hi!
these are sailboat plans i pulled up, (very rough)... made for a bendable material like coro, or foamboard or something.... i doubt balsa can be used but worth a shot....
this is just the hull... still have to figure out a proper mast size....
includes all crossbeams, and a tray to load the electronics on...
i will decide on a balast weight once i have got the sail height and area

length is 20 inches (50.8cm) bow to stern

finished model:



breakup of parts:



templates:


















hope it helps someone....
-aniket

You have to calculate the mast height based on sail area, then based on that keel depth & weighting 

@sanjay sir mast height is 35'... that balances the keel well

Sent from a potato using a lamp

Great. Now young man, build it!