Welome To The Titanic Tech Thread

Dec 2, 2000
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>>which to me means that Mr. Mengot is of the opinion that the ship was going to sink no matter what, irregardless of the ships watertight doors and bulkheads.<<

For whatever it's worth, it's a position I'm as inclined to agree with as you are. By the time any damage assessment was done, they knew that the extant of the damage included everything back to Boiler Room Six with ingress into BR#5. The damage going back to BR#6 was non-survivable in and of itself, and Andrews was well aware of this. So was Wilding. 4 sections flooded and you still float. 5 or more and you're going swimming. It was only a question of when.

The rest is haggling over the details but I find the details fascinating. Given the possible structural damage caused by a grounding, I have to wonder if even four sections flooded would have ultimately been survivable and if so, for how long. (The notorious "What If's" rear their heads here!)

It's a pity we can't whistle up the same team at Gibbs and Cox which ran the finate point stress analysis, and perhaps working in the potential consequences of damage to the internal framing.
 

Roy Mengot

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May 16, 2006
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I've given up on even using the term 'grounding' and so has pretty much the whole MFP. There's no evidence of grounding aft of #3 Hold and anything forward of that becomes semantics. The hull is so rounded, what's bottom and what's sides? The damage was there somewhere and it's still in the 12 sq ft range. Hitting the shelf versus the rising edge of the berg is largely academic.

The Gibbs & Cox finite element analysis is being revisited, but only in terms of taking a skeptical look at the expansion joint hot spot. That may well have simply been an error in how the ship was described to the simulator. The pull and compression forces from the simulation are being reexamined in the context of a possible bottom-up break. Other stresses well forward on the ship are considered non-contributors to the ultimate time line.

Regards
Roy Mengot
 
Dec 4, 2000
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In response to what Roy said about how the MFP views the grounding...I would have to say that the vicious personal attack when I presented the paper proved to me that the MFP never even considered it--and, therefore it cannot be said that it has been "given up."

There was one person in the room who treated my presentation with respect and who asked serious questions. That was Roy Mengot. He was a beacon of civility in an ad hominem attack. For this I will be eternally grateful. And, if Roy chooses to discard the grounding theory I will honor his choice with the same respect he gave me. Let it never be said that we are locked in combat over this issue.

Still, I have to rise in defense of the grounding argument for the nature of the accident.

The disagreement between a "grounding" and whatever sideswipe might be suggested is something that illustrates the differences between real world experience and theoretical constructs.

The impulse-and-rebound description favored by the MFP requires Titanic to have maneuvered in a way that no actual vessel steered by a rudder could ever have done. The reason is the outward swing of the stern during a turn. Working knowledge of this important detail of shiphandling is something necessary for docking, but is not usually critical to the naval architect's job of designing ships. (Nor are most of the naval architect's formulae part of a captian's education. Different disciplines.)

The conventional version of events is totally fraudulent in the sense that it is a physical impossibility. To repeat myself ad nauseum, for Titanic to have sideswiped the bow during a left turn...the conventional view of events...would have caused the outward swing of the stern to force the whole side of the ship into contact with the berg. That did not happen.

Some 37 seconds into a hard-over left turn (the "hard-astarboard of the conventional story) Titanic should have been heeling outward to starboard just as all large ships lean to the outside of sharp, fast turns. However, the historical record is quite clear that the opposite took place--the ship lifted to port.

The conventional impulse-and-rebound sideswipe theory fails to take into account the mechanism by which the starboard side was lifted during impact. This lifting was clearly described by lookout Lee and corroborated by Fleet. As far as I know, a sideswipe would not have caused lifting, but running over an underwater extension of the berg would have.

Something else, the conventional theory views the iceberg as an object as fixed in the ocean as a continent and made of something harder than diamonds. In fact, the berg was floating ice and only 1/10th as strong as steel. Myopic focus on Titanic prevents looking at the larger view of all the damage done during the accident. Quite simply, if Titanic's steel was opened to the sea there must have been some pretty substantial destruction of the berg.

Ice in 42 North latitude is undergoing rapid disintegration. If it did not, the whole Atlantic would be an iceberg playground all year. So, it is only reasonable to assume that Titanic's iceberg was also experiencing it's natural process of decay. If the ship had hoisted itself on an underwater projection of the berg, it is quite reasonable to ask, "Was the ice strong enough to support that weight of steel?"

