I’ll never forget the day I learned about inertia, because it almost killed me. I was working as a “dock boy” at the yacht club tossing lines and fending off as boats maneuvered into their slips. One afternoon, a 35-foot sailboat was coming in shorthanded, and a bit too fast. As its skipper ran across the deck grabbing dock lines, he let the boat coast, engine in neutral and helm untended. When it looked like the bow might hit the far comer of the slip, I braced my back against a piling and grabbed the pulpit. You know, the same way Superman would jump in front of a truck and push it to a stop. Hey, I was only 14 years old.
You can probably guess what happened. My arms were no match for the boat’s inertia. It kept on coming until the pulpit locked under my chin, lifted my feet off the ground, and caused nasty crunching sounds as it pinned my neck against the piling. Luckily, the stern line fetched taut; otherwise, I wouldn’t be here to write this.
So, what’s the lesson here? Momentum is a powerful force — a force to be wary of. But it’s also a force you can tap to propel your boat directly toward the finish. You spend all race struggling to keep your boat going at top speed, building up considerable momentum in the process. The heavier the boat, the more momentum, but even a Laser with its single crew will approach 400 pounds soaking wet. But before we talk about dinghies, let’s look at the real momentum machines: keelboats.
12-Meters: Momentum Machines
One of my favorite racing stories is that of a 12-Meter finish some years ago. I’m not sure if it’s entirely true, but here’s how it goes: Dennis Conner and archrival Tom Blackaller are sailing upwind on starboard tack, dead even, approaching the finish line in a 12-knot breeze and flat water. Both of the 60-foot, 60,000-pound monsters are slicing along at about 8 knots.
Blackaller is a boatlength shy of the starboard layline for the leeward end of the line. He can’t quite fetch, but neither can Conner, who is pinned close to leeward of Blackaller and unable to tack. To the spectator fleet, it looks like Blackaller has this race in hand. All he has to do is carry Conner past the pin, tack and then reach back to the line to take the gun. However, when Conner is about three boatlengths from the line, his bowman sprints toward the headstay. “What’s he doing?” the spectators wonder (Blackaller must have been wondering, too). As soon as the bowman reaches his destination, Conner begins to luff, and as he does, the genoa starts to come down.
“Don’t tack!” is the scream from Blackaller’s boat. “Leeward!” is the response. Conner stops his luff when he is head-towind, which (not coincidentally) also puts him on a course to cross the finish line just inside the leeward end. As Conner turns toward the finish, Blackaller, being the weather boat, has to luff to avoid a collision. But while Conner’s jib is already halfway down and hence, luffing harmlessly in front of the mast, the leech of Blackaller’s genoa plasters against his rig, acting as a brake.
Conner carries his momentum easily for the final boatlengths to the finish. Blackaller, on the other hand, begins to slow dramatically. Sure enough, Conner eases out ahead during this head-to-wind “shooting” contest to take the winning gun. There’s nothing like a 60,000-pound boat when you want to spend some momentum!
Momentum and VMG
Let’s take a closer look at how Conner saved and then wisely spent his store of momentum. His 12-Meter was charging along at 8 knots. Imagine for a moment there was a big windshift on the last beat, and now he’s close reaching into the finish. In this scenario, the windshift would put him on a course nearly perpendicular to the line, and the fastest way to finish would be to sail straight across, not shoot.
Now picture what really happened — a more typical final beat. His boat is hard on the wind, approaching the finish line on an angled course. Sure, we’d all like to be able to sail directly into the wind—directly toward the finish—but sailboats can’t sail straight upwind. However, they can use their momentum to coast straight into the wind for a short while.
When Conner is sailing upwind at 8 knots, his VMG, or speed made good directly into the wind, is barely 6.5 knots. When he shoots into the wind his VMG immediately jumps to 8 knots, because his momentum initially maintains the boatspeed at 8 knots. Then, with the sails luffing, the boatspeed and VMG drop off until eventually the boat stops dead. But every second during the shoot that the speed is over 6.5 knots, Conner is clawing farther into the wind than another boat simply sailing hard on the wind.
A 12-Meter is a very heavy sailboat. If Conner was able to shoot for 10 seconds before his boatspeed dropped below 6.5 knots, that would represent a significant gain toward the finish line. Even if he shot the line too early, spending too much of his momentum, and had to crawl across the line at a mere 5.5 knots, the initial VMG gain would put him ahead of a boat that never shot. The goal, however, is to shoot so you cross the line just as your boatspeed drops to your previous upwind VMG. For maximum gain, Conner would want to cross the line going about 6.5 knots.
