The listing sequence


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Jim Currie

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I agree with you Michael about the dining room contribution v. facts of life. just pointing out that such an area would contribute.

Sam,

I thought you liked to deal with facts? What weights were added? If none were added then why use a calculation method that requires weights to be added or subtracted?

You write: " both methods, lost buoyancy Vs. added weight, yield the same righting moment."

Perhaps they do but surely the most significant event was the loss of buoyancy?

I am perfectly aware of Charlie's abilities and past life. I do not dispute what he says - merely question.
Charlie was on a quest for a virtual rise in the centre of gravity. You know what causes that. So do I but unless we have dimensions such as Charlie suggests - then I must go with the lost buoyancy cause of the listing sequence.
As I said before; virtual rise in G due to free surface effect is found by dividing the inertia of the surface water in the compartment by the volume of the water displaced. The flood water is not part of the displacement. More flood water - less volume displaced. This might produce a greater virtual rise in an enclosed space where the level in that space remained the same. But the spaces were flooding from the sea and consequently the depth of water and surface shapes were constantly changing. all this before factoring-in the initial list.

You cannot imagine the mathematics but the effect of lost buoyancy is immediately apparent - even to someone with a basic working knowledge of how things float.

I was surveying a very large, six column sem-submersible drilling barge alongside a berth in Rotterdam some time ago. The barge engineer inadvertently forgot to close a WT hatch at the base of the port - forward column. Each column was 45' in diameter and divided horizontally into tank spaces. The result was spectacular but we did not experience any free surface effect - just a very rapid loss of buoyancy - much as did Titanic. I know this because we had a ballast programme on the computer which included all down-flooding conditions. We later simulated the event on it. Actually, these semis are excellent examples of how a floating object reacts to adding or subtracting weights v. down flooding. They are actually submerged using a method of down-flooding. They also have some tricky moments at transition just as the hulls
emerge during the pumping-out process. There is a significant virtual rise of G at that time due to a sudden change in the displacement.
 
Mar 22, 2003
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>>I am perfectly aware of Charlie's abilities and past life.<<

My comment was not directed to any individual. There are many who read these post who do not know what others have done and how that relates to the discussion. Charlie is good friend of mine, and I know how long he has been looking into this particular aspect. I'd love to see him publish his results in the not too distant future.
 
Aug 10, 2002
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Hello All:
I believe Titanic is rather unique among ships that accidentally flooded and sank. She retained her transverse stability and went down by the head, most others lost transverse stability and rolled over before sinking. It is her retention of transverse stability that interests me. In particular I'm investigating whether the lowering of G due to weight added low more than offset the virtual rise in G due to Free Surface. I'm still working on it, when it is done I'll publish it.
Regards, Charlie
 
Jul 9, 2000
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>>It is her retention of transverse stability that interests me.<<

And which retention puzzles the rest of us for the reasons you just mentioned. The retention of transverse stability in such accidents is almost unheard of. Those who turn old ships into artificial reefs attempt to do this by deliberate design, always with very careful planning, but not always with total success.
 

Jim Currie

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Morning Charlie,
you wrote:

"I'm still working on it, when it is done I'll publish it."
I look forward to reading it as I'm sure many herein do.

I recall an officer called on everyone on the boat deck to go to the starboard side to offset the port list. If so, and he thought it might work; what does this tell us about the condition of Titanic?

How many people would be on the boat deck at that time - double the number that got away? if so then we are talking of upward of 1500 people. Using an average of 112 lbs/person that amounts on close to 75 tons located well above the C of G. This weight would increase by a ton for every 20 more people. The original G would have move upward when all these people went so high in the ship. Strictly speaking - the centre of G would rise as everyone who was below it's pre-impact position moved upward toward it or
even above it.

Perhaps she retained her transverse stability by reason of the even, progressive nature of the flooding sequence. i.e she was initially punctured on one side forward of the centre of floatation. Flood water quickly spread for the entire width before rising and moving aft.
Although there were transverse WT bulkheads; there was little or no effective longitudinal division in the areas initially inundated so any final list would be retained throughout the sinking process.