Adding to all of this are the experiences of real ships. We have several good descriptions of vessels running over underwater extensions of icebergs. In fact, the danger of such an accident is sufficiently great that as early as 1909 mariners were being advised to give bergs a wide berth to avoid "grounding" on the ice hidden below the surface. I have not yet found another accident involving a bow-only sideswipe of an iceberg.

Finally, I have run aground both by accident and quite deliberately. And, I've had some impulse-and-rebound sideswipes of solid objects against the bow. My personal, real-world, not hypothetical experience tells me that the survivors who described Titanic's accident were speaking of a grounding and not a sideswipe.

The nature of a grounding, and the subsequent damage to the iceberg, produces quite a different dynamic for the first 30 minutes of Titanic's sinking. From my point of view, the grounding theory calls into question most of the conventional views about the size of the damage, its location, and the amount of flooding. It raises other questions about the physical design of the ship. All of these questions raise doubts about the accuracy of the thousands of words published "explaining" the sinking. Bluntly, I believe most objectors to the grounding theory are motivated by fear that they may have been wrong in their interpretations of events.

Outside of this thread, I know that Roy is currently beginning a new assault on the whole topic of how Titanic came apart. He and I undoubtedly have differing views on many issues. However, from what I can see he is starting with clean paper and a fresh point of view. I don't want to get into a protracted discussion over this old stuff while he is doing this new work. That would just get in his way and prove nothing. So, I suggest both of us have had our say on this subject. Now, we need to look forward to what's coming next. If Roy continues his usual good work I suggest we should stand by for some surprises.

-- David G. Brown
 

Roy Mengot

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The MFP members I talked with mainly discount keel damage aft of the noted side damage in #6 BR. The TV show made a big deal about it and then said it never happened. The MFP concurs. Damage forward of that probably was a combination of hitting the shelf of the berg lower and then rising up the side as the ship widened into the body of the berg. I've heard little to no argument against that. Is that grounding? Currently, based largely on the TV show, grounding has to do with keel damage near the area of the break-up. That is not what David originally was talking about at his presentation for the MFP (I was there in D.C. that day). The popular definition of grounding has mutated.

I have most of another paper put together that I'll post soon on the TRMA webpage asserting that the water seen in the fireman's tunnel in the early minutes was not flooding as a direct result of damage in the first 5 minutes as listed in the BoT inquery conclusions, but was overflow of the #1 hatch at G-deck some 15-20 minutes later. Between a timeline of Hendrickson's movements and writings by leading fireman Threfall, the first appearance of water in the firemen's passage occurs right about when Wilding and Bedford/Hackett say water should overflow from #1 hatch at G-deck. Where was the actual damage? Beats me. Down there somewhere.

Regards
Roy Mengot
 
Dec 6, 2000
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Roy - I hope you'll post here, when your paper is available on the TRMA webpage. I'm sure many of us here would like to read it.
 
Dec 2, 2000
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>>Hitting the shelf versus the rising edge of the berg is largely academic. <<

Perhaps, but I don't think the possibility of a grounding/allision event and it's possible impact on the structural integrity of the hull can be safely dismissed either. The underwater portion of the berg is every bit as irregular as what was exposed above. It may not have resulted in through hull damage to the inner hull, but any damage/distortion to the framing would have had some impact. If not on the breakup of the ship, then surely on whether or not she could have been economically repaired had the Titanic survived.

>>it is quite reasonable to ask, "Was the ice strong enough to support that weight of steel?" <<

Unless it was a truly massive piece, I doubt it. I would think that the Titanic would have abraded away whatever she came into contact with.

Something else I think we need to take a look at is the structural strength of the ship herself. David has observed on several occasions that while the sheer size of ships increased (Which it did) that strength did not increase in proportion to the size of the vessel and I'm wondering if this may not have played a far more significant role...at least in the break up...the previously considered.

Dave Gittins mentioned something about that and what the BOT may have known about that in his e-book. Since I have a copy, I'm going to start going over it to see what he has to say on the matter.

Of course I may just be smoking dope in my own personal take on the matter. The basics as Roy outlined don't go away. Whatever happened (Or didn't happen) to the double bottom, there was still enough through hull damage to the inner hull and excessive stresses on the hull girder to send the Titanic to the bottom of the Atlantic in a shower of steel. The dynamics of that are interesting fodder for investigation in it's own right.

