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Open the Watertight Doors!

Discussion in 'Collision / Sinking Theories' started by Michael Kestner, May 3, 2012.

  1. *sigh* this one again, eh? There's been a lot of study on this theory Sandy. Frankly, and no offense intended to you personally, it's a load of crap, probably dreamed up by some hack to sell a poorly researched book or documentary. Tank tests with models have shown Titanic would have lost power due to flooding of the boiler and generator rooms much sooner than she actually did, and that she would have rolled over on her side and sank, probably half an hour sooner than she actually did. This is due to the free surface effect, meaning the more free, unrestrained surface area a given amount of water has, the less stable it is. Compare carrying a 12 oz glass of water to carrying the same amount of water in a 8x10 pan or something of that nature for a practical illustration.
     
  2. Michael:

    Not taking it personally. Not knowing enough to assess the theory is the reason I asked, and if I don't ask questions, how'm I gonna learn anything? :)

    Thanks for responding.
     
  3. Scott Mills

    Scott Mills Member

    The science actually shows that Titanic would have foundered 30 to 40 minutes sooner, and would probably have rolled over in the process.

    Also give the location of the boilers, engines and dynamos the ship would have lost all electricity right away.

    So imagine if you will, no wireless (well weak wireless on emergency battery power) and trying to evacuate an unstable Titanic in the dark.
     
  4. Austin018

    Austin018 Member

    I have seen this theory before stated in a few documentaries and books---an it was debunked. Basically if the watertight doors had been left open, the effects would have proved disastrous. Not only was it found the ship would have sank quicker by about some 30-40 minutes, but it would have also started to list to one side greatly, making a launching of lifeboats difficult to virtually impossible. With water flooding the engines and turbines sooner, power would also be lost sooner in that scenario---and you can image the massive chaos that would arise from that alone. The radio transmission might not even have been sent in time, as that action is essentially what saved the people who survived the initial sinking.
     
  5. Arun Vajpey

    Arun Vajpey Member

    I used to ask this myself a few years ago. Sam Halpern's latest book explains why it would not helped even if they could and had opened the watertight doors after the flooding started. The flooding would have extended to Boiler Room No 1 and taken out the power supply, plunging the interior into darkness and causing panic and pandemonium. Also, it would have upset the ships transverse stability and increase the risk of capsizing. Hepern believes that the ship would have almost certainly sunk sooner and a lot more lives would have been lost.
     
  6. Adam Went

    Adam Went Member

    Michael & Co are correct, once there was a significant amount of water in the ship, even if it was level, it would only take one small shift in the mass of that water capsize the ship, which would in all likelihood have resulted in even more lives lost.

    IMO it's fair to say that regardless of what happened or didn't happen before the ship hit the iceberg, after it the crew did all the correct procedures.....the fact that there's been no conclusive proof that a big mistake was made even a century later should indicate as much.
     
  7. Jim Currie

    Jim Currie Member

    All the WT doors except the ones between boiler rooms 4 & 5 and 5 & 6 were left open. They were opened by hand about 20 minutes or so after impact and never closed again. That's why Titanic sank so quickly after the water topped the wt bulkhead at the rear of boiler room 5. Then began the bodily sinkage and the rapid increase in draft.

    Jim C.
     
  8. Arun Vajpey

    Arun Vajpey Member

    In that case, as a rough estimate how much longer could the Titanic have remained afloat if those watertight doors had NOT been opened again?
     
  9. Jim Currie

    Jim Currie Member

    Now that is an interesting question Arun.

    Personally, I think, just off the top of my head, that she would have lasted quite a bit longer.

    Wilder implied that the beginning of the end started with the water back-filling (or should I say forward filling) into the spaces above the forepeak tank once it had topped watertight bulkhead 'A'.
    This caused the bow to sink deeper. Consequently the water level at the aft end of boiler room 5 rose enough for it to spill over into boiler room 4. and further along Scotland Road due to the port list.
    It would then find it's way through the firemen's access doors which were probably left open and pour back down into the next compartment This cause and increase in bodily sinkage and a sudden increase in the port list. The latter because all the doors to the port side cabins were open.
    As the water progresses aft, it's passage would be restricted to the tops of the bulkheads and the port list.