Charlie, you might try and get hold of the plans and operating manual used for sinking and and raising heavy lift submersible ships such as the 'Mighty Servant' series. I used to have contacts in the business but they, like me have gone to the 'breakers yard'. Perhaps you still have contacts in academia?
I had an old friend named Bob Enstice who used to live in New Orleans. He ate, slept and dreamed this subject (was N. Architect and used to be with MIT then US Salvage). I lost contact with him. Last I heard of him he had an interest in the Stern Wheel Paddle Steamer preservation Society.

I worked with him when he was with J.K Tynan International of New orleans. He would be a very useful contact as he had years of experience in the study of and practical application of very phenomenon we are considering here. Then again - perhaps you know him already?

I see where you're coming from with the 'weight added low'. Given the length of Titanic and the obvious height of her longitudinal centre of G -perhaps the longitudinal aspect of her stability combined with the flooding sequence greatly off-set any transverse stability problems?

Cheers!

Jim.
 
Mar 18, 2000
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Jim said:
"I recall an officer called on everyone on the boat deck to go to the starboard side to offset the port list. If so, and he thought it might work; what does this tell us about the condition of Titanic? How many people would be on the boat deck at that time - double the number that got away? if so then we are talking of upward of 1500 people."

Yes, this is what Lightoller said happened - that Wilde called for the movement.

I will quibble over the "1500 people" statement. Many of the people still on the ship at the time were still below deck, and would not have have heard Wilde's order. Even people on deck, many on the stern parts of the deck would be unlikely to hear. I would guess 300 to 400 people maximun to have gotten this order.

If the order was passed at all. I don't recall anyone other than Lightoller testified to it.
 
Mar 22, 2003
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Regarding this discussion about the list, I would recommend people access the British Inquiry transcripts for Wilding's testimony on day 19, and look at questions 20242-20251. See HERE.

As far as how many people to correct a list is concerned:

20932. Another reference occurs in the evidence to the effect of moving the people across the deck with the view of correcting the list. I think Mr. Lightoller told us about that; have you made any experiment to see what effect moving a number of people would have? - We have made an experiment to test the ship’s stability, and from that it is possible to calculate the effect.
20933. I think you have made the calculation? - Yes.
20934. Moving 800 people through 50 feet would right her 2 degrees? - About 2 degrees.
20935. (The Commissioner.) That is to say, it is negligible? - It would show quite perceptibly on the deck. You would think you were walking uphill on these very flat decks 2 degrees is about 1 in 28, and 1 in 28 on a road is quite an appreciable hill.

We can estimate the list to port during the loading of lifeboat #10 at about 10 degrees between the boat and the ship's rail by the gap reported and knowing the dimensions of the davits and the boat, a correction of only 2 degrees would really be insignificant even if you could find 800 people.
 
Aug 10, 2002
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Hello again:
The text I used in my classes is "Trim and Stability for the Ship's Officer" 3rd Ed. by LaDage & Van Gement, edited by Wm. George. If you have access to such, start reading on page 197, it is most informative.
Regarding my research, does anyone know if the double bottom tanks were empty of full of water? It would make a difference. If they were empty then there would be Intact Buoyancy, something to be reckoned with. If they were already full then no problem.
Regards, Charlie
 
Jul 9, 2000
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>>Regarding my research, does anyone know if the double bottom tanks were empty of full of water?<<

As far as I know, there is no surviving record either from the ship or entered into testimony. I would expect that the fresh water tanks would have been kept full, but all bets are off for anything else. I don't know if the potable water was replenished during the course of the voyage or not.
 

Jim Currie

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Afternoon Sam,

You wrote:

"We can estimate the list to port during the loading of lifeboat #10 at about 10 degrees between the boat and the ship's rail by the gap reported and knowing the dimensions of the davits and the boat, a correction of only 2 degrees would really be insignificant even if you could find 800 people."

