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





































Starboard Hatteras Wave Jam day 5 by American Windsurfing Tour,


















470 Men and Women Worlds - Champions decided in Santander by International 470 Class Association,












ISAF Sailing Worlds - 470 Men's medal race images by Thom Touw
ISAF Sailing Worlds, Santander - Aussies and Austrians claim 470 gold
ISAF Sailing Worlds, Santander: 470 awards images by Sail-World.com
ISAF Sailing Worlds, Santander - 470 medal race images by Jesus Renedo
Annapolis-to-Newport Race - 'What to Expect' Seminar to take place
Royal Cup Marina Ibiza - No racing on penultimate day
Belcher takes record fifth 470 World Championship
ISAF Sailing World Championships - Santander - Day 8 video highlights
2014 Great Lakes Team Racing Championship about to set off
2014 Etchells North American Championship - Day 1
2014 U.S. Multihull Championship - Day 1
2014 Chicago Match Cup - Repechage top four determined in final flight
J/24 World Championship - 35th anniversary preview
470 Men and Women Worlds - Santander medal race line-up confirmed
ISAF Sailing Worlds, Santander - Day 8 images by Sail-World.com
Royal Cup Marina Ibiza - Quantum Racing stumbles in coastal race
ISAF Sailing Worlds, Santander - Americans ready for 470 medal races
ISAF Sailing Worlds, Santander: Action ramps up with end zone in sight
Big Boat Series - It's not the size, it's the length
ISAF Sailing World Championships Santander - Double French RS:X gold
ISAF Sailing Worlds, Santander - Day 8 images by Sailing Energy   
ISAF Sailing Worlds - Finn leaders emerge from shifty Santander breeze   
ISAF Sailing Worlds, Santander - RS:X winner images by Barbara Sanchez   
ISAF Sailing Worlds, Santander - Rio 2016 470 spots awarded   
52 Super Series 2015 - Outlook looks hot for the 52 Super Series   
Starboard Hatteras Wave Jam - Another early start on day 4   
ISAF Sailing World - First entry leaves sailor's reputation in tatters   
2014 Chicago Match Cup - Four go through to quarter finals   
470 Men and Women Worlds - Champs take over leaderboard   
ISAF Sailing World Champ - Buckingham finishes with career-best result   
America's Cup: Oracle's Larry Ellison to step down as CEO   
Classic Yacht Regatta - Sonny takes top classic prize   
ISAF Sailing Worlds, Santander - Buckingham finishes with career best   
ISAF Sailing Worlds, Santander - Rio 2016 RS:X spots claimed   
ISAF Sailing Worlds - Leaderboards shaping up in Santander + Video   
ISAF Sailing Worlds, Santander - Giles Scott continues to extend lead   
ISAF Sailing Worlds, Santander - Day 7 images by Sailing Energy   
ISAF Sailing Worlds - Laser and Radial winner images by Jesus Renedo   
ISAF Sailing Worlds, Santander - Medal Race images by Sail-World.com   
ISAF Sailing Worlds - Dutch dominate Laser and Radial in Santander   


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