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Or put it another way

Self righting or unsinkable - which is better??

One of the perennial arguments between supporters of multihulls and monohulls is "Is it better to float upside down or sink?"

Notice I used the phrase "self-righting", not "capsize" for ALL boats can capsize. It is only recently that one specific type can self right after a capsize (providing it doesn't flood and sink first). Yes I'm talking about monohull keel boats with external ballast. Many will be surprised to learn that they are the newest of all sailing vessels, for 150 years ago they didn't exist. Multihulls on other hand sailed for thousands of years in the Pacific and Asia, while all European voyages of discovery and trade from the Phoenicians onwards have been in non self righting boats.

However history isn't relevant to those who say it is better to sink than stay upside down.

I know I won't be able to change people's opinions in this short article, but what I hope to do is to encourage people not to just make glib statements but rather to decide what the real chances of either sinking or capsizing are.

Let's be specific.

A monohull will sink if holed or if flooded by a large wave. What are the chances of that, and what can the crew do to prevent it happening?

A multihull can capsize if blown over by the wind or if overcome by a large breaking wave. What are the chances of that, and what can the crew do about it?

Despite the advent of GPS there are still many collisions with rocks or shore as boats cut corners as they blindly follow their chart plotter.

Running aground on a monohull is considered a stranding often leading to ship wreck. Whereas multihull sailors will deliberately dry out on a beach - to escape bad weather or even just for fun, say for a BBQ. If the worst happens you are more likely to survive running ashore in a gale on a shallow drafted multihull than a deep keeled monohull.

Whales have sunk many monohulls, but they aren't the only floating objects out there. People are a bit coy about reporting facts, so the estimates vary widely, but between 2000 and 10,000 shipping containers are lost each year. Whatever the true number, it is certainly in the thousands. Not all sink immediately, some have been know to float for over a year (those filled with polystyrene/Styrofoam float longest).

Of course, you don't need a container to hole your boat; even a log can do that. I write this in British Columbia where every year even ships are damaged by "deadheads" or floating trees, while I once saw a fridge floating off the coast of the UK. Race boats are constantly reporting being damaged by floating objects. In a recent Cape to Rio race a monohull hit a container when 1000 miles from land. It's crew were rescued just before the boat sunk by a CATAMARAN which took them to Namibia.

And what can the crew do to avoid such a collision?? Well, to be safe they shouldn't sail at night, nor sail fast, and obviously there should be someone on the bow on watch at all times. In other words, however careful or prudent a monohull sailor is, he is ALWAYS at risk of a sinking EVERYTIME he goes to sea.

And what about the large wave problem? Few people actually cruise flush decked boats with no cockpit or hatches, even though they know such boats are safer (I'm thinking of boats like Jester and early Colin Archers). Why? Because they are so impractical as live aboard floating homes. So most monohulls, especially when sailing to windward, and thus well heeled, have large openings very close to the water. And chances are that someone will open a hatch at just the wrong moment, so in fact it doesn't need that large a wave to get water below. Obviously if it is easy to get a little water below it is also possible to get so much below that the boat is swamped.

A multihull can capsize if blown over by the wind. What are the chances of that, and what can the crew do about it?

Weather forecasts are now pretty reliable, and getting better all the time. So 90% of sailors know what the weather will be for their sail. And 90% of the others never get in really bad weather. So the chances of getting "caught out in a blow" are now pretty small for the majority of sailors.

And even if you are, there is plenty a seamanlike crew can do. Reef for a start. Throughout the history of multihull capsizes it seems the vast majority are either pushing too hard when racing or are monohull sailors not used to sailing multihulls. In other words most multihull capsizes are the crews fault, not the boats.

And of course the vast majority of multihulls don't ever capsize because most crews are sensible and reef early.

A multihull can capsize if overcome by a large breaking wave. What are the chances of that, and what can the crew do about it?

The wider the boat the safer it is in waves. In fact you are just about uncapsizable until the wave height exceeds the beam of the boat. That is a proven, undisputed fact of basic naval architecture. Lie ahull in a catamaran and you'll just bob up and down. Do that in a monohull and you're likely to "roll your guts out".

It is extremely rare for a cruising catamaran to capsize in waves with no sails set (trimarans are a different matter) because despite what the media say, waves over 20ft high (the average beam of most ocean going multihulls these days) only occur in F10 conditions or more. Even then you are only "at risk" of capsizing. It doesn't mean you actually will. I know, for "I've been there done that". Not many people can truthfully say, as I can, "then the wind moderated to a F10". Even in horrific conditions (in a 32ft catamaran) the saloon carpets stayed dry. I once crossed the Bay of Biscay to windward in a gale in a 37ft catamaran. We kept the spare toilet paper in the bilges - it stayed dry.

And before anyone asks, yes I have had my fair share of being close to sinking on monohulls. Pumping for 20 minutes every two hours when seven days sail from land isn't much fun.

Having said all that, it isn't the boat that is important, it's the crew. Few people survive a sinking, especially if well offshore, while a large number don't even survive a knockdown even if the boat does (the Fastnet 79 and Queens Birthday storm proved that). Whereas most people do survive a capsize.

And of course I also have to mention the fact that keels still keep falling off monohulls. And it's not just a problem on race boats, it also happens on production boats. Well known brands like Contessa, Sigma, Bavaria and J boats have all had failures and lives have been lost. One problem is that the keel cannot be easily inspected, so any failure is always unexpected. In comparison a multihull crossbeam, say, can be inspected daily.

Nor have I started on the fact that you are far more likely to fall overboard or be injured on a monohull than a multihull, while I suspect that most emergency call outs are as a result of damage to the (single) rudder or engine failure. Most cruising catamarans have two of both.

But discussion on that is for another time.

In fact to me the real question is "why don't monohull sailors demand unsinkable boats"? It isn't as if they weren't available, the Belgian yard Etap has made them for years, so too did Sadler in the UK.

Finally, let's put the risks of sailing any boat into perspective.

According to the official 2001 US Coastguard figures, nearly 500 people died when boating. 350 were in open motor boats, 100 in kayaks/canoes, 50 in personal watercraft. So I guess no one drowned when sailing in 2001 in the USA. In comparison 24 people were killed skiing in British Columbia in the 2008/9 winter, while over 30 people drown each year in their cars in the UK.