>>Roy - I hope you'll post here, when your paper is available on the TRMA webpage. I'm sure many of us here would like to read it.<<

Count me in.

FWIW, I recall that Bruce Beveridge suggested that it may have been the fresh water tank over the tunnel that may have been responsible. He may be on to something but I'm more then a bit skeptical of that. For one thing, it doesn't look to me like that tank is even close to being large enough to flood the Fireman's tunnel.
 
Dec 4, 2000
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Two things-- First, Parks and I picked the word "grounding" for our paper because it is the easiest way to give an overall picture of what we believe happened. In reality, it would better be described as a "touch-and-go" event. However, that phrase has entered everyday speech and lost most of its nautical connotations.

I do not know where anyone got the idea that a ship would "ground" on its entire length. The only time that I've seen it happen is during a storm when a hull washes sideways onto shore through the enormous force of moving water. In any self-propelled grounding that I've found in the historical record the damage is always confined to a portion of the hull. The guys at the History Channel misunderstood our concept of the event and have admitted so to me.

To me, the big question is this: "How can damage rise along the side of the ship (the openings allegedly being higher above the turn of the bilge) when the ship lifted to port?" The lifting of the starboard side means that something was acting underneath the starboard bilge, particularly in way of hold #3. If the ship were rubbing against a spur of ice, this lifting would have caused the damage to move downward on the side of the ship, closer to the turn of the bilge--quite the opposite to what is claimed. The lifting of the ship would have forced damage from scraping along a spur of ice to move downward, not upward.

In keeping with the vast historic record of self-propelled groundings, Titanic's ended while hold #3 was on the ice. This is easily proven by quartermaster Olliver's U.S. testimony. He was on the bridge, but in a position where he could not see the iceberg until it passed the starboard bridge wing. Olliver noted with specificity that the "rumbling" of the ship over the ice ended before the berg came into his field of view. Looking at the plan of the ship, it is obvious that Olliver's testimony forces the end of contact to have been ahead of bulkhead D within hold #3. Whatever did or did not take place aft of bulkhead D was not part of the hard contact with the iceberg.

As to the flooding of the ship, I have grave reservations about the conventional version, but gravest with regard to the first 30 minutes. Whether deliberately, or by lack of aggressive research, the BOT report managed to condense the first 30 minutes into a 10 minute time span. Judging the motivations of men now departed is a dicey task. However, it would seem that this condensation of time is related to the failure of the BOT hearing to explore and report the fact that Titanic resumed steaming during those "missing minutes."

The flooding of the tunnel seems to have been discovered by the 12-to-4 stokers starting to move to their stations. One of the leading stokers, Hendrickson, survived to describe what he saw. His description of water tumbling along the starboard side of the tunnel could only have taken place during the early moments of flooding. If the tunnel were full, he would have described water rising up the circular stairway. Also, the construction of the stairway meant that to see water moving in the tunnel he had to be nearly down on the deck of that structure. Hendrickson could not have made his observations from a deck or two higher in the ship. All of this points to the tunnel beginning to fill at about the time of the midnight change of watch--fully 20 minutes after contact with the iceberg.

Wilding's famous prediction of the ship sinking in "an hour to an hour and a quarter" after water reached the top of bulkhead D came during the BOT hearings. At both the BOT and New York limitation of liability hearings Wilding said that would have obtained at about 40 minutes after impact. Added together, Wilding's times appear to have "sunk" the ship far too early:

11:40 + 40 min = 12:20 a.m.
12:20 a.m. + 1:15 min = 1:35 a.m.

However, this is not the case. Wilding's 40 minutes did not really start at impact, but at midnight about 20 minutes after the iceberg. Adding these minutes into his prediction gives a very significant time:

1:35 a.m. + 20 min = 1:55 a.m.

Using the pocket timepieces stopped by salt water immersion, it is possible to place the breakup of the ship very nearly at 1:55 a.m. To my way of thinking this proves that Wilding not only knew about the breakup of the hull, but used it as the "end" of Titanic as a ship. He was also aware that his "40 minute" condition was really the state of the ship nearly an hour after the iceberg. But, then, Wilding was not an unbiased scientist studying the sinking. His job was to protect the interests of his employer, Harland & Wolff.

