The Unflinching Designer: Paul Bieker

A conversation with Paul Bieker, Oracle Team USA’s principal design engineer for the 35th America’s Cup, about the design work that goes into making an ACC yacht capable of such staggering, foil-borne speeds.

America's Cup
Oracle Team USA practicing for the 35th America's Cup.Sam Greenfield

OTUSA won eight straight races and achieved the greatest comeback in sports history.

September 2013: Oracle Team USA was down 8-1 in a best-of-18 regatta against Emirates Team New Zealand that would determine the fate of the 34th America's Cup. OTUSA's 72-foot, wingsail-powered, hydrofoil-borne catamaran was simply the slower horse.

Given the sudden-death predicament, Paul Bieker, the team’s design expert on hydrofoils and carbon-fiber structures, proposed several small but critical changes, including the addition of interceptors (fixed, trim-tab-like ramps fitted onto the catamaran’s stern sections) and spearlike rudder fairings that reduced cavitation-induced drag. These tweaks necessitated several all-night work sessions, but — coupled with crew changes, wing-trim changes, and modifications to onboard procedures and techniques — they unlocked the boat’s performance. ­OTUSA won eight straight races and achieved the greatest comeback in sports history.

As a result, Bieker was asked to be OTUSA’s principal ­design engineer for the 35th America’s Cup. Unlike previous Cups, AC35 will be contested aboard 50-foot catamarans that are virtually identical, save for the two most critical areas: the wingsail controls and the shapes and controls of the boats’ foils (read: daggerboards-cum-hydrofoils).

Bieker hopes to win again, and he’s excited about the performance potential of the new 50-footers.

Q:

Given AC35’s largely one-design nature, where are ­designers concentrating their efforts?

A:

They are One Design boats for the platforms and the outside shape of the wing, but the wing’s internal structure and control systems are totally open. The foil shapes and the foil-control systems are also totally open. You only get to build two sets of daggerfoils … so you’ve got to get them right.

All those things have a major effect on performance, and each one is pretty complex. The way I see it is that even with as many of the parts of the boat being prescribed by the rule, it’s still a more difficult design project than a traditional America’s Cup yacht.

America's Cup, Paul Bieker
Few designers are as experienced at foil design as Paul Bieker. His overall America’s Cup expertise dates to 2003, when he became involved with oTUSA.Courtesy Paul Bieker

Q:

Are the new-generation foils more efficient?

A:

Bigger things tend to have lower friction drag proportional to the loads, but the foils are way more efficient than in the last Cup. Structurally, they are way more challenging … [and] I thought the last ones were pretty challenging!

Q:

What’s faster, the new 50s or the old 72-footers?

A:

I haven’t run the numbers, but I would guess one of these [ACC boats] would give a 72 a pretty good run for its money around the course … and in some conditions would be faster.

Q:

At the last Cup, your team innovated some impressive last-minute changes. Could this happen again in AC35?

A:

In San Francisco, we had a lot of races with some key lay days early on in the match, so we had a pretty reasonable amount of time to get our act together and make a comeback, but we don’t have as much time in this go-around. That said, we get a chance to sail against the other competitors in the first stages of the Louis ­Vuitton Cup, so we do have some time to react and get better.

But it’s tough when you can only build two sets of daggerfoils. That’s one of the key aspects to the boat’s perform­ance, and that dice gets cast.

You always go into America’s Cup [regattas] thinking that you know what might be the key design element. But in reality, it’s most likely going to be something else that will be the key factor that’s going to make the ­strongest team ­faster. We’ve just got to be ready to do our best. Some of the teams seem pretty strong.

America's Cup
Foil-borne catamarans have evolved significantly since the 72-footers used to defend the 34th America’s Cup.Courtesy Paul Bieker

Q:

Will teams be better prepared this time?

A:

Yes, for sure. That’s the beauty of making the platform one-design and spelling out where you’re going to put the foils, where you’re going to put the wing, where the jib is going to sheet to, what’s the shape of the jibs, what’s the overall shape of the wing — that puts everybody in the ballpark. Then it’s down to figuring out how you’re going to control your wing, what your user interface with the wing is going to be like, what the foils are going to look like, and what control systems you’re going to have.

I’d expect that we’re going to have good racing.

Q:

What’s been the crux of your job during this America’s Cup cycle?

A:

In most of my four previous Cups, I’ve been more specialized, just hunkered down doing work on structures and construction. In this Cup, my responsibilities are a little bit broader. That makes it a little bit tougher and more complex.

I like to just hunker down sometimes and work on solving problems and working through the details of things, and I don’t get as much time to do that in this Cup.

Q:

Which role do you prefer, focusing as a specialist or looking at the bigger picture?

A:

I don’t know … I’d say this one, although my roles in previous Cups have been more fun. You wouldn’t say they were easier, but it was easier to define and ascertain how good of a job you were doing. This Cup is a little bit harder that way. It’s funny — in some ways my current job feels a little bit more artistic. I’m ­dealing with intangibles to some extent, risk management and more imagination when it comes to the big-picture thinking about what we’re trying to do. In some ways, that feels more human than just pure engineering.