How a Titanic submersible splits and sinks

I've watched thousands of Titanic models sink, and it still gets me.

The mechanism is really elegant. Our T3 model works on the same basic principles as 90s collectable that we based it on.

There's a switch, a break, a latch, and two compartments. That's the whole mechanism.

When you push the switch, it pulls the hull break to open a hole below the waterline right where the real ship tore.

The original 1999 model put this switch on the bottom, so you had to lift the ship out of the water to set it. Ours is a thumb switch on the top deck, so you can go from float to sink mid-sail.

Water enters the forward compartment through the hull break. The bow gets heavy and starts to go under.

But the stern has a totally separate compartment, so it's still trying to float.

The combination of the heavy bow and light stern make it tip dramatically.

Inside the bow the rising water pushes up on a latch holding the two halves together. When the water gets high enough, the latch lets the stern go.

The bow, no longer supported by the buoyant stern, sinks to the bottom.

With the bow gone, the stern has nothing holding it level. It takes on water through its own compartment and sinks second.

Every part of that sequence depends on weight. Ballast, water weight, bow weight, etc.

Too much ballast in the bow and she nose-dives before the latch trips. Too little and she sinks backwards.

I spent months on the T3's ballast, moving a gram here, taking one away there.

And it has to work every time.