Costa Concordia (Titanic 2012)

[westernman]

They planned to be no more than 300m from the island for the sail past as confirmed by the captain. This should have put them at 150m from the rocky pinnacle - as also confirmed by the captain (about 1/2 of a boat length).

It is easily possible that the island is 100m or more from its charted position. It is offshore and the last survey is probably at least half a century old.

GPS error can easily reach 30m with a 95 % certainty (that is what most GPS units use when they give you an accuracy figure). That means 5% of the time your actual position is more than 30m from where the GPS is telling you.

So his margin of error = 150m - 100m - 30m = 20m
95% of the time he will just make it. With just half his beam to spare.

My guess is that some one saw the rock coming up awfully close, they panicked and turned to starboard at the last minute pushing the stern onto the rocks. Even at half a boat length, that turn would end in disaster. And it could well have been a lot less.

I also guess that the bridge crew were relying on the island being exactly where there electronic charts showed it to be.

If they had overlaid the radar they might have noticed the difference.

 

[Boomshanka]

This video shows the evacuation to a lifeboat onboard... a bit of panic, but I would imagine it could be worse... just one thing that seems weird though, I thought it was dark at the time

 

[SailorBill]

I'm guessing most passengers survived more by luck than good judgement.

 

[Kukri]

They planned to be no more than 300m from the island for the sail past as confirmed by the captain. This should have put them at 150m from the rocky pinnacle - as also confirmed by the captain (about 1/2 of a boat length).

It is easily possible that the island is 100m or more from its charted position. It is offshore and the last survey is probably at least half a century old.

GPS error can easily reach 30m with a 95 % certainty (that is what most GPS units use when they give you an accuracy figure). That means 5% of the time your actual position is more than 30m from where the GPS is telling you.

So his margin of error = 150m - 100m - 30m = 20m
95% of the time he will just make it. With just half his beam to spare.

My guess is that some one saw the rock coming up awfully close, they panicked and turned to starboard at the last minute pushing the stern onto the rocks. Even at half a boat length, that turn would end in disaster. And it could well have been a lot less.

I also guess that the bridge crew were relying on the island being exactly where there electronic charts showed it to be.

If they had overlaid the radar they might have noticed the difference.

Extremely good point.

 

[neale]

Mike, there's a french newspaper report further up ^^^ that quotes passengers out on the deck seeing the rock in question and it came up to the level of the fourth 'floor' of the boat... hardly near to the surface by those accounts!

The outer of the larger two islets at Le Scole seems to be 9m above sea level, the inner one possibly 11m. I guess that could easily be construed as level with the 4th floor.

 

[prv]

I also guess that the bridge crew were relying on the island being exactly where there electronic charts showed it to be.

Have to say I just find this hard to believe. Incautious yachtsmen sometimes do it, but surely the Master of a 4000-passenger cruise ship knows that it's irresponsible to rely on a single source of navigation information for something so critical?

Pete

 

[Kukri]

It's a good while back, twenty years or so, but I remember the Master of a 117,000 ton ship parking her fairly firmly on a sandbank for acouple of hours till the tide made, after relying on a single radar bearing and distance of what he thought was the Sandettie light vessel and was in fact a fishing boat...his Marine Super entirely failed to see the funny side of what was a very narrow escape...

 

[Neil_Y]

Now it's difficult to tell what is fact and speculation, but this site with an image from Turkish AIS position shows course between the rocky outcrops in a pretty small channel for this size of boat.

If you're not on course with something that long you can't alter course much without the stern moving 10's of metres to the side, It's clear it was steering that caused it to hit as the stabiliser fin is still intact.

If this is what they did then going through that gap would always be high risk, I wonder how often it was done?

