Pushing fast multihulls downwind in gnarly conditions can be a hazardous business. Knowing how hard you can push, and when you need to back off, mostly comes down to experience. But it’s also down to preparation, says Pete Cumming.

“We cover a lot of miles on multihulls like Gunboats and MOD 70s, but you’ve always got to respect the fact that these boats can capsize easily and with very little notice.

“I’ll never forget the Round Ireland Race we did on Phaedo. When you’re competing with other boats, that’s when the red mist can come down.

“We looked across at [MOD 70] Oman Sail and they didn’t put a reef in, so we didn’t put a reef in, and we were just carrying too much sail and got hit by a huge gust. We released the sails but the drag meant we were blowing over and the mast was just about to touch the water when the mainsail battens reversed and somehow it just popped us upright. That was the closest ‘Get out of Jail’ I’ve experienced!

“So you need to learn when to err on the side of caution.”

Skim the windward hull

Flying the windward hull high in the air might look good in photos, but for speed and safety we want to get the windward hull just skimming above the surface.

If the windward hull is riding too high, it’s one of the warning signs that you’ve got too much sail up or you’re badly trimmed. Maybe you need to reduce sail area but before that there are other things you can do to keep the boat in control, such as easing the mainsheet traveller and pulling up the daggerboards.

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Pull up the daggerboards

If you’re sailing a multihull downwind and the boat feels too loaded, pushing the bows into the back of the waves, then try pulling up the daggerboards. This is one of the most under-rated controls at your disposal. It’s much easier to vary the power by raising or lowering the boards than, say, taking a reef in or out of the mainsail or changing headsails. If the boat feels ‘trippy’ then pull the boards up some more.

The other time to pull up the boards is when you’re about to go for a big bear away, maybe around the windward mark. With boards down there’s a big risk of tripping over as the sails load up during the turn and the boat is struggling to accelerate. Pulling up the boards will make the bear away easier to execute and you’ll accelerate faster.

So boards-up can make you faster AND safer.

Photo: Paul Wyeth

Reduce sail early

I’ve learned all my offshore multihull sailing from Brian [Thompson] and one of his biggest lessons is to plan ahead and be organised very early. So if you think you’re approaching some big weather, this is when you need to reduce sail area early.

Once you hit the big conditions the boat can quickly get out of control and you’re really just a passenger. So when we see a cold front coming, we’ll get a reef in early on the mainsail, and change down a size on the headsail.

Beware the death zone

The Death Zone is the zone of power, typically between 90° to about 110° true wind direction, where it’s easy for things to get out of control quickly.

When you’re in the Death Zone the sails need to be twisted and both hulls flat to the water. Because if you have a big hull fly in this zone, no matter what you do, steering up or steering down, you’re going to have to go through an even more powerful zone. The trimmers need to be focused and ready to react because the driver doesn’t have the time or opportunity to steer out of a problem if a gust hits.

Macif Ultime trimaran in big conditions during the Brest Atlantiques. Photo: Alexis Courcoux / Brest Atlantiques

Do the ‘Mich Desj’

Sometimes you’re going to get caught out by a massive gust or squall. The first thing to remember is not to panic. When it feels like you’re running out of options to keep the boat safe, just go through your checklist. Is the daggerboard up as far as it will go? Are the sails eased enough? How much further can you let the traveller slide to leeward?

If you’ve done all that and you’re still feeling on the edge, then there is still the ‘Mich Desj’. I learned this from Brian, who learned it from Michel Desjoyeaux who worked out this manoeuvre that sounds crazy, but actually works. We’ve used it a few times in the MOD 70, when we get the daggerboard up as high as it will go, get the boat feathering almost head to wind and then pull on the jib really hard.

Slow down until you’re making between 5-10 knots towards the wind, then you smoke the mainsheet and the traveller and aggressively bear the boat away until you’re going dead downwind. The idea is to bear away at slow speed which also keeps your apparent wind low too and prevents the boat from accelerating into trouble. It’s amazing how effective it is with the jib pinned in, and once you’re borne away you’re in a better position to put another reef in the mainsail and change to a smaller headsail.

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