What caused the damage to the stern?


Mar 22, 2003
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You raise a good point here Dave. Since the stern went down after assuming a near vertical position, the pressure differential between the lowest portion and the highest would be head of about 300 ft. That's about 9 atmospheres differential pressure. And that difference would be true even after the ship went below the surface as it went straight down. But any trapped air would compress as water from the bottom moved up toward the top, and the differential would drop until equilibrium was achieved, or the top blows off. And, if my calculation is right, equilibrium would be achieved when the air compresses to about 1/3 its original volume, if nothing blows first like a hatch near the top.
 
Jul 9, 2000
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>>The closest I can come are the remarks in which the "booms" were attributed to boiler explosions. Anyone remember any better descriptions?<<

I seem to recall that sudden implosions of the air filled spaces such as the reefer units were themselves were credited with the noise. I don't remember the source, but it makes sense to me. Such an event would hardly have been mouse quiet.
 
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Alicia Coors

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Sam and Dave (did you ever sing together?
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),

I think that the hydrostatic head would be much less than 300 feet - for starters, the engine rooms would have flooded before even leaving the surface, and the spaces immediately aft very soon afterwards, "ice cube tray" style. So the pressure differential from top to bottom might have been more like 3 atmospheres than 9. Then that volume would be reduced by 2/3, leaving not much pressure at all to act on the hull structure.

Not only that, but the whole section must have stabilized in a keel-level attitude (trimmed a little stern low) fairly soon after detaching, and before terminal velocity had been achieved. I say this because I have no mechanism to explain how the stern could have leveled out much later. This early righting, I believe, would minimize both the fore-to-aft flow necessary to peel the poop deck off as well as the heights over which pressure differentials could operate.
 
Oct 28, 2000
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The whole stern would have been "dry" until the hull broke. Then, boiler room #1 and the reciprocating engine room would have flooded catastrophically. Everything above them would still have been dry.

All is speculation about what happened during the breakup save one thing. The upper decks did not break first. We have an eye and ear-witness in baker Joughin who heard the breakup beneath his feet while in a pantry at the base of funnel #3. He then moved aft on A deck while hearing people running on the boat deck overhead. Joughin's account would not be possible if the upper decks failed first. He would have been swallowed by an opening chasm of ripped steel--which obviously did not happen.

I have seen two TV documentaries that "proved" how the ship broke apart. One used the so-called "third piece" to prove tha the two larger sections were held together by the keel until everything was several hundred feet down. The other showed twisted girders, claiming this was the result of the stern rotating around on the surface as the bow tore away.

Joughin said the ship rolled to port, indicating that the break was probably from starboard to port with the final ripping on the port side. There are witnesses who saw the stern rotate 180 degrees, which is corroborated by the fact it is facing roughly opposite to the bow today.

My timeline work indicates that the stern may have taken up to 23 minutes to lose air (buoyancy) and disappear. This was the period of time when the people in lifeboats heard the great chorus of screaming voices. Based on survivor testimonies, the ship must have come apart while the stern was still floating. My suspicion is that the sinking bow remained connected on the port side, rolling the stern, then rotating and pulling it upright. The bow broke clear as the stern reached near vertical and may have been nearly on bottom before the stern disappeared.

The upturned stern must have trapped a great deal of air, much like an overturned tumbler plunged into a basin of water. This would be the explanation for why it took a while to sink. Air would have been compressed as the stern went down. The amount of compression and damage are unknowable simply because of the maze of rooms, corridors, open ports, etc. through which water and air moved.

An intact ship will always right itself on the way to the bottom if the water is deep enough. The ship's center of gravity forces this to happen once all buoyancy is lost. That is why the nearly-intact bow arrived on the bottom as it did.

The stern hardly resembled an intact ship from a center of gravity standpoint. It had all sorts of engine weight concentrated at the broken end near the keel. So, I see it plunging most or all of the way in nearly the same attitude as it left the surface. This gave plenty of time for slipstream water to "peel" back the poop deck.