    However, the free surface effect mentioned by Michael would be kept to a minimum. Because of this, and the steady increase of bodily sinkage (the water was entering spaces nearer and nearer to the midship point) so the overturning effect would be reduced. There would be no free surface effect forward of boiler room 6 and it would disappear when 6 became full.
    It would not re-appear until the water level in 5 was above the tops of the boilers and would disappear again when that boiler room was filled and so on.

    Free surface is exactly the proper description. It is the area of the water surface (not the depth of water) that is critical.
    To counteract it, ship tanks are subdivided to break up the surface area.
    In the case of Titanic, there would be very little effective free surface until the water rose above the tops of the boilers in the boiler rooms and it would disappear when the boiler rooms were full.
    In the engine room, there would not be any free surface until the engines were covered. It would disappear there too when the engine room became filled.

    Incidentally, it does not act alone in destroying a ship. It has allies such as the ship's centre of gravity and her centre of buoyancy to mention the two most important ones.

    As I said, and interesting point.

    Jim C.
     
  10. Jim

    You're the expert here, of course, but I've seen the plans Wilding submitted to the BOT inquiry. If my memory serves right, one of those showed the ships trim with the forepeak, holds 1-3, and BR 5 and 6 flooded and partial flooding in BR 4...in that condition, Titanic was almost gone as far as I could judge. She was submerged almost up to the base of the first funnel, which if I understand correctly is pretty close to when she started to come apart. I'm interested to see how you come to the conclusion that she would have lasted much longer if those doors were shut.
     
  11. Arun Vajpey

    Arun Vajpey Member

    Thanks Jim. But may I ask in your opinion, how long is "quite a bit longer"? A hour? 2 hours or more? In other words, long enough for the Carpathia to arrive on the scene?
    That in itself makes me want to ask a related but hypothetical question. If a ship like the Carpathia had arrived while the Titanic was sinking albiet more slowly than it actually did, how much further time would be required to safely transfer everyone from the Titanic to Carpathia? Would that have even been possible given the equipment they had at the time?

    Also, I was under the impression that Boiler Room 4 had started flooding before the rising water from BR5 overtopped the bulkhead? How does that equate into - if at all - the free surface effect that you mentioned?
     
  12. Jim Currie

    Jim Currie Member

    Hello Michael,

    I'm no expert... still learning:D

    I will try and explain my thoughts about the effect on the sinking process with WT doors being opened
    or closed.

    Forgive me if I point-out the obvious.

    A ship will sink if it is heavier than the amount of water it displaces. Consequently we do not overload a ship!
    A ship will also sink if the force of buoyancy keeping it above the surface of the sea is removed.

    In simple terms:
    If we add weight to a ship and keep adding it, it will sink.
    If we remove buoyancy and keep removing it, the ship will sink.

    Titanic sank by a combination of these two processes .

    First, the puncturing of holds 1 and 2 and boiler rooms 6 and 5 caused her to lose buoyancy. i.e. extra weight was not added to the ship to make her sink. The forepeak tank was holed as well but it was full of water beforehand so once again no added weight!
    Thus, the ship intially lost buoyancy and in doing so sank by the head. This continued until the water level reached the top of the Collission Bilkhead.. the first bulkhead after the bow...WT Bulkhead 'A'.
    As soon as it did so, the water poured over the top and, because the ship was tilted by the head, poured forward and over the bulkhead into the empty storage compartments above the Forepeak tank. This caused the bow to sink a little more. However this second part of the sinking process was due to the added weight of water not to the original loss of buoyancy.
    While this was happening, the ship was still loosing buoyancy and would continue to do so until every compartment open to the sea was full.( A little simplified but sufficient for our purpose!)

