Here's a question you might get in a seamanship exam.

You are sailing a 32ft catamaran along the Pacific coast of Mexico, and are now well into the Gulf of Tehuantepec, keeping close to shore, as the books insist you should. At dusk the light NE wind becomes a strong north westerly, so the swell, instead of being off shore, begins to run parallel to the coast. There is no moon, thus when night falls it is pitch black. Although you can't see it, you know you are close to shore, for the boat is being hit by spray, blown back by the waves breaking on the beach. The nearest safe harbour is 80 miles away.

Do you:

a) Anchor? However you will be anchored less than 100ft from the shore, and will have to spend the night just outside the surf line, pitching and rolling in a big cross swell.

b) Carry on sailing close to the beach? But there's an unmarked reef ahead, and you have already passed inshore of several large sunken trees, left-overs from Hurricane Stan.

c) Get some sea room?

We chose c) Which was the wrong answer.

But at the time it seemed the seamanlike thing to do, so we began to sail further out to sea. Less than an hour later the wind picked up to over 30 knots on the nose.

So another exam question:

You've already been sailing for four days in very changeable weather and had little sleep. There is plenty of sea-room and no shipping, so do you now:

a) Stop sailing until dawn?

b) Carry on? Even though it would mean hand steering all night. It also means you will be very tired next day, when you will have to not only enter a strange harbour, but also deal with the notoriously complex Mexican immigration procedures.

We chose a) Another wrong answer.

Crossing Biscay during a November gale we had been able to sail Eclipse to windward, while sitting inside, steering using the autopilot remote control. In another gale off the Caribbean coast of Nicaragua, we ran before the wind. In May last year I helped sail a 35ft Banshee catamaran down Channel. The SW wind held steady at over 40 knots for several hours as we beat into 5m high waves round Portland Bill. But these were all "yachtsman gales"; now we were to face something very different.

There are 3 proven techniques for riding out bad weather. Lie ahull, run before, or lie to a parachute sea anchor. The first two would have meant drifting downwind and further away from our destination, so we decided to deploy our parachute sea anchor.

Parachute sea anchors

I bought mine when I raced in the 1987 AZAB on a Banshee. When I had practiced using it in winds of 35 knots and moderate waves I had been very impressed as to how quietly the boat lay; however this was to be the first time it had ever been used in anger. Nigel Irens told me that he had once damaged his trimaran's rudder as it was swept backwards when lying to a sea anchor, so first I made sure that Eclipse's were centered and well lashed. It then took some fiddling to set up the parachute bridles so that Eclipse would stay bow on to waves, but once I was satisfied, we went below for the night.

The sketch also shows the swivel between parachute and warp which stops the warp twisting up, and the fender. This not only indicates the parachute's position, but more importantly keeps it near the surface. Some people deploy fenders that are too small, you need at least 35 kgs of buoyancy, or something like a 1m long fender.

Looking back, that first night was actually OK, even though the wind and waves built up steadily; by next morning the wind was probably around 45 knots and the waves 3-4m high. Eclipse was being pulled up and over, indeed often right through, the steepest waves. As the day wore on the wind kept on increasing, while the waves, which by mid morning were around 4 - 5m high, remained very short and steep. Most had big breaking crests which looked more like those seen on a surf beach than what one might expect offshore. So the sketch accompanying my PBO article was misleading as that showed 15m high waves 70m apart - in the worst of the storm we actually experienced 6-9m waves 30m apart.

Not surprisingly, by now there were huge loads both on the 25mm main warp and also on the bridles. Maybe the 50m of warp I had let out wasn't enough, but it proved totally impractical to lengthen it in those conditions. Anyway, conventional wisdom is to have the parachute in the next wave train, which is what we had.

Eclipse was being washed backwards in the biggest waves, which was not really surprising, as when I went onto the foredeck I could see that Eclipse was coming clear out of the water back to the mast. Worse, we were surging to and fro and swinging nearly broad-side to the waves. Clearly something had to give, there was just too much load. Finally first one and then the other bridle broke. I used the main anchor warp to make up new bridles because they helped spread the loads and prevented some of the swinging. Mind you, it was hard work tying knots on a foredeck which was alternately going underwater and then leaping 3m into the air!

Our parachute was about 3.5m diameter. In hindsight I should have bought a bigger one. Jim Duerden of Top Cat Cruising has experimented with different parachute sizes. He found that while 3.5m diameter was OK for a narrow beam 9.5m catamaran, when he tried it on a wide beam 11m catamaran it surged around just as Eclipse did. He later changed to a 5.5m diameter chute and solved the problem. Bigger might be better, but of course everything costs money, and, even for safety gear, that's always limited (you're looking at around GBP1000 for a 6m chute and 100m warp).