My chronology indicates that the screaming of people trapped on the stern section could have gone on for the better part of 20 minutes. During this time the lifeboats were powerless to act. With too few skilled oarsmen, it would have been suicide to row back to the rolling, pivoting, standing-on-end, and sinking stern. Yet the survivors could hear the screams. The destruction of the stern is nothing compared to what that experience must have done to the human soul.

-- David G. Brown
 
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Alicia Coors

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I have no doubt that the keel collapsed under compressive loads while the upper hull and superstructure resisted the tension loads on them. I know of no other way to explain the existence of the "third piece" which was the part of the keel that separated when it was accordioned into a "Z" shape.

But the "water tumbler" analogy ignores the fact that the broken end of the stern was nearly horizontal before its residual buoyancy forced it vertical. During this phase, massive flooding would have filled the "glass" more or less half-full before it was fully inverted. The amount of destruction of internal structures by the force of water rushing in can only be speculated.

I am not sure that the engines shifted the center of gravity significantly, because although the engine rooms did have large masses in them, they did not contain any decks, bulkheads, or other supporting structures, which to me averages out to a wash versus the mean density of the rest of the ship. If the broken end was forced down by the mass of the engines (creating a flow that would peel back the poop deck), then a mechanism must be proposed that would cause the stern to level out before reaching the bottom.

"Is the glass half-full, half-empty, or inadequately designed?" - Old engineering proverb
 
Apr 26, 2017
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people are saying the bow wasnt as flooded as movies depict it, when she breaks free of the stern. so why, with all this air trapped withen such a large thing. did it not implode like the stern
 
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Aaron_2016

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The stern was pulled down against its will by the bow. The air did not have time to expel and the stern imploded. When the bow partially broke on the surface the water would rush into the broken end and down the forward grand staircase and also down the opening after the forward funnel fell. Survivors near the forward boat deck were sucked down by the water rushing into the bow section and were blown out again by the air as it expelled out. Lightoller thought the water was rushing down the ventilators and into the boiler rooms causing the boilers to explode. Lightoller - "I was sucked down, and I was blown out with something pretty powerful when the ship went down.....this explosion, or whatever it was, took place. Certainly, I think it was the boilers exploded. There was a terrific blast of air and water, and I was blown out clear."


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Kyle Naber

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Oct 5, 2016
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When the stern was dragged down, windows would shatter, refrigerator untits would explode, cranes would swing out, and decking and people would be blown off. The bow, however, had plenty of time to flood. Almost three hours. The stern was much more violent, but Aaron is right about air still trying to escape from the bow from Lightoller's account when the plunge began.
 

Harland Duzen

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Jan 14, 2017
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Don't forget the Cork from the stern storage areas, passengers and survivors did notice Cork on the water's surface and that obsiously being buonant tried to escape the stern.
 

Harland Duzen

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How heavy were both Grand Staircases? I doubt they be strong or buoyant enough to have much effect (I have seen the 1997 incident but don't think that was major enough).
 

Kyle Naber

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In my opinion, the water intake of the collapsing dome was much more catastrophic than what is shown in the movie. I think that it caved in when the water completely covered the skylight, so that when it failed, it was a cyndirical column of water. At this point, the lights in the area would have failed, making it pitch black and filling up RAPIDLY, probably within a few seconds. Also, the 1997 set was built heavier and bigger, so the fact that was able to be torn out with the safe amount of water they flooded the set with, I truly believe that that is what happened to both grand staircases. I don't think they came out whole, however. They were most likely torn apart and forced out of the opening in the boat deck.
 
