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  #286  
Old Today, 09:03 AM
IEWinkle IEWinkle is offline
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Quote:
Originally Posted by Heiwa View Post
I am happy to see that progressive flooding through watertight (WT) doors aft is discussed as being a (the proximate?) cause of the following capsize.
Assuming watertight engine compartments #4, 5, 6 and 7 were upflooded due to the side contact damages, what is the new draft and trim on stern?
Assume that deck #4 is the bulkhead deck and that deck #5 has the mooring deck aft and that the space between decks #4 and 6 is a weathertight superstructure, would deck #5 aft come below water due to upflooding of compartments #4-7. I doubt it. I think deck #5 aft was above waterline after the contact and that the vessel was floating and stable upright. So no down-flooding via doors on the mooring deck is expected.
Thus, the only possibility that ship trims more on the stern is actually progressive flooding through open W/T doors aft of the engine room (compartment #4).
Did such doors exist?
What do compartments #2 and 1 contain? On deck #2? Engine stores? If so I expect W/T doors to be fitted there (and that they should have been closed at sea). On decks #3 and 4? Ship stores? With W/T doors (that are not allowed by SOLAS!)? Actually it doesn't matter because the decks are not watertight and open W/T doors on deck #2 will cause compartments #2 and 1 to fill up (deck #5 aft will be submerged) while GM and GZ becomes 0 = capsize. It will be interesting to see what the Italian Accident Investigation Commission will find.
The drafts are quoted in my post 57 on Simulating Costa Concordia based on the night-time shot of the vessel as is reached the shore. This gives about 2 m of freeboard on the centreline of the bulkhead (mooring) deck aft which becomes about -2.2 m at the starboard corner due to the 13.2 degree list - leading to progressive flooding through any sounding/vent pipes in that area by this stage. The analysis in post 58 following suggests some of the possibilities for flooding to get to this stage. Which if any doors were left open will have to wait until a proper examination of the vessel is undertaken. If there was no flooding of structures outboard of the engine casings above the 7.2 m deck level the vessel would have survived 5 compartment flooding without significant list. Perhaps this is what led to the Master's indecisiveness over evacuation? SOLAS compartmentation would assume flooding thoughout the depth of the vessel including the double bottom and side decks above 7.2 m. Under these assumptions she would be lucky to survive 3 compartment damage!

See post 294 below!

Last edited by IEWinkle : Today at 01:43 PM. Reason: Addition
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  #287  
Old Today, 09:13 AM
Heiwa Heiwa is offline
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Quote:
Originally Posted by Starbuck1 View Post
Heiwa,

For consistency of reference, lets use the deck numbering of the plans available, which have the Olanda Deck as Deck 1, the first passenger deck. Below that are 0, A, B, & C decks.
According SOLAS/international nomenclature tank top (of double bottom) is deck #1 - so
Solas Deck# 1 = Costa Concordia deck C
Solas Deck# 2 = Costa Concordia deck B
Solas Deck# 3 = Costa Concordia deck A
Solas Deck# 4 = Costa Concordia deck 0
Solas Deck# 5 = Costa Concordia deck Olandia/deck 1
etc
In every stairwell, etc, shall be indicated on what deck # you are numbered from tank top. Then you can call the deck whatever, e.g. Olandia

Solas deck #4 is the bulkhead deck (top of watertight hull) and SOLAS deck #5 aft is the mooring deck and SOLAS deck #6 is top of (wethertight) superstructure.
CC had crew accommodated on SOLAS decks #2, 3 and 4 and passengers on SOLAS deck #5.

A shipowner and maritime admin that do not know how to number the decks on their ships are ... well, not aware of the rules in force.
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  #288  
Old Today, 09:21 AM
CliffordK CliffordK is offline
 
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I suppose I'm surprised about the lack of cross compartmentalization in the ship. So, a hole on the port side causes the starboard side to sink.

