Sunday, May 31, 2015

Driving force at different sheet angles for various angles of Incidence. Omega 14 sailboat.

So what is remarkable about this?   I'm not sure.  If this is correct you wouldn't be hurt too much if you simply left the car for the jib sheet an inch or so forward of middle of the track on the omega.  The thing that always makes these theoretical ideas somewhat dubious is that the design of the sail, the tension on the halyard and even the sea state influence the optimum conditions for sail trim. It is much more prudent to look at how the tell-tails are flying and the slot between the main and the jib before considering moving the fair-lead for the jib.

Home made hiking strap hardware

When I added my Barney Post I had to figure out how to attach my hiking straps.  A small piece of PVC pipe from the scrap pile worked just fine.  I sanded the sharp edges and made it a bit shorter than shown in the sketch just fit the width of the strap.

OPTIMUM BOOM ANGLE

If a man will begin with certainties, he shall end in doubts, but if he will be content to begin with doubts, he shall end in certainties.
I don't know who said that, but he may have been talking about sail trim.  I have studied the subject and now have more doubts than I started with.  C.A. Marchaj wrote a definitive book about sailing theory and relates boom angle to wind speed.  Of course the most important thing is the angle of the sail to the wind and that also depends on things like leech tension. Nevertheless, for what it is worth I made a graph that I consider a starting point for positioning the boom on the Omega 14.
I would love to hear other people's opinion.
Bear in mind that boats differ and I know that some classes center the boom whenever they can.

ISOMETRIC DRAWING OMEGA 14