Please select your home edition
Edition
Southern Spars

Benoit Marie at frontend of Mini-Transat after Yacht Research project

by David le Pelly on 28 Nov 2013
Benoit Marie - 2013 Mini Transat research project - Yacht Resrach Unit - Yacht Research Unit - University of Auckland http://www.mech.auckland.ac.nz/uoa/home/about/ourresearch/researchareas/yachtresearchunit/

Benoit Marie, currently lying a close second in the Mini Transat, studied for six months at the Yacht Research Unit at the University of Auckland.

Whilst at the Yacht Research Unit he built a 1/5 scale model of his Mini using flax-fibre composites which he then tested in the Twisted Flow Wind Tunnel. As well as generally optimising his sail plan, he looked in particular at the use of double-surface sails and their ability to perform more efficiently than conventional thin sails.


The prototype Mini 6.50s are at the cutting edge of design. The rule is as close to a true box rule as any come (just a few necessary stability requirements). Keels that cant and translate, rigs that cant to windward, water ballast and a huge sail area to displacement ratio, result in the most technically advanced boats around.

The next major refinement will most likely come from the sails. The power produced by a reaching sail is basically dependent on the luff length. The Mini 6.50 suffers from a relatively short gennaker luff length compared to its chord because of the mast height limit. Increasing the efficiency around the luff will make the boat go faster.

By adding a double-surface (e.g. inflatable aerofoil) to the leading edge it's possible to significantly increase the efficiency and the amount of lift produced by the section. Just as inflatable battens are now commonplace in many headsails, the technology to hold a luff pocket inflated to the desired shape is available.

The wind tunnel results showed the double-surface gennaker to be more efficient than a conventional thin sail. Certainly there's some work to do in sorting the logistics, and how to inflate the sail once it's up, but the gains could easily be huge.

Why don't we see this used more often? Because the vast majority of racing rules prohibit it.

It's from development classes such as this that technology improvements will eventually trickle down into general racing and cruising.

In the images the double-surface luff of the gennaker can be seen. The Yacht Research Unit are not aware if Benoit carried this particular research project into the actual race - with handling the double surface luff still being an issue.

At latest report Benoit Marie was just 14nm behind the race leader with 970nm to the finish. The two had a big break on the rest of the fleet and were sailing faster - so the rich look set to get richer.

The Twisted Flow Wind tunnel is one of several specialist facilities at University of Auckland's School of Engineering, Yacht Research Unit

The Faculty of Engineering also has a range of state-of-the-art facilities, including:
• A Yacht Research Unit which has been involved in the design and testing of boats competing in the America’s Cup, Volvo Ocean Race, and many other regattas since its inception in 1987.
• Twisted Flow Wind Tunnel.
• Boundary Layer Wind Tunnel.
• Centre for Advanced Composite Materials.
• Light Metals Research Centre.

Graduates of the Auckland University School of Engineering include Olympic Gold medalist Russell Coutts, Olympic Bronze Medalist John Cutler, and 2012 Olympic Gold Medalist Jo Aleh and many more top international sailors.

David le Pelly is also a member of Emirates Team NZ's design team for the 34th America's Cup specialising in Aero and Instrumentation.

