DESCRIPTION f*

RIG FOR SAILING CRAFT

The field of art of this invention is the field of ship sub class; marine propulsion, acted on wind.

Background art: To minimise the heeling force is of great advantage in sailing. To attain this, the line of the 5 sailforce has to be directed close to the hull's centre of lateral resistance and the sail's centre of effort has to be moved out to leeward. Conventional rigging does not allow for these sail positions. Various attempts have been made at achieving this. The following specifications were 10 published by the Australian Patent Office:

AU - Al - 43,601/79 58,582/80

74,842/81 10,032/83

21,817/83 For practical results the craft has to be able to sail 15 at all points of sailing, requiring a great flexibility of sail-positions with simplified controls, not fully achieved previously. The object of this invention is to provide such practical results.

Fig. 1. is the view of the rig. 20 Fig. 2. is the control to change the angle between the spar and the mast. The following is the description of the best mode of implementing the invention with reference to the drawings: A sail 1 extended from a spar 2 and kept taut by a 25 suitably shaped boom 3.

The spar 2 is pivotally 4 attached to the top of a mast 5. The mast is firmly attached to the hull. The pivot 4 allows the spar to rotate around the attachment pivot in any direction. 30 The position of the attachment position 7 on the spar is important. It has to be higher than the sail's centre of effort. Too high a position, for example, on the top of the spar is not practical because it necessitates a taller mast and the foot of the sail would swing out too far. _^ - _" tT E

O P

- Z -

Pole 6 is to control the angle between the spar and the mast. In Fig. 2. the pole 6 is pivotally attached to the spar"2. The pole goes through a guide 9 which is attached to a ring 10, this ring is able to revolve around the mast. Thus the pole can slide close to the mast and also revolve around the mast. Pulling control line 11 slides the pole towards the spar and increases the angle between the spar and the mast.

In gentle winds the pole is not extended, the craft can be sailed as a conventional sailboat controlling the sail by the main sheet 12.

In strong winds control line 11 is pulled and cleated. This sets the angle between the spar and the mast. The sail tends to swing forward, line 13 and pole 6 stop the forward movement. Line 13 controls the fore and aft swing of the sail thus the directional balance; the main sheet 12 sets sail's angle of attack. By setting a proper angle of the spar, the line of the sailforce can be directed close to the hull's lateral : resistance. To tack, line 13 is pulled, the sail will pivot to aft, creating a strong weather-helm and assisting the rudder to turn the craft into and across the wind, the sail's camber is reversed, and as soon as the sail draws wind, the sail swings forward on the other tack. The pole 6 rotating around the mast keeps the same spar-mast angle which was set by line 11.

The rig is constructed using conventional materials. Depending on size, it will be necessary to stay the mast under ring 10 and reinforce the unstayed top of the mast.