Isn't that what a keel does?
I suppose though a drone has more flexibility in design parameters by not having people and people-related supplies on board.
But to be honest, I have very little knowledge on this topic, so maybe a keel is all it needs!
On a traditional boat the sails can dig down in the water and needs to be released rather quickly, and you don't want the hatch to be open, but neither of this seems to be a problem here.
That said, I don't know much about sailing other than it being on my bucket list of things to learn so I've been reading up on it, and I've been actively searching for a good simulator that works on gnu/linux... (anyone know of one?)