One week ago, the Costa Concordia grounded off the island of Giglio. Eleven passengers or crew are confirmed dead. Twenty four people are missing. The ship itself has sunk in shallow water having rolled 80 degrees on its side. What else do we know? Several basic questions remain unanswered.
Where precisely did the Costa Concordia run aground and on what? No one really knows. From the charts there do not seem to be any hazards where the first grounding is supposed to have taken place. The captain steered the ship into shallower water where she currently lies. From Lloyd’s List:
The vessel overturned in the area covered by UKHO’s chart GB1999. But an examination of the chart, which is on a scale of 1:300,000, indicates an area of deep water.
UKHO charts have come in for flak from some parts of the shipping industry. Many of them are of Victorian vintage, compiled with the use of leadweights on lines.
Former master mariner William Todd, now managing director of one of Britain’s largest retailers of the maps, said: “If he was going between Giglio and the mainland, there are no rocks whatsoever shown in between.”
There is a 150 foot long rip in the hull on the port side of the ship with a large piece of stone still embedded in the hull. From the position of the damage on side of the hull, it appears that the ship may have scraped along an underwater ledge rather than hitting an underwater pinnacle of rock which would have damaged the bottom of the ship. There are underwater ledges in the vicinity of the small island of Le Scole off the south-eastern of the island of Giglio. This would put the grounding just slightly to the south of the assumed position of the grounding in the AIS plot developed by Lloyds, but the damage would agree with that observed on the hull. Sky News has an animated reconstruction of this scenario.
Animation Details Cruise Liner’s Final Route
Why did the Costa Concordia roll over and why did it roll to starboard? Ever since the capsizing of the Lusitania in 1914 and the Andrea Doria in 1956, in which both were capsizes were related to asymmetrical flooding, cruise ships have been designed to avoid flooding on one side of the ship. If the roll had started once the ship was intentionally grounded by the captain, that would have made more sense. A ship partially supported by the bottom can become unstable and roll. According to passengers, however, the ship started to roll shortly after they felt the initial grounding, well before the captain turned into shallower water. Also, the ship began to roll to starboard, in the direction away from the observed damage. Was there additional unobserved damage on the starboard side? If so, then the question of where the ship initially grounded is again raised and again there is no clear answer. Likewise, why the ship rolled as quickly as it did and why it rolled away from the side of the ship with the observed damage is unclear.
The ship blacked-out after the grounding. Was this cause or effect? The Costa Concordia is a diesel-electric powered ship which means that a loss of the electrical system also means a loss of engines and steering. This could have caused the ship to go off course and hit the rocks. Earlier this year, Cunard’s Queen Mary 2, also a diesel electric ship, suffered a black-out due to a failure in the capacitors in the harmonic filters. Thus far, however, we have heard no such reports from the Costa Concordia. The black-out could have been the result of the grounding rather than contributing to it. Pending a further investigation, no one knows.
Image No. 24 here:
http://www.theatlantic.com/infocus/2012/01/inside-the-wreck-of-the-costa-concordia/100229/
Shows a strip of steel from the ship’s hull, peeled out and folded over on itself like a strip of bacon, on the Le Scole rock. That seems to be at least one of the major points of impact.
I watched the animated graphic and it appears that the ship made a sharp turn to starboard to return to shore-maybe that contributed to the starboard roll.
Andy, thanks for that link! That is the first evidence I’ve seen from the bottom in the area they purportedly hit. I’m betting there is a veritable junk yard of debris down there and it will be interesting to see what develops as the bottom in that area is mapped and other debris are located. A good magnetometer and bottom mapping sonar study are definitely indicated.
The damage on the port side appears to be gouging as opposed to peeling strips of hull metal like that….
I watched that graphic too, and the maneuver they executed wasn’t at all the way it has been described previously. It looks pretty clear that they maneuvered using the thrusters, so they had to have electrical power of some kind back in order to do that. It’s always possible to kick the main breakers off line for any number of reasons, but until the engineering spaces go in extremis due to flooding or fire, many times some power can be restored at least for a time. There are pictures of the ship lighted up while it was sinking so some power must have been restored.
Great questions Rick, and I appreciate the ongoing analysis here. No telling what is in store with this wreck, and there is still a lot on the line.
