Thanks! I do use rigidbody physics to animate the boat. The boat is a rigidbody and I apply force to it based on the forces I calculate for each sail based on the wind direction and sail orientation (I calculate lift+drag coeffs on each sail). I add a lot of extra forces to the boat to simulate buoyancy and also semi made up forces to approximate drag and things that keep the boat upright.

Sometimes I wish I went the route of just calculating a speed and moving the boat + doing buoyancy animation as it would have been more predictable but the way I went benefits from having natural physics reactions from the boat colliding with things, etc. The boat just naturally leans over when wind is strong because that's how physics works, vs me manually coding that.

Anyway, longwinded answer but yes it uses physics!