(Note: In the above Wilding discussion a straight-line time is used starting at 11:40 p.m. The stopped pocket watches showed other times because of being set to any of several alternative time references. When reduced to a single reference, the time of the breakup occurred between 1:50 and 1:58 a.m. Wilding's 1:55 a.m. falls neatly in the middle of that range.)

-- David G. Brown
 

Roy Mengot

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From Mike's post:

>> FWIW, I recall that Bruce Beveridge suggested that it may have been the fresh water tank over the tunnel that may have been responsible. <<

Bruce has backed away from that. After a flurry of email, he agrees the water in the firemaen's passage was overflow from #1 hold at G-deck.

>> David has observed on several occasions that while the sheer size of ships increased (Which it did) that strength did not increase in proportion to the size of the vessel and I'm wondering if this may not have played a far more significant role...at least in the break up...the previously considered. <<

Actually, overall strength of the effective girder of the ship did increase. Basic thickness of the hull and it's ribs did not. It still hasn't on the larger cruise ships. Overall strength of the upper shear strake was increased to counter-act tensile stress in a hogging situation. Even so, Olympic saw strain and cracks later in its career. The O class liners were retrofitted with reenforcement where the shell plate meets the tank top, after a severe 1911 storm showed stress in Olympic. Those upgrades were only in the area 1/4 of the way in from the ends and nothing was deemed needed in the center.

Regards
Roy Mengot
 

Roy Mengot

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On David's post:

>> To me, the big question is this: "How can damage rise along the side of the ship (the openings allegedly being higher above the turn of the bilge) when the ship lifted to port?" The lifting of the starboard side means that something was acting underneath the starboard bilge, particularly in way of hold #3. <<

An initial impact near the prow, down low on the ice shelf, happens where the ship is 30' wide. As the ship widens to 90 feet, progressively more of the berg arcing up to the water line and above is sheared off. The ship may have been shaving off the berg over a 30' vertical profile of the hull but only suffered damage where something particularly dense occurred in the berg. Possibly boulders. The slight rise on the starboard side is a fraction of the possible contact surface.

>> Using the pocket timepieces stopped by salt water immersion, it is possible to place the breakup of the ship very nearly at 1:55 a.m. To my way of thinking this proves that Wilding not only knew about the breakup of the hull, but used it as the "end" of Titanic as a ship. <<

Wilding only knew that Titanic would go unstable. It would founder. What form that would take was of no interest to him. Break-up. Roll over. Tip-up. Whatever. It stops floating up-right. That's all he knew. The ship was not designed to sink gracefully. But the mathematics of damage stability gave him a pretty good idea of when it was likely to happen.

Regards
Roy Mengot
 

Erik Wood

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Apr 10, 2001
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Because I again find myself in position to comment on what has been written by all, I forewarn you that this is going to be long, boring and probably ignored. But my intent is only to stir conversation, because from what I have read since my last post, it is slowly (far more slowly then I would have liked) heading in the direction in which I wanted it to go.

As an aside I am going to reference posts by date and time so that others may refer to them.

The next few quotes and responses are from Roy's post of 29 June at 6:57PM:

They already knew the bulkheads would be topped. 4 is good. 6 is bad. At the magic number X, the ship would tip or roll because it didn't want to float upright anymore. Anything else about the ship's design was irrelevant.
First I don't think Roy intended it this way, but I took it as a lesson that any mariner should already know. I am by no means even close to half way being something resembling a naval arch. But what is discussing is basic knowledge, especially when it comes to loading cargo. The difference being, that cargo the ship is designed to hold, water...or extra water....not so much.

But the red and underlined portion stills has me asking questions. While agree that eventually the ship will roll extra, and while I further somewhat agree about water over topping the bulkheads I still don't understand the full intent of that phrase.

I will go out on a ledge and say that I agree with it, but not for the reasons that Roy posted it (I don't think). In my view we are disagreeing on the details but agreeing on the outcome for the most part.

Next quote:

Tom was not concerned about the list.
The rest of the paragraph from which the above was taken I for the most part agree. But I strongly disagree with the above.

I agree that he may not have been concerned from a stability standpoint based on his primitive math, but he was concerned about it, because I am willing to bet my next pay check that Smith was.

