desertyank said...
I'm curious where the downforce comes from? I have been tempted to make an r/c sailer with a wing, but every time I get close, I read something about the violent tendencies of the designs. Read several articles where a water based yacht is pretty much torn apart when things went wrong....
My explanation of why wings are often violent... they are "normally" supported by wire stays which is attached to the front of the mast with a mast hound, so the mast can pivot from the mast hound and the rotation pin at the base of the mast.
ie. lets assume you are sailing with the wind coming from 45deg L side this creates a low pressure on the R side of the rig sucking the yacht along (sail theory) then when you tack at the
mid point the wind is straight on the front of the mast.
The mast then rotates on the pivot point which then forms a low pressure on the L which swings the mast slightly
against the wind which then creates a low pressure on the R.... so the low pressure switches rapidly L-R-L-R-L-R-L and in a strong wind its a wild ride. On some larger yachts I have seen motor bike shock absorbers being used to help control the mast.
Now why does a wing generate so much down force because of the lay over angle of the mast / wing because of the mast hound point, and because most people with wing masts have flexing axles this lays the rig over further resulting in a down force which ends up at the mast pivot point, rather than the yacht tipping.
(p.s take some spare undies)
Although I dont know much about this either 
