Thursday, 22 July 2021

An English Summer 49


 In the calm before today's (and tomorrow's) summer blow (with the wind forecast to peak at forty knots) a six oared gig, rows past, lit by the glow of the setting sun. A craft shaped by the particular demands of these waters. Evolved from the requirement to put a pilot aboard a wind-jammer, in from the Atlantic, in all weathers, all sea states . First. To enable the pilot to make a living.

Peter Martin and Alfie Hicks, of Pettifox fame, built her in the Porthloo shed now run by Andrew Hicks.

They built the Alfie Jenkins too, housed among the dunes, in Bryher's 'Sussex' gig shed. (The plaque explains the shed’s name, if you zoom in). Out of the reach of the highest storm tide. The boat named in memory of a man, who did more than most, to put Scilly at the centre of the worldwide gig rowing revival.

There is no truly all weather port or anchorage, in the archipelago. The gig was therefore developed to keep the seas; but take to the shore, when shelter was required.

It is oft said, that all boat design is a compromise. Stargazer, with her one point eight metre fin keel and forty percent ballast ratio, can carry sail, to windward, in all bar storm conditions. But, on Scilly, her opportunities for shelter are limited, by her draft. Today we are in New Grimsby Sound, with the cliffs of Tresco between us and the wind. Deep draft craft are running in, from more exposed anchorages, for shelter. 

This morning I took Stargazer on a two mile circuit, of the sound. Seeking out enough unoccupied depth, to re-anchor. This, after making the unwelcome, but timely, discovery that, with the wind now firmly in the east, Stargazer was lying over a shoal patch. As she swung, in an arc, around her anchor, the depth reading would suddenly drop and then recover. In these waters that translates into a rock, lurking below. Today we had point two of a metre clearance. But with the tides getting bigger, as we head toward Monday's springs (low lows and high highs), insufficient to float us from tomorrow onward, at the forecast height of the blow. It was time to move.

In Scilly, options for shelter multiply if a boat is able to take the ground, or to float in very shallow water. Green Bay, on Bryher, for example, dries almost completely at low water. Today it is filled with the whole gamut of shoal draft designs, with more still arriving.

Catamarans will float in knee high waters, or happily dry out, on the beach. Most, however, will not sail effectively to windward, having only stub keels with which to resist leeway (being blown sideways) and high cabin tops, which worsen matters. A tradeoff suffered by this homely Hirondelle, which we last met, high and dry, on her mud berth in Porth Navas creek, on the Helford river.

Some cats do sail effectively to windward. This one has dagger boards, as well as flush decks, to counter leeway. Gaining upwind ability, at the expense of accommodation space below.

But she speeds along, even in light airs. In a breeze, she would fly. . . .and so, I suspect, would the spray. One for the dedicated enthusiast, perhaps.

Monohulls too, can take to the beach, if they have lifting keels like this Southerly. She has the same ballast ratio as Stargazer: forty percent. But less than ten percent, of that, is carried in the keel. The majority is higher up, forming a 'grounding plate,' in the bottom of the bilge. The leverage of that ballast is reduced, compared to Stargazer's, whose keel bulb is almost two metres beneath the surface of the water. The Southerly's upwind sail carrying capacity is, therefore, less than that of a fin keeler. But she will float in point seven of a metre of water and happily dry out upright. An advantage, on a day like today, where available anchoring space is limited and shallow.

Bilge keelers lie somewhere between lift keelers and fins, in terms of draft, righting moment and windward ability. Although their extra underwater appendage adds drag, it also enables them to stand,, on their own two feet, ashore. For every pro a con, in boat design.

The permutations are as varied as the waters, on which boats sail; and the priorities of the folk, who sail aboard them.

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