Sad and it seems pointlessly close to hazards.

http://www.denizhaber.com/res_upload/1/isolascole.jpg

 

[Boomshanka]

Looks like the CEO is confirming the 'fly past' hypothesis :

"Costa Cruises boss Pier Luigi Foschi accused Capt Francesco Schettino of sailing too close to a nearby island in order to show the ship to locals."

video here on BBC: clicky

 

[Deleted User YDKXO]

They planned to be no more than 300m from the island for the sail past as confirmed by the captain. This should have put them at 150m from the rocky pinnacle - as also confirmed by the captain (about 1/2 of a boat length).

It is easily possible that the island is 100m or more from its charted position. It is offshore and the last survey is probably at least half a century old.

I have been boating around the Med for a few years and whilst I agree that Med digital charts are often less accurate than the UK and certainly not infallible, I have never come across a bloody great sticky out rock so far out of position that it is a hazard to navigation. You would think that if that was the case, it would have been hit many times by other vessels and either corrected on the charts or at least a buoy placed there. Also you mentioned radar. Shouldn't somebody have been keeping a radar watch, if only to identify small boats, and shouldn't they have seen a return from the rock on the screen? Wouldn't the guard alarms be sounding off as well?
IMHO this is not an accident that can be blamed on GPS or charting errors. More likely fatal inattention on the bridge or simply underestimating the sea room needed to turn a ship of this size to starboard to make the 'fly by' past the harbour and maybe aggravated by wind and currents. All conjecture but I think if I was the skipper, I'd be blaming an uncharted rock too!

 

[Kukri]

Humm; the unauthorised flyby is pretty well vouched for, it seems:

http://news.sky.com/home/world-news/article/16149739

 

[westernman]

I have been boating around the Med for a few years and whilst I agree that Med digital charts are often less accurate than the UK and certainly not infallible, I have never come across a bloody great sticky out rock so far out of position that it is a hazard to navigation. You would think that if that was the case, it would have been hit many times by other vessels and either corrected on the charts or at least a buoy placed there. Also you mentioned radar. Shouldn't somebody have been keeping a radar watch, if only to identify small boats, and shouldn't they have seen a return from the rock on the screen? Wouldn't the guard alarms be sounding off as well?
IMHO this is not an accident that can be blamed on GPS or charting errors. More likely fatal inattention on the bridge or simply underestimating the sea room needed to turn a ship of this size to starboard to make the 'fly by' past the harbour and maybe aggravated by wind and currents. All conjecture but I think if I was the skipper, I'd be blaming an uncharted rock too!

No need for a buoy on it. It sticks 4m or more up in the air!!!

I have come across the entrance to a port which is 100m from where is should be not far from my home port. Actually the entrance is not very visible and the first time I went there, I could not see the entrance and had a bloody great wall in front of me. I rechecked the GPS position, and then checked the chart and landmarks and realized that the entrance was 100m to the west of where it was marked.

The island could easily be 100m away from its charted position. However, the rock which is sticking out will be at exactly the distance shown on the chart from the island and hence could be 100m away from its GPS coordinates in exactly the same direction as the whole island. The surveys carried out 50 years or more ago where very accurate in relative terms - but they would have difficulty triangulating the position of the island to within a few meters.

If the captain and crew were relying purely on GPS and the digital charts, then effectively the rock and the whole island could easily be 100m away from where they expected it to be. And the captain planned to be only 150m away from the rock anyway!

Then add the GPS uncertainty on to that, and they could easily be brushing it as they go by.

I have been told that some islands in French Polynesia where found to be up to 7 miles away from their charted positions when GPS first came out. I guess that amount of error has been corrected now (just change the coordinates at the bottom of the chart), and on the large scale passage making charts you can't see the difference anyway.

 

[haydude]

My guess is that some one saw the rock coming up awfully close, they panicked and turned to starboard at the last minute pushing the stern onto the rocks. Even at half a boat length, that turn would end in disaster. And it could well have been a lot less.

I also guess that the bridge crew were relying on the island being exactly where there electronic charts showed it to be.

If they had overlaid the radar they might have noticed the difference.

