A Bow for a Bow: The Interview, Part I
A Bow for a Bow: The Interview, Part I
The Prada design and construction teams were busier than any of their contemporaries during the Louis Vuitton Cup. After a discouraging 4-4 record in Round Robin 1, they did the first of two major facelifts to ITA-74, the second coming after the quarterfinal loss to Alinghi. In addition they also did some major reconfiguring to the bow and stern of ITA-80, they syndicates second boat, which never sailed in the competition. The changes did help significantly, Prada went 7-1 in the second round robin and was able to survive until the semifinals, where they were eliminated by OneWord. To get a better idea of how a team goes about replacing a major chuck of an Americas Cup boat, we interviewed four key people from Pradas shore crew. The story appeared in the February issue of Sailing World. Part I of the interview is below. The second half will be posted on Jan. 20.
During this interview, conducted on Dec. 13, 2002, youll hear from the following four members of Prada:
Aeronautical Engineer Andrea Avaldi (Italy)
Composite Engineer Will Brooks (UK)
Naval Architect Claudio Maletto (Italy)
Lead Boat Builder Sean Regan (New Zealand)
For their complete biographies, please scroll to the bottom of the story
SW: Can you give us a rough picture of the process involved with changing the bow, or any major part, of such a large and delicate boat?
Andrea: Before going into the detail, or a little bit of the details, of the operation, maybe Claudio Maletto can explain the strategy behind making those changes.
Claudio: When we arrived in New Zealand, we have some testing before the racing and also some preliminary racing in Round Robin 1. At that time we discovered that we had to improve our performance just to stay in the game as long as possible. So we decided to start some testing in the towing tank in Rome, the facility we generally use for this kind of test, and we decided to do some changes to the boats. All the changes are under the rule, we call it Protocol Rule 16, that allows us to change the boat 50 percent, that is a huge amount in terms of area. So we made a plan for both boats. Dont forget that at the moment we are using ITA-74, but we also modified ITA-80, the second boat we launched here in New Zealand. The modifications cover a large area, not only the bow, as we did mainly in ITA-74, but also the back of the boat as we did on ITA-80. This is only part of the plan of improvement for both boats because also the appendages were changed during this period.
Andrea: I think that Sean can explain best the pressure on the shore team.
Sean: GDay. I guess the first initial stage comes when we have some designers who walk out of their offices with big smiles on their faces, having come up with some ideas to make the boat go faster. Once it becomes more apparent, it involves a lot of work. Obviously youve got to sit down and make a plan for the works involved. I guess the biggest thing here is the time factors that were involved. Were on a very limited time to get the new component made. Its a case of sitting down to start with and getting your head around the project and what is going to be the quickest way to do it. There are standard procedures that come from general boat building that are generally used, but obviously youve got to find ways to cut corners without actually being detrimental to the construction.
The hardest part is getting the designers to confirm what they actually want. Then its a case of liasing with the composite engineers to decide how big the piece might be, where were going to join it, and how were actually going to go about making it up. After that its a case of going through the boat building processes.
SW: The bow is built separate of the new boat. Whats the first step, is it breaking out chainsaws and cutting off the old part or is it more delicate than that?
Sean: It needs to be almost as aggressive as that. People would like to see a chainsaw. When the boat comes out of the water, that first night, is critical because were on such a short time scale. While the boats on the tow, back from the racecourse, theres a big team assembled in the shed, ready to go. Everybody has their job and it starts as the boats being hauled out of the water, the riggers are in there dismantling the rig. Once the boats on the hard, the rigll come out, the boatll then go straight in the shed, come off its keel, and then be flipped over and set up level. Once thats established, we can then go about marking the cut line and doing the cut itself. For the cut itself, the biggest part is setting up, making sure youve got your marks set up which relate to the new component youve made. As long as youve got that side of things right the job tends to run smoothly. One thing I should note, prior to the construction of the new component, its actually very important that you match the join areas with the existing boat. This actually involves getting out at night [while the racing is still going on] and templating the boat in the areas where youre going to blend the new piece into the old piece.
SW: This is a super precise operation. Are you using lasers and other very accurate instruments to make the measurements?
Sean: We use as much of the modern technology as we can. Im a traditionalist at heart, personally, and I like to do things the old way. A lot of my set up involves string lines and plumb bobs. Theres nothing more accurate than basic tools.
|©Courtesy Team Prada/Carlo Borlenghi|
|A quick fix inbetween the first and second round robins (above, after being removed) helped push Prada close to the top boats. A completely new bow (below) was added after the quarterfinals.
SW: The part being replaced, is it cut with a jagged edge to help the join or is it a straight edge? Whats the technology involved with meshing that the two pieces and making sure that joints strong enough?
Sean: Ill hand you over to Will because its the actual materials that we use to do the bond that are the critical thing there.
