In the first article I explored some of the differences between multis and monohulls with regard to safety issues. Now we take a look at the worst-nightmare scenario, capsize, on the basis that being prepared for the worst means having confidence when things start to get rough.
First the reality check…
I do not want this article to give the impression that the risk of unrecoverable capsize makes multihulls inherently dangerous, because in truth most multis are incredibly safe and stable, and the risk is certainly no greater than that of sinking for monohulls. There are thankfully very few reports of capsizes, and the vast majority of them occur to racing craft. In recent years even the diehard monohull fraternity have stopped referring to cruising multihulls as being ‘on the knife-edge of disaster’. Advances in design have made our boats safer and more stable, but it is still possible to capsize them, especially racing craft and the more powerfully-rigged fast cruising boats. For that reason we should think about what to do to avoid the risk, how to tackle an immediate threat and how to cope with the aftermath.
Making sure it doesn’t happen
Capsizing is the one thing guaranteed to spoil your day. For racers it might be a risk worth running, but for cruisers it is catastrophic. For this reason many production boats are designed with modest rigs. But it is not the wind alone that tips you over, it is a combination of wind and waves. A multihull cannot spill wind in the same way that a mono can, by heeling, and will just accelerate in a big gust. This makes it more vulnerable to wave action. If a big steep wave gets underneath a catamaran’s windward hull, it is lifted, causing the centre of gravity to shift towards the leeward hull. If the windward hull continues to rise right out of the water, the boat can eventually pass the point of no return, around 70 degrees, rotating around the leeward hull. Normally the boat will be pushed sideways and side-slip safely down the face of the wave. If the lee hull has a daggerboard gripping the water, lateral resistance works against you and can ‘trip’ the boat up. Hence the advice to raise the lee daggerboard in marginal conditions. A trimaran has to lift two hulls before going over sideways, so tends to give more notice of problems and is able to heel to a greater angle before reaching the point of vanishing stability. Most multihullers instinctively recognise the dangerous sea conditions that might put the boat at risk of capsize, take early action and avoid placing the boat at a vulnerable angle to the waves.
The above scenario assumes a huge gust on a reach in marginal conditions, but another dangerous angle is when the boat is surfing downwind at speed and pitchpoles diagonally over the lee bow. This occurs when the bow is stuffed into the back of a wave and is held down by the weight of water while the rig’s effort, centred much higher, drives the back of the boat up and over. Some designers make much of the importance of ensuring there is adequate buoyancy and a water-shedding shape at the bows so that they can lift themselves over waves rather than ‘submarining’ through them. It is also the reason why trampoline nets are preferable to solid front decks.
All this sounds like scary stuff, but in reality most cruising sailors will have started to take avoiding action long before a crisis is reached. Flying a hull (or two) is something I wouldn’t even contemplate, and any sign of this would be an instant signal to reef down and sail more cautiously. I tend to think of multihulls as the sports cars of the sailing world. You wouldn’t drive one of those around everywhere at top speed, and nor should a multi be treated as such. In contrast, monohulls often need to be sailed at maximum speed, and can tolerate being over-canvassed in a gust because they heel and spill wind. Beware the sailor who thinks multis can be sailed in the same fashion!
In high winds or very gusty conditions one should always ensure that sheets and traveller can be released instantly. In the past some people have experimented with auto-release systems, where a cleat gives way at a certain level of load on the sheet, but these have fallen out of favour because of unexpected releases and unreliability. Perhaps such systems may get developed again using computer control, but it is likely they would only be the preserve of the superyacht.
Things to do when the wind pipes up
· Reef early. If you think about it, do it then not later. Reef to the gusts not the average windspeed. Know what windspeeds your various sail combinations are good for.
· Sail conservatively with regard to the sea state. Manoeuvre between big waves.
· Ensure that sheets and traveller can be released quickly in an emergency. Carry a knife in case they jam.
· Look ahead. If you see rough water, there may be a lot of wind round that headland or barrelling down that valley.
· Raise daggerboards in order to side-slip. Pulling up the lee daggerboard reduces the possibility of tripping over the lee hull.
· Slow the boat down if she starts to surf uncontrollably.
· Take personal precautions – lifejacket, harness etc. Clip on!
Tactics for survival
Going way beyond the issue of avoiding risky scenarios during normal cruising, there is the matter of what to do in a survival situation. As the wind and sea build, one is likely to adopt a number of different tactics. The late Hal Roth suggested five stages: Deep reefing, heaving-to, lying a-hull, running off and deploying a sea anchor or drogue. Lying a-hull is possibly the multihuller’s least favoured option, and most multis would go straight to the running off stage.
