• The Volvo Ocean Race – crewed boats, multiple legs, fixed schedule.
• The Vendée Globe – singlehanded, fixed schedule. No pit stops allowed, but competitors can restart during the first few days.
• Singlehanded Round The World Record – competitor chooses start date. No pit stops allowed.

Competitors are now showing their form, and the potential winners have three things in common:

• The shore teams have superb project management and quality control. They have had time to make sure everything works and they have checked everything that can be checked.
• The skippers and crews are in control. They have put in enough sailing time under enough different conditions, and against benchmark competitors, to be confident that they know how to get the best out of their boats under all weather conditions.
• The skippers have the self-discipline and stamina to set whatever pace seems necessary to give them a good chance of winning.

Of course, even perfect preparation and an ‘ice man’ skipper is still no guarantee of winning. Ocean weather and sea state are chaotic systems, and freak conditions occur. The sea contains a liberal scattering of things to bump into, trip over or get tangled up in. At best they slow you down until you cut them adrift, but at worst they  can do serious damage and even put you out of the race. Both the Volvo and the Vendée have already had their fair share of such incidents.

In the Volvo, Torben Grael and Ericsson 4 are clearly the best-prepared and most experienced team, which has allowed them to drive harder than anyone else, even maintaining a lead in the first leg in spite of having to drop off an injured crew member who was one of their two ace helmsmen.

The Vendée Globe is particularly exciting because several boat/skipper teams appear to have what it takes to win. Mike Golding tried too hard, misjudged the start and had to return. Michel Desjoyeaux’ shore team missed a trick and allowed him to start the race with a problem that meant he had to return, restarting more than a day late. But both of them sailed so fast that they are now among the leaders.

Loïc Peyron lead the Vendée fleet on the wy to the Indian Ocean for about a week, but suddenly lost his mast during the next phase without knowing why. Did the shore team miss a trick somewhere? He’s not the only one to lose a mast or suffer rig failure, but because of his reputation and that of the Gitana Eighty team, everyone is surprised.

As for Thomas Coville and Sodeb’O, I find them both fascinating to watch. Coville goes about his job as if he were skippering a flotilla cruise, chatting to the press over his shoulder as he flings a small sports bag aboard and casts off. Even with Sodeb’O porpoising uncomfortably in the short inshore swell as he set out, he looks as if he’s walking on dry land as he moves around. I’d love to see some video footage of Sodeb’O in the southern ocean…

Rigs have probably been the weakest link in seagoing vessels since the earliest days, and the first two days of Vendée Globe 2008 have been no exception. There’s a good reason for this: if you over-engineer the rig, the increased weight reduces stability, and hence the ability to carry sail. The Ocean 60 class rules take this into account by including a stability test, so the challenge is to produce a tall, strong rig for the minimum possible weight.

The stress analysis challenges are like those for civil engineering structures such as viaducts, only more complex. It’s easy to calculate the static loads, but what really matters in civil engineering structures is the resonances caused either by traffic or by high winds. Victorian engineering is littered with examples of failures caused by not understanding or being able to assess this. The damping effect of having a sail attached to it makes it a far less common concern for a mast, but there is a far more serious problem which viaduct designers don’t have to cope with.

Masts are attached to boats, and when the sea gets rough boats leap half out of the water and come crashing down – sometimes into a wave that is coming up to meet them, and possibly knocking them sideways at the same time. That’s what smashed masts in the Bay of Biscay this year, often after the wind had abated significantly.

Places like Southampton University’s Wolfson Unit are now highly skilled at using tank tests to assess the stresses on hulls, and modelling the way they react to those stresses. I don’t know of any group that has made similar progress in calculating the stresses on masts while attached to a freely moving boat. The number of degrees of freedom involved make for pretty computationally-intensive mathematical modelling, and the problem sounds too chaotic to model physically in a tank. How do you reproduce the kind of sea that builds up when strong winds shift through 90 degrees?

Racing in extreme classes like the Ocean 60 has helped collect the data that has led to class rules and  international standards, for hull construction and materials. I would expect it to contribute to similar standards for rigs at some future date. Certainly examination of the failures that have occurred in recent years will establish what probably caused them, but I don’t know of any boat carrying recording instruments that could give an idea of the actual stresses that occurred in specific incidents.

For instance, does any boat carry an accelerometer? Many years ago, offshore powerboats suffered serious damage without even hitting solid objects in the water.  In one case, a heat exchanger broke off and went through the bottom of the boat when it landed after jumping off a wave, and in another, one crewman finished a race with compression  fractures in both legs.

If there is anyone reading this who can point me in the direction of research being done on stresses on rigs in rough seas, I’ll be very grateful. It’s well beyond my own mathematical and computational skills, but I’d still like to read about it.

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