Bob, after the ship blacked out, the emergency generators which are usually high up in the ship, appeared to kick in, as they are designed to do. This gave the captain control of the rudders, access to his electronics and apparently, bow thrusters. We are beginning to get reports from other officers aboard the ship that the engine rooms flooded quickly and were effectively gone not long after the grounding.
John Konrad over on the gCaptain blog does a good job narrating the AIS plot animation. See John Konrad Narrates the Final Maneuvers of the Costa Concordia. The interesting new element that he adds is that he assumes a current pushing the ship toward shore. I haven’t heard or read anything about the currents but the assumption makes sense if only because there was no other obvious means for the ship to move towards shore without the addition of an external force. It there was a current my original speculation that the ship rolled to starboard after grounding the second time near the island make more sense again. Rather than the momentum of the turn causing the starboard list, however, current pushing along the length of the port side of the hull may have provided enough force to start the roll. The huge volume of water inside the hull had to provide more force to continue the process until the hull was far enough down so as to allow downflooding from through ports and open doorways.
Again, more speculation, but we are getting more information all the time.
Capt. John’s narration is excellent. I like his analysis and his description of what happened makes a lot of sense. I would note that the vessel has bow and stern thrusters, and I suspect they used both. The black box analysis will be very interesting to read…
I spent 20 years on Active Duty in the Navy, with a significant portion in various shipyards servicing aircraft carriers. I’ve seen some pretty big machinery in my day, and that bacon-strip piece of hull metal looks very much like a chip off of a large machine tool; and I think that is a good comparison to make here. There are huge metal shapers that have an enormous moving bed that the workpiece is bolted to, and the cutting tool is held in an enormous immobile tool holder. In operation, the bed slides back and forth and the work is moved against the tool, and that is essentially what I think happened here.
The Costa Concordia was doing almost 15 knots when it hit whatever it hit. If the hull dragged across the bottom like I think it did, I can certainly imagine how the right piece of rock could act like an immovable machine tool, and carve pieces of hull plate off the bottom as the ship forced itself over the reef, probably using main propulsion, at least until they lost main power. The momentum a ship that size has would carry it quite a way, and for it to lose speed as quickly as it did tells me it must have dragged itself across the bottom extremely hard to slow down that fast, and I think that means her hull had strips peeled off that caused instantaneous catastrophic flooding.
On a side note, I’d like to see what the screws and rudders look like right now…I wonder how badly damaged they were in the grounding. That would tell us a great deal too, especially if one side is more heavily damaged than the other.
Machinists talk about “speeds and feeds” when operating a machine tool, and it sure looks like Costa Concordia got the speeds and feeds just right when it hit a piece of rock that was tougher than the steel hull. If she scraped over the rocks at 15 knots, then there probably isn’t much watertight integrity left in the hull.
Rick, you mentioned that these hulls are designed to prevent asymmetrical flooding, but if you open all of those compartments to the sea all at once, that probably exceeds the hull’s design and stability standards.
We shall see…
I am still not certain that I buy Konrad’s assumption about current. There have been reports of winds of 12 knots which would have blown the ship shoreward. The ship has no shortage of windage.
One other possibility, mention by Simon Miller in another post, was that the thrusters may have contributed to her capsizing. The ship had both bow and stern thrusters. When the ship lost steerage way after the turn, the captain might have used them to move the ship sideways.
My guess is that the only damage to the bottom of the ship will be from the final grounding. It looks to me that the ship sideswiped the ledge off le Scole and did damage primarily to side of the ship to port. The 150′ x probably 10-20′ high gash along the portside would let in a vast amount of water very, very quickly
Asymmetrical flooding is something that all cruise ships are designed to avoid. Even if more compartments are breached than will allow the ship to say afloat, the goal is to have the ship sink without excessive list. A level ship gives passengers and crew a chance to get into life boats and rafts. My guess is that we will find that most of the bodies found below decks were trapped as the ship rolled on its side.
I think the passengers would have been better off if the captain anchored as soon as he could slow the ship down. It is looking more and more like the second grounding is what caused the ship to roll.