I've read your work concerning the extent of the list based on the evidence. I wonder if Titanic had an appreciable 'tumble home'? If so, that would most definitely account for quite a bit of the gap between the side of a lifeboat an the side of the ship. Modern ships have little or no 'Tumble-home' i.e. the ship's sides are vertical or almost vertical. However, most ships were designed with the sides sloping inward toward the centre-line in the old days. For the 'un-tech', I attach the following:

tumblehome.bmp


Because of this, provision was made to bows(pull in)the life boat in against the ship's side using bowsing tackle. Such tackle was also used to bring the lifeboat's side closer to the ship's side when the ship had a list.

As for finding 800 people - I would not have thought that too difficult since all the men who had families would have been up there trying to make sure their loved ones got away. Was there nor an incident where men had to be physically held back?

Cheers,

Jim.
 
Mar 22, 2003
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Hi Charlie.

As far as the double bottom tanks being full, this is what Wilding assumed about that:

20038. And on this voyage do you suppose they were full or empty? - One or two of them would be full as she neared the end of the voyage.
20039. Full of fresh water? - All would be full of fresh water when she left, and then it would be gradually used during the voyage. You do not put salt water into the same tanks to preserve the same stability outside the ship, but you do put salt water into some of the salt water tanks.
20040. When you start on your voyage are these tanks full of fresh water? - I believe every tank was full, all of the fresh water tanks.

20299. What assumption have you proceeded upon when making these calculations as to the cargo in the ship? - There are quite a list of deductions. In the first place, it is assumed that 5 percent of the volume of the space flooded will be occupied by the structure of the ship, such as decks, and cabin bulkheads and partitions. That is the first general deduction. It was assumed in making those calculations that the double bottomed tanks were flooded as well as the ship’s hold. It was further assumed that in the cargo spaces about one-quarter of the volume of the space would be occupied by water-excluding materials.
[Permeability of 75%]
20300. About one-fourth? - About one-fourth.
20301. Can you tell me why you assume about one-fourth? It may be altogether wrong? - It was from a variety of considerations. We have never fully calculated it, but taking ordinary cargoes that are carried in ships of this type, it was the best estimate that we could make.
20302. At all events, you thought it a fair estimate to make for the purpose of testing the arrangements which you were making? - Yes, my Lord. I may say I believe it is rather more. It is usually assumed cargo will exclude rather more than that, but taking the very light cargoes - light in character in relation to their bulk - which are carried by these express steamers, it seemed wiser to take one-fourth, to be on the safe side.
20303. Are those the assumptions that you proceeded upon? - Those are the assumptions. If you go into the bunkers of course you must then assume something else for the coal. In the case of bunkers, it was assumed that about one-half of the space occupied by coal would be available for water coming in; that is that the bunker probably is not quite full. Of course water gets in between the lumps of coal.
20304. The cubic quantity of water would be half the cubic contents of the bunker? - Quite, my Lord.


Hi Jim.

There was no tumble home on Titanic. The sides were essentially vertical.
 
Aug 10, 2002
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Hello:
Not only was there no tumblehome, but Boat Deck & A Deck are wider than B Deck and below.
Thank you for the information on the double bottom tanks. I'm assuming the double bottom tanks held fresh water which was pumped up to the tank room on the Boat Deck, and from there gravity fed to end users. I believe salt water tanks would have been Fore Peak and After Peak Tanks. There are six tanks outboard of the Generator Flat, I assume these were for Feed Water. Please correct me if I'm wrong.
Regards,
Charlie
 