I realize the risk of accentuating the list by only flooding compartments on one side of the ship, but there should at least be a method to control the side-to-side flow of water. And good pumps and a ballast transfer might be able to compensate to some extent for compartments flooded on one side of the ship. Compartments should also be arranged to effectively create a double-hull both on the bottom and sides of the ship up a few decks.

I'm a little lost on the state of the watertight doors. But, shouldn't a half a billion dollar ship have 100% automatic watertight doors below the waterline, with a manual override? Sliding doors could even be utilized to dynamically manage water, as long as they didn't get jambed with debris, so perhaps some kind of a valve/pump system would be better to treat the lower decks as extended ballast areas as necessary.

Immediately after the grounding, the 1000+ crew members should have been deployed to visually inspect the compartmentalization, with only vertical egress being preserved in vital locations. Although, the bridge should have adequate monitoring of the compartment status including all doors and whether the compartments are wet or dry. Crew quarters and lower decks should have also been sealed, with only vital personel having access to the engine and electrical areas.

What is that about overtopping bulkheads? Wasn't that the fatal flaw of the Titanic. 100 years later, hasn't it been solved. I realize the safety issues of egress, but there is also safety issues of preventing the bulkheads from being overtopped.

The other issue that I haven't seen commented on is that the Costa Concordia apparently had 6 primary diesel-electric generators located in two consecutive compartments. So, a single incursion can knock out 100% of the ship's power.

While the transformers and control panels were located above the generators, it is unclear what isolation they had. Were they 100% above the water line? Electrical systems should be routed higher in the ship whenever possible.

The 6 generators should be arranged from bow to stern, with as much isolation and compartmentalization as possible.

Ten minutes after the impact, the ship was dark and adrift. Had it drifted away from the island, it would have had little chance of self rescue. Had it drifted into a vertical cliff, the damage would have been farm more severe. With that in mind, the crew's first contact with the Italian Coastguard should have indicated an impact and critical engine failure, rather than a minor electrical problem.

But, had the power systems had adequate isolation, including isolated propulsion systems, and perhaps a secondary midship propulsion jet, then at least the ship would not have been at the mercy of the sea.

Lifeboats?

What is up with providing poles to manually push the lifeboats away from the ship. All the lifeboats should be equipped with wheeled or tracked crawlers to assist with deployment. They should be able to deploy with a list up to 110 degrees, if not a full 180 degrees. If the ship had listed quicker, and the captain delayed lifeboat deployment longer, then 100% of the starboard lifeboats would have been inaccessible (covered with water), and 100% of the port lifeboats would have been inoperable.

What about redundant capacity with inflatables, as well as redundant life preserver capacity?
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  #289  
Old Today, 09:29 AM
Heiwa Heiwa is offline
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Quote:
Originally Posted by IEWinkle View Post
The drafts are quoted in my post 57 on Simulating Costa Concordia based on the night-time shot of the vessel as is reached the shore. This gives about 2 m of freeboard on the centreline of the bulkhead (mooring) deck aft which becomes about -2.2 m at the starboard corner due to the 13.2 degree list - leading to progressive flooding through any sounding/vent pipes in that area by this stage. The analysis in post 58 following suggests some of the possibilities for flooding to get to this stage. Which if any doors were left open will have to wait until a proper examination of the vessel is undertaken. If there was no flooding of structures outboard of the engine casings above the 7.2 m deck level the vessel would have survived 5 compartment flooding without significant list. Perhaps this is what led to the Master's indecisiveness over evacuation? SOLAS compartmentation would assume flooding thoughout the depth of the vessel including the double bottom and side decks above 7.2 m. Under these assumptions she would be lucky to survive 3 compartment damage!
Progressive flooding does not place through sounding pipes, which are always closed, and hardly through vent pipes (as they are small dia, but we do not know). More interesting are the hinged/cleated weathertight doors on the mooring deck #5 and their sill heights (to protect water entry into the superstructure, etc.).
I assume the engine casing at centerline starts on (bulkhead) deck #4 and ends at the funnel bottom.
But what is the height of deck #4 above keel?
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  #290  
Old Today, 09:54 AM
IEWinkle IEWinkle is offline
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Quote:
Originally Posted by Heiwa View Post
Progressive flooding does not place through sounding pipes, which are always closed, and hardly through vent pipes (as they are small dia, but we do not know). More interesting are the hinged/cleated weathertight doors on the mooring deck #5 and their sill heights (to protect water entry into the superstructure, etc.).
I assume the engine casing at centerline starts on (bulkhead) deck #4 and ends at the funnel bottom.
But what is the height of deck #4 above keel?
I will accept your point about the sounding pipes but will not accept that progressive flooding does not take place down vent pipes as this was the cause of the initiation of the loss of the 'Derbyshire' through flooding of its fore peak tanks.

