Tools for a Calculated Approach
Tools for a Calculated Approach
GPS-enabled starting tools can help put your boat right on the line, but using them properly takes practice. "New Gear" from our April 2011 issue.
GPS-based devices for gauging the starting line were once the luxury of high-end programs. But the new generation of GPS units from Velocitek (at right) and RockBox (from Rock City Marine) deliver this technology at reasonable cost, and it’s really changing the mechanics of starting a race by allowing more consistent and predictable starts. For classes that allow them, GPS-enabled starting devices may reduce the number of general recalls, saving time and hassle for everyone.
I’ve used both the RockBox and the Velocitek ProStart, and they’re both very good devices. They’re easy to use, reliable, and have rapid position updating, which is critical. Remember that GPS accuracy is finite, so expect variations of up to 6 to 10 feet. Knowing this, you should exercise common sense and not rely solely on the starting unit to determine the precise line position, especially if you’re at an end of the line (see “How Close Are You, Really?” at the end of this article). I’ve found that line sights (transits) are nearly impossible to use in a crowded fleet because they’re likely to be obscured. Having an instrument that tells you where the line is can be tremendously valuable.
Using these devices is simple. First, find a good place to mount the unit on your boat, one where the helmsperson can easily read the display. Then, ping each end of the line by pressing the specified buttons on the unit. If it’s too crowded to get to these points, you can be on an extension of the line.
After you’ve pinged both ends, the units create a virtual starting line and display the distance between your boat and the line. If you’re below the line, the distance shown is perpendicular to the line, not the direction in which you’re headed. If you’re outside the starting marks, the RockBox will show the distance directly to the nearest end. The ProStart creates an infinite line passing through the two points you pinged, so it doesn’t matter where you are relative to the starting marks. It will always show your perpendicular distance to this infinite line.
Use it or lose it
Now that you have this great information, how do you use it to get a better start? First, let’s review the basics of positioning in the final minute before the start. Normally, you want to be as close to the line as possible, but still have enough distance for good acceleration. Each boat has a minimum speed that it can efficiently sail as you approach the line. This determines how close to the line you want to set up. This minimum boatspeed is unique for each boat, and also dependent on wind speed and sea state. For example, in a Melges 32, you can sail at about 4 knots in 15 knots true-wind speed and smooth water. Slower than that, and you’ll lose flow on the keel and rudder, start to slip sideways, and then need to put the bow down to create flow again. In general, the lighter the wind, the slower you can go and still maintain flow. In 6 knots of wind, the M32 can sail at about 2.5 knots and still maneuver effectively. In waves, you need to go a little faster.
On each boat I sail, I create a table of minimum speed for each condition. Then I add to that table the optimum distance to be off the line at various times before the start, say 60, 40, 20, and 10 seconds. This is the critical information you need to position your boat correctly as you approach the line, other boats aside. It’s really useful to practice starting with the GPS, and develop your table empirically from this practice.
Keep trying to go slower and higher into the wind during the period from 60 to 20 seconds, until you define how slow you can go without losing flow in each condition. Also pay close attention to how long you need to get up to full speed in the final seconds, both in time and distance. Normally, you don’t have the luxury of bearing off to a beam reach to build speed, because there are boats to leeward. So practice your high build technique, where you bear away 5 to 10 degrees below closehauled. This way, you will maintain your gap to leeward, which is critical in the minutes after the start.
If you position yourself in the way described above, you’ll have better control of your destiny, especially if you start near the middle. This is because you control the water ahead of you, and nobody will want to be ahead of you for fear of being too early. You still need to defend your space in the traditional manner, from both port-tack boats and boats reaching across your stern. But as long as another boat is not directly in front of you, you can use the high and slow technique, combined with good management of time and distance, to approach the line in a controlled way. If you can build speed at the right time, and be close to the line at the gun, you can usually live in that lane for awhile.
