Viper 640 CLASS INFO

The Viper class is gaining momentum, and Quantum’s class sails are at the front of the fleet. Our tested sail designs coupled with expert rig-tuning advice can help you meet your next challenge.

The Viper is a dynamic rig to sail. Because of that, our tuning guide is strictly that a guide. Created for a newer mast and crew of 570 lbs., you’ll want to let the Quantum tuning guide be your work-in-progress as you get it just right for your team. Don’t hesitate to call your Quantum expert for help.

Viper 640 Mainsails

Viper 640 Mainsail

Quantum’s mainsail is a full-girth sail designed to take the full range of mast bend dictated on the tuning guide. After extensive testing and evaluation, we’ve managed the mid leech to help control the full range of top end twist for powering up or depowering the sail. Includes tube bag.

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This item will be available to ship in 5 to 6 weeks

Viper 640 Headsails

Viper 640 Jib

Quantum's Viper 640 jib has been evaluated and upgraded to become the most versatile headsail in the class. It now has the power needed to go through the mid-wind range short chop, which can be tough on these boats, and still lead back and point high in the upper wind range. This sail has the spilt hanks system needed for easy handling with the spinnaker sets and take downs. Includes sail bag.

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This item will be available to ship in 5 to 6 weeks

Viper 640 Spinnakers

Viper 640 R2 Asymmetrical Spinnaker

A great bow-up sail for big fleet racing when you need to go up and over, the A2 also has the deep mode needed for light-air running. Quantum’s asymmetrical is considered the best spinnaker in the class. Includes take down patch.

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This item will be available to ship in 5 to 6 weeks

Viper 640 News And Resources

Choose a Team Member

Allan Terhune, Jr. brings an impressive resume to his job as Global One Design Director for Quantum Sails. A resident of Annapolis, he is a graduate of the United States Merchant Marine Academy, and served as a commissioned Lieutenant in the U.S. Naval Reserves. He spent two years as the Director of Basic Seamanship Training at the U.S. Naval Academy, where he managed a fleet of more than 60 boats and directed the plebe summer sailing program, teaching more than 1,200 midshipman to sail each year.

An active and accomplished one design sailor, Terhune has won 11 North American Championships – which include the Lightning, Flying Scot, and Thistle classes – has turned in top performances in the Etchells, J/80, and J/70 classes, and was the 2013 J/22 World Champion. He’s a two-time finalist for the Rolex Yachtsman of the Year (in 2008 and 2013), and was the 2007 U.S. Sailing’s One Design Leadership Award winner.

Terhune works directly with One Design owners and provides oversight for the company’s One Design program including sail development, sales and marketing, and program expansion.

  • Nationality: USA
  • Position: Global Inshore One Design Director
  • Current Town: Annapolis
Career highlights
  • Championship Finishes
  • J/22 World Championship – 1st, 2013
  • J/22 Midwinters – 1st, 2013
  • J/22 Annapolis NOOD – 1st, 2011, 2013
  • J/22 World Championship – 3rd, 2011
  • Lightning North American Championship – 1st, 2003, 2008, 2013
  • Lightning North American Championship – 2nd, 2006, 2007, 2013
  • Lightning European Championship – 1st, 2007
  • Lightning Southern Circuit – 1st, 2009
  • Lightning World Championship – 2nd, 2007
  • Lightning Midwinters – 1st, 2004, 2013, 2014
  • Flying Scot North American Championship – 1st, 2008, 2009, 2010
  • Flying Scot Midwinter Championship – 1st, 2008 2009
  • Thistle Midwinters – 1st, 2012
  • Thistle Nationals, - 1st, 2012, 2013
  • Etchells, Sid Doren Jaguar Cup – 1st, 2009
  • Etchells North American Championship – 3rd, 2008
  • J/70 DIYC #3 – 1st, 2014
  • J/70 Fall Brawl – 1st, 2012
  • J/80 North American’s (tactician) – 2nd, 2013
  • US Sailing Championship of Champions – 1st, 2004
  • US Sailing Sears Cup – 1st, 1995
  • College Sloop Championship – 1st, 1999

Farley is a lifelong, world-class sailor with more than 30 years of experience as one of the world’s top sailmakers and yacht racers. In 1985, Farley teamed up with John Kolius and started UK Sails Texas. The loft became the premier sail maker on the Gulf Coast and gained international recognition for its success in Grand Prix events. In 1996, Farley co-founded Quantum Sails and now serves as Executive Vice President.

Among his many accomplishments, Farley is a two-time member of the J/24 world championship team and has sailed aboard the winner of the Southern Ocean Racing Conference, the International 50’ class world champion, and the One Design 48 circuit season champion. He and Kolius teamed up again on the water and have won the J/80 North Americans, taking second at the J/80 Worlds.

Farley coaches many Melges 32 teams, races on RP 86 Windquest, and races his own Viper 640.

  • Nationality: USA
  • Position: Executive Vice President
  • Current Town: Seabrook
Career highlights
  • Annapolis-Newport
  • Newport-Bermuda
  • One Design 35 Circuit
  • Trans Pac
  • Kenwood Cup
  • San Francisco Big Boat Series
  • Maxi Boat World Championship
  • One Ton Worlds
  • Ultimate 30 Pro Series
  • One Ton North Americans
  • MORC Internationals
  • Japan Cup
  • Geelong Race Week
  • Block Island Race Week
  • World Match Racing Series
  • Whitby Island Race Week
  • Farr 40 AC Trails
  • J-109 NA Champion
  • TP 52 Windquest
  • Chicago and Port Huron to Mac
  • Hamilton Island Race Week
Date Class Regatta Result
Jul 26, 2015 Viper 640 Helly Hansen Marblehead NOOD 1
Jun 20, 2014 Viper 640 HYC Leukemia Cup 2, 3