I am assuming the engine casing (of unknown length but half the breadth of the ship) starts at 7.2 m above keel (the base of deck A) - the only way to explain the limitation of only about 12,000 tonne of water in 5 flooded compartments to acheive the flooded condition we have all been discussing and the continuation of a stable upright condition for so long. This deck and 0 above seem to have provided the necessary buoyant lifebelt to stop the ship sinking straight away! See post 294 below.

No access information seems to be available for the mooring deck, but the flooding to immerse this deck's corner must have taken place internally to produce the initial list.

Last edited by IEWinkle : Today at 01:45 PM. Reason: Addition
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  #291  
Old Today, 10:33 AM
IEWinkle IEWinkle is offline
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Quote:
Originally Posted by CliffordK View Post
I suppose I'm surprised about the lack of cross compartmentalization in the ship. So, a hole on the port side causes the starboard side to sink.

I realize the risk of accentuating the list by only flooding compartments on one side of the ship, but there should at least be a method to control the side-to-side flow of water. And good pumps and a ballast transfer might be able to compensate to some extent for compartments flooded on one side of the ship. Compartments should also be arranged to effectively create a double-hull both on the bottom and sides of the ship up a few decks.

Immediately after the grounding, the 1000+ crew members should have been deployed to visually inspect the compartmentalization, with only vertical egress being preserved in vital locations. Although, the bridge should have adequate monitoring of the compartment status including all doors and whether the compartments are wet or dry. Crew quarters and lower decks should have also been sealed, with only vital personel having access to the engine and electrical areas.

What is that about overtopping bulkheads? Wasn't that the fatal flaw of the Titanic. 100 years later, hasn't it been solved. I realize the safety issues of egress, but there is also safety issues of preventing the bulkheads from being overtopped.

The other issue that I haven't seen commented on is that the Costa Concordia apparently had 6 primary diesel-electric generators located in two consecutive compartments. So, a single incursion can knock out 100% of the ship's power.

While the transformers and control panels were located above the generators, it is unclear what isolation they had. Were they 100% above the water line? Electrical systems should be routed higher in the ship whenever possible.

The 6 generators should be arranged from bow to stern, with as much isolation and compartmentalization as possible.

Ten minutes after the impact, the ship was dark and adrift. Had it drifted away from the island, it would have had little chance of self rescue. Had it drifted into a vertical cliff, the damage would have been farm more severe. With that in mind, the crew's first contact with the Italian Coastguard should have indicated an impact and critical engine failure, rather than a minor electrical problem.

But, had the power systems had adequate isolation, including isolated propulsion systems, and perhaps a secondary midship propulsion jet, then at least the ship would not have been at the mercy of the sea.

Lifeboats?

What is up with providing poles to manually push the lifeboats away from the ship. All the lifeboats should be equipped with wheeled or tracked crawlers to assist with deployment. They should be able to deploy with a list up to 110 degrees, if not a full 180 degrees. If the ship had listed quicker, and the captain delayed lifeboat deployment longer, then 100% of the starboard lifeboats would have been inaccessible (covered with water), and 100% of the port lifeboats would have been inoperable.

