, most of the attention seems to be on the way the crew handled things and that makes sense. But that ship’s going to get a good look over too. Maybe 13 stories is one too many.



– – – – – –

Thanks to Robert Lender for the photo: Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

Leave a Reply