[baltbalt]

I have a hard time believing you can transfer 20% of the power through the upper deck without rethinking the whole structure.

[bagacrap]

I would imagine the masts travel through the upper deck from their base which is bolted onto the frame, rather than being bolted to the outside deck.

[hypersoar]

If it's like a conventional sailboat, the mast will go all the way down to the keel.

[senectus1]

^this.

especially if the ship is loaded with materials.