Smith is concerned with lowering boats safely. To do that, he needs a stable platform in which to accomplish it. If Smith is concerned (even if they are unfounded) he will let Andrews know his concerns. This is the view of a fellow captain.

To me that was to much of a blanket statement. I disagree with the fact the was not concerned about. Why is open for debate.

I am not picking on Roy (Dave is about to get some time in a minute), but this next series of quotes is from his post 30 June at 3:17pm.

I've given up on even using the term 'grounding' and so has pretty much the whole MFP.
I would have to agree. I have NEVER fully agreed with the term "grounding". Dave Brown and I have haggled over it for the last 4 years. It is both (in my view) the improper nautical term, and does not fully describe the manner in which the ship made contact. I am not sure that there is a current word or phrase that does describe what occured (or what I believe occured). I use it now because I am tired to explaining my position on why I disagree with it.

I would say that it is possible that damage, like that caused by a grounding, but not exactly caused by a grounding could have been found forward of hold 3 as well as aft of it.

A grounding can cause damage in more then just the area that made contact. That is part of the reason for this thread in the location that it is in. If you will all recall Mark Chirnside was kind enough to provide me with a large volume of information regarding the grounding of the Aquatania in the Mersey Side after the 1st World War.

Information from the BOT showed that the she was plagued with problems in key areas (oddly enough many of those areas that have been discussed in relation to Titanic) and discussed in this thread.

But the Aquatania was actually grounded, she was making way and was stopped by grounding. The same can not be said for Titanic. Therefore the damage caused is different or should be different.

Again from Roy's post:

Hitting the shelf versus the rising edge of the berg is largely academic.
I am not sure I understand that. To me it says that that whether the ship hit the shelf vs. grounding, or performing a touch and go on it makes no difference. If that is the intent...I disagree.

A quick view of www.ntsb.gov (which I am first to admit are not all that thorough) will show that there is a vast difference in relation to the maneuver the ship performs and it's reaction to it both prior to and directly after contact in whatever form. Not to mention the fact the to some degree the type of stress in relation to contact and water ingress will be different.

Now the following series of quotes belong to David Brown's post of 30 June at 7:05pm.

The impulse-and-rebound description favored by the MFP requires Titanic to have maneuvered in a way that no actual vessel steered by a rudder could ever have done. The reason is the outward swing of the stern during a turn. Working knowledge of this important detail of shiphandling is something necessary for docking, but is not usually critical to the naval architect's job of designing ships. (Nor are most of the naval architect's formulae part of a captian's education. Different disciplines.)
The part in red is critical to understanding the discussion going on between Roy and I. I have never met a Naval Architect that liked me. Mainly because most of them have made the mistake of telling me that a ship "can not" do something, or "will not" act in a certain way and I have pleasure of telling them that my at sea experience tells a different story. With the addition of the "black box" to certain ships I have mathmatical and computer added proof of my assertions. I am not, nor have I have been or claimed to be an expert on ship design and shipbuilding. I am however somewhat of an expert in the area of shiphandling.

I can confirm that large ships, those in excess of 500 feet (the only ships I have any experience conning) will not and can not act in the way suggested in the traditional or conventional wisdom. In Titanic's case it is not only a physical impossibility, but would have required a highly incompetent man at the conn.

For the purpose of being difficult I am going to attach several pictures. These ships are manuevering in the ever tight Cuyahoga River in Cleveland and are perfect examples of the stern swing that David is discussing here. They are posted here with the permission of www.boatnerd.com. I post these to prove my point:

The first is a series of pictures of the M/V Earl Oglebay in the Cuyahoga river...note the position of the ship (not using the thruster) to swing around. The position of the stern vs. the bow and landscape around it: View Image View Image

In those pictures you can see the swing and nature of the turn with power going ahead.

Given what I described the next pictures further illustrate my point. In one you can see the ship using only one engine to control and maintain position to manuever around: View Image View Image

I hope that this illustrates my point regarding Titanic. Ships do not and can not handle in manner in which some describe nor as the conventional wisdom suggested describe. It is physical impossibility.