    Leaving all the WT Doors open:

    If all the WT doors were left open, the ship would become one entire compartment open to the sea and the sinking process would be one of continuous los of buoyancy.
    The water would flow from its source.. the hull punctures.. and make its way right to the stern.
    In this way, the loss of buoyancy would have been more evenly distributed along the entire length of the ship. There would be no more added weight and she would settle in the water until the entire bouyancy was lost.
    However, more to the point, I do not think the hull would have fractured!
    Leaving the WT doors open would have allowed the ship to settle evenly. The loss of buoyancy would have been at a steady rate. Consequently, this might just have prevented the hull from fracturing thus the moment of sinking might have been delayed for a very brief time
    However, the rate of loss of buoyancy was relentless and when the amount of buoyancy needed to keep Titanic afloat was all used up then it was all over.



    Next:

    Leaving all the WT Doors closed:

    If all the WT doors had been left closed then Titanic would have lost buoyancy in 4 compartments.. Nos 1 & 2 holds and Nos 6 & 5 Boiler Rooms.

    These would have to be filled before water poured into the successive compartments astern of them. Thereafter. the sinking process became one of added weight rather than lost buoyancy. The length of time the ship remained above the surface would depend on the rate of filling each intact compartment and this would finish when the amount of water equal to the total volume of Lost buoyancy plus added weight of water was greater than the weight of the amount she displaced before the accident. 48,300 Tons? or 1,690,500 Cubic feet of sea water.

    Partial closure of the WT Doors: (The actual situation when Titanic sank)

    We know that the WT doors forward of Boiler Room 4 were closed and that there was a small amount of water coming into the forward bunker in Boiler room 5. This means that buoyancy was being lost in all comparments forward of Boiler Room 4.
    Because the water was entering 5 slower than 6, the water level in 6 was rising faster in there and finally overtopped the WT bulkhead between 5 and 6. While this was happening, the water level in the forward bunker of number 5 had been rising. Eventually the bunker doors collapsed under the pressure and the combined flooding would be free to move aft toward the WT Bulkhead between 4 & 5. Because the WT door between these compartments was close, it would then have to rise up that bulkhead before it gained access to Boiler Room 4.

    As I pointed out earlier, all the sinkage up until the water reached that level was due to loss of buoyancy. This being the case, The center of gravity did not move from it's original place. However, the Center of Buoyancy would most certainly have moved amd the Center of Gravity would have tried to follow it. The result was a complicated series of stresses which caused the hull to fail at it's weakest point.
    A fracture below the waterline, allowed extra sea water to pour into the main engine room and travel forward and aft through the open WT doors. This sudden influx of water caused the hull to sink bodily. What is more, it returned the sinking process from one of gaining weight to once more, one of losing buoyancy. Weight was no longer being added to the hull from water entering a sealed compartment.
    Because the WT doors at the aft end of the engine room were open and thereafter, open to the end of the shaft tunnels, the water very quickly went aft and the stern lost buoyancy in a complicated sequence. This agravated the bending moment and the stern section bent back level with the sea.
    Perhaps if the WT doors been closed at the aft end of the Main engine room, it is just possible that there would have been enough retained buoyancy in the stern section when it broke free of the forward section.
    Perhaps some of those on the stern section might have lasted long enough to be saved.

    Here's another poser:

    If the lights stayed on until the last moment; where did the power come from? The generators needed steam and steam came from boilers. This means there must have been a supply of steam to the main or emergency generators right up until a few moments before the end.

    Sam Halpern wrote an article "Why a low Angle Break" In it, he showed a sketch of Titanic with a waterline right up to the masthead light and extending aft to meet the sea at the last WT Bulkhead.
    Sam's water line shows the engine rooms and boiler rooms completely inudated. If this was the final waterline, where did the steam come from to light the masthead light and the rest of the ship?

    If there was enough electric power to serve all the ships lights then the steam to generate it had to come from Boiler Rooms 2 or 3 because the 5 single end boilers in Boiler Room 1 had never been lit and the Boiler Rooms forward of No.3 were flooded
    It follows that the length of Titanic's keel above the surface of the sea must have been much greater at the time when the lights went out. I have made crude modifications to Sam's sketch and included suggested water lines as the sinking progressed.
    However here's another mystery:
    Although not shown, if Wilder's assumed down flooding of 1600 tons in the first 40 minutes is correct, then Titanic' forward draft would only have increased by 9.3 inches and her aft draft decreased by the same amount.

    low_angle_image001.jpg

    Any comments?