Jim Currie

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Afternoon Charlie & Sam,

Thanks for that. I was curious about tumblehome having previously had a look at some of the photographs showing the overhang you refer to Charlie.
The following is a link to one of father Browns photographs showing the port side of Titanic taken from a forward gangway and looking aft.
You can indeed see the overhang of the decks you referred to Charlie but there seems to be a distinct tumblehome of the hull shell plating. The lines of rivets and porthole seem to follow the line of a tumblehome. http://www.titanicphotographs.com/galleryB.asp?GalleryID=3&ID=216
If you look aft to the stern, you can see the hull form coming vertical as it joins the stern plating. The lighting on another image of Titanic alongside a dock also suggests a tumblehome covering that part of the hull where the sides are parallel.
These may of course be optical illusions. In any case, the overhanging boat deck would have taken care of that and the boats would have been well clear on reaching the water.
However the fact that they did not seem to have used tricing tackle or bowsing-in lines is curious considering they did use them on the emergency boats. There is a picture somewhere that shows them rigged.
There is also an illustration showing a chain device with a bracket which clipped over the lifeboat gunwale with the other end attached to a sort of crucafix bollard at each end of each boat on the boat deck - seemed a bit heavy for a gripe! Perhaps since these were quadrant davits and the angle of the arm could be stopped at any point- it was only necessary to wind the boat out to where it could be lowered with the inboard gunwale close to the ship's side then the chain and clamp located to hold the boat alongside while embarking people?

Here is a pic. you might find interesting. It shows the gap between the ship's side and an unrestrained life boat on a passenger ship.
Davits are different of course.
lifeboat_drill.jpg




Sam, I had a look at the work referred to by Michael. Excellent!
Seems to me that the sinking and heeling sequence would be greatly effected if there was much difference in the rate of flooding fore and aft of bulkhead D. There obviously was since three compartments were flooded forward of D.
Reference was made to the fireman's tunnel. I presume the WT door at the aft end of that tunnel was automatically activated from the bridge although I read somewhere there was water in the tunnel.

I think the list to starboard was caused initially when the area to starboard of the Firemen's Tunnel was flooded. The ship started to right herself when the water reached the top of the tunnel and began pouring over into the areas on the port side of the tunnel. During this time, the water aft of bulkhead D was spreading across the full width of the bunkers and piling up pressure on the non watertight transverse bulkheads.

When the water was level across the area between Bulkheads A to C, the ship started trimming seriously by the head. The water would rise more quickly and reach a point where it crossed over and started aft along 'Scotland Road' The list to port would start some time after that?

Charlie, what do you think of the idea that when the flood water reached the top of the tunnel and started pouring over, and more significantly, 'into' the areas on the port side of the tunnels between bulkheads A & B and B & C; these enclosed areas constituted 'tanks' and therefore limited free surface might be experienced while the 'tank' effect held good?
The old lessons about righting a list by first pumping into the 'low side' come to mind.

I don't have access to the text book you refer to. I used H.J Pursey's 'Merchant Ship Stabilty' whic was the standard text in the UK MN. I also used it's companion publication:
'Merchant Ship Construction' and also 'Ship Construction Sketches and Notes by Kemp & Young.
 
Aug 10, 2002
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Hello All:
Mike, thanks for the information on Sam's article. I have a copy of it, but it is buried under so much other material it will take an mole to find it.
Jim, I looked at the picture you mentioned, I don't see any tumble home, I think it is an optical illusion.
Jim, I do believe the Firemen's tunnel did create port and starboard tanks. The particular part of our stability book I mentioned was about damage stability, in particular Added Weight vs Lost Buoyancy.
Regards, Charlie
 
Jul 9, 2000
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>>Mike, thanks for the information on Sam's article. I have a copy of it, but it is buried under so much other material it will take an mole to find it.<<

That's the nice thing about having easy access to it on the 'net. If it's buried, you can still find it with the click of a mouse.

Sam has done some incredible research and his illustrations are a first rate way of showing the consequences of some extremely complex subject that the non-technically inclined can readily understand.

