Rolex Sydney Hobart - Of Daggerboards, Drilling and Drops

by Crosbie Lorimer on 29 Dec 2015 Not so many years ago, the stories of storm damage on yachts at the front of the Rolex Sydney Hobart fleet centred on damaged canting keels. It was, after all, the early days of that quantum design leap; but much has been learnt in the intervening years – not least through the ‘test bed’ program of recent Volvo Ocean Races around the world - and a failed keel ram is a rarity these days.

In the intervening years the exponential design curve of foil design has brought with it a new set of challenges that has become very evident in this year’s race to Hobart, with the three leading yachts on Line Honours (Comanche, Rambler 88 and Ragamuffin) all damaging – and in one case losing – a daggerboard.

The liftable dagger boards on these yachts are central to their upwind performance, especially in the light airs that most of the leading yachts experienced in the latter part of their race.

Both Ragamuffin 100 and Rambler 88 reported that the damage to their foils was caused by hitting a submerged object. Jimmy Spithill said he thought Comanche broke her dagger board when they dropped off a big sea, but no-one was really certain whether it was that or hitting something. Either way hitting a submerged object is simply not something that can be 'designed out' so the challenges lie more in how to manage the situation than in how to prevent it arising.

The chances of hitting a submerged object – particularly large marine life – are surprisingly high, if their reported incidence over recent years of this race is anything to go by. Gordon Maguire, helmsman aboard Ichi Ban said they hit a sunfish this time around, “People don’t realise how big they are” said Maguire, “an adult can be as wide as this boat” he added.

But for the high speed super maxis the lateral forces exerted on these foils when they drop off the back of a steep wave are also enormous. You have only to watch the spectacular footage of the new Imoca 60s to see the degree of lateral movement that that they experience when cresting a wave in semi-displacement mode to understand those forces.

And while the super maxis don’t experience quite that level of lift, the speeds they reach upwind (up to 13 knots) mean that they will readily ‘launch’ off short steep seas, slamming down into the trough with huge lateral forces.

“Carbon fibre is such an unforgiving material” said Maguire “sometimes the crashes are so heavy when you drop two to three metres off the back of a wave you just can’t believe that the boat is going to survive”. (Two broken bunks aboard Chinese Whisper attest to those forces).

It says much for the design and construction of all three super maxis that they all stayed the course, with the phrase ‘limping to the finish’ being a common expression from on-board reports.

So what options do you have to stay in the race when you damage or lose a daggerboard?

Firstly, much depends on the design and configuration of the dagger board itself. For some years now many of the round the world race yachts have incorporated symmetrical dagger boards that can, if the need arises, be end-for-ended so that they can still be deployed on the opposite tack.

That exercise is a major challenge in itself when at sea and is largely only possible for outward angled dagger boards with the boards’ hoist gear rigged to the mast and the operation preferably carried out in next to no seaway. Such is the design aboard Ragamuffin 100, which lost its port dagger board during the gale that hit the fleet during the first twenty-four hours.

And ‘lost’ it really was. “It’s gone completely” said David Witt, skipper on Ragamuffin 100, when he spoke to the media office as they sailed down the Tasmanian coats yesterday, “we are no longer the owners of that dagger board!”

Fortunately – from a repair perspective - Ragamuffin 100 was languishing in one of the ‘holes’ that were forecast for this phase of the race when they started the ‘swap’. The game comprised lifting the starboard dagger board completely out of its casing, drilling out a new lifting ‘hole’ at the bottom end of the board and end-for-ending the board each time they tacked! Not something to relish in anything but the calmest of seas.

“Yes, the first tack was interesting in 30 knots and a seaway” said Campbell Knox, crew member aboard Ragamuffin, today. That first tack took nearly thirty minutes, but once the guys got into the rhythm we had that down to about 6 minutes in the Derwent River when we were having a tacking duel with Rambler.”

“Getting the board out and drilling a new hoist point is not that complex” says Tim Bennett, one of Comanche’s builders, who is here in Hobart and preparing to replace the starboard dagger board that Comanche lost in that same gale. “The biggest challenge in all of that is getting the dagger board back in the new casing, when the boat is moving around’, adds Bennett.

Campbell Knox said that from their perspective on Ragmuffin, the hardest part was ensuring that they didn’t damage the mast or spreaders.

“The dagger board hoist is fixed just below the first spreader and at full hoist that only gets the board flush with the hull. So we had to rig one of the fractional headsail halyards to the board to hoist it fully out of the casing” said Knox looking up at the spreader and adding “I’m not sure the radar survived all of that in tact!”

Comanche’s dagger boards are inward-angled – as too are Rambler’s - with a hoisting ‘rig’ separated from the mast. Furthermore the structure of the dagger boards is not symmetrical, with the stronger structure closer to the hull. So reversing those boards was simply not an option for the Comanche team.

Instead skipper Ken Read had to work out how best to sail on starboard tack, with no port dagger board.

'We've learned how to sail the boat a little differently without a dagger board and with only part of a rudder,' said Comanche skipper Ken Read yesterday, adding 'fortunately we've got an incredible crew on board this boat that figured out a couple of little tricks ……and off we go.'

Read’s and Kirsty Clark’s recall of the moment the dagger board broke gave some indication of the seriousness of the event. The broken bottom half of the foil was still attached to the upper half and was threatening to puncture a hole in the hull.

The damage done to Comanche’s rudder, apart from the taking the tip off the foil was mostly confined to the tiller arm. “The rudder was quite literally facing backwards when we started to gauge what had happened” said skipper Ken Read “the arm is still being held together by three threads” he added on arrival in Hobart.

The rudder damage is obviously repairable here in Hobart “they didn’t ask the boss to bring down the spare rudder from Sydney with the replacement foil!” said Bennett, whose job will be to get the boat repaired in time to sail her to Melbourne prior to her shipping to Charlestown in early February.

Ken Read attributed the efforts of Casey Smith (who has sailed two Volvo Ocean Races with Read and who played a key role in the build of the boat), Tony Mutter and others as being instrumental in the decision not to retire,

“When you see the boys getting the tools out you know there’s still a chance.” he said, adding “Casey is one of the most under-rated ocean racing yachtsman, he is a sailing star. These days I wouldn’t even leave the dock in a dinghy without Casey Smith.”

The damage from a hit to a dagger board isn’t always confined to the foil itself. “Often the major damage to the dagger board is done to the bearings in the casing” said Steve Quigley, naval architect on the Wild Oats XI team, in Hobart today. “They can get compressed with high impact lateral forces. You can often still use the dagger board but you might have much less movement in it”.

“The key to sailing without a dagger board is how you use the keel” adds Quigley, “it’s not actually that difficult.”

Xavier Guilbaud, one of Comanche’s design team at VPLP Design echoes that thinking. “We found in our design evolutions for Imoca 60s that angling the keel forward a few degrees helps provide additional upwind lift which complements the dagger board’s role. We tried an angle of 5 degrees initially and then kept pushing it because it improved progressively” he said today, as he waited for Comanche’s arrival.

“Comanche has her keel angled 8 degrees forward of vertical and that’s about the limit without requiring major structural modifications (and hence more weight) to the keel box and hull”.

Over and above the technical options, what strikes you most when you hear the various crews recall how they handled these challenges is that a deep knowledge of the boat’s construction, a large degree of inventiveness and a gritty determination to win come what may, are the first essentials in making a call to keep going, when those of lesser experience would long since have been calling it a day.