Blind date and rare bird only show signs of 16 knots and the hulls seem to be pushing atlot of water out of the way. Not a knock on either boat , just I want to do better.
What would you say to freeing up the hull with a shallower draft more displacement by just widening hull proportionately or narrowing the keel to reduce waterline beam width and widening sheer width a tad?
Todd
--- In harryproa@yahoogroups.com.au, Rob Denney <harryproa@...> wrote:
>
> BD's lee hull is huge compared to any trimaran lee hull, and plenty big
> enough for the immersions it sees. There may well be an optimal cant angle
> for a particular boat speed, but when the boat has to perform from 0-20, it
> has to be an average.
>
> rob
>
> On Sat, Sep 17, 2011 at 1:55 AM, tsstproa <bitme1234@...> wrote:
>
> > **
> >
> >
> > In the drawing the vertical line above hull represent the rotation of
> > leeward hull due to either sail induced heeling or improperly aligned hulls.
> > I can show incremental heel angle on paint for any unless I draw each one.
> > Still referring to Blind Date and its smallish looking leehull.
> >
> > Put a up another diagram in same folder see both set at vertical static
> > positions no induced preset canting. Each are set as loaded ready for
> > sailing.
> > Each leeward hull in diagram will have a different canted angle when under
> > sail heeling loads while sailing at same speed.
> >
> > When at desired speed range say 16 knots the force exerted on leeward hull
> > requires buoyancy to restrict further sinking/squatting to reduce further
> > canting of hull to maintain optimum performance. If you are already at max
> > canted angle due to low buoyancy or misaligned hulls then performance of
> > hull/boat will suffer.
> >
> > Todd
> >
> >
> > --- In harryproa@yahoogroups.com.au, Rob Denney <harryproa@> wrote:
> > >
> > > Sorry,which post does this refer to? All harrys so far have had pretty
> > much
> > > level decks and vertical masts, apart from one of the early prototypes
> > where
> > > it was canted to windward. Good for racing, not such a good idea for
> > > cruising (Sail force increases as the boat heels) or light air (sail
> > falls
> > > to ww). The 15m in the shed at the moment has a canting/raking rig. will
> > > be interesting to see how it works out.
> > >
> > > rob
> > >
> > > On Fri, Sep 16, 2011 at 12:09 PM, tsstproa <bitme1234@> wrote:
> > >
> > > > **
> > > >
> > > >
> > > > Hey Rob this is what I meant have a look in photo's under forces at
> > play
> > > > just a thought the vertical lines show rotation due to precanting.
> > > >
> > > > Some might say INDUCED positive / negative for anticipation of.
> > > >
> > > > Todd
> > > >
> > > >
> > > >
> > >
> >
> >
> >
>