Leaving aside for a moment the initial showboating/grounding, in the aftermath do you think the captain’s actions indicate that he believed that he could bring the ship in safely? The animation indicates he at first manuevered for the port, but without power/engines found he could not bring it to a stop to anchor. It does appear that the hard to starboard was to either bring the ship back to the port or at least stop the forward momentum. Apparently he decided to keep the passengers calm and delay beginning evacuation procedures, which were not well understood by most of the passengers or crew. Meanwhile one can assume that he was asking for assessments of the damage and the inflow, which it seems would have indicated that the ship was going to sink. At this point it appears he would have had little choice but to ground the ship intentionally. And here is where is his earlier decision to delay, it would appear, turned deadly. As the ship grounded to starboard, it looks like this is when it rolled 70+ degrees, making progress to evacuation points extremely difficult and launching boats nearly impossible.
My other question relates to the initial grounding. Without clear photos of the stern and the starboard side, there is much that the public does not know at this point. What is your interpretation of photo #30 in Andy Hall’s post above? It would appear that this is the starboard side which is holed. This could have occurred in the “second” grounding. Could it have occurred in the “first” grounding, ie, off of Le Scole? That is to ask you, is the Lloyd’s List AIS data reliable that only the port side grounded off of Le Scole?
Again, we are all speculating. At this point all we can be sure of is how little we know. I definitely do not want to speculate about what the captain was thinking in the period after the grounding.
It appears from the animation that the captain took reasonable action immediately following hitting the ledge off Le Scole rock. Without engines, the ship was still traveling at a considerable speed and he appears to have acted prudently to get the weigh off the ship. He obviously did not want to run into the port breakwater or to drift off into the Tyranean Sea. Until the ship slowed down, he could neither anchor nor launch the lifeboats.
Now we all get into to an area where we can only speculate about what happened. We don’t know if the damage to the ship was enough to sink her. The 30 meter gash in the port side had to be letting in a vast amount of water. We don’t know if anyone consulted the Damage Control Plan to determine the likelihood of staying afloat based on the information that the captain was getting from his officers and crew regarding the scope of the flooding. Let’s assume that they did everything exactly right. (At this point we might as well give the captain the benefit of the doubt, after he has been blamed for so much.)
They determine that the ship is sinking. Grounding the ship in shallow water seems a prudent course of action. If the bottom is reasonably flat, everything should be fine. If the ship is partially floating and partially supported on rocks or a ledge, however, it can become unstable. Is that what happened to the Costa Concordia? I wish I knew. This possibility is the one that makes the most sense to me, but only as compared to the alternatives.
If a loss of stability due to grounding was at least part of the cause of the ship listing so dramatically, then it is possible that anchoring and discharging the passengers and crew into the boats might have been the safer course, depending on how fast the ship was sinking, and with the benefit of speculative hindsight.
I agree that the fatal mistake was delaying the order to abandon ship. Perhaps the captain thought that running the ship aground in shallow water would keep her afloat and upright and if so that there were greater risks to his passengers associated with launching boats at night. (I just said that I wouldn’t speculate what the captain was thinking, didn’t I. Oh well.)
The $500 million euro question that remains unanswered is why the ship rolled as it did. My guess is instability related to the second grounding but that is only a guess. If anyone has better information or greater insights, I am sure that we would all love to hear it.
Photo #30 in Andy’s link looks to my eye like a damaged section of bulwark, possibly in way of a chock. Presumably that would be high enough up so as to be damaged only when the ship rolled.
Early AIS plots published in a Turkish newspaper showed the ship passing west of Le Scole rock in a narrow passage used only by fisherman. If that was the case damage could have been on both the port and starboard sides. I think the AIS plot showing the ship passing east of the rocks makes a lot more sense. If that is the case it is hard to image how more than the port side could have been damaged.
There are a lot of assumptions as to the whole sequence. Adding to these is where exactly was the Captain? Was he on the bridge? Decisions made on the bridge seem suspect in some respects, and although training does have limits, experienced mariners should make well educated decisions. What are the levels of experience from the rest of the bridge team?
Thanks again for your great explanations of things Rick; this site is conducting the most interesting conversation about this incident, and I like the different informed views, and even the speculation. I’ll stand fast with my speculations as stated until we see some proof of actual conditions of the hull.
Question: Considering the increasing nasty conditions inside the ship from (at least) a great deal of rotting food, would small RPVs be useful inside for assessing the condition of the hull?? How hard would it be to pilot a remote into the engineering spaces on the Starboard side, and see what the grounded hull looks like from the inside??