>>I think the list to starboard was caused initially when the area to starboard of the Firemen's Tunnel was flooded. The ship started to right herself when the water reached the top of the tunnel and began pouring over into the areas on the port side of the tunnel.<<

Jim, some of our group (The Scotland Road Irregulars) had come to much the same conclusion several years ago, but with the caveat that flooding in the Fireman's tunnel may have played a role in evening things out.
 

Jim Currie

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Thanks Michael; I wondered about that.

I understand there was a WT door at the aft. end of the tunnel. I did read somewhere about the tunnel being flooded or at least some water having been in it.

Can't see what contribution to the list -if any- additional water in the tunnel would have made.

Since the tunnel was on the centre-line and forward of the centre of floatation, the addition or presence of water there would only have the effect of either increasing the ship's displacement (sinking the ship bodily) and increasing the draft forward or: reducing buoyancy and displacement while at the same time, increasing the forward draft.

If the end of the tunnel was sealed. The tunnel would then have become - in effect- a tank on the centre-line of the ship.

Buoyancy would be lost if the tunnel was effectively open to the sea. Displacement would also be reduced by the volume of the internal part of the ship open to the sea.

Ah! Charlie; old eyes are ever deceiving - thank the Lord for a good memory!

The book I have does not have a specific section dealing with damage control. Rather, it deals with the breaching of the hull as a completely separate subject. It's headings for the subject are: 'The Effect of Bilging a Compartment' - 'Increase of Draft Due to Bilging a Compartment'.
here's a copy of the relevant pages. Forgive my poor photography skills:
buoyancy_005.jpg


buoyancy_007.jpg


You will probably have to increase the magnification to read these.

Obviously, knowledge of other factors contribute to the solution of a particular problem.

Cheers,

Jim.
 
Jul 9, 2000
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>>Can't see what contribution to the list -if any- additional water in the tunnel would have made.<<

We didn't think it would have. In fact, one of us...Captain Dave if I recall...mooted the opinion that it would have been the opposite. Don't trust my memory on the source.

>>Buoyancy would be lost if the tunnel was effectively open to the sea.<<

We do know that flooding was observed in the Fireman's tunnel. The man who testified to that indicated that he saw it by looking down the spiral staircase. Frankly, I have some reasons to be skeptical of the asserted vantage point, but the end result here is what matters. What we don't know with certainty is whether or not the Fireman's tunnel was in direct and open communication with the sea. I know of one individual...Bruce Beveridge if I recall correctly...who suggested that this could have been a consequence of damage to one of the tanks.

There's no way to back that up short of getting an ROV down in there for a look, but I would be reluctant to be against him.

Considering the forces at work up forward, I wouldn't be surprised by anything. Factor in the bending and racking and it's not hard to see that some rivets and seams could have failed.
 
Mar 22, 2003
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As Jim said, flooding in the firemen's tunnel would NOT have contributed to the list since it was on the ship's centerline. The flooding was observed by leading fireman Hendrickson just a few minutes following the collision. He was looking down the port side staircase after coming out of his quarters again on G deck. It was leading fireman Thomas Ford who told him about it.

Hendrickson said the water was streaming in from the starboard side but did not see exactly where the source came from. He then left there and went to report it. When he arrived aft on E deck on his way to the engine room, he met up with 2/E Hesketh who told him to get some lamps to take down to the stokeholds, as the lights were out down there at that time.
 
Jul 9, 2000
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>>As Jim said, flooding in the firemen's tunnel would NOT have contributed to the list since it was on the ship's centerline.<<

As I indicated, we didn't think it would have. Quite the opposite. In fact, I think Captain Dave expressed a belief that it may have prevented the ship from rolling over at a critical moment. (That much might have been overstating the case.)

>>Hendrickson said the water was streaming in from the starboard side but did not see exactly where the source came from.<<

I'm a bit mystified that Hendrickson saw much of anything from his stated vantage point. The overlap of the stairs would have effectively blocked his view of the tunnel. I've seen photos of a similar staircase taken from inside the wreck of the Britannic and there isn't that much of a gap for looking down the side.
 
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