Tuesday, September 3, 2013

WRITING THE RULE


Gino Morrelli and business partner Pete Melvin have been successfully designing state-of-the-art multihulls for a very long time, but other than their involvement in the 27th edition of the America’s Cup, which saw the Stars and Stripes catamaran win its defense against the Kiwis, they’ve been absent until recently from the AC scene for obvious reasons. They were seconded by Oracle for their (successful) 2010 challenge against Alinghi, and this go around, the M&M team participated in writing the new AC72 Class Rule before being hired away by ETNZ to design its AC72. Pete joined the team in New Zealand, while Gino has been holding the fort in their Newport Beach, Calif., office and been peripherally involved with design team meetings.
Morrelli’s hot on foiling as the way to go forward in all things AC. “Most people don’t realize we’ve been dealing with foiling for almost four years, before the 2010 Cup," he says. "We designed the Nacra 20 that’s been in production for five years now, that had curved foils; prior to that we built an A-Cat with curved foils. We’ve been building power cats for 15 years with foils. People playing with catamarans have been playing with foiling for a long time.” We caught up with Morrelli for his insight on the big picture of the AC72 design:
 The 72 seems to be a designer’s dream and a sailor’s nightmare. How did you get to the boat we have today?
GM: Most of the 72 was dictated by Russell [Coutts] and the Oracle guys. After the 2010 Oracle campaign, they retained us [morrelli & Melvin] to do some performance analysis on different sized trimarans— a trimaran being the original contender with a soft rig. We did all kinds of analysis on things from 60 to 90 feet—cost estimates, performance estimates, and providing them with a matrix of options there.
The cat was part of an early allegiance to move boats from one country to another—de-mounting boats and shipping boats on planes around the world—cats would simplify this craziness, [with] less parts. The transition to the wing on top of it—there was no real research done on our part—was just like a declaration by Oracle, “We want a wing. Tell us how big a wing we can put on.”
Then, they constrained us with needing to fly a hull in 6 knots of wind. Once the boat size was determined, it determined the wing size by the requirement that it had to fly a hull in 6 knots of wind—that opened up the whole Pandora’s box of the rig being really big for San Francisco. That’s where the idea of two rigs came about—big and little—with the rig committee determining the night before the race which rig people would have to use. That got dismissed because of cost and management problems. The next idea was to put a removable top on the rig—15 feet off the rig—but the harsh reality of taking tops of rigs with control systems, etc.? Not really. So we ended up with the big rig for all purposes all the time. Due to cost and complexity, the idea of an alternate smaller rig also went by the wayside. I think it was one of those situations where Oracle ran out of time, and it was either do nothing or mandate a whole lot of expense. Everybody knew you’d end up with a boatbuilding team and a wing-building team. The two never really cross over very much—you end up having to babysit the platform with a set of guys and same thing with a wing—it now takes 35 guys to launch a wing.
 Let’s assume multihulls carry on into AC35. What will follow the AC72?
GM: I think the excitement that has been generated in this Cup has way more to do with foiling and flying than the wing. If we used the same platform with soft rigs and rotating masts with fully battened sails, then first you can reef them, second you can launch them at your leisure like a normal boat, and third you eliminate the wing-building team and the problem with the handling of the wing, the hydraulics, and control systems. In reality the difference between the performance of the boats with a wing on foils and without the wing on foils, won't be much. They’ll still sail at 40-plus knots. Maybe they don’t sail at 165 degrees downwind, but at 163 to 160, and they’ll probably still fly in as little wind.
When we did the ’88 campaign with the soft rig and the hard rig, the delta between the two boats in the end was only about 1 or 2 percent, which is huge if you’re racing those boats against each other. There is a lot of economic push to go back to monohulls because there are guys sitting on the sideline that got pushed out in 2010. In fact, when we were developing the Rule for AC34, we’d get calls like, “Well, how many guys are going to be on board?” or, “You’re not going to put that engine on board are you, because that’ll displace about eight guys.” Some of these guys had made their livelihood off the Cup for 30 years.
Should the boats continue to foil if multihulls remain?
GM: I think it’d be a travesty if they didn’t foil. All they have to let us do is articulate the rudders, put flaps on, or articulate the rudders and angle the tack, and these boats will get way faster overnight. The benefit that we’re tapping into right now is just beginning. Back in ’88 I was involved in researching the defense of the use of catamarans in one of the court battles. One of the things we learned was that George Schulyer who wrote the Deed of Gift, sailed a catamaran. The naissance of the America’s Cup has much more to do with the American defense program. The Cup was taken from England when we were just a baby of a country compared to England. The reason that the AC victory was so fundamental at the time was that it was a breaking out of American ingenuity and technology, challenging the English. The DofG was an attempt to create an event that promoted naval architecture for American defense as it was for a yachting competition, at a time when domination of the sea controlled your security for trade and prosperity—all those guys were nation-builders back then. It was the space race of the time. That’s what the Cup is.
 What’s your opinion on the subtleties of the hull shapes?
GM: They almost don’t matter anymore. Even upwind, unless you’re sailing in 2 knots of wind, you’re always trying to generate a bigger fraction of lift off the daggerboards. When we first started with ETNZ, the only tools we really had that were highly developed were all based on monohulls. It took about 3 or 4 months before the CFD tools got sophisticated enough to start accounting for daggerboard lift because it’s a very interesting mathematical problem to analyze a hull that goes from fully immersed in displacement mode to flying in the air. The whole drag curve tradeoff with the size of the foils, the position of the foils, angle of the cant—all that had to be developed. A big matrix of hull shapes was generated, and we looked at every boat that was relevant in the last 3 or 4 years, whether it was an A Cat, a F18 or F20, anything in that genre, and ran it through the CFD. In the end, from the best to the worst it was like .5 percent. There wasn’t any giant delta to be won or lost. After going through 50 to 60 boats, the fastest hull shape was basically an existing boat. The joke was, “Don’t let Grant know because he’ll fire us as we’ve just spent four months trying to find a better hull shape and we couldn’t.” The whole idea of hull shapes being important has been superceded by how important daggerboards are and foils are. We joked that the hulls had become “board delivery devices."
 It was suggested that ETNZ’s hull shape probably saved them from a worse fate in their recent nosedive?
GM: With ETNZ’s recent crash, the hull shape did come into play, but it was the volume that was important, not the shape. The only important decision with the hull shape design was how much bow you stuck in front of that daggerboard to accommodate for any crash, and that’s where you see a delta between the shapes, between Oracle, Artemis, and ETNZ—how big a bow to stick on it to survive the inevitable which is what happened to Oracle when they capsized. Both teams did a weather hull pitchpole. We’re not capsizing over the leeward hull, we’re starting to capsize over the weather hull, which is a completely new way to capsize a catamaran. The hull shapes are not going to determine who won or lost the America’s Cup by a long way except for the lack of survivability—the nose—Oracle’s a lot finer, a lot narrower in the front, and we’re a little fuller and taller. We carry around the extra windage and a little more weight.
 You and Pete were part of the team who wrote the Class Rule then went on to design ETNZ’s boat. What was the benefit to ETNZ?
GM: Obviously we had an insight as to why it was written the way it was. We were directed by Oracle and Mascalzone Latino to address any particular fundamental issues, like hull point speeds, weight, crew limits, that sort of thing. It was very much a big group working together for months. Like any group decision it’s never perfect. It’s a bunch of visions pushed together with certain compromises. We [Melvin & Morrelli] took a bit of a different path—we had about six of us in our office who were involved in the Rule writing, so we divided the office in half, with half the team writing the Rule and the other half troubleshooting the Rule. For example, Pete was writing the Rule, and I was on the other side challenging the Rule.
One of the jokes in-house was that we were very wary that we could write a rule and have a loophole in it that we would not be aware of, and once it got published we were particularly concerned that someone like Juan K. would read the Rule and interpret it to the point where he’d find a loophole and someone would somehow magically come out with a Rule-beating boat that somehow we had never envisioned. So we were always saying to ourselves, “How would Juan K. read this?” In the office we would force internal argument about the definition of every single line because we were trying to define something that didn’t exist, that was new.