    Jim C

    low_angle_image001.jpg
     
  13. Just making sure I understand correctly, but are you suggesting it's possible the stern may have broke off and floated for a while on its own if the doors aft of BR 4 were shut?

    I was sure I'd read somewhere around here that the doors in the engine rooms have been seen to be shut on the wreck, but I could be totally mistaken. I would imagine they'd have shut on their own, due to the float mechanisms under the floor plates, but I could easily imagine the bulkheads warping enough under the strain of the breakup to prevent the doors from closing (or becoming less than watertight if they were closed, for that matter).

    Also, not sure if that was a simple typo or not, but Wilding's calculations for rate of flooding assumed that she took on 16,000 tons of water in the first 40 minutes, not 1,600. 1,600 tons in 40 minutes would have been well within the bilge pumps ability to bail out.
     
  14. The WT doors were shut. This was seen on the wreck like the door leading from the reciprocating engine room into the turbine room.



    Leaving all WT open would have lead in a loss of power and the ship would have capsized before any lifeboat would have left the ship.

    Most likely from BR No. 2.
     
  15. Jim Currie

    Jim Currie Member

    Hello Michael!

    You are correct! I mis-read the 16,000 as 1600 tons. The maths are fairly good though for the 1,600 tons.
    Told you I wasn't an 'expert':eek:

    In fact, 16000 tons is pretty close to the amount of water in the compartments BR6, and Nos.1 & 2 hold when the water level reached the top of the WT Bulkhead between 6 & 5.(allowing for permeability.. boilers, coal and cargo etc)

    I have re-worked my sums and find that Titanic's forward draft would have increased by 8 feet. However, the ship would sink bodily as well so the final draft at the bow would be in excess of 10+8 feet = 18 feet giving an overall draft at the bow in excess of 48 feet which puts the water line just above the haws pipe.
    This is almost exactly right for Wilding's waterline to the top of The aft Bulkhead in Boiler Room 6. It also means that 40 minutes after sinking, Titanic's hull was out of the water from the WT Bulkhead between BRs 2 & 3 and her stern. Shown by the yellow waterline in the sketch below.

    An hour and a quarter later, when the water reached the top of the WT Bulkhead between BRs 5 & 4, her hull had settled back down a bit and was out of the water from the WT Bulkhead between the main engine room and BR 1. Shown by the white waterline in the sketch below.

    low_angle_image001.jpg

    The three yellow dots marked (1),(11) and (111) are the positions of the Center of Floatation. Each yello dot represents the center of gravity of the ship's Water Plane. The ship's water plane is the water-line area of sea-surface occupied by the ship at any single moment. If that area changes then so does the position of the Center of Floatation. When a ship tips by the head or stern, it rotates round The Center of Floatation. For simple purposes, I have assumed it was mid-way along the length of the water line and on the longitudinal center line of each waterplane area.

    Sam's water line never existed. Simply because there would be no steam to generate power. And because he seems to have used the original pivot point for his calculations. I don't know. Perhaps I'm wrong and he might explain?

    What is absolutely sure is: Wilding's calculations were fairly accurate and Titanic's hull was suspended in thin air far too long for it to remain intact. It was not designed to do so nor is the hull of any other ship for that matter.

    Hello Ioannis!

    As for the Water Tight Doors being found closed on the stern section. That is very strange indeed. There is a very long exchange between Greaser Frederick Scott and Lord Mersey during which, Scott explains in great detail how he and the others raised all the WT doors from the Main engine room to the stern tubes. it end as follows:

    "The Commissioner:

    Then all the watertight doors aft of the main engine room were opened?

    5600. (The Attorney-General.) Yes. (To the Witness.) And, so far as you know, as I understand it, they never were closed?
    - No. Why they opened them was they had to go down the last tunnel but one and get a big suction-pipe out, which they used for drawing the water up out of the bilges"


    There was no way these doors could close by themselves once they had been raised manually.
    The float was only to disengage the automatic raising system so that they could be raised using the winding handle. Here's one I made earlier:

    WatertightDoor.jpg


    Ioannis, you wrote:

    "Leaving all WT open would have lead in a loss of power and the ship would have capsized before any lifeboat would have left the ship".

