by ROB CRANE
The truth of the matter is, while it’s simple to sail the boat downwind it’s difficult to do it quickly. That skill requires you to have good downwind boatspeed as well as tactics. Boatspeed, with all tactical considerations removed, can be improved simply through observation of fast sailors and practice. Tactics are more complex and more difficult to figure out on your own. I won’t broach the topic of downwind boatspeed in this article because the techniques differ dramatically from class to class. Downwind tactics, on the other hand, are similar for most boats. A review of downwind tactics can build a foundation to quickly improve the downwind aspect of your game.
Downwind tactics are simply how wind strength, wind direction, current, waves and other boats impact the fastest route to the next mark. There is always a combination of these variables in play; remember that in any given race some will have more of an impact that others. Before incorporating these variables we must first understand what route will get us to the next mark fastest in their absence. Much like upwind sailing, an indirect route will often get you there faster. The boat that sails a downwind leg fastest is the one with the highest average VMG or Velocity Made Good. The boat with the highest VMG is the one moving towards the next mark faster than the other boats – though not necessarily directly at it.
Calculating VMG requires trigonometry – which is definitely not going to happen when I race my Laser! So think of it this way: Two boats are sailing on a perfectly set downwind leg. One is going directly downwind towards the mark, sailing the shortest distance possible; the other is reaching slightly, sailing a longer course to the next leg but going faster. The boat sailing the indirect course is going faster because by sailing at a slight angle to the wind it develops apparent wind, giving it more power. If the boat sailing extra distance goes fast enough, it will cover the extra distance quicker that the other boat can cover the shorter distance, allowing it to get to the next mark first.
The trick to figuring out the best VMG while sailing is knowing what angle of sail will allow you to have the best combination of distance to sail and speed. If you sail too great of an angle to the wind, you’ll go fast but have too much distance to sail. If you sail too little of an angle, you’ll sail less distance but go too slowly. Once you have figured out what angle is ideal – it changes with conditions – then you can consider the other variables.
Next, think about wind direction. When sailing upwind, the wind shifts all the time and it pays to be on the lifted tack because you sail a shorter distance to the mark. Conversely, downwind it pays to sail on the headed jibe because just like the lifted tack upwind you’re sailing a shorter distance. It’s much easier to identify headers and lifts going upwind, and knowing which is which before you round the mark will help ensure that you sail the proper jibe downwind. After wind direction, consider wind strength – a boat goes faster in more wind.
If there’s variation in wind strength, then it’s beneficial to sail where there is more wind, provided that getting to the wind does not force you to sail a higher VMG. If you have to sail considerable extra distance to catch the puff, it might cost more to get there than you gain. After taking these variables into account, don’t forget to consider what other boats are doing. A big bunch of boats might decrease the strength of the wind on their downwind side, especially in light air. If most of the top sailors are going one way, ask yourself why. Unless you can come up with a good reason to do something else, it’s likely that they’re going the right way.
Don’t forget the current. This one you can figure out before the race. If the current is moving across the course, remember that it will require you to sail more in one direction than the other. Don’t let current take you to the point where you have to sail extra distance to the leeward mark. These concepts can be a lot to juggle, so identify which tactical consideration will have the biggest impact downwind and focus on it. As you become more comfortable, you can incorporate more factors into your decision making. As you spend more time practicing and racing, it will become easier and you will find that you start making the right decisions more often.
A member of the 2010 US Sailing Team Alphagraphics, Rob Crane grew up sailing at Noroton Yacht Club in Darien, CT. Currently in the midst of an Olympic Laser campaign, he does some coaching when time allows. Follow his campaign at RobCraneRacing.com.