Another quote from David's post:

Some 37 seconds into a hard-over left turn (the "hard-astarboard of the conventional story) Titanic should have been heeling outward to starboard just as all large ships lean to the outside of sharp, fast turns. However, the historical record is quite clear that the opposite took place--the ship lifted to port.
While the testimony that David is referencing in this paragraph is that of Fleet and Lee it does not address the rest of there testimony. Specifically that in reguards to the position the ship took as it approached the berg. In my view this testimony points against a "grounding" type incident and leans towards more of a allision. The shift to port as discussed proves nothing, other then the ship was in contact with the ice at some level, and if you take only that testimony and ignore the rest (to include the nature of the way the ship sank) this would seem to agree with the conventional set of events. The ship "could" lean to port as the ship made contact while turning to port (the hard astarboard order in the conventional story). It's degree would be somewhat negated. But it could happen.

Again back to Roy's post on 30 June at 9:37pm.

I have most of another paper put together that I'll post soon on the TRMA webpage asserting that the water seen in the fireman's tunnel in the early minutes was not flooding as a direct result of damage in the first 5 minutes as listed in the BoT inquery conclusions, but was overflow of the #1 hatch at G-deck some 15-20 minutes later.
First and somewhat off topic, I hope that we can talk Roy into presenting that paper in Toledo and discussing it at length. I think we would all get a much better understanding of what he is talking about.

In regards to the Firemen's tunnel.

If I recall rightly this topic was discussed in Topeka. The discussion regarding the tunnel was somewhat light. But I am interested to read about it now. The G deck overflow into the tunnel in the first half of an hour echoes something Roy said in Topeka some 5 years ago. I am anxious to read it.

Again from Roy's post:

The popular definition of grounding has mutated.
As noted above I agree and that is why I disagree with it's use in the manner that David is suggesting. The two of us have come to an understanding....but I favor allision and even that isn't the proper term.

The following and the thankfully that last quote is the exchange between Michael and Roy and was taken from Roy's post on 1 July at 4:55pm.

>> David has observed on several occasions that while the sheer size of ships increased (Which it did) that strength did not increase in proportion to the size of the vessel and I'm wondering if this may not have played a far more significant role...at least in the break up...the previously considered. <<

Actually, overall strength of the effective girder of the ship did increase. Basic thickness of the hull and it's ribs did not. It still hasn't on the larger cruise ships. Overall strength of the upper shear strake was increased to counter-act tensile stress in a hogging situation. Even so, Olympic saw strain and cracks later in its career. The O class liners were retrofitted with reenforcement where the shell plate meets the tank top, after a severe 1911 storm showed stress in Olympic. Those upgrades were only in the area 1/4 of the way in from the ends and nothing was deemed needed in the center.
I think that Michael (and I am not speaking on behalf of David) misunderstood the intent of that discussion. David and I have both discussed how as ships grew in the first part the century the bigger they got damage appeared in almost the same location in all the big 4 stackers. Oddly enough Titanic, Britannic, and Lusitania all sank with damage in the forward third of the vessel. The latter two by different means of course and with different circumstances to follow.

My point in the discussion was that there was a odd similarity in the manner some of the first "big ships" problems in there career and in addition that Titanic may or could possibly be included in that bunch.

The points on hogging are noted...
 

Roy Mengot

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May 16, 2006
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To Eric's post: (I need to learn to do the nice quotes:

>> Again from Roy's post:

-----------------------------------------------------------------------------
quote:
Hitting the shelf versus the rising edge of the berg is largely academic.

--------------------------------------------------------------------------------

I am not sure I understand that. To me it says that that whether the ship hit the shelf vs. grounding, or performing a touch and go on it makes no difference. If that is the intent...I disagree. <<

This and the other quote about the damage location being academic get me back to basics of damage stability of a ship. If you push a book slowly toward the end of a table, I can calculate the point where the book will reach a balance point and fall off. If the book is open and face down going through spilled coffee and sharp edges that damage the book, that only matters if it changes the rate the book is moving toward the table edge. For Tom Andrews, the initial inflow rate was all that was important. The distribution of the holes told him that his "book would reach the end of the table". Bent fittings, jammed doors, leaks in the bukheads might have mattered if Titanic could have been saved but the distribution of holes alone defeated his bulkhead defenses. On Lusitaninia and Brittanic, in both cases, the sudden list caused lower portholes that were open for ventilation to be submerged, thus again defeating the bulkheading system.