    I can understand the loss of power problem but the capsizing needs a bit of explaining. How did you arrive at that?

    To re-cap:

    For the first hour and 55 minutes, Titanic shipped 16000 tons of water. That was an average shipping rate of just over 139 tons per minute into 3 breached compartments or if you like, a loss of buoyancy rate.
    Checking this by Barrett's evidence: he said he returned to Boiler Room 6 after about 10 minutes and it had something like 8 feet of water in it. Using a permeability of 50% this means that the boiler room contained about 560 tons of sea water after 10 minutes flooding. That's a flooding rate of 56 tons/minute.
    That leaves 84 tons/minute into each of the holds. avergage 42 tons per hold seems reasonable considering thy contained cargo.

    With all the WT doors open, this down-flooding would have continued at that rate.
    For Titanic to completely lose all her buoyance and sink, she would need to get rid of 48,300 tons of it. Up until 1:55 am, with 4 compartments closed, she had lost about 16000 tons so she had to lose another 32,300 tons. That should have taken another 195 minutes or 3 hours 50 minutes meaning that Titanic should have finally gone down at or near to 5-45am, an hour and three quarters after Carpathia arrived.

    If all the water tight doors had been left open and the water allowed to run freely aft, the ship would have remained more or less upright and on an even keel. for about the same length of time. However, in both cases, we do not include any allowance for permability of all the various compartments in the ship above the boiler casings. Nor do we know whether or not they wera able to use the full amount of pumping power.

    As for there being no light: All passenger ships were supplied with many oil lamps. This was seen when the lighting was lost ijn NO.5 Boller room. While not the best sollution, it would have been possible to get everyone up to A deck and the Boat deck. If the flooding times are right, then if the hull had not fractured.. free flooding or not, the passengers and crew would have had an hour and a half of daylight the conforting sight of a nearby ship and the use of her extra lifeboats to get everyone off Titanic.

    Hindsight is a great thing!

    Jim C.

    low_angle_image001.jpg

    WatertightDoor.jpg
     
  16. Dan Johnson

    Dan Johnson Member

    Hi Jim,

    If I can chime in...

    As a vessel sinks lower in the water the center of buoyancy changes. It moves up closer to the metacenter. At the same time the metacenter is decreasing because the waterplane of the ship is being reduced.

    What this all means is that the ship will become unstable. It will not be able to right itself, or keep itself upright as these two points get closer together.

    The other part of the equation is that all that water will be sloshing around in the hull, free surface effect. That's why big tanks have baffles in them, to stop this from happening. Any movement on the ship would cause a roll from which it could not be recovered.

    Damaged vessels become unstable very quickly. Titanic was fortunate that she was able to stay upright as long as she did. Most vessels capsize, like the Lusitania. The Titanic foundered.

    Dan
     
  17. Jim Currie

    Jim Currie Member

    Hello Dan!


    Titanic was down by the head so we have to consider the fore and aft movement of these Centers.

    The center of Buoyancy would have moved about 46 feet forward and slightly down. to be in the vicinity of the top of the boilers in Boiler Room 3 (If my sums are correct which is not always a certainty)

    Here is how I think it might have been that morning at about 01:55am:

    View attachment 411

    The position of 'G' did not change since extra weight had not been added to the ship

    "As a vessel sinks lower in the water the center of buoyancy changes. It moves up closer to the metacenter. At the same time the metacenter is decreasing because the waterplane of the ship is being reduced."

    I'm note sure what you mean here. Perhaps I've reached the limit of my knowledge?

    I was taught that when a ship sinks deeper in the water and heels to a small angle, the Center of Buoyancy..'B'.. moves down and out to assume a position which represents the center of gravity of the underwater part of the ship. The Center of Gravity.. 'G'.. also moves down if the sinkage is due to added weight. The Transverse Metacenter 'M' is the point at which a line drawn vertically through 'B' meets a vertical line drawn upward from the keel.
    The same applies when a ship dips by the head although in this case, we are dealing with the Longitudinal Metacenter.
    As I said earlier.. Titanic did not sink because of added weight so 'G' would not move downward. Neither would 'M' move as long as the ship maintained or increased the length of her original waterline.
    Whe she tipped by the head, 'B' moved slightly down and forward. When she heeled about 5 dgrees to port, it move slightly down and out to the low side.