For this article I am just going to look at sea anchors and drogues. Some sailors have nothing but praise for sea anchors, some think they are dreadful. Drogues and sea anchors had a bad name for many years, arising from confusion between the small diameter ‘Admiralty-pattern’ drogues (which were unhelpfully called ‘sea anchors’) with the proper boat-stoppers, such as the modern para-anchors, usually 12ft or more in diameter.
Modern sea anchors are large parachute-shaped items made of heavy material. They are deployed off the bows on a bridle with a very long stretchy warp (200ft or more) that needs to be adjusted so the parachute sits in the same part of the corresponding wave as the boat. If this is not done the parachute may be pulled out of the wave while the boat is buried in it, leading to lots of snatching and jerking. The sea anchor’s bridle will be attached to the boat at very strong points because the loads are enormous and chafe is an ever-present problem. A modification to the boat is normally required to ensure that it is strong enough to take these loads. When large seas hit the boat it travels backwards, so the helm must be securely lashed to prevent damage to rudders. Reports from some storm survivors suggest that the sea anchor works well and allows the storm to pass over them very quickly. The boat faces into the weather, the best angle for protection. But Richard Woods, in his account (published in Multihull Review) of abandoning his catamaran Eclipse in the Gulf of Tehuantepec, found the sea anchor produced a horrendous motion and made things worse not better. Others have reported similar experiences. It is worth noting that Richard’s boat did not capsize in the storm, even when abandoned to its own devices without a sea-anchor at all. Perhaps lying a-hull is not so bad after all? Except that when Rose-Noelle lost her sea anchor and lay a-hull, she was flipped…
A drogue, by contrast, is deployed from the stern of the vessel, and is the obvious first step to take when running downwind becomes too uncontrollable and risky. Its purpose is to slow the boat down so that control can be maintained. The simplest drag devices are warps, often with an anchor attached to keep them submerged. Car tyres are not recommended because they can tend to skip over the surface of the water (but anything is better than nothing…). There are several commercially available drogues, such as the Seabrake, Galerider, Delta. They all do the same job with greater or less efficiency.
Perhaps the best type of drogue is the Jordan series drogue, named after its late designer Donald Jordan, who deliberately and generously did not patent the design. This is a very clever arrangement of small fabric cones distributed along a long stretchy warp. It has the advantage of always placing some cones in the same phase of the wave pattern as the boat, minimising snatch and jerks. They are commercially available as a kit or as a complete rig, but you can make one up yourself. The job is easy, if repetitive, and there are videos on YouTube to show you how. The great advantage of the series drogue is that will continue to function even after some of the cones have burst or come adrift and it makes best use of the elastic properties of a nylon warp. I have listed some hyperlinks at the end of the article for those who want to find out more, and hope to produce an article on my own experience of constructing and testing one.
Drogues are deployed on a stern bridle, again taken to very strong points such as winches. Adjusting the length of the bridle arms helps to position the boat at the most comfortable angle to the oncoming waves. Loads are not as great as those for sea anchors, and the boat continues to move forwards through the water, so there is no risk to the rudders.
Both sea anchors and drogues pose the problem of recovery. Although some people have used floating trip lines, these can potentially foul the drag device. Which means having to haul the boat up to the anchor or drogue to trip it manually. One technique – obviously after the worst of the weather has passed – is to motor out to one side before approaching the sea anchor. Drogues can have their line transferred to the bow to make hauling easier. Some commercial drogues have cunning ways to trip them and make them easier to recover.
Over she goes!
So – we have done our best to sail well and take defensive measures, but all to no avail. The boat is overwhelmed and capsizes. It is more stable upside-down, so it cannot be righted again at sea. What happens now?
First thing is to make sure all the crew are still on or in the boat. For those on top of the upturned boat, it is important that they should not get swept away. (We looked at personal kit for escaping from underneath the hull in the last article). They need a jackstay mounted underneath the bridgedeck to clip into, and the bridgedeck base should have non-slip paint all over, otherwise it will be a skating rink. Painting the underside of the bridgedeck bright orange would assist any search planes, or you could put ‘SOS’ or ‘OOPS!’ in big letters. Trimarans may well just have netting, which can at least be clipped into, and a rope tied over the main hull would make it possible to clip on while getting up onto a dry part of the boat.
