8:45 AM Mon 26 Oct 2009 GMT
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'Australia II wins America's Cup - 26th September 1983'
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America's Cup author and historian, Steve Tsuchiya provided two interviews with John Longley and John Bertrand on the issue of Australia II's design and specifically her keel.
First his excerpted transcript of the interview with John Longley at the Esplanade Hotel. Fremantle, Western Australia, Australia. January 9, 2007
Longley spoke of what Ben Lexcen told him about the conception of Australia II's Keel
START:
Benny says one night he is sitting [at the NSMB tank] and the only person around is a technician that's looking at the computer that's running the thing. Here's a bloke who knows bottlely (?) squat about sailing and Benny is a very gregarious guy and was talking and talking.
Finally, the bloke said to Benny, 'What's the problem?'
And Benny went through all of this (Longley points to the sketches of keel designs he drew on my notepad).
And the guy said, 'Put the keel the other way up.'
And Benny said, 'You can't do that!'
The guy said 'You can put foils on it.'
And Benny said, 'I've thought all of that and it doesn't work. I've tried it on Eighteen foot skiffs, I've tried it on rudders, everytime I tried it, it doesn't work because the drag that you get from the wing is more than the benefit of preserving the tip vortex.'
Benny's right into it. He told this to someone who knows nothing about anything. And this bloke said that the blokes up the road (NLR) can sort that.they're doing all sort of this stuff.
END
Excerpted transcript of Steve Tsuchiya's interview with John Bertrand regarding what Ben Lexcen told him about the conception of Australia II's Keel. Bertrand was interviewed at his residence in South Yarra, Victoria, Australia. January 18, 2007.
START
[Ben Lexcen] was working on the rake of the leading edge of the conventional keel. He was working on it, I'm guessing, six months, the so-called sweep back angle of the keel, a steep angle or vertical or whatever; they did lots and lots of tank testing, getting minute. changes in performance, and it's just driving him nuts.
And then he started to talk to some aerodynamic engineers.over lunch in the cafeteria .and basically, they said, 'what are you working on?'
'Keels.'
'So what is a keel for?,' because they didn't understand sailboats.
He said there are two reasons why: one reason is for stability.and, secondly, we need a keel to give lift, so the boat won't slip sideways.
He presumably sketched what he was working on and they asked him, 'Why do you have a delta wing for a keel?'
He said, 'Well, because if you have a square keel you'll have massive tip losses.' Tip vortex, they call it.
And they suggested, 'Why don't you put wings on it, have you heard of 'winglets'?' And he said, 'no.'
They were developing winglets at the time, secret work at the time.
That was the essence of it.that's what Benny told me.
So that was started on the back of an envelope and Benny went away with van Oossanen and others, Joop Slooff and these other characters, and the winged keel was developed.
END
The above stories are, in essence, consistent with a passage from Bruce Stannard's book, Ben Lexcen: The Man, The Keel, and the Cup, published in 1984.
Stannard writes: 'Ben had tried the winged keel idea before and he was unsure whether it would work.' (pg. 72)
He quotes Lexcen: 'I had convinced myself that the penalties I would pay in extra wetted surface would be too high. But when we were in Hollandwith Peter [van Oossanen] we talked about all sorts of weird ideas and it came up and just grew from there.' (page 72)
Tsuchiya points out that he is not trying to discredit Lexcen, adding 'I believe Lexcen was the lead designer of Australia II because he put the whole package together, but the evidence, including his own testimony, points to having partners who made significant contributions to the design of the yacht.'
by Steve Tsuchiya
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Hamilton Island, QLD