I say again, if the holes were 3 feet from the keel, 5, 10, 25 feet up the hull, or any combination, it doesn't matter. Collateral structural damage doesn't matter. The distribution across too many compartments is all that counts. From there, you don't worry about the repair costs or ship's handling. It stopped. You just worry about how fast that book is being pushed to the end of the table. I have a number on the back of an envelope that I calculated that says we're going over the edge.

Find a lifeboat seat.

Regards
Roy Mengot
 

Erik Wood

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I for once think I understand the meat of what Roy is suggesting. If I am wrong....I apologize to Roy.

The distribution across too many compartments is all that counts.
This goes back to a question that I had posted not all that long ago on this thread.

That quote again means to me that the water intake caused by contact is the sole reason for the sinking, because it is spread out so far.

If this is the true nature what is being said, then perhaps we should shift discussion to the flooding patterns and the intial rate of flooding in the first 5 compartments (not to include the forepeak).

Do we agree??

On the lighter side:

Me and lifeboats......don't get along so much.
 

Roy Mengot

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May 16, 2006
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>> That quote again means to me that the water intake caused by contact is the sole reason for the sinking, because it is spread out so far.<<

Bingo! If the water inflow had been slower (smaller holes) the ship would have lasted longer but still would have sunk. When water inflow reaches the magic number X, the ship doesn't want to float upright. That's what damage stability is all about. At 30-35kt tons of flooding, Titanic doesn't want to float upright.

The primary defense for a naval architect to prevent water inflow from reaching point X and driving the GM/GZ curve negative is either in the spacing of the bulkheads or the resistance of the hull to damage. Titanic's bulkheads were meant to resist a head-on or side collision with another ship. The hull was single ply shell plate so a collision would produce water inflow. 2 flooded compartments anywhere or flooding the front 4 prevents the ship from reaching point X.

The freak occurrence of ice breaching 6 compartments was enough(4 compartments aft of #1 hold was enough to guarantee disaster). This is what Andrews and Wilding were thinking. It's formulaic for them. Breach that many compartments, at any water flow rate, and the ship will founder. It's only a question of time.

Andrews could calculate the time to point X in real time during his initial survey. Wilding deduced it from the attitude of the ship based on testimony. Neither needed to consider any ancillary structural damage to the ship as a result of the collision.

I'll look at putting together a primer on damage stability for the meeting this fall. I got the basics from Chris Hackett and the details from a 1905 naval architecture textbook. It's clear to me that Andrews and Wilding knew their stuff.

Regards
Roy Mengot
 
Dec 2, 2000
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>>I'll look at putting together a primer on damage stability for the meeting this fall.<<

Perhaps you can find ways to explain the terminology and the mathamatics in a way that the non-mathamatically inclined can understand. I think I can help with a couple of articles I found while poking around This Website:

Understanding Block Coefficients at http://www.navweaps.com/index_tech/tech-015.htm

Metecentric Hight at http://www.navweaps.com/index_tech/tech-009.htm

Understanding the Prismatic Coeefficient at http://www.navweaps.com/index_tech/tech-004.htm

That should do for a start. I'll try to find some more as my decidely strange work schedual allows.
 

Roy Mengot

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May 16, 2006
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You don't need all that much mathematics to picture what's happening. If the center of gravity (greatest mass of weight) is low, then buoyancy pushes up from the bottom and water pressure to the sides holds the ship steady. The GM/GZ curves are very positive.

After water intake, the center of gravity rises. If there is a list, then the side and bottom pressure want to push the ship over to a roll. The GM/GZ curves are flattening out. The side and bottom pressure are called righting levers.

Too much list and side pressure turns into lift buoyancy and the original lift buoyancy turns into side pressure. The ship rolls and does it quickly. The GM/GZ curves went negative.

That's for a cross section view of the ship. Lengthwise stability is more difficult to visualize but works the same way. If the ship is too heavy at one end, then at point X, it want's to float vertically instead of horizontally, which is not a good thing. The force of buoyancy suddenly works against keeping the ship afloat upright. That happened about 2am.

The whole book "Titanic at 2" is about the sudden changes in the ship and everyone's perceptions about what was happening. The GM/GZ curves went negative. 2 and half hours to tip 9 degrees, 10 minutes to tip 70 more, had it not broken.

