# It Would Take a Titanic Raft of Flotsam to Float Two Actors

Actual lifeboat from the Titanic, photo taken by a passenger of the rescuing ship: Image courtesy of the National Archives

### Building a Raft Large Enough for Kate

Let’s assume that the door was actually twice as wide; perhaps it slides rather than swings. Then, the volume would be 2 x 1.6 x 0.0127 = 0.04064M^3, which would displace 41.656Kg of water. That’s still far less than Kate’s weight!

So, let’s also triple the door’s thickness; perhaps it was designed for security against burglars or gale-force winds. This new volume would be 2 x 1.6 x 0.0381 = 0.12192M^3, displacing 124.968Kg of water. Subtracting the new door’s weight, we have 124.968 – 54.864 = 70.104Kg.

Since Kate weighs a dainty 61Kg, her much larger door has an excess buoyancy of 9.104Kg to float her above the water. Jack, however, is still in the deep blue sea, and Rose would be too, if he tried to climb aboard.

### Designing a Titanic Raft for Two Survivors

Kate’s door had the capacity to support 70.104Kg, which is almost 2Kg less than Jack’s weight. Since it had 9Kg excess buoyancy for Kate, let’s take an engineering shortcut and simply nail two of these super-sized doors together. Even with the nails, this arrangement would buoy both soulmates as they await rescue.

To duplicate the buoyancy required to support both characters, the pair would need a dozen of the original doors, in order to make a raft that meets our simplified standards for success.

We leave the calculations for the weight of all the extra nails to our industrious readers.

### To Finally Sink this Titanic Raft

An inflatable raft weighs very little, and is very buoyant. Image by Klearchos Kapoutsis

Although any object that floats might assist a poor swimmer, the goal of staying afloat and above water on a “raft” depends on the volume and density of that raft.

In the “Titanic” film, Kate would not have been able to use a single door to remain above water, much less save Jack as well. These math calculations show that Jack would have had to nail together about a dozen standard doors into one improvised raft to have any hope of saving them both without lifeboats from the sinking Titanic.

References:

The New York Times Store. Rare Piece of Titanic Door Recovered at Disaster Site in 1912. Accessed June 7, 2012.

Benson, T. Buoyancy: Archimedes Principle. NASA. (1996). Accessed June 7, 2012.

California Science Project at California State University Northridge. Density of Liquids. (Page 2). PDF. Accessed June 7, 2012.

The Engineering Toolbox. Water – Density and Specific Weight and Wood Densities. Accessed June 7, 2012.

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• Nara

I guess neither Jack, nor Rose (and she was smart, too) were aware of Archimedes principle…too bad, maybe Jack could have lived a day longer or so…but then, the ending had to be gut wrenching, after all.

• http://decodedscience.com W

For the door to support their weight it would have to weigh approx. 560 lb. to float level with the sea surface and more to keep them above. Take some strength to launch it!

• Edward

Bothhh Cannot Sorvive On dahhh Sea With Such Wavesss And High tides ,,,,,, ???

• Will

Really? You’re going with a half-inch thick door as “realistic”? How about this: you show me just one wooden door that’s a half-inch thick and I’ll allow that assumption. Meanwhile, here’s a standard 30×80 door:
http://www.homedepot.com/Doors-Windows-Interior-Doors/h_d1/N-5yc1vZbuhv/R-202523949/h_d2/ProductDisplay?catalogId=10053&langId=-1&storeId=10051
1.375 inches, or about 3.5 cm, about as thick as your “burglar” door.

• Stooge

Your assumption about the thickness of the original door is wrong: as the blurb for the Titanic door fragment clearly states, the piece being sold is 0.5 inches thick, but it “was once a thicker block that years ago was cut up into tiny pieces”.

• moioci

Wait a minute. The NYT site describing the 1/2-inch thick piece of door says, “This relic was once a **thicker block** that years ago was cut up into tiny pieces, which sold for four figures each.” Think about it. Even in today’s world of very cheap construction, a half inch would be very flimsy, even for a closet door, let alone a stateroom door. I vote the actual door was at least an inch thick, possibly more.

• Mike DeHaan

For Will, Stooge & Moioci, who pointed out that the door was probably much thicker…
“Arghh, you’re all extremely likely to be correct”.
Assume 1.5″ rather than 0.5″? So we only need 1/3 the number of doors that I had calculated?
Thank you for taking the time to let us know.