People trapped inside should have enough air to breathe, but will need to be able to escape upwards, i.e. through the bottom of the boat, which is now the top. Production catamarans have hatches already positioned for this purpose, as required by EU law, but there is a problem with these. When the boat is right-way-up the escape hatches are just above the waterline – any lower and they would add unacceptable drag. But herein lies the dilemma: in the inverted position you need the escape hatch to be as high in the boat as possible to avoid water slopping in, and the production versions are rather low. Cutting an escape hatch through the bilge area is the answer, and this can be done in the optimum position, after capsize. Anyone caught outside the boat is unlikely to have the tools to achieve this, therefore there needs to be a well-secured locker (2 on a cat) positioned low down within the boat (in normal mode) containing tools that can be used to cut a hatch, i.e a hand drill, knife and hacksaw blades. The locker might also house other essential gear such as fishing lines and a solar still. (Let’s assume we are planning a long drift!) Where to put it? One possible location is underneath the bottom companionway step, where a triangular space might be sufficient to house the tools. An alternative is to place emergency tools in a sealed plastic flare container tied in to the boat.
Everything below in open-fronted lockers will fall out, or more likely get sucked out by the ebb and flow of water inside the hulls. Much of Rose-Noelle’s stuff was lost this way. Unfortunately most of us have such lockers on board – perhaps some could be modified to have door fronts, or netting at least? An early priority will be to salvage as much as possible, especially those things that could make life less uncomfortable before rescue, such as water, food and clothes. If they are already packed in sealed bags or containers, so much the better.
Ensuring there are some emergency water supplies is essential. The boat’s tanks are likely to empty or get seawater in them through the vent pipe, unless it can be shut off. I always like to carry a number of 2 litre soft drinks bottles stowed in various places around the boat. These are incredibly tough, and free, and their great virtue is that some could be lost without losing the whole quantity. Some cruisers carry jerrycans, others like the soft camping-type collapsible containers. Devising how to rig a raincatcher might be worth some thought, and the necessary materials included as part of the emergency pack.
On a monohull the emergency grab bag is equipped with the assumption that the boat will be abandoned. A multihull’s emergency bag should be equipped with items necessary for life on board the overturned boat. Vital documents will also be stored here to protect them from the water. And it needs to be attached to the boat so it does not get swept away.
Gas bottles will be upside-down, but should function. The ability to cook would be a great bonus and morale booster. Batteries might be salvaged and turned over to provide some power. They should, of course, be firmly strapped down, but there are some sealed batteries that have the capacity to be inverted and still function. Having some battery lights, an EPIRB, handheld GPS and VHF, even a mobile phone all charged and able to function independently means that loss of the house batteries will not disable all communications.
An Emergency Position Indicating Radio Beacon (EPIRB) is an amazing piece of kit, and should enable your position to be transmitted via satellite to a rescue centre within minutes. The manually-activated type might be best suited for multihulls, rather than the float-free type, so you can activate it when you are ready. A further refinement in an emergency would be to do a Tony Bullimore – when he was trapped inside the upturned hull of his racing boat, he switched the EPIRB off for a short period to let his rescuers know that he was still alive.
Sleeping might be a problem in an upturned hull. Finding a dry platform will be difficult, but it may be possible to use the underside of a bunk. One idea is to fix some metal eyes into the keel of the boat from which hammocks could be slung. This is handy because it is difficult to know how high the boat might float in the water.
How will she float upside down?
How the boat floats will depend on the buoyancy of the materials it is made from as well as any sealed compartments. It is an interesting mental exercise to translate the weight of the boat into cubic metres and to think where these will be found as buoyancy. What is the approximate volume of that watertight compartment? What volume would the composite hull skin occupy? Roughly how low or high in the water would the upturned boat float? Could the hull, or part of it, be sealed and pumped out? Even a single dry compartment would create some comfort. What would be needed to seal vents and apertures?
Going through the thought-exercise of imagining what life might be like in an inverted boat suggests a host of small modifications that would at least make things more comfortable and, in extremis, might just make the difference between life and death. I have mentioned a few ideas, there must be plenty more. I hope they may never be put into practice. But they will certainly help you to sleep soundly, knowing that you and your boat are prepared for the worst conditions and truly seaworthy.
Handling Storms at Sea: 5 secrets of heavy weather sailing by Hal Roth. £19.99 www.adlardcoles.com or nautical book supliers.
Articles by Richard Woods available on www.sailingcatamarans.com, including an account of abandoning Eclipse.
Chapter 6 of Adlard Coles’ Heavy Weather Sailing, published by Adlard Coles Nautical, discusses the use of drag devices in heavy weather including sea anchors and various drogues. Chapter 12 discusses multihull tactics.
Read about the Jordan Series Drogue on www.jordanseriesdrogue.com. Note particularly the detailed US Coast Guard report.
www.seriesdrogue.co.uk gives excellent advice on configuration.
There are some videos on YouTube from ericsailrite, called ‘Jordan Series Drogue Kit for Boaters’ which show how to assemble the drogue. Also a number showing deployment of a drogue.