What about redundant capacity with inflatables, as well as redundant life preserver capacity?
There was no significant longitudinal subdivision in this ship with the exception of what appear to be two continuous decks under the bulkhead deck to port and starboard. It seems to have been these that contained the initial influx of water and kept the ship near upright for the best part of an hour - otherwise with 5 compartments flooded the ship would have sunk straight away. Substantial wing tanks in the side might have helped in this extreme damage case but would have complicated the operation and survival of the vessel in other accident scenarios (i.e. there is no perfect compartmentation for survival - it depends on the accident case and its likelihood - this was the most extensive side raking damage to any passenger ship since the loss of the 'Titanic'). Speaking of the 'Titanic', all ships can suffer overtopping of their bulkheads once the bulkhead deck goes below the waterline as water floods up vertical access paths - it is interesting that this did not happen in this case (at least before the final capsize) despite apparently fatal 5 compartment damage!

It is normal for six sets of diesel generators to be set in two adjacent compartments as in this case. It is important to be able to ventilate the engines and exhaust them thought one common space via the funnel to preserve the utility of the spaces above. It is unfortunate that such side damage not only knocked out all the electrical power but also the propulsion motors and probably all the electrical control systems as well. The latter are of little use if the power supply is under water!

Despite the loss of all power within ten minutes (the time it is assumed it took to wipe out the forward generators), the auxiliary generator was able to cope with all the evacuation demands. The fact that the crew did not declare an emergency despite being fully aware of the flooding by this time speaks volumes about the incompetence of the Master and his officers. Had he done so, all passengers could have been safely in lifeboats and the crew in their liferafts as the SOLAS Rules intended long before the vessel ran aground and capsized. The ship performed far better than could have normally been expected in the event of such an 'avoidable' incident - it was the crew who were the lamentable failures.
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  #292  
Old Today, 11:20 AM
Heiwa Heiwa is offline
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Quote:
Originally Posted by IEWinkle View Post
The fact that the crew did not declare an emergency despite being fully aware of the flooding by this time speaks volumes about the incompetence of the Master and his officers. Had he done so, all passengers could have been safely in lifeboats and the crew in their liferafts as the SOLAS Rules intended long before the vessel ran aground and capsized. The ship performed far better than could have normally been expected in the event of such an 'avoidable' incident - it was the crew who were the lamentable failures.
Regardless - abt 4 100 persons were, we are told, evacuated before capsize using ship's LSA and another abt 100 that stayed up top could later, after capsize, walk on the upper, port flat side (list 90°) and climb down ladders to boats coming from Porto Giglio. A few people stayed even longer ... until ship sank on the rocks with list 45°.
So the Master, officers and crew cannot be blamed for bad evacuation, etc. 99.25% of all aboard were saved, we are told. About 4 200 persons! And all were home within 48 hrs! Fantastic! And a few got upset having their holiday cut short and want $100million damage.
But you are right! Ships are not built or designed to withstand damages due speeding by rocky shores ripping open their sides. Any shipowner doing it is incompetent and not diligent and ... his insurance is not valid. Basic. Actually the ship owner and his top senior shore management should be put in jail for good. The marine industry cannot be run by clowns like them.
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  #293  
Old Today, 12:11 PM
IEWinkle IEWinkle is offline
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Quote:
Originally Posted by Heiwa View Post
Regardless - abt 4 100 persons were, we are told, evacuated before capsize using ship's LSA and another abt 100 that stayed up top could later, after capsize, walk on the upper, port flat side (list 90°) and climb down ladders to boats coming from Porto Giglio. A few people stayed even longer ... until ship sank on the rocks with list 45°.
So the Master, officers and crew cannot be blamed for bad evacuation, etc. 99.25% of all aboard were saved, we are told. About 4 200 persons! And all were home within 48 hrs! Fantastic! And a few got upset having their holiday cut short and want $100million damage.
It is great that 99% of the people on board this vessel got off safely - but it would have been 100% if the evacuation had been started earlier - that was down to the incompetence of the Officers in this case (of course they can be blamed) and if I was a family member of one of those that didn't make it I would be after them for all I could get!
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  #294  
Old Today, 01:15 PM
smartbight smartbight is online now
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Preliminary scaled drawing

This preliminary scaled drawing may help visualize the discussion.

