PeterChappell
Member
Could an improvised barrier have been rigged up on Titanic's E deck above the E bulkhead, and would it have delayed the flooding for long enough to save those left on board? I understand Captain Smith was trying to find the Carpenter after he had 'sounded the ship' with Andrews, could this have been what they were thinking of?
The Titanic took on around 10,000 tonnes of water in the first 40 minutes after the iceberg collision; this compares with its displacement of approximately 50,000 tonnes. The net rate of flooding rapidly reduced to around 1000 tonnes/hr as the height of water built up above the breached portions of the hull, and the pumps were put on line. These figures are based on flooding rate estimates from Figure 10: 'Time history of total floodwater' in Stettler & Thomas. However, after that time there was a gradual increase in flowrate, eventually leading to the ship sinking about 2 hours 40 minutes after the collision.
The water must have moved along the two corridors of E deck across the top of bulkheads until it met stairs which led down to F deck giving the water free access to another compartment to flood. This pushed the ship down further, moving the water further along E deck until it met more stairs across another bulkhead and so on. These two corridors were key channels for rapidly flooding lower and aft parts of the ship without having to increase the head of water which otherwise would have slowed it further.
Therefore, perhaps the best place a barrier to stop the flooding propogating down the ship was directly over the E bulkhead on E deck, effectively extending the E bulkhead upwards. I suggest if carpentry tools and any accessible timber from the store had been taken to this spot by 00:25 when the water started reaching this line, perhaps there was have been a good chance of erecting a temporary barrier. This might have provided the extra time needed for a rescue the occupants or even save the ship.
How would this have been implemented in the short time available? I suggest an improvised 2-3 foot high wood panel, possibly made of a door, tables or (if time permitted) cut from timber wedged between the starboard corridor walls, followed by the wider 'Scotland Rd' corridor. Tarpaulin cut from the hold covers could have been used as well, although a perfect seal wouldn't have been necessary. The barriers should then have been supported and buttressed by further strips of wood nailed up the walls and along the floor behind the panel, stopping water flowing along the bottom of the corridors. Starting with a low barrier height and building it up would have allowed workmen or stragglers from the rooms just in front of the barriers who couldn't reach the stairs to D deck. Once this had been completed, some attention could have been given to sealing any doors across the new bulkhead line. In the hours ahead, these doors and walls could have been buttressed as the height of water and pressure increased.
How much time would a barrier blocking off the E deck above the E bulkhead have given the Titanic? The net flooding rate around 1 hour after the collision (~1,000 tonnes/hr) can be compared with how much water the barrier could hold up towards the bow. For a rough estimate of volume, the area from the barrier to the bow is assumed to be a simple triangle with its base at the barrier and apex at the bow. Obviously this underestimates the volume of the ship towards the bow, but this allows for some of the space taken by structures such as furniture and goods. The average height of water is estimated from lines drawn from the centre of turning (from Halpern), through the bottom and top of the barrier towards the stern. This is coloured green in the attached diagram. Since the angles assume ingress of water to the stern of E the ship, rather than being held up this is only a ball point figure. The answer is 3788 cubic metres which gives an extra 3 hours 47 minutes or until 04:12, around the time the Carpathia arrives.
The second way is to assume an asymptotic relationship between water height up the bulkhead and flood rate. This assumes the flooding reduces to zero at some bulkhead height, as would be expected from theory if the extended barriers were completely successful, and this was the only flooding line. The height is determined by curve fitting five points between 11:40 and 0:25 hrs using an asymptotic model between flow and time after impact. Then the flow at later time periods can be estimated. This suggests the flooding would stop after 13,218 tonnes of water had entered the ship, or 2850 tonnes had been held up behind the barriers which takes the water to about 75% of the way up the new barriers. The same type of model can be used to relate the angle of trim to time after impact, from Halpern. This suggests the height of water would stop around the top of such E deck barriers, or the top of the green area.
H&W's naval architect Edward Wilding presented a plan which showed how the Titanic would trim down by the head as individual compartments are flooded. A screen-capture of a gif file from his findings (3) illustrates the height of water which would be reached after the first five compartments have filled, which is approximately what we are trying to determine here. This indicates the water will reach about 15% over the height of bulkhead E or a trim angle of 4.2 degrees. This is the approximately height of E corridor, the same as in the 'angle of trim' calculation above. The sequence also suggests that the front upper compartment probably remained dry until the water level on E deck reached a certain height. So shoring up E deck may have provided enough time to prepare a barrier there as well.
The accuracy of these calculations depend on reading flows, angles and lengths from the graphs and diagrams in the references, since I don't have access to the exact figures. It also ignores any potential increase in flooding rate in boiler rooms 4 and 5 after 00:25 which could overcome the pumps. The rush of water observed between the boilers in boiler room 5 observed later was probably the coal bunker wall fracturing from the head of water built up in that space. This would have merely redistributed the water over that wider area, although the reduced head would increase the flow again. There's also some evidence that the flooding in boiler rooms 4 and 5 was relatively small and the pumps were successful at controlling the flooding here at least for a time. Perhaps these rooms were abandoned due to flooding seeping in from G deck above or trapping the exits, rather than from below? This wouldn't have happened if the E bulkhead had been raised.
