Sinking dynamics {What 'actually' happened?}

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Up until 1985 it was assumed that the ship rose up and sank bow first all in one piece. Then Bob Ballard discovered the wreck broken in two large sections and theorized the ship broke up before sinking, which was in accordance with some survivors recollections as well. Now along comes J. Cameron with his computer animations and special effects wizadry to portray these events in chilling and spectacular fashion. However, he shows the ship 's stern rising high,high into the sky before the hull breaks, and it seems to me that the hull would have started to fail almost as soon as the stern, and propellers lifted clear of the water, the only time the stern really assuming a high angle being toward the very end, after the bow broke away.Comments? Any Computer modelers out there who could simulate these conditions knowing approximately the weight and balance points involved?

-- Kenneth More (foo@bar.com), March 13, 1998

Answers

Response to Sinking dynamics

What Cameron depicts is in accord with the currently accepted historical record.

The survivors who maintained that the ship broke in two all speak of the same basic chain of events: at about 2:05 AM the ship, after sinking slowly for about two hours and a quarter, began to flood quickly; the stern (still attached to the rest of the ship) rose out of the water as the bow and bridge dipped completely under the sea; within a very short time, perhaps 5-10 minutes, the ship was at about a 45 degree angle to the water; at this point the hull broke between the third and fourth funnel, with the front 2/3rds of the ship going completely under the water and the aft 1/3 coming back to almost an even keel; within a few minutes of coming back to an even keel, the stern flooded and rose to a 90 degree angle and plunged straight down, gaining speed as it went.

I assume that the stern stayed attached as long as it did because it was strong enough to take a least a few minutes of extreme stress, but no more than that. It also said that there was a structural weak point in the hull at the point of the break. If so, then the stern could certainly have risen some ways out of the water before that weak spot was exposed and put under pressure, since it was 300 feet forward of the aft tip of the stern.

-- Thomas Shoebotham (cathytom@ix.netcom.com), March 13, 1998.


Response to Sinking dynamics

It has been theorized on one of the Harland & Wolff pages: http://www.harlandandwolff-ts.co.uk/hwtech.serv/hwts3.shtml), the essay TITANIC, the story from a ''Shipbuilders'' point of view, as told by Tom McCluskie (halfway down the page) locates the most probable weak point as the furnace ash removal door.
''This door was located some 370 feet from the stern on the port side at E deck level.''

''The position of this door would be approximately the point of axis as the vessel progressively tilted downwards as the bow flooded.''

If the catastrophic failure of the hull originated at the above door opening, it would have (IMHO) caused the break to be asymmetrical, causing the roll/turn of the bow noted by many eye witnesses.

The keel may, ironically, have been too strong: if it had detached sooner, the stern section *might* have stayed afloat longer. The film depicts the submerged bow pulling the stern vertical before detaching; had the stern stayed level, it may have stayed afloat.

-e-

-- Thomas M. Terashima (titanicShack@yahoo.com), March 17, 1998.


Response to Sinking dynamics

Tom, I doubt that the stern could have remained afloat, even if the keel had broken quickly. Remember, the ship broke apart in the area of the reciprocating engine room. Photographs of the stern wreckage clearly show the high pressure cylinders of the reciprocating engines, still bolted to their bedplates and standing upright. Two more cylinders were mounted aft of the HP cylinders (two low pressure cylinders, originally forward of the HPs, have been identified in the debris field near the stern). The engines were by far the heaviest objects on the ship; their weight would have inevitably pulled the forward part of the stern down, allowing the open compartments to flood.

Cameron had access to H&Ws materials; I'm sure their opinions were taken into account in designing the CG animation and model photography of the breakup.

Cheers!

-- Kip Henry (kip-henry@ouhsc.edu), March 17, 1998.


Kip:

I just do not want believe that the entire ship sank; I really want it to have ''didn't happened''. The detached stern staying afloat was the last hope those remaining on the ship had of survival, the one last ''what if''.


The break-up of the hull occurred at the point of maximum stress: when the bow was at a 45 degree angle. Any less, and the weight of the stern would have had more support by the ocean; any more angle, and the stern's weight would have been supported by (directly over) the submerged half.

-- Thomas M. Terashima (titanicShack@yahoo.com), March 17, 1998.


I am a building architect. Therefore, my opinions are limited to my knowledge and experience of static forces. The structures that I am involved with are not required to withstand 180 degree lateral forces like a ship on the water. I can only assert logical thinking when it comes to the Titanic, but considering the "expansion joints" that Tom McCluskie references in "Anatomy of the Titanic", it would seem logical that the ship's structure would have broken apart at the aft expansion joint location, located at the aft one-third of the hull, due to the eccentric forces imposed by the stern being lifted out of the water which would have reversed the forces designed for the expansion joint. According to his book , "Anatomy of the Titanic", on page 43, Tom addresses the expansion joints "inserted above the superstructure above the Bridge deck"....."resulting in the whole superstructure being completely severed at these points". This would offer a great opportunity for the hull to break apart when subjected to abnormal forces such as the stern being forced up into the air as a result of the bow sinking. Morever, the bow would logically descend with a slighter angle due to its dynamic configuration while the blunt-ended stern portion would logically descend more directly toward the bottom. This would account for the great distance between the two locations of the final resting places of the great ship.

That's my two cents worth.

Jim Atkins, FAIA

-- Jim Atkins, FAIA (jimatkins@mindspring.com), September 07, 2002.



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