Looks like a FLAGG deck with some foam underneath, you can actually see the pink foam if you look closely. I think if there was a 'real' floating prototype, it would have more ship like features such as a bow at least.

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SILENT DUSTY

"...but for a soldier his duty is plain. He is to obey the orders of all those placed over him and whip the enemy wherever he meets him."
- General Ulysses S. Grant