References
(1) Figure 10 Flooding and Structural Forensic Analysis of the Sinking of the RMS Titanic J.W. Stettler (M), B.S. Thomas (M)
(2) Page 2 Angles of Trim and Heel (Revised August 2017) Samuel Halpern
(3) FloodingByCompartment
The Titanic took on around 10,000 tonnes of water in the first 40 minutes after the iceberg collision; this compares with its displacement of approximately 50,000 tonnes. The net rate of flooding rapidly reduced to around 1000 tonnes/hr as the height of water built up above the breached portions of the hull, and the pumps were put on line. These figures are based on flooding rate estimates from Figure 10: 'Time history of total floodwater' in Stettler & Thomas. However, after that time there was a gradual increase in flowrate, eventually leading to the ship sinking about 2 hours 40 minutes after the collision.
The water must have moved along the two corridors of E deck across the top of bulkheads until it met stairs which led down to F deck giving the water free access to another compartment to flood. This pushed the ship down further, moving the water further along E deck until it met more stairs across another bulkhead and so on. These two corridors were key channels for rapidly flooding lower and aft parts of the ship without having to increase the head of water which otherwise would have slowed it further.
Therefore, perhaps the best place a barrier to stop the flooding propogating down the ship was directly over the E bulkhead on E deck, effectively extending the E bulkhead upwards. I suggest if carpentry tools and any accessible timber from the store had been taken to this spot by 00:25 when the water started reaching this line, perhaps there was have been a good chance of erecting a temporary barrier. This might have provided the extra time needed for a rescue the occupants or even save the ship.
How would this have been implemented in the short time available? I suggest an improvised 2-3 foot high wood panel, possibly made of a door, tables or (if time permitted) cut from timber wedged between the starboard corridor walls, followed by the wider 'Scotland Rd' corridor. Tarpaulin cut from the hold covers could have been used as well, although a perfect seal wouldn't have been necessary. The barriers should then have been supported and buttressed by further strips of wood nailed up the walls and along the floor behind the panel, stopping water flowing along the bottom of the corridors. Starting with a low barrier height and building it up would have allowed workmen or stragglers from the rooms just in front of the barriers who couldn't reach the stairs to D deck. Once this had been completed, some attention could have been given to sealing any doors across the new bulkhead line. In the hours ahead, these doors and walls could have been buttressed as the height of water and pressure increased.
How much time would a barrier blocking off the E deck above the E bulkhead have given the Titanic? The net flooding rate around 1 hour after the collision (~1,000 tonnes/hr) can be compared with how much water the barrier could hold up towards the bow. For a rough estimate of volume, the area from the barrier to the bow is assumed to be a simple triangle with its base at the barrier and apex at the bow. Obviously this underestimates the volume of the ship towards the bow, but this allows for some of the space taken by structures such as furniture and goods. The average height of water is estimated from lines drawn from the centre of turning (from Halpern), through the bottom and top of the barrier towards the stern. This is coloured green in the attached diagram. Since the angles assume ingress of water to the stern of E the ship, rather than being held up this is only a ball point figure. The answer is 3788 cubic metres which gives an extra 3 hours 47 minutes or until 04:12, around the time the Carpathia arrives.
The second way is to assume an asymptotic relationship between water height up the bulkhead and flood rate. This assumes the flooding reduces to zero at some bulkhead height, as would be expected from theory if the extended barriers were completely successful, and this was the only flooding line. The height is determined by curve fitting five points between 11:40 and 0:25 hrs using an asymptotic model between flow and time after impact. Then the flow at later time periods can be estimated. This suggests the flooding would stop after 13,218 tonnes of water had entered the ship, or 2850 tonnes had been held up behind the barriers which takes the water to about 75% of the way up the new barriers. The same type of model can be used to relate the angle of trim to time after impact, from Halpern. This suggests the height of water would stop around the top of such E deck barriers, or the top of the green area.
H&W's naval architect Edward Wilding presented a plan which showed how the Titanic would trim down by the head as individual compartments are flooded. A screen-capture of a gif file from his findings (3) illustrates the height of water which would be reached after the first five compartments have filled, which is approximately what we are trying to determine here. This indicates the water will reach about 15% over the height of bulkhead E or a trim angle of 4.2 degrees. This is the approximately height of E corridor, the same as in the 'angle of trim' calculation above. The sequence also suggests that the front upper compartment probably remained dry until the water level on E deck reached a certain height. So shoring up E deck may have provided enough time to prepare a barrier there as well.
The accuracy of these calculations depend on reading flows, angles and lengths from the graphs and diagrams in the references, since I don't have access to the exact figures. It also ignores any potential increase in flooding rate in boiler rooms 4 and 5 after 00:25 which could overcome the pumps. The rush of water observed between the boilers in boiler room 5 observed later was probably the coal bunker wall fracturing from the head of water built up in that space. This would have merely redistributed the water over that wider area, although the reduced head would increase the flow again. There's also some evidence that the flooding in boiler rooms 4 and 5 was relatively small and the pumps were successful at controlling the flooding here at least for a time. Perhaps these rooms were abandoned due to flooding seeping in from G deck above or trapping the exits, rather than from below? This wouldn't have happened if the E bulkhead had been raised.
References
(1) Figure 10 Flooding and Structural Forensic Analysis of the Sinking of the RMS Titanic J.W. Stettler (M), B.S. Thomas (M)
(2) Page 2 Angles of Trim and Heel (Revised August 2017) Samuel Halpern
(3) FloodingByCompartment