However it's clear that even between the major manufacturers there is disagreement about the correct size of sea anchor. For example, for a 32ft/5 ton boat Paratech, (www.seaanchor.com) recommend 3.6m, while Fiorentino, (www.paraanchor.com), recommend a 2.7m diameter. Still others say 6m.

Both suppliers and users also have different opinions about warp and bridle lengths. Some recommend a main warp as thin as 12mm (our broken bridles were this diameter), some say use 30m long bridles, but most say use bridles about the length of the boat - which is what we did. Some people have said you can make a sea anchor from a storm jib - but I doubt that you could actually rig it up during a storm and anyway, I don't think it would work. Even our 3.5m diameter parachute had an area of about 12 sq m, much more than our 5sq m storm jib.

As is now well known, our parachute eventually broke. Although 20 years old it was heavily made, and certainly stronger than others I've looked at. Even so, when I pulled the remnants in I found some of the canopy lines had pulled out and the top had shredded.

Running Before

We were no longer able to stay bows on to the weather, so we now tried running before the waves. Bernard Moitessier said one should do this as fast as possible to ensure that the boat keeps ahead of any overtaking waves. That's what the Smeetons tried, but they famously pitchpoled, not once, but twice. Robin Knox Johnston has said that Suhali was too slow to be really safe in the Roaring Forties.

Although Eclipse is directionally stable and has regularly surfed at 16 knots, high speeds are only safe when running before a big swell which has long wave lengths. More usually one needs to sail slowly.

To do this one uses drogues; it doesn't really matter how sophisticated they are, they just need to slow the boat. Fortunately I had already prepared warps to stream from the stern for just this eventuality. I led one to each genoa winch so that it would be easy to adjust their lengths. It only took a few minutes to deploy them, and then later, to slow us down from 6 knots to 4, I added the remains of the parachute and its warp.

Again, running before a storm towing warps was a new experience for me. I found Eclipse very heavy to steer, Jetti wasn't strong enough. Clearly I at least would have to stay outside - we couldn't use the autopilot because we needed to avoid the waves ahead.

However it was immediately obvious that running before these very steep, high waves wasn't safe. Had we gone "over the edge" it would have been like falling down a waterfall, and no boat could survive that. So we had to sail slower than the waves, which meant that the breaking waves overtook us. The first wave splashed into the cockpit, but the second was much bigger and washed over the whole boat. It filled our dinghy - which we carry in davits - so we had to cut it free and thus lost it. Some water even got below to wet the carpet. We couldn't continue like that, so now we had only lying ahull as an option.

Lying ahull

Lying ahull means that not only does the hull structure get battered by the breaking waves, but more importantly, the boat will lie broadside to the approaching waves.

For 15 years I have been the "Multihull Expert", sitting on the international "Stability and Buoyancy" committee that has been defining stability standards, in part for the RCD. Thus I know that, unless the wave height exceeds the boat's beam, a boat is safe when lying beam-on to steep, breaking waves. When such waves exceed the beam then there is a risk of a monohull being knocked down or of capsizing a multihull.

So we cautiously luffed Eclipse and lashed the rudders to lee. We streamed the warps off the windward stern, my idea being that, when a wave hit, with the daggerboards raised, the bows would be pushed to lee while the drogues would keep the boat moving in a constant direction. The waves were now averaging 6-8m high, however Eclipse has a 6m beam, so to start with, at least, we would be safe.

Unfortunately, statistics show that one in every 1000 waves is twice the average height. If a wave passes every 30 seconds then that extra high wave occurs about once every 8 hours. In total we were 28 hours at the mercy of the storm, so were certainly pushing our luck. Maybe a little learning is a dangerous thing, but knowing the statistics was a major reason for deciding our lives were in danger.

Despite Eclipse being undamaged and upright, we called a Mayday. Ten hours later we were picked up by a helicopter from USS Ford.

Conclusions

Had the wind been "only" a steady 45-50 knots we would have had no problems. But it was very much more than that. Indeed the helicopter pilot reported flying at 50 knots just to keep station and going up and down 6m to stay a constant height above the waves. That's at least F10. Even so, we thought that the weather had improved significantly since earlier in the day.

So how windy was it at its worst? I don't know; our Raymarine ST40 refused to read more than 32 knots. But I do know that my face was distorted by the wind and that I couldn't stand up without holding on. At one stage the whole sea turned white - so was that F10-11, 60 knots - or more?

It was very sad to lose Eclipse. Fast, comfortable and safe, Eclipse had been our home for 5 years. But we are still alive and eager to build and cruise another catamaran.