sail-world.com
 
 
News Home Cruising Photo Gallery Video Gallery
Sail-World.com : Rod Davis: Rethinking the Current Tactics
Rod Davis: Rethinking the Current Tactics

'Ben Ainslie Racing heads for the shore - out of the current, maybe - but not the place to be.'    © Jon Nash / J.P.Morgan BAR    Click Here to view large photo

Professional sailing coach, Olympic Gold and Silver medalist and long time America's Cup crew and skipper, Rod Davis gives his insights on the effect of current on catamarans, and the new tactics, in San Francisco.

Rod Davis on the coaching job with the New Zealand Olympic Team in Qingdao, 2008 -  Richard Gladwell   Click Here to view large photo
We are always learning in this new Cat world.

You have to think a bit more laterally when comes to racing high-speed boats like cats, particularly in current. Be it San Francisco’s America’s Cup course, or anywhere else that you try to play the current.

A few quick facts: In your 50 foot mono hull, you sail up wind at say 8 knots. If the current is 2 knots that means current is about 25% of total speed. The new Cats will sail up wind at, about 18 knots, a 2 knot the current is about 10% of the boat speed.

That is two and half times different, and is a very big deal.

When you play the shore short by tacking into the shallow water where the current is weaker, you can make big gains in your monohull. The wind shifts are a secondary consideration to getting that 25% boost in performance.

With the cat it is only 10%, so balance between current and shifts enters a different equation. On top of that, a monohull loses about a boat length in a tack.

A good tack in the cat costs you four boat lengths in smooth water, and more in waves. That's a big part of the new cat equation too. You can’t afford to short tack up shore.

The easy conclusion - no short tacking up a shore for current.

Ahhhhh, not so fast. You don’t abandon the current all together; just the current has a factor, given the new situation we are in at San Francisco sailing catamarans.

There is a mind twister: Downwind in some conditions at cat will go two knots faster with just a knot more wind speed. So, in those conditions, you would sail out into adverse current of a knot, increasing the winds speed by a knot, and boat speed by two knots, to get to the finish faster........

That's something you never purposely do in a normal boat.

Strange but true. Still learning.

Rod


When racing on courses close to shore, with current, the tactics are different for catamarans than monohulls -  Alice Gladwell   Click Here to view large photo


by Rod Davis

  

Click on the FB Like link to post this story to your FB wall

http://www.sail-world.com/index.cfm?nid=101390

11:48 AM Sun 26 Aug 2012GMT


Click here for printer friendly version
Click here to send us feedback or comments about this story.

Click for further information on
2013 America's Cup

Related News Stories:

29 Aug 2012  America's Cup World Series San Francisco a success
27 Aug 2012  ACWS San Francisco – Challenging week for Team BAR
27 Aug 2012  ACWS San Francisco - Images of Artemis Racing by Sander van der Borch
27 Aug 2012  America's Cup World Series San Francisco - Oracle Team USA double
27 Aug 2012  America's Cup: Reality check for Emirates Team NZ in San Francisco
27 Aug 2012  America's Cup World Series - Perfect day on San Francisco Bay
27 Aug 2012  America's Cup World Series San Francisco - Energy Team 4th overall
27 Aug 2012  Fisher's View: Day 5 ACWS San Francisco - Seriously speedy Sunday
27 Aug 2012  America's Cup: Louis Vuitton Cup will be stunning - Yves Carcelle
27 Aug 2012  America’s Cup World Series San Francisco - Team BAR on Day 4
MORE STORIES ...






News - USA and the World





















Express 27 National Championship overall + Video by Erik Simonson, Pressure-Drop.US,














America's Cup: Louis Vuitton Cup's Yves Carcelle dies at 66 *Feature by Richard Gladwell/Sail-World.com/nz,












Audi Melges 20 World Championship - ‘Samba Pa Ti’ crowned champion by International Audi Melges 20 Class Association,










Audi Melges 20 World Championship - Final race to decide champion by International Audi Melges 20 Class Association,










Fort Lauderdale International Boat Show - 13 things to See and do
Ronstan Bridge to Bridge 2014 - Images by Erik Simonson
Volvo Ocean Race: Update from Team Vestas Wind in images
ISAF Sailing World Cup Melbourne - Australian Sailing Team signs up
2014 18' Skiff International Regatta - Day 3
America's Cup: Oracle Team USA sailors place on world regatta circuits
Audi Melges 20 World Championship - Classic Garda conditions on day 2
PWA Alacati World Cup - Intense competition on day 3
America's Cup: 'The Doc' appointed as Commercial Commissioner
Wake Park Triple Crown - Registration open for final stop
Audi Melges 20 World Championship - Day 2 images by Stefano Gattini
Volvo Ocean Race - Two more join Dongfeng Race Team
OHPRI Teen Summer Camps make a splash
East to West: A profile of Volvo Ocean Race crew Team Dongfeng
Extreme Sailing Series - First-ever Turkish team to race in Istanbul
Audi Melges 20 World Championship - Race 4 images by Max Ranchi
New Around Britain and Ireland Monohull 40ft and less world record
Detroit Cup - Fifth place finish a difficult result for Neptune Racing
Audi Melges 20 World Championship - Alessandro Rombelli's 'STIG' leads
Volvo Ocean Race: Call of Duty comes first for Team Alvimedica
Audi Melges 20 World Championship - Day 1 images by Stefano Gattini   
Helping boaters understand weather basics   
PWA Alacati World Cup - Exciting finish on day 2   
Match 40s find the surface again + Video   
Audi Melges 20 World Championship - Day 1 images by Max Ranchi   
Clagett Regatta names first Executive Director   
Transatlantic Race - Fleet expanded for 2015 edition   
IFDS World Championship overall   
Anna Tunnicliffe: Alinghi finishes second - Extreme Sailing Series   
2014 18' Skiff International Regatta - Day 2   
2014 Audi Melges 20 World Championship - It's go time in Garda   
2nd Annual Keith Dinsmoor Regatta September 13-14   
Aldo Alessio Regatta - Three days of tight racing   
PWA Alacati World Cup - First blood to Van Der Steen and Offringa   
Oakcliff Sailing hosts the Nacra 17, 49er and 49erFX Nationals + Video   
International 18ft Skiff Regatta underway on San Francisco Bay   
Maxi Yacht Rolex Cup 2014 - Quality fleet for Maxi Classic   
Sailing Champions League - which is Europe's best sailing club?   
Weta fun at the Wine & Roses Regatta   
Extreme Sailing Series: The Wave, Muscat claims victory on Cardiff Bay   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph contact the photographer directly.
XLXL NEW US
LocalAds   DE  ES  FR  IT