Apr 26, 2017
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Hey Alicia
There was alot of air trapped in the stern section and as the pressure increased it began compressing the hull til it literally exploded from its compressed air. Also i think it had a hard hit on the bottom which couldnt have helped.
I have a bit of a question. On another thread I saw ppl saying that the bow had a lot of air in when she broke. The questionis. Why didn't it implode (the bow) implode much like the stern did
 

Kyle Naber

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I have a bit of a question. On another thread I saw ppl saying that the bow had a lot of air in when she broke. The questionis. Why didn't it implode (the bow) implode much like the stern did

James Cameron in his Final Word documentary in 2012 used a deck of playing cards to explain this. Imagine you're in a fast-moving car and you open a box of cards and take them out. You roll down your window and lean out so that the back of your hand (facing the wind) is first with the cards held by your fingers in the back (with the wind). Nothing happens. Your hand is blocking the intake of air. This represents the bow which dove down with ease. But if you put the cards first and your hand second (palm against the wind), the air comes in between each card and the pile explodes and the cards go everywhere. This represents the stern which was extremely vulnerable to further damage. I wish I could find a better way to explain or find the link to the video somewhere.

The bow was a dead weight when it went down. It had millions and millions of gallons of water inside of it at the time of the break up. In fact, 20 minutes after the collision, about 1,000,000 were already inside. Just imagine almost what three hours would do! As she further sank, the bow lost boyancy and the stern maintained it, resulting in the down by the head sinking. At 23 degrees, the ship breaks, the bow drops like a stone, but it is still attached by the double bottom and possibly one or two lower decks. This causes the stern, which is still completely dry, to be pulled down, heaving the tail end up into the air. But the water is entering MUCH quicker than the air can properly escape. This resulted in explosions of windows, decking, and various other things, which explains a "rumbling noise" combined with shifting objects that almost all say that they remembered.

There is a good commentary about the final moments in this video which is an old work in progress:

(Skip to approximately 2:43:00)
 

Harland Duzen

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Jan 14, 2017
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In my opinion, the water intake of the collapsing dome was much more catastrophic than what is shown in the movie. I think that it caved in when the water completely covered the skylight, so that when it failed, it was a cyndirical column of water. At this point, the lights in the area would have failed, making it pitch black and filling up RAPIDLY, probably within a few seconds. Also, the 1997 set was built heavier and bigger, so the fact that was able to be torn out with the safe amount of water they flooded the set with, I truly believe that that is what happened to both grand staircases. I don't think they came out whole, however. They were most likely torn apart and forced out of the opening in the boat deck.

True considering they also didn't build C-Deck in the 1997 model. I surprised no one made a psychic simulation of water entering the staircase to see what effect it might have had.
 
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Aaron_2016

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What happened to the Britannic's staircase when she sank? The water would have rushed in very fast as she sank in a much shorter time. Did this cause her staircase to break apart and float to the surface? Did survivors report any large pieces of wood on the water?

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Harland Duzen

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I guess the open portholes allowed water to flow around the staircase more evenly, also her capsizing allowed the air not to flow upwards though the dome and build pressure.

Is it possible, it was't fitted and just a simple stairwell was installed instead?
 
Apr 26, 2017
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thank you. i am full aware of titanic honor and glory and in fact follow them closley . but i still wonder ..... you say the bow torpedoded down .. with ease but when she leveled out . and hit the bottom there must have been still some air. or was it all lost when is contacted with the sea floor
 
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Apr 26, 2017
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What happened to the Britannic's staircase when she sank? The water would have rushed in very fast as she sank in a much shorter time. Did this cause her staircase to break apart and float to the surface? Did survivors report any large pieces of wood on the water?

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brittannics staiecase was marble. hard rock. and as far as i can tell it went down with the ship. also it is not likly the dome exploded or imploded. she went down to quickly. in stead it is much more likly that is crashed and broke when the brittanic settled. and its also unlikly that any part of the ship imploded or exploded. even though she sank quick. she had more holes. more places for the air to escape making her completly a dead waight by the time she hit the bottom. and on another note the depth of the brittanic is far smaller than her sister . and portholes still remain intact on the wreck so i find it more than likely that the same exist on the brittanic
 
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Aaron_2016

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The 'big piece' was reportedly blown off the wreck when the ship broke in two. Perhaps the air pressure was building up inside which caused the portholes to break and blow right off the hull, even the wall mounts that secured the portholes at each end of the hull piece have been blown right off. It must have been a terrific expulsion of air.



shipbreaking.PNG


bigpiece.PNG


bigpiece2.PNG




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