For more on the Yacht Research Unit click here

Barz Optics - Kids rangeZhik Yachting 660x82Wildwind 2016 660x82

Related Articles

A Q&A with Charles Pessler, the regatta director of the legendary STIR
I corresponded with Charles Pessler, STIR’s regatta director, to learn about the event’s recent changes and evolutions. I recently corresponded via email with Charles “Chuck” Pessler, who is serving as the regatta director of the legendary STIR, to learn more about the changes and evolutions that have taken place at the event since my 2010 trip to racing paradise.
Posted on 22 Mar
New Pacific 52 class makes its debut in San Francisco
The first of two new-build Pacific 52's from Auckland's Cookson Boats is now sailing in San Francisco. The first of two new-build Pacific 52's from Auckland's Cookson Boats is now sailing in San Francisco. Invisible Hand for San Francisco's Frank Slootman replaces his earlier RP63 of the same name. She will soon be joined by a second Cookson build, Bad Pack (Tom Holthus) from the same moulds. A third, RIO 52 is for RIO 100 supermaxi owner Manouch Moshayedi.
Posted on 18 Mar
A Q&A with Chris Woolsey, regatta chair of the Miami to Havana Race
I talked with Chris Woolsey, regatta chair of the Miami to Havana Race, to learn more about this exciting race to Cuba. The 2017 Miami to Havana Race is set to begin on March 15 and promises high adventure-both sailing-related and cultural-for the sailors lucky enough to be participating in this historical-and for now legal-race. I talked with Chris Woolsey, regatta chair of the Miami to Havana Race and SORC race chairman, to learn more about this exciting race to Cuba.
Posted on 13 Mar
Gladwell's Line - Of Carnage, Characters and Colour
About this time of an America's Cup season, the sap begins rising as new boats are launched About this time of an America's Cup season, the sap begins rising as new boats are launched, and Cup fans get their first sight of the various team designers' response to the latest America's Cup Class rule. In the monohull days, of course, we initially only got a partial glimpse thanks to the shrouding practices adopted by all teams to hide the nether regions of their America's Cupper
Posted on 13 Mar
Caleb Paine on winning a US Sailing Rolex Yachtsman of the Year Award
I talked with Caleb Paine about his recent US Sailing Rolex Yachtsman of the Year Award and about his Olympic plans. On August 16, Caleb Paine broke the longest-running medal ceremony dry spell for American-flagged Olympic sailors since the 1930s when he captured a bronze medal in the Finn class at the Rio 2016 Olympics. I recently caught up with Paine on the phone to talk about his proud US Sailing Rolex Yachtsman of the Year Award and about his future sailing plans.
Posted on 10 Mar
A Q&A with Lloyd Thornburg about his love of fast boats and racing
I recently caught up with Thornburg to learn more about his program, and to gain insight into racing MOD70s offshore. Not too many world-class sailors hail from the high deserts of Santa Fe, New Mexico, but Lloyd Thornburg isn’t your average sailor. The 37-year old investor flies the New York Yacht Club’s burgee from his fleet of raceboats that have included a Gunboat 66, a MOD70, and a Farr 280. I recently caught up with Thornburg to learn more about his program, and to gain insight into racing MOD70s offshore.
Posted on 8 Mar
So what’s it really like?
For ages now, these editorials have talked about multihull this, record that, outrageous boat speed and 24-hour runs For ages now, well it seems like that anyway, these editorials have talked about multihull this, record that, outrageous boat speed and incredible 24-hour runs. In their own very unique way they totally represent the technical avant-garde, and thank God for that. Where would we be without their impressive shapes, wonderful rigs, and now of course, foiling magic.
Posted on 6 Mar
JJ Giltinan 18ft - Kiwi Champion the subject of two protests in Sydney
Overall series leader Yamaha will have her position put on the line in a series of protest hearings on Friday Overall series leader Yamaha will have her position put on the line in a series of protest hearings Friday morning in Sydney. She faces two claims - both from Appliancesonline (David Witt). The first is an attempt to re-open the Hearing held on Wednesday morning after Yamaha was suffered damage in Race 3 as a result of a collision with a give way yacht, and Yamaha received redress of average
Posted on 3 Mar
A Q&A with US Sailing’s Malcolm Page about the Sailing World Cup Miami
I spoke with Malcolm Page, US Sailing’s Olympic chief, about the team’s performance at the 2017 Sailing World Cup Miami I talked with Malcolm Page (AUS), a two-time Olympic gold medalist in the Men’s 470 class and the chief of Olympic sailing at US Sailing, to get his pulse on the team’s performance at the 2017 Sailing World Cup Miami and discuss some recent coaching changes within the Olympic-sailing program.
Posted on 20 Feb
America's Cup - Emirates Team NZ give first look at the pedaling AC50
Emirates Team New Zealand formally christened their new AC50 America's Cup Challenger on a rainy Auckland afternoon. Emirates Team New Zealand formally christened their new AC50 America's Cup Challenger on a rainy Auckland afternoon. The team has been sailing for the previous two days making news headlines after it was revealed in Sail-World.com that the AC50 would become only the second yacht in America's Cup history to use pedal power.
Posted on 16 Feb