20170131

In the past few days I put together a sail plan for Hatseflats.

It shows the Tirrik sail with the luff vertical and mast rake at 3 degrees. The mast position is just behind the mast bulkhead @1200. Mast diameter is 1/56 of its length. Yard and boom are 1/50 of their lengths.

The total area of the daggerboard is 4.5% of the sail area. This is in line with PD racer practice, but above the 3.5% which is used for sailing yachts. Since I wanted a max draft is 75cm, the chord length of the daggerboard is about 50cm. Its CofE is directly below the CofE of the sail. I should move it forward about 6-7cm to ensure that we have slightly more weather helm.

The draft of the rudder is 60cm. Chord length is 25cm. Its area is about 1.6% of the sail area. It is also about 35% of the daggerboard area.