Wasn’t the Rule designed to discourage foiling?
GM: No, that’s a bunch of crap. When we were writing the Rule we were really pushing Oracle and Mascalzone Latino to take all the constraints off the daggerboards and rudders and let it be the Pandora’s Box: Let’s have active control systems and wands, let’s see what people can come up with. Oracle was quite supportive of that, and we wrote a Rule. One edit that survived 2 or 3 weeks stated that there were really no constraints on daggerboards and rudders—you could have articulation, flaps, moveable systems, you could have moveable extensions like a Moth or a tri-foiler.
The ML guys weighed in and put the veto on it—they didn’t want to let these boats out loose with no Rule. I think the rationale at the time for them was that they knew Oracle was already going to have a headstart on the wing, and they knew that we already had curved foils on the trimaran. They knew that the big boats were already progressing toward higher lift fraction (the amount of lift that the boards produce as opposed to the amount of lift the hulls produce, like a fully-flying boat is a 100-percent lift fraction—all the higher boat weight is on the foils whereas you could have 90-percent lift fraction, where 90 percent is on the foils and 10 percent on the hulls). At the time Oracle was fully supportive of a full flying boat, all bells and whistles. But we were asked to back it down so we reluctantly started trying to carve out a Rule that didn’t preclude flying but made it a little bit more challenging without all the bells and whistles.
 What were the compromises which have resulted in somewhat “awkward” daggerboards?
GM: The compromise was to allow the daggerboards a fair amount of freedom—you could cant them, change the rake, twist them, rake them up and down, but you couldn’t translate them, which means move them fore and aft of the boat which is important for certain windspeed conditions where you may have a big gennaker up front and may want to move a board forward, for example, but that would have been a big structural challenge. It was agreed that we could put elevators on the rudders—we still wanted to have articulating elevators so that the elevators could move like an airplane with flaps that the crews could actively adjust like a Moth. So, the outcome was we got elevators but no controls.
The joke was it was like giving us an airplane that could fly but with a dead stick. You don’t get to change its angle of tack or control with the rudder. It put all the emphasis on changing the flying on the daggerboards. At the time I think they felt that was going to be a big enough constraint to keep the boat costs down by not having all these crazy systems—wands, sensors, crazy hydraulic pressures—and that would make it hard to fly. Oracle and Artemis made early assumptions that you may not get there from here, but we knew we could fly—we’d had experience with three or four other cats.
 Where do you think your experience really kicked in for ETNZ?
GM: The 72 was designed from the start as a foiling boat. We’d already designed the SL33 with curved foils. ETNZ immediately bought two of them, and we tried dozens and dozens of foil combinations on the SL33 before we built the first 72. By allowing us to have elevators, everyone knew that we were going to fly. It was just a matter of how we would control it, and that’s where every team has fought for a various technique to control flying in a response to the rule restriction. If we could control the rudders we would have a different daggerboard. We knew we would fly but not whether we’d fly under control. We were afraid that Juan K. or Dirk Kramers or one of the other smart guys around the table would figure it out before we did. As it turns out, we have a solution that gets us around the racecourse.
Pete [Melvin] has said previously that multihulls can be match-raced, a sentiment not shared by many. Do you concur?
GM: I don’t care. The America’s Cup is not about match racing. The America’s Cup is about building the fastest boat possible to get around the course. Match racing was really only an evolution of the 12-Metre and boats that go slow. You have to read the Deed of Gift to understand the intention of the America’s Cup.
Can you point out the design differences with Luna Rossa’s first generation 72 versus ETNZ’s Aotearoa?
GM: Yeah, they had a generation 1 boat, and we had a generation 2.5 boat. There was a lot of refinement in the systems that control the boatspeed and maneuverability. You have to have fully-orchestrated maneuvers now to keep the thing on foils and coming out of the jibes with the minimum loss of VMG. The difference between a good foiling jibe and someone basically dropping a hull in the water is around 400 meters. Now the difference between a good foiling jibe and a bad foiling jibe is still 100 meters. A lot of it is maneuverability, the articulation system of the wing, the self-jibing of the jib, the crew-weight transfer, daggerboard timing going up and down—all at 45 knots in racing pressure, or what we call, “racing in anger." It’s where the big deltas are going to occur.

