If you’ve seen the photos/video of the salvage operation you’ve seen the bank of cables and pulleys on the port side of the ship. Anyone know to what these cables are anchored?
Googling ‘parbuckling’ turned this up:
[quote]
[ul][li]A “holdback” system of chains attached to the island on one end and the hull on the other to ensure Costa Concordia rolled in place[/li][li]A man-made ledge inserted into the island face to provide a landing surface for the vessel[/li][li]A series of sponsons attached to the hull’s port side so as, when flooded, to increase the torque on the hull and to unburden the pulleys and winches[/li][li]An arrangement of cables rising from the edge of the ledge over the sponsons on the port side of the hull[/ul][/li][/quote]
Now that that’s been answered…
I have always wondered why they didn’t just fill the ship with inflatable bladders (think jumpy castles). A large number of these inflated incrementally in a controlled sequence would give buoyancy to the ship and enable it to be righted. Perhaps some structural welding would be required in places but nothing would need to be watertight.
Just my thoughts…
There are not enough large and clear spaces…
Inflatable bladders would get cut open by sharp things inside.
The intermediate floors are not designed to carry the weight, and there is no way to re-inforce.
IF lots of little bladders were used, it would take too long and the oldest bladders would be too old before it floated.
Also, it was in danger of sliding down the slope into the depths. (Why didn’t they just give it a push ? )
Another question. Where are they going to chop the thing up. All the pictures I’ve ever seen of cutting up ships is that shithole in Pakistan or India where people endure incredible danger chopping up supertankers with a cutting torch. What facility are they moving it to and is it in the Mediterranean?
Every news article says that the salvage is complete, but in my own mind, this, although the most difficult part, is only the beginning.
The Mythbusters made it work.
In Civitavecchia apparently.
Go BBC News - Salvaging the Costa Concordia for a good picture and graphic.
And here - Costa Concordia: Stricken ship set upright in Italy - BBC News
It looks as if the final destination has not yet been decided, but almost certainly it will be in Italy, in Spring next year. No way are they going to risk towing it across the Indian Ocean.
I believe they are going to a port in Sicily, where they will remove passenger belongings and send them back to the passengers, remove any still-usable items on the ship, and safely dispose of the waste (2 weeks worth of rotted food for 4,000 people, the sewage from those people, cooking oil, engine oil/lubricants, any remaining fue; (most was pumped out soon after the wreck), etc.
After all that, the shell of the boat will be chopped up for scrap. I don’t know if they will do that there or not. In Pakistan or India they can hire people to do this very cheaply and without the expense of safety or environmental regulations, but the cost (and risk) of towing it there would be considerable. I think most ships scrapped there were still able to get there under their own power.
I am not buying that.
I would have thought that a team of divers/welders could cut off the worst offending bits of jagged steel. Weld some plate steel over gaping holes.
The big manufacturing job would be to construct the bladders. But if they were constructed to the size of the rooms and oriented so that they inflated properly. Bladders on exterior walls might need to be reinforced with kevlar or something. It might be expected that some would fail but that should not affect the overall plan too much.
Divers install the (admittedly hundreds) of bladders. They may need to be inflated with water so that they fill their space properly. Long bladders fill hallways.
When all is ready, air is pumped in displacing the water. There will need to be some clever sequencing to ensure that the change in the ship’s overall weight distribution is controlled as it gains buoyancy. You also wouldn’t want too much in the way of unequal forces on internal structures. The hull itself will be able to cope with the pressure differential – that is what it is for.
As for sliding down the slope… With the bladders you have control over the level of flotation. You can stop it from sinking.
Sure it would be an engineering challenge, But I can’t help thinking it would be easier and cheaper than building the superstructure that has been built.
It would also take a helluva long time to design, make and install them (plus very dangerous as it means moving around inside the wreck).
The above-linked BBC article suggests Sicily:
Might have been speculation on behalf of a journalist as it’s the closest port.
I am not an Engineer, but this is one issue I can see that wouldn’t work. If at any point during the operation the ship starts sliding, by definition the ship isn’t at positive buoyancy since it would already be floating. So once it starts sliding you have to rapidly inflate all your bags which doesn’t sound like it would be very gentle on the ship.
Well, the airbags probably don’t exist in the massive quantities they need. But chains and cranes and cables and anchors and all that stuff – it’s just lying around shipyards waiting to be used. And when you’re done, you still have a use for all those chains and cables, while all your custom inflatable bladders would be just so much PVC going to waste.
An additional complicating factor is that the ship was effectively lying on those areas you’d need access to in order to insert your bladders. I dunno how happy salvage divers would be, having to execute a reverse Poseidon Adventure while dragging bouncy castles through corridors of twisted metal.
Although the up side of the ship looked ok, the rest of it is a bit of a wreck.
The ship had 1500 cabins.
Also, a ship is an enormous thing. Structurally, it barely holds together when supported by the full length of the hull. You can’t just pick it up using only the internal structures. It would be like trying to pick up a skyscraper by the roof.
A couple of problems come to mind.
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The ship ran aground. Which means even when it was intact, it didn’t have enough buoyancy to clear some rocks. Even if you fill the entire ship with air bladders (without any gap left for seawater to remain), the best it can do is bring it back to that original (insufficient) buoyancy.
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Each air bladder will push against the ceiling and wall of the compartment it’s put in. These are mostly flimsy panels supported by weak internal structures. Especially the upper floors.
Just wanted to speak to the scrappign operation:
I recall a “modern marvels” episode that showed an American scrapyard for large stuff (like airplanes and ship modules). They use cranes and power-arm (think backhoe) with a giant jaws-of-life-type hydraulic cutter on the end to cut the modules down into chunks small enough to fit in their oversized compactor or hammer mill.
Huge stuff like this requires some heavy duty infrastructure (cranes, a drydock or shipyard, etc.) to break it down into modules that can then be shipped off to smaller scrapping facilities. And the modules, I’m referring to are the huge sub-assemblies like the forward superstructure, the propulsion deck, the bow, and the like. The largest chunks that get sent to the shipyard, rather than assembled onsite.
Have you seen videos of those Indian scrapping sites? They just beach the ship. Hordes of workers start tearing it apart. People actually use hand tools like hammers to break up pieces.
You don’t need high tech if you have thousands of very hungry people. (Something that is severely lacking in the immediate vicinity.)
Maybe they could order the ship’s captain to do the breakup by himself by hand. Seems like a suitable punishment.