It sounds a likely theory to add to the GPS error. Beside being unforgivable having allowed for very small margins. There is a marina just on the path, what about local small vessels traffic? Just for that reason as a skipper I would not have ventured so close.

 

[Deleted User YDKXO]

No need for a buoy on it. It sticks 4m or more up in the air!!!

My point was that if it was known this rock was out of position on charts and therefore a hazard at night, the authorities might have put a lit buoy there to warn seafarers.

 

[Cruiser2B]

There is no way that could possibly be attributed to GPS failure; looking out the windows would make it absolutely clear they were going between the islets. While a line drawn on a chart or e-chart may have shown it possible to pass in deep water, the reality is the gap between the 10m contours is only about 5 metres wide. There is no guarantee that there will be a steady gradient from the 10m to 5m contours either and with the ship being 35 m wide and drawing 8.2 m, it would be absolute folly to take it there. I would not be half-surprised if they find an even bigger hole on the starboard side - which might also explain how she ended up on that side.

 

[westernman]

My point was that if it was known this rock was out of position on charts and therefore a hazard at night, the authorities might have put a lit buoy there to warn seafarers.

The whole island might be 100m out of position. But there is almost certainly a light on the island. Once you know where the light on the island is, you know where all the outlaying rocks are relative to that.

Seems to have been a novice skippers error of believing that the charts and GPS are accurate to a few meters.

 

[[32511]]

Sky News reports that Smit have been contracted to remove the fuel oil from the wreck- there's 2380 tons of it.

 

[sigmasailor]

What's wrong with using your eyes for looking outside rather than at those 'nice' electronic screens. For those that have seen the Discovery air crash investigation series it will be familiar. With all those modern aids people tend to forget they have to keep in control instead of relying on electronics; I mean 'fly that plane' or 'sail that ship'.

Still can't understand why a sail-by has to be that close. Nope: I simply do not believe it went between those two small islands; it was close enough to hit some other rock though.

Good thing that Smit get's to do the job. I read they are already on site gathering equipment for oil extraction using 'hot taps'. I like Smit for their 'no nonsense' approach. Their website says it all (www.smit.com); lean and mean.

 

[stillwaters]

I have been boating around the Med for a few years and whilst I agree that Med digital charts are often less accurate than the UK and certainly not infallible, I have never come across a bloody great sticky out rock so far out of position that it is a hazard to navigation. You would think that if that was the case, it would have been hit many times by other vessels and either corrected on the charts or at least a buoy placed there. Also you mentioned radar. Shouldn't somebody have been keeping a radar watch, if only to identify small boats, and shouldn't they have seen a return from the rock on the screen? Wouldn't the guard alarms be sounding off as well?

As most of us in a similar position would probably be doing just that,to not do it on something of this size would totally beggar belief,wouldn't it?
Weren't they also supposed to not sink her,though......?



IMHO this is not an accident that can be blamed on GPS or charting errors. More likely fatal inattention on the bridge or simply underestimating the sea room needed to turn a ship of this size to starboard to make the 'fly by' past the harbour and maybe aggravated by wind and currents. All conjecture but I think if I was the skipper, I'd be blaming an uncharted rock too!

In an interview on Italian TV,the captain claimed the ship was moving sideways when it hit something. However,it must have been moving forwards for that gash to occur (the rock also appears to have entered lower below the waterline than where it finished up,so it possibly tugged the ship down a little as it passed?) Now someone correct this if it's c**p but,assuming the captain's assertion that the ship was moving sideways is true,even on something that big if it was simultaneously moving forward and sideways,(ie turning) would the sideways movement not generally be rotation and therefore only create a noticeable sensation of sideways movement if there was an obvious nearby point of reference,such as a big lump of rock right next to you rather than open water?

 

[NickRobinson]

Yes indeed; to the waiters & entertainment staff who actually stayed & helped, not the officers & seamen crew who bagged the lifeboats shoving women out of the way, if you believe the first hand accounts in the Mail today.

Does anyone believe the Daily Wail?