Thread:Qoazi/@comment-24108228-20150805150203/@comment-24899099-20150805163816

In this case it is due to how the boat works, The seat is what is called a "Vehicle Seat", It falls slowly and is rather... resistant to gravity, It is also what provides push, Direction and rotation to the boat

Then there are parts, Just normal parts for looks

Then there's 1 or more part that is called the "MainPart", This part has Incredible gravity and is practically a superheavy object that pulls itself towards the y level water is located at, This is too counteract the seats antigravitational capabilites, But this part only pushes to the waterline, It won't go below it, If it get's below it starts pushing up instead, Therefore making the boat stay level. If we remove it, The seat starts sinking, But is also not pulled towards the water. This is why you can make the Large Sofalike constructs using merchant frigates, The Mainpart is part of the large hull and not one of the sofaparts, Therefore allowing the whole thing to fly.

FYI There are more parts, Specifically "Mast" and "Sail" But they act just like any part.

EDIT: Do note that i have not looked into the code of the game as a whole and know this only because of exploits and experimentation, An Editor could probably explain it much more proper (I'd be interested in knowing too)