After lying on its side for 20 months, Costa Concordia finally back upright on Tuesday, September 17, 2013. The engineers managed to uphold the 114 tons weighed ship was in the rescue operation for 19 hours with a technique called parbuckling. "The ship is now standing upright. Process is much better than what many people predicted," said Nick Sloane, expert rescue vessel that involved in the operation. "When it starts to move, the ship was moving slowly but surely. Absolutely not twisted, just like what was planned."
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| The Costa Concordia wreckage. (Picture from: http://www.physicscentral.com/) |
Generally, the ship that ran aground detonated or dismantled at the site directly. It was much cheaper than using parbuckling techniques that cost U.S. $400 million. The project involves 500 crew from 26 countries. But the Costa Concordia ran aground just above the coral reef marine park and protected. In addition to containing hazardous substances, there are two bodies believed still trapped inside the sunken cruise ship near the island of Giglio, Italy, after striking the reef in January, 2012.
If there are errors in the rescue operation, the vessel can rupture and cause toxic contents spilled into the sea. Among the thousands of liters of lubricating oil, insecticides, paint, glue, and paint thinners, there are 10 oxygen tanks and 3,929 liters of carbon dioxide. Also stored at ship's refrigerator was 1,268 kg of chicken, 8,200 kg of beef, 2,460 kg of cheese, and 6,850 liters of ice cream that had rotted. Though expensive, parbuckling technique selected to lift the Costa Concordia. Parbuckling actually been used for centuries to lift or lower the cylinder-shaped objects, such as barrels or logs.
In that technique made ramp or bridge that connects two different locations heights, as well as tying down objects and rolling up the ramp. This technique is much easier than lifting heavy objects vertically. This technique is commonly used to lift logs onto trucks. However parbuckling also been used to save large ships since 1943, when the USS Oklahoma which weighs 35 tons sank in Pearl Harbor.
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| Parbuckling was used during the salvage of the USS Oklahoma during WWII. (Picture from: http://www.physicscentral.com/) |
Costa Concordia parbuckling project to begin in May 2013. Process that has never done this before, because it combines the two techniques, namely parbuckling and re-float the ship. In addition to using giant winches, the project is using chains, cables, and steel tanks.
Although parbuckling has long been used , it does not mean the project is not at risk. In contrast to the log, the ship is not cylindrical, so that this technique is more aimed at turning the ship back into the correct position rather than rolling the wreckage on the ramp.
Costa Concordia rescue on Tuesday consisted of efforts to rotate the ship, so that it stands upright on the under water buffer ramp and can be pulled to shore. Initially shipwreck lying on its right side, at an angle of 65 degrees from the vertical axis. The engineers must play at least about 40 degrees before they can take advantage of gravity to enforce ship.
Parbuckling actually very risky because the diagonal must exert a force on the ship. If the ship shifted to the side, instead of rotating, it is impossible to return the vessel to a position where the ship could tilt up to vertical.
Water depth also has great impacts on the technical work around the ship. According to Simon Boxall from the National Oceanography Centre, an additional 10 meters deep the course could make Parbuckling Project will not produce results.
Costa Concordia rescue project has a much larger scale than previously the vessel lifting that used parbuckling technique. The ship has a length of nearly 300 meters and weighs more than 114 thousand tons. The ship was also filled with water and bilge large tear on one side, so that part of the structure must be strengthened. So that the ship was not destroyed then the forces that are deployed should be completely balanced during parbuckling process. Ship owners plan to withdraw the ship was to be stripped. Material that can still be saved is estimated around 30 thousand tons.
"It's a perfect operation," said Franco Porcellacchia, technical team head of Crochiere Costa cruise company, which is owned by Carnival Cruises, an American firm. Vessel lifting efforts began on Monday, September 16, 2013 at 9 am. At midnight, the ship successfully pulled off of the reef and began to stand with a slope of 25 degrees, even though that was delayed because of the storm. The condition of the ship was safe enough for rescue crews to begin putting water into the caissons (giant steel boxes) are welded to the hull facing upwards. They use water's weight to complete the overthrow of the ship onto the steel frame ramp that built on the sea floor.
"Four hours later, the Costa Concordia had been standing on the ramp," said Franco Gabrielli, head of Italian Civil Protection Authority. Once the ship back upright, visible diagonal line separating the white paint of the hull is lifted with mud-brown on the starboard side.
On Tuesday, 65 percent of the ship is still under water, in the middle of the sea-park and a protected coral reef. The next stage is to install the floating structure on the Costa Concordia and pumping water out. When this stage is completed, the hull under water only as deep as 18 meters. It is estimated the ship could be withdrawn next year.
Costa Concordia rescue operation is expected to be the costliest marine debris removal projects ever made, the total cost would be around U.S. $800 million and insurance losses of more than U.S. $1.1 billion. *** [EKA | FROM VARIOUS SOURCES | REUTERS | CNN | PHYSICS CENTRAL | TJANDRA DEWI | KORAN TEMPO 4348]
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