Andrews did the math in the design and applied the math after the collision. By midnight, he knew. What happened at 2am was no surprise to him.

Regards
Roy Mengot
 

Erik Wood

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Apr 10, 2001
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I do not have the time to do it now...but I will I think we are on the road to something. I will do my best to get something posted by next week.
 
Dec 2, 2000
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Just a note to all participants, for some reason, the threads here don't default to any sort of archive so it may be a good idea to start seperate threads to discuss any and all different ideas and theories.

That way, we don't end up with threads so long that we have to come back in another life to see the whole thing download.
 
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Roy mentions two critical values, one is a rate of flooding, and the other is the ~35kt of water which causes Titanic's curves to go negative. I understand what Roy is saying, but I'm having trouble with his suggestion that these two values were beyond influence by either the ship itself, or the people aboard her. Up until now, I had thought both of these figures were in fact very much influenced by both ship and men. Is this now not the case?

Allow me to rephrase again for clarity:
The discussion regarding the flooding of BR6 hinges on the idea that if BR6 is kept from flooding by the pumps, then both rate of flooding, and critical flooding volumes are checked, albeit by a hair's width margin.
Are we now saying with complete confidence that the flooding of BR6 was irrelevant to the survival of the ship?

Or the discussion of the ship's structural integrity after the initial impact event. For several years now we have vollyed around the notion that the ship's forward structural members were deformed in some way by the impact, and afterward suffered aggravated deformation as the forward sections flooded. This continuing deformation causing new gaps and separations in the hull and bottom, and allowing water to enter areas undamaged by the initial impact event. This aggravated failure is thought to be important because it allows the rate of flooding to increase, and allows the volume of flooding to exceed the critical amount mentioned by Roy. But are we now saying that these failure modes do not truly affect either the ship's stability, nor its longevity on the surface as an inhabitable vessel??

I thought the whole paradox of Titanic was that it was damaged by ice in such a unique way that the flooding was just enough to barely exceed the deadly X values which could sink the ship. And that if the people on board had somehow known this fact, that they may have taken different actions which could have extended her life on the surface until rescue vessels could arrive along with daylight.

I'm truly confused about this now. Mostly because of all Titanic researchers, I confess to admiring Roy's work most of all. So here is my most trusted expert on the ship and the sinking to my mind saying that in fact from the moment the iceberg cleared the stern rail, all the variable for all the functions were filled in, and all that was left was for the math to crunch itself down to its final outcome; which unfortunately had a negative sign out front of it. Roy,... say it ain't so.

BTW: Roy, its very good to see your posts again on ET. If you are still living in Texas, I feel for you given the blast furnace summer they've had this year. My folks have lived there for 80+ years and they haven't seen a summer this bad in 25 years. Thank the Lord for A/C!!

Yuri
 

Roy Mengot

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May 16, 2006
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Yeah, it's hot here in Texas this year again.

>> So here is my most trusted expert on the ship and the sinking to my mind saying that in fact from the moment the iceberg cleared the stern rail, all the variable for all the functions were filled in, and all that was left was for the math to crunch itself down to its final outcome; which unfortunately had a negative sign out front of it. Roy,... say it ain't so. <<

'Tis so. The unique pattern of damage that breached too many compartments defeated the defenses Andrews built into the ship's design. The flooding rate was also 15kt per hour while the max pumping capacity, if all pumps were properly cross-coupled to damaged areas was 1.7kt per hour. Or 1/10th the flooding rate.

Any structural deformations caused by the collision (which I believe to be close to nil) take a back seat to new openings like portholes and even an E-deck gangway door that might have been left open. Even so, the flooding rate slows as the interior water level approaches the outside level. Andrews factored that in.

But he knew the pumps would never keep up with the flooding and the bulkheads would be topped.

An aeronautical engineer on a 747 doesn't need to worry about additional structural damage once a wing snaps off at 30,000 feet. It's only a matter of time at that point. And that's how certain Andrews was of Titanic's fate once he knew how many compartments were breached and the rate of water inflow. That's the best analogy I can think of.

Regards
Roy Mengot
 
May 9, 2001
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Well then if the rate of flooding determined everything about the sinking, then was the rate of flooding constant from the time of impact? Or is there still room for speculation regarding the initial rate of flooding right after impact?