Likewise, what’s with the Oracle boat that stands out versus ETNZ’s boat?
GM: Oracle have a narrower boat so if we get into displacement sailing, like in 8 knots of wind, they may have a “slippier” hull which may be an advantage if it’s super light. Just watching them sail over the past six to seven weeks you can see that they’re climbing up the learning curve fast. Their daggerboards and control systems have evolved towards ETNZ’s. They have a theoretically better system, but I think they’ve basically thrown in the towel and said, "We can’t seem to make this work, we’re going to have to go to a self-adjusting system, a self-leveling system." So they gave away, I think, one of their potential advantages in a breeze.
Oracle’s biggest advantage is more time in San Francisco, more money and resources. They probably have the ability to sail the boat “in anger” than ETNZ may choose to at certain points. Kostecki has probably got 10,000 more hours on the Bay than Ray Davies or Dean Barker, like one event last summer in the ACWS where Spithill went from dead last to first in one blast, literally sailing through the fleet. That’s a clear advantage. I think Jimmy is aggressive enough that he could drive the boat toward major league danger and force Dean and ETNZ to flinch. They have the resources to be able to risk it all unlike ETNZ. Oracle may be willing to risk and pull the trigger to kill the program in a jibe.
How do you control costs in this game?
GM: If you mandated all the boats to go back to soft rigs and change the box so that wings were eliminated, you’d kick out a bunch of costs. I think the whole argument about money is a fallacy—every team will spend what they raise. We could make the boat half as big and Larry Ellison would spend just as much money. The team doesn’t get any smaller! We’re not controlling costs by controlling boats or people. Even Dean and Grant [ETNZ] would spend every dime that they raise if they could.
 Is there already some back-room designing going on somewhere?
GM: Absolutely.

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