GB2294666A - Sail Boats. - Google Patents

Abstract

A sail boat having a hull 2 and a mast 3 for supporting at least one sail, the mast 3 being supported by an electrically conductive fore-stay 5, characterised in that the fore-stay 5 is secured to the hull 2 by an electrically conductive bow-piece 6 attached to the hull 2 and which extends downwardly substantially to the waterline 7 of the hull. The mast which is preferably of carbon-fibre is additionally supported by electrically conductive shrouds 8 and back-stays 9 which terminate in metal plates 10. The arrangement serves to prevent or reduce the damage caused by a lightning strike. <IMAGE>

Description

TITLE: SAIL BOATS DESCRIPTION The invention relates to sail boats and more particularly, but not exclusively, to sail boats of the nature of ocean-going yachts.

It is an object of the invention to improve the safety of sail boats generally. More particularly, it is an object of the invention to improve the safety of sail boats in the event of lightning strikes.

According to the invention, a sail boat has an electrically conductive fore-stay secured to an electrically conductive bow-piece which extends downwardly substantially to the waterline. Preferably the bow-piece extends substantially below the waterline.

The bow-piece may be in the form of a fairing made of a material such as stainless steel. Preferably the bow fairing is readily detachable for replacement in the event of collision or other damage.

Preferably the mast has shrouds and/or back stays which are also electrically conductive and which are terminated on the hull by electrically conductive plates arranged at or adjacent to the waterline.

Preferably the mast of the vessel is of carbon fibre or the like so that its electrical conductivity is relatively poor compared to the said shrouds and stays.

The shrouds and stays may be metal rods. In this way the shrouds and stays together form a rudimentary Faraday cage to protect the vessel in the event of lightning strike.

The invention is diagrammatically illustrated, by way of example, in the accompanying drawings in which: Figure 1 is a side elevation of a yacht; Figure 2 is a sectional end view of the yacht of Figure 1; Figure 3 is a scrap sectional view, to an enlarged scale, of a detail shown ringed in Figure 2, and Figure 4 is a rear view of the yacht of Figure 1.

In the drawings there is shown a yacht 1 having a hull 2 having a bow 13 and a stern 14 and a mast 3 e.g. of carbon fibre composite, on which is articulated a boom 4 for controlling a sail (not shown). In generally conventional fashion the hull is formed with a downwardly depending keel 11, a steering rudder 12 and a propeller 16 e.g. for use in manoeuvring the vessel in harbour and other confined spaces. The normal waterline of the yacht is shown by dotted line 7.

The mast 3 is supported by a fore-stay 5, shrouds 8, i.e. side-stays, and by back-stays 9 which, in conventional fashion are secured at their upper ends to the mast 3 adjacent to its top (not shown). The stays 5,8 and 9 are electrically conductive and may be in the form of metal, e.g. steel, rods.

The bow 13 of the yacht is enclosed by a stainless steel fairing 6 detachably secured to the hull and which forms a bow piece extending from the level of the deck 17 to the bottom 18 of the hull 2, i.e. to below the waterline 7.

The lower end of the fore-stay 5 is secured to the bowpiece 6 at 18, i.e. substantially at deck level in any convenient fashion but so as to be electrically connected to the bowpiece which in turn is electrically connected to the water in which the yacht is sailing.

The lower ends of the shrouds 8 and back-stay 9 pass down through the deck 17 of the hull 2 and are attached to the hull below the waterline 7 by means of plates 10, e.g.

of stainless steel on the outside of the hull 2 and to which are attached fixing lugs 15 which penetrate through the hull and which carry pins 19 which engage in eyes (not shown) in the lower ends of the stays 8,9.

The stays 5,8,9 thus form a simple cage enclosing the mast and provide an easy path to earth for lightning to prevent or reduce the damage caused by lightning passing down the mast and/or stays and through the hull to earth.

Also the bow fairing 6 not only reinforces the vulnerable bow of the yacht but is arranged to be readily detachable from the hull 2 for replacement in the event of damage.

The invention thus provides simple means for mitigating the effects of lightning strike.

Claims (7)

1. A sail boat having a hull and a mast for supporting at least one sail, the mast being supported by an electrically conductive fore-stay, characterised in that the fore-stay is secured to the hull by an electrically conductive bowpiece attached to the hull and which extends downwardly substantially to the waterline of the hull.

2. A sail boat according to claim 1, characterised in that the bow-piece extends below the waterline.

3. A sail boat according to claim 1 or claim 2, characterised in that the bow-piece is in the form of a fairing made of stainless steel.

4. A sail boat according to any preceding claim, characterised in that the bow piece is adapted to be detachable from the hull for replacement in the event of damage.

5. A sail boat according to any preceding claim, characterised in that the mast is supported by shrouds and by back stays which are electrically conductive and which are terminated on the hull by electrically conductive plates arranged at or adjacent to the waterline.

6. A sail boat according to any preceding claim, characterised in that the mast of the boat is of carbon fibre or the like construction so that its electrical conductivity is relatively poor compared to that of the forestay.

7. A sail boat substantially as hereinbefore described with reference to, and as illustrated in, the accompanying