This should be easy to practice, right? You just do a shoot before the race, watch the speedo, and see how far the boat carries before the speedo drops to approximately 80 percent of your upwind speed. For most boats, this will be 1 to 1.5 knots less than your upwind boatspeed. If the boat carries for two boatlengths, that’s when you should start your shoot toward the finish.
Unfortunately, this is only easy to practice when you have a good speedometer — one that can follow your dropping boatspeed as you shoot. Most speedos have a time delay, because they must average the instrument input to make the numbers appear less “jumpy” in normal straight-line sailing. This time delay — the period of averaging — is manually or automatically adjustable on a high-end speedo. If the averaging is fixed, you will find it of limited use when doing a shoot.
When to shoot
Ideally, you have a good speedo and a bowperson who can run forward and accurately signal the distance to the finish line. A few practice shoots before the race determine how far the boat will carry. When you have all of this, it’s a piece of cake. Just start your shoot at the specified distance, drop your headsail if it overlaps the shrouds, and aim on a course perpendicular to the finish line. A perpendicular course gets you there fastest, but realize that this may not be exactly head-to-wind — it depends on whether or not the finish line is square to the wind.
Now let’s look at situations that are less than ideal. Try shooting head-to-wind, and wait until the boat is stopped. Does your speedo still say you’re going 2 knots? If so, either reset the averaging or ignore the instrument. If you can’t use your speedo for feedback, then do it by feel. If you cross the line at the correct VMG, the boat always feels like you’ve shot too early — like you’re going too slow.
If you can’t stomach the uncertainty of non-digital feedback, here’s another good rule of thumb. Given the appropriate conditions, you can’t go wrong if you begin your shoot one boatlength from the line in a keelboat. Since a centerboard dinghy is lighter and carries less momentum, your “can’t go wrong” rule is modified; begin the shoot at one-half boatlength from the finish.
The appropriate condition for a shoot is in light to medium air. When it’s windy or rough, the boat won’t carry as far. If you slam a big wave on the way, you might stop shy of the line (that’s not good).
What if your bowperson is unreliable at calling the distance to the line, or if you’re sailing a small boat and no one can run forward to get a good look at the approaching finish? In this case, never, ever, shoot at the middle of the finish line. The chances of misjudging the line — and falling short of the finish — are too great. Just sail across the line closehauled, like everyone else. But even better, try to finish near one end of the line. From this vantage, it becomes obvious where the line is, so you can shoot without fear.
Another reason to finish at an end of the line is that few finish lines are square to the wind. One end is usually farther downwind, and therefore closer. If you’ve got the favored end figured out, try to approach the finish like Conner, just shy of the layline. Then shoot so you cross the line just inside the favored end. This assures the biggest gain.
Don’t worry if your momentum can’t carry you all the way clear of the line. As long as your bow crosses, you have finished. Then you can drift backward, being careful not to obstruct other boats or touch the mark at the end of the line.
The downwind shoot
Offwind, most sailboats go faster by jibing back and forth rather than sailing dead downwind. This means you will probably approach the finish line at an angle. When you have a downwind finish, you should also shoot the line. Here’s how it works.
Unless it’s windy, you’ll approach the finish on some sort of broad reach. If you’ve done a good job of planning, you’ll be on lay line for the favored end of the finish — the end farthest upwind. Instead of continuing on your angled course across the line, you’ll get across faster if you bear off, square the spinnaker, and assume a course perpendicular to the line. Just like an upwind shoot, your goal is to cross the line at the favored end, with a boatspeed that matches your previous VMG (speed made good dead downwind).
There are a few things to remember when doing a downwind shoot. First, you will carry your speed a lot longer than with an upwind shoot, so start it farther away from the line. Second, the lighter the wind, the wider the jibing angles. This means your VMG is proportionately smaller, so you can shoot longer and more effectively.
Practice makes perfect. The best way to master shooting the line is to do it at nearly every finish. Then when you really need the weapon, you’ll be able to gain valuable points. If you’re a handicap racer, just think how good it will feel to see you’ve corrected to a one-second win, and know that it was your mastery of momentum that put you there.