On a related matter that should not be speculative, I hear this morning that crews have the go-ahead to begin installing a special plate, with a valve on it, that they will lance through the hull into the fuel tanks to begin recovering some 500,000 gallons of fuel. From what I have seen, the main tanks are accessible through the hull in the area right behind the extended stabilizer.
Considering that the fuel is less dense than seawater, and assuming they will ballast the tanks and use seawater pressure to help push the fuel into the recovery lines, as the amount of fuel decreases and the amount of seawater in the tanks increases, will that add more stability that will tend to keep the hull grounded in place, or will that extra weight add impetus for the hull to slide off the ledge it is on and into deeper water??
I’m sure that’s a consideration, but not sure how big. Comments??
Another item to speculate about…exactly what happened to that Starboard stabilizer fin during the grounding?? If it jammed against the rocks or was bent and could not retract into its slot, what kind of damage could be done it it got forcibly ripped off the hull?? If it didn’t get ripped off, but was jammed at an extreme angle, could it have caused that immediate list to Starboard??
Keep in mind we are talking about enormous forces at work here. The G loads that had to spike on some pieces of the hull would be tremendous, instantly exceeding the strength of the hell by several degrees of magnitude. We don’t know yet, but it sure looks like what slowed the ship down from 15 knots to almost a dead stop was the force the hull imparted to the earth’s crust when it snapped that enormous hunk of granite off. The rest of the ship’s momentum was absorbed by the shelf it apparently dragged itself over.
Again, it’s a matter of speeds and feeds. Feed the hull against that tool of a rock to slowly, and the hull bounces off or slowly grinds to a halt. Feed it fast enough (impossible to do) and it might skip over it all with little more than scratched paint and a few tears. But with the right momentum on that enormous hull and at a speed of 15 knots or so at impact, you peel the hull like an avocado in some places and slice open what doesn’t peel off in others.
The end result is still near instantaneous flooding on one side that is sufficient to lift that boulder and the seawater that is flooding in behind it free and clear. I realize these ships are built to minimize asymmetrical flooding in most conditions, but not under all conditions.
Lets see what other hard evidence the divers come up with….
There are some interesting photos posted on the Huffington Post at http://www.huffingtonpost.com/2012/01/26/costa-concordia-disaster-new-photos_n_1233951.html#s641053. The Costa Concordia is grounded on the Punta Gabbianara. What’s interesting is the starboard list is moderate — enough so that the launching of all of the starboard boats is clearly visible. All of the davits are outboard, and it appears that all but 2 of the boats are away. From the reporting, it’s not clear to me how long after the grounding there that the ship rolled to 80 degrees as it is shown in the later photos and FLIR video. I know you avoid speculation, but the FLIR video reportedly shows several hundred passengers forced to crawl down the port side; thus it may be that many more were able to evacuate on the boats after the grounding (from what I’ve been able to discern, no boats were launched before the grounding on Punta Gabbianara). The other interesting item is that the starboard anchor is visibly set. I haven’t been able to see from other photos the position of the port anchor. All this will eventually become clear, but given the criminal charges the facts may not be released until trial. In the meantime, the clues from photos are interesting.
I agree. Lots of fascinating bits of information. Not much of it fits together yet. And I am not opposed to speculation. At this point hat is all we can do, lacking so many of the facts.
It will be interesting to learn why all passengers were not able to disembark on the starboard side. It should not have been a boat capacity issue. Was the evacuation as chaotic as described so that many did not board the boats in time? How much was the evacuation slowed by the ship’s personnel telling the passengers to go back to their cabins? Was crew training inadequate or where they given bad orders by the officers?
Could the live weight of the passengers have anything to do with the starboard roll? With the shore so close to the starboard side, it seems to me that the people on board….4000 or so times say 200 lbs…about 400 tons…all rushing to starboard for safety might start the roll…and if she was top heavy that might exacerbate the situation. I’m a novice here…just wondering.
There are lots of possible causes for the roll. Passenger weight on a cruise ship this size was no doubt contributory but probably not sufficient. There was also an over ten knot wind blowing on the side of the 13 deck ship which might has also contributed. My guess is still a loss of stability as the ship grounded on an uneven rock ledge. With luck we may learn the cause in a year or so.