    Whe Titanic was first holed, it seems she heels a little to starboard then came upright and started going down by the bow. Later, she developed a port list. For the rest of her short life, the major out of level cause was trim by the head, which would have increased until she started taking on weight in number 4 Boiler Room. Then , the tipping by the head would slow down and bodily sinkage would increasingly become the mechanics. At that moment, the waterplane area would start to increase. There would be a temporary period during which weight was added to the hull but as soon as the hull fractured, the water would all be flood water and would have progressed rapidly aft and the waterplane area would eventually have been restored to it's initial value. All this time, the ship would be losing buoyancy and getting deeper in the water. The center of buoyancy would be constantly changing it's position and getting deeper below the sea surface.

    As for free surface effect. It is, as you might well know, phenomenon whereby , if a weight is free to move about (as with water in a ship's tank), its effect is as if its Center of Gravity were somewhere above the weight instead of being at it's actual position. This is called the virtual center of gravity.

    The formula for finding out the effect of free surface effect on a ship is in two parts.
    The first part deals with the downward movement of the Center of Gravity due to added weight below its original position.
    w x Gg
    W

    and

    i
    V
    Small w represents the weight added to the compartment so that renders that part of the formula ineffective since weight was not added.

    I have run the FS figures for boiler room 6. If there was any free surface at all, it would reduce the GM by about 3.5 inches. Similar free surface in the remaining boiler rooms and main engine room would reduce it by a total of about 2 feet. This would still leave a positive GM.

    In reality. the compartments forward of BR 6 were very well broken-up and had a high permeability so free surface would be almost non existant.
    In addition, Titanic was sinking by the head, the forward compartments were flooding progressively therefore, even if the doors were all open, by best guess is that the FS effect would never have reached a total combined effect whereby the ship became unstable and rolled over.
    As an aside. the greates amount of FS, if it happened, would have taken place when the water level just cleared the tops of the boilers and would completely disappear when the water reached the the top of the boiler rooms.

    Jim C.
     
  18. Jim Currie

    Jim Currie Member

    low_angle_image001.jpg

    This is the bit that got lost!

    JC

    low_angle_image001.jpg
     
  19. Dan Johnson

    Dan Johnson Member

    Hi Jim,

    My understanding is that the center of buoyancy is where the center of gravity of the displaced fluid volume is located. As the hull sits lower in the water the center of buoyancy moves "up" in relation to the keel, down in relation to the surface of the water. It's all a matter of perspective. I see where you're going with this.

    Yes, the CoB moves towards the list.

    I think my question now is the waterplane. As the Titanic sinks by the head the waterplane is changing, it's decreasing. If we assume all the watertight doors were open this would happen in a steadily increasing fashion.

    The water wouldn't fill up the BR's to the top instead you would have that free surface effect taking place over. Closing the WT doors did make the ship more stable by reducing FS, your example of BR6.

    I just don't see the vessel sinking "flat." Water is entering from the bow hence it will go down by the bow first. Water does have viscosity. This is where I see the change in waterplane taking place. As the waterplane decreases the metacentric height decreases.

    It's getting late here. I look forward to your reply.
     
  20. Free surface effect is, indeed, extraordinary and devastating, as I witnessed only yesterday carrying the de-frosting tray from my old little fridge (beer only) to the sink. All over the floor. I'm only glad the big fridge is frost-free. However, such considerations and calculations could hardly have been expected on the night of the 14.04.12.
    "How long, Mr. Andrews?"
    "An hour ... maybe two."
    "But have you considered the free surface effect once the water has risen above the bulkheads, and whether we should keep the doors closed or open and spread the flooding more evenly, perhaps, to gain time and save lives by settling the ship more horizontally into the water?
    "Um ..."
     
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