Boatspeed: Musings from Course Comrade John Skinner

Boatspeed is the single most important contributor to sailboat racing success. Without good boatspeed, it is very difficult to consistently do well in sailboat races. Even if you sail a perfect course, if the boat is moving slow, it is likely that another boat sailing the same course will beat you. In addition, good boatspeed helps prevent skippers from making erroneous decisions such as taking "flyers" and sailing away from the competition.

Given that boatspeed is so important to sailboat racing, how does one go about obtaining it? Improving your boatspeed is not mysterious. With work and time, any skipper can make their boat as fast as any in the fleet.

Rigging

Santana 22 rigging has evolved over the years. Currently all of the fast boats in the fleet are rigged quite similarly. In general, you should spend some time looking at how the fast boats are set up and rig your boat the same. There are some rigging tips, however, that might not appear obvious. It is very critical that your forestay length be at the maximum allowed. This helps to induce weather helm (Santanas are notorious for having lee-helm). In addition, you should unstep your mast and file the forward part of the butt of the mast (1/8 inch is plenty) to ensure that the mast bears on the aft edge. This helps to induce bend in the mast in heavier winds when the backstay is tightened.

Now assuming that the keel and hull have been faired, the jib tracks and winches raised to the cabin top, the backstay re-rigged, all the other rigging changes have been made, and new sails have been purchased, your boat has the potential to be as fast as any in the fleet.

Tuning Up

Long before race day, you should measure your speed against a boat with similar speed. Attempting to improve boatspeed during races or even just before a races is way too late. The best way to improve boatspeed to perform parallel tests. Set two boats close together (but far enough apart to avoid interfering with each other's wind). Sail the boats long enough to determine which boat is traveling faster. The boat that is faster should mark backstay, jib fairlead, jib sheet, mainsheet, traveler, jib halyard tension, vang tension and cunningham location and then slow down to let the other boat catch-up.

Assuming the wind conditions are moderate, the slower boat should ease tension on one control (say backstay tension or jib sheet tension). The two boats should then restart the test with the faster boat trimmed the same as before and the slower boat with adjusted trim. As this process is repeated many, many times, substantial increases in boatspeed are realized by both boats. This becomes a very time consuming and tedious process that can pay off large dividends in the end. Also, it should be clear why this process does not work during races (most boats won't slow down to allow you to reset the test). In addition, the process of adjusting sails itself tends to slow a boat down. So, during races it becomes very difficult to tell if an adjustment has helped or not.

I find that in most conditions, when making a change in trim to increase speed, it is usually best to ease tension rather than increase tension. There are several reasons for this. The first reason is that the tendency to over-trim is a very common problem. As a boat sails along, it seems to be human nature to try to pull ever-tighter on controls. The second reason that easing tension generally seems to help is that it allows optimum tension to be approached from one direction. This reduces the need to "hunt" to find optimum tension. The final reason for easing is based on a generalization about performance characteristics for sailboats. Most sailboat controls slowly and incrementally increase performance as they are tightened, until they pass optimum. At this time, performance seems to decrease substantially. Thus it is usually safer to err on the side of undertrimmed than overtrimmed. When all of this things are reasons are put together they lead the simple axiom that "when in doubt, let it out". This is a good rule of thumb for trimming.

Heavier Winds

As wind speed increases, most adjustments must be tightened. Up to about 15 MPH wind speed the objective is to translate increasing wind velocity into increased horsepower to the boat. This is done very simply by maintaining airfoil shape. For example, as wind increases, draft tends to move aft. Pulling on the cunningham returns mainsail draft to its correct location (somewhere between 30% and 50% back from the mast). Increasing jib halyard tension returns jib draft to its correct location (25% to 30% behind the forestay). The challenge is to determine the correct combination of controls (which all interact with each other) to provide maximum horsepower to the boat without overpowering.

The optimum combination of backstay, cunningham, jib halyard, outhaul, tension, combined with proper mainsheet and traveler location, jib fairlead, and jib sheet location must be found for each wind and sea condition. Backstay adjustment affects both mainsail and jib shape. Tightening the backstay moves jib draft forward and decreases headstay sag up to a point after which further tightening increases headstay sag. Tightening backstay also causes mast bend which flattens the mainsail and moves draft aft.

As wind increases, I first tighten the backstay. I have marks on my backstay indicating 250 lbs. of tension and 900 lbs. of tension. I start with the lower end in very light winds. At about 500 lbs. tension, I am transferring maximum horsepower from rig to the boat. This is the setting for about 15 MPH of windspeed when the crew and skipper at maximum hike, but the boat is not over-powered. I then make all other adjustments to coincide with the backstay setting. As wind increases further, the objective is to begin de-powering the boat. I increase backstay tension up to the maximum amount and I let the traveler out. I often let the traveler out and pull it back in heavy winds to coincide with puffs and lulls. It is very important to quickly de-power the boat in heavy wind puffs. Healing over too far really slows a boat down (they start to slip sideways). "Feathering" the boat, that is steering into the wind and luffing the jib during puffs, and falling back off to gather momentum, becomes a predominant steering technique. The best way to acquire and develop this technique is to spend time tuning up with another boat.

As wind increases further, above 25 to 30 MPH, conditions shift to "survival". In these conditions my primary objective is to avoid breaking something. The tools described above are still used, just more aggressively. The only additional tool is that I may begin playing the mainsheet in puffs and lulls in addition to the traveler.

During racing conditions, I find it very challenging to judge exactly how quickly to begin making these changes. Very often ultimate success depends on correctly judging exactly when and how much to make these changes as the wind increases. It is very interesting to observe two boats essentially moving at the same speed and then to see drastic changes as one boat correctly responds to changes in wind speed while the other does not.