Questions:

We are thinking that the motor room may be in compartment 5 instead of 4 as it gets fairly narrow in the stern around comp. 4. ?

Is the center line open space, between rows of cabins, on most decks, a 'utility' corridor for all the 'hotel' piping, AC ducts, electric cables, etc. ?
Attached Thumbnails
Costa Concordia, 80 deg list, really scary !!-cc_profile-d14.jpg  
Attached Files
File Type: pdf profileCCONCORDIA8_Rev1.pdf (188.0 KB, 8 views)
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  #295  
Old Today, 01:52 PM
Heiwa Heiwa is offline
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Quote:
Originally Posted by smartbight View Post
This preliminary scaled drawing may help visualize the discussion.

Questions:

We are thinking that the motor room may be in compartment 5 instead of 4 as it gets fairly narrow in the stern around comp. 4. ?

Is the center line open space, between rows of cabins, on most decks, a 'utility' corridor for all the 'hotel' piping, AC ducts, electric cables, etc. ?
Suggest you renumber the decks 1 to 17 (as per SOLAS).
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  #296  
Old Today, 02:17 PM
smartbight smartbight is online now
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Quote:
Originally Posted by Heiwa View Post
Suggest you renumber the decks 1 to 17 (as per SOLAS).
We'll stick to the 'Tourist' brochure for a while, or we'll get totally confused. This is not for a T&S booklet

Please post any additional details you may have on this ship.
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  #297  
Old Today, 03:30 PM
CliffordK CliffordK is offline
 
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Several of the people survived because they jumped off the ship and swam to the shore in the middle of the winter. That should not be considered part of a successful rescue plan.

Several lifeboats failed to deploy, and several of the lifeboats made multiple trips between the ship and port to pick up multiple passengers. While they were close to a small port, this would not have been universally possible.

The ultimate survivability of this accident appears to be more luck than competent planning and execution of the evacuation by the crew (except the captain who had excellent planning an excecution of his own evacuation).

As I mentioned above, lifeboats rubbing along the sides of the ship is an old and well documented phenomenon. A wheeled/crawling system for the lifeboat deployment would have improved evacuation, and meant that passengers would not have had to exit out of undeployed lifeboats.
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  #298  
Old Today, 04:10 PM
Chickadee Chickadee is offline
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Quote:
Originally Posted by Heiwa View Post
.
Actually the ship owner and his top senior shore management should be put in jail for good. The marine industry cannot be run by clowns like them.
Costa Crociere is Carnival (talking about clowns) owner is "Micky" Arison and family, multi-billionaire Israeli Americans... These people, in jail? Don't hold your breath! lawyers will bow and express their solidarity and sympathy for the harsh times "Micky" had to endure! They'll have to find some Costa Crociere' underdog to hang, but insurances will have to pay? Even if the ship captain (already publicly damned) reportedly said he was insistenly ordered to carry out the salute to the island manoeuvre by ship owner Costa Crociere.

here: http://www.guardian.co.uk/world/2012...-island-claims

From the same source: "Schettino had always been considered one of the firm's best captains"
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  #299  
Old Today, 04:21 PM
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A quick note: this thread is in the Stability forum so let's keep this thread mainly for discussion of the ship's stability.
There is a more general thread discussing the incident (navigation, salvage, etc.) at Last voyage for Costa Concordia cruise ship for non-stability aspects of the disaster.
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