| At sea. Clipper Race: The apparent truth |
|
|
|
| Friday, 02 December 2005 | |
|
Event media: To spinnaker or not to spinnaker – that is the question. Over the last 12 hours the winds have abated slightly, which will allow the fleet to have a bit of a breather before the next blow comes in. The picture shows Western Australia well heeled over under their medium weight spinnaker, and gives a good idea of how powerful these sails can be. As the wind increases, the lightweight, 0.75oz, spinnaker is peeled to the medium weight (1.5 oz) when there is about 12 knots of wind over the deck, then to the heavyweight (2.2 oz) when the wind gets to the high teens. Once the apparent wind reaches the mid twenties, the point at which the spinnaker is dropped depends on the sea state and the skill of the helmsman and the trimmers. Apparent wind (wind over the deck) is the wind that you actually feel on board, and is the combination of what the wind is actually doing (true wind) and how you are moving through it. As an example, consider an open-top car moving at 30 miles per hour on a hot, still summer’s day. The true wind is zero, but your hair style will have to cope with 30 miles an hour of apparent wind. When running into the wind it feels much more, as the apparent wind is the sum of the true wind and your (perhaps ever-decreasing) speed into it. However, when you turn the corner and run with the wind it feels much less, as the apparent wind is now the difference between the true wind speed and your speed. So, going back to spinnakers, this is the whole crux of the question as to whether to fly it or not. When the boats are fully powered up under heavyweight kite at the top end of the range they will be going at about 12-15 knots, with about 20-25 knots apparent wind. Doing the sums, therefore, means that the true wind speed is anywhere from 32 to 40 knots, in other words a near gale force 7 to the top end of a gale force 8. Should anything untoward occur, this amount of wind can turn a perfectly trimmed spinnaker into a tangled, tennis court sized nightmare. So the skippers and watch leaders will be continually assessing the situation, and hoping that the wind will either drop marginally, for more control, or increase so as to make the decision for them! Over the last 24 hours the lateral positions have stayed fairly constant with the exception of second-placed Glasgow who are now the most southerly boat (penguin hunting, as Graeme Johnston explained). Durban have extended their lead slightly and have also slowly moved to the southern flank of the fleet, leading a loose southern pack of Jersey, New York, Victoria and Glasgow. The northern group is currently being lead by Cardiff Clipper who have moved through the pack quite emphatically overnight, averaging 10 knots over the 12 hours. Singapore, with duty skipper Richard Falk, are also making good progress, with an overnight run of 119 miles. www.clipper-ventures.co.uk |
|
| Last Updated ( Friday, 02 December 2005 ) |
| < Prev | Next > |
|---|