Rod Davis
A lot going for it
For the past six years the Sled TP52 team, owned, steered and led by Mr Okura, have raced their TP52 of the same name… Then in June Mr Okura decided it would be great
fun to try sailing 12 Metres in Newport, Rhode Island. Where else? Newport is the true home of 12 Metres and the America’s Cup, where the
history of so many Cups, the New York Yacht Club, and the successes and failures of challengers and defenders alike lie embedded in the cobblestones of Newport’s streets. Only one little problem, neither Mr Okura nor much of his team had
ever stepped foot on a 12 Metre, let alone hoisted a sail or raced one. Thus a crash course in 12 Metre sailing was going to be a prerequisite. Oh, one more little problem, just an hour of practice time before the first race! In the coaching world we refer to these as ‘challenges’; the word ‘problem’ has too many bad vibes associated with it. It would be hard to conceive of a bigger difference between boats
than a TP52 and a big, heavy, slow boat like a 12 Metre. Yacht racing in the past 30 years has charged away from this style of boat, towards quick, nimble, planing dinghy-style boats… TP52s, RC44s and J/80s. To get the Sled team’s mind in the right place I wrote a couple of
papers on sailing a 12 Metre. Why me? Most experience, I guess. In the last four America’s Cups where the ‘lead belly money gobbler’ (12 pounder, or 12 Metre) was used I was bowman, coach, main trimmer and skipper. And rather than point out the raw differences, I wanted to explain it in a way that would stick in the team’s mind as they learned the ropes the way they used to be, back in the day, before planing keelboats became the norm.
Part I – VMG SAILING 4-16kt of wind A 12 Metre is very heavy so it takes a long time to build speed. And because it is heavy the inertia carries the speed for a long time.
30 SEAHORSE Think of a 12 Metre as a big battery of boat speed – you charge
it up by sailing in a power mode. Upwind that means sailing 1° or 2° lower, downwind it is 1° or 2° higher (unlike a TP52 where mainsail twist does the trick). The differences between the boat speed and the target speed tell
you how much charge you have in the battery. If you are half a knot under target speed you don’t have much charge in your battery and it is necessary to get charging again. Going over target you can use the extra charge by taking a smooth bite, to windward upwind, or to leeward downwind. A strange thing is that 12 Metres charge their ‘batteries’ faster
than they lose charge from them. So you can snake upwind, charging for part of the time, and using that extra charge at important tactical moments. The really hard part is that the boat speed (the charge indicator)
lags behind the actual charge of the 12 Metre battery. This is probably due to the boat being so heavy and having so much inertia. But another factor is the averaging in the boat speed you see (to keep the speed read-out from jumping around) means the display is six to eight seconds behind the actual speed of the boat. Of course the instruments are from the 1987 America’s Cup. Ockam; state of the art 30+ years ago! Upwind in the TP52 you build speed by easing the main and steering
straight; in the 12 you turn the boat down just 1° or 2° and wait. Both sails get eased just slightly. The TP52 takes about six seconds to gain 0.3kt of boat speed; the 12 will take 20 seconds. But… when you do see that boat speed going up, the charge of
the battery increasing, you go back upwind before you are at full charge (target boat speed) because of that inertia and the instrument lag. If you don’t you will over-shoot the target speed by too much. It’s like you have to anticipate where the boat speed is going next
before the speedo tells you. Your hints are how long you have been charging or draining your boat speed battery, how severe or aggressive you have been, direction and how fast the boat speed read-out is moving.
MAX RANCHI
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