CHAPTER 17 Getting off under sail
Grounding when heeled well over Conventional fin keels When beating up a narrow channel that shoals near its edges it’s important to remember that a yacht with a conventional fin keel draws less water when heeled over. If she grounds near the end of a tack, her plight is exacerbated as she comes upright. Other keel configurations Rather than decreasing their draught, some keel configurations actually draw more water in the heeled condition than they do upright. These, notably, are wing keels and bilge keels, both of which
are used in significant numbers of yachts. If one of these grounds in the heeled condition, she has every chance of floating off again if she spills wind or drops her sails.
Extreme measures to reduce draught
Lee and weather shores Lee shore To ground on a lee shore is among the worst-case scenarios for any sailing vessel. It was the biggest cause of total loss in the days of commercial sail. Unless the wind is well abaft the beam, any boat propelled by canvas slides to leeward as she gathers enough way to steer from a standstill. For a boat on a lee shore, any attempt to sail off is therefore doomed to failure. It may be possible to shove a very light craft far enough off to surmount this rule, but once the grip of the mud on the keel is added to the equation, sailing out of the dilemma becomes a non-starter. Aground on a lee shore, the first action is to drop the sails and start the engine if one is fitted. If not, the only answer is to haul off, either by laying out a kedge or by some alternative ruse for pulling the boat into deep water. Weather shore Because the wind is blowing off the weather shore, a grounded sailing yacht sliding to leeward as she tries to gather way is doing herself nothing but good. Any leeway will take her into deeper water, which opens up various courses of action:
To anchor or rescue vessel
Increasing heel Dropping sail should not be the first reaction to grounding on a weather shore. Sometimes a conventional monohull can literally be ‘heeled off’ by pulling the sheets in hard to increase the effect of the wind. Adding the movement of body weight, etc, may just give a vital final inch or two of reduced draught. Extreme heel In severe cases, a boat can be made to heel to a dramatic degree by laying out a kedge (or securing to a fixed object well away from the boat), then leading the warp to a spare halyard. A spinnaker halyard is favoured because it is rigged from a swivel and can accept pull from any direction, but if all you have is an extra jib halyard, use this. Lay the kedge as far to seaward as you are able, set the anchor with a good heave from deck level, then attach the halyard and start winching the boat down. Not only does this substantially reduce the draught of a simple deep-keeled yacht, it also encourages the keel to ‘skip’ along the bottom rather than drudge through the seabed as it does when the pull is from nearer deck level. It’s not pretty and it can be downright alarming, but it’s as near to being a sure-fire winner as you’ll get. The technique can be equally useful on a lee shore, but it’s unlikely to work with a bilge keeler or a yacht with any sort of ‘plate’ at the bottom of the keel.
MANUAL OF SEAMANSHIP | 147
Grounding
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