Will: What we try to do when we do a joint is to keep everything as simple as possible, especially when theres a tight time frame. Although doing a jaggedy joint would be quite nice, we tend to keep the cuts very straight, very plain. Then we come up with splicing details to splice the skins and the core together for each part. In fact, fitting a new bow on, structurally speaking, is quite a simple operation. Its all the other bits that go with it. On ITA-80 we moved the keel structure forward and we moved the mast. On ITA-74 we also moved the mast structure. Its these things which give us a structure nightmare because theyre much more highly loaded.
Andrea: Something about these structural modifications. Will was mentioning the modifications to ITA-80, which were much more than what we did with ITA-74, because it involved the keel structure inside, the mast structure, and basically all the bulkheads in the front as well. Also we did a modification to the stern which was a different type of modification because we needed to stay inside the 50-percent modification of the entire hull. Basically, what we did was cutting the stern like you can do with a banana and trying to change the shape of the hull in a way that let us achieve the desired shape without having to cut or remove too much of the original hull. Of course by doing that we had to go through several bulkheads, so the tailoring process and the bonding back was quite long as well. This process ended up in having Will and myself, basically the morning before going out racing, testing the boat at the dock and then testing the boat a few hours before the declaration of the boat itself. There was a lot of pressure on the shore team, but there was a lot of pressure on us as well.
SW: When you design or build these boats do you make any concessions for redesigning the boat, beefing up certain areas, placing bulkheads in certain areas?
Andrea: ITA-74 was not designed to accept any modifications so we, Will and myself, tried to maximize the stiffness of the boat and to minimize the weight [during the initial construction]. This gave us a hard time trying to change stuff inside. ITA-80, instead, was a slightly different boat structurally speaking. Not that it was easy to modify, but much easier than ITA-74. What Will and myself have learned from this campaign, is that theres a lot of [potential value] in trying to design something that is then easier to be modified.
Andrea Avaldi (Italy) - Aeronautical engineer. Andrea was born in Milan, Italy, in 1964. This is his second Americas Cup experience; both have been with the Prada team. He, along with Will Brooks, is responsible for the structural design of the yachts. In 1991 Andrea graduated from the Polytechnic in Milan with a degree in aeronautical engineering—specializing in structures. He then moved to Turin, where he worked at the Fiat Research Center, specializing in structural analysis by finite element methods. In 1994 he returned to Milan and worked for various aeronautical firms. In 1995 he began consulting in computation and structural design for F1 teams, including Ferrari. He is married to Maria and has two children, Pietro and Paolo.
Will Brooks (UK) - Composite Engineer. Will is in his second Americas Cup with the Prada team. He was born in 1967 in Plymouth, England. After earning a degree in mechanical engineering at the Heriot Watt University in Scotland, he earned a masters degree in naval design from the University of Southampton in England. He has several years of experience as a consultant in the maritime industry. For four years he worked for SP Technologies in England, where he was in charge of the structural design of several cruising and racing yachts, including the avant-garde Tiketitan and a new Wally 105-foot yacht with canting keel. He is married to Amanda and has a daughter, Rose.
Claudio Maletto (Italy) - Naval Architect. Born in 1948 in Varese, Italy, Claudio is also in his second tour of duty with the Prada team. However, this is his third Americas Cup, having worked from 1989 to 1992 with the design team for the Il Moro di Venezia challenge. After earning his degree in architecture in 1972 at the Polytechnic of Milan, he began designing racing hulls with Flaviano Navone at the offices of Franco Fontana in Como. FMN earned its first important international result in 1978 when one of its designs won the world Mini Tonner championship. This was followed by many national and international titles in the five IOR Level Classes. After the 1992 Americas Cup, Claudio focused primarily on IMS racing boats. His designs recorded victories in the 1995 and 1996 national championships and in the Commodores Cup and Sardinia Cup of 1998. A passionate sailor, he has been active in international racing in the 470 and Laser as well as the IOR and IMS classes.
Sean Regan (New Zealand) - Head Boat Builder. Born in Christchurch, New Zealand, in 1967, Sean is in his fourth Americas Cup. In addition to Prada, he has worked, as a boat builder, for New Zealand in 1992, Chris Dicksons Tag Heuer challenge in 1995, and John Kolius Abracadabra effort in 2000. He was also involved the construction of Steve Fossetts PlayStation.
The rest of the Prada design team includes: Alessandro Benigni, Sail Design and Development; Steve Calder, Sail Design and Development; Mattia Carpini, Design and Drafting; Guido Cavalazzi, Sail Design and Development; Miguel Costa, Deck and Systems Design and Development; Michele DellAcqua, Mast Design and General Construction Design; Luca Donna, Structural Design; David Egan, Technology Director; Scott Ferguson, Mast Design; Jan Howlett, R&D and Design; Michel Kermarec, VPP Development Coordination; Juan Kouyoumdjian, Naval Architecture; Jed Lowry, CFD Development; Juan Meseguer Torregrosa, Sail Design and Development; Paolo Periotto, Deck and Construction Design; Giorgio Provinciali, VPP Development; Bruce Sutphen, Measurement Instruments Development.
For more on Prada, www.pradalunarossa.com