It’s one of those perfect offshore nights: solid wind, easy swell, clear sky, and sheets eased on a headsail reach. The on-watch crew is active on the sail trim and you’re making gains on your competitor to leeward. Fast-forward three hours into the watch. The navigator sticks his head up the companionway and asks, “What happened to the boat that was next to us?”

“Well, the breeze continued to build and went aft a bit,” you respond. “They were able to continue sailing their course, but we were struggling with speed and had to head up to maintain pace with this headsail.”

“Why is he able to sail that angle but we cannot,” counters the navigator. “We’ve been working him all night.”

“We think they did a sail change, maybe a kite,” is your answer. “With the increased breeze, we can’t carry our spinnaker at that angle. It’s too risky.”

“Damn. I wish we’d brought a reaching kite instead of only runners,” the navigator sullenly mumbles.

If a similar conversation has ever occurred on your boat, you’re not alone. Building the ideal sail inventory for a particular distance race is one of the most important aspects of your race preparation. The best way to ensure you have the right sail for the right conditions is to recognize any gaps in your inventory, gaps that, once filled, allow you to sail the best angle possible at all times.

The first step is to take a good look at your existing sail inventory, and then define the designed true windspeed and true-wind angles of these sails. Divide your inventory into three parts: upwind, downwind, and reaching. You probably have one main, three or four headsails that cover you in light, medium, and heavy conditions, and likewise for your downwind sails. It’s the reaching sails that are more difficult to fit into the inventory. You’ve got jib tops, reachers, Code Zeros, and staysails as options, and it’s here in the reaching sails where you’ll most likely have the biggest gaps.

To give some insight into building a more versatile inventory, let’s explore a few commonly asked questions.

Courtesy of Quantum Sail Design

I need to improve my reaching inventory, but I am confused by the terminology and coding of some of the sails.
Most sailmakers refer to odd numbered sails (A1, A3, A5) as reaching spinnakers and even numbered sails (A2, A4, A6) as downwind-orientated sails. Code Zeros are most effective between 80 to 125 degrees true-wind angle, in windspeeds of 5 to 18 knots. However, it’s important to remember that the Code Zero is measured as a spinnaker. You can push these sails to slightly tighter angles in light winds, but be prepared for leech flapping. An A7 is a very small sail for very big breeze, 28 knots or more. It’s typically a fractional sail. A jib top is a high-clewed headsail used for tight beam reaching.

My boat came with a typical upwind sail inventory, but my crew insists we could use a Code Zero, especially if the race turns into an upwind drifter; is this true?
A common misconception is that a Code Zero can be used upwind in place of a genoa. In perfect conditions—light-wind, smooth water—a true-wind angle of 70 to 80 degrees is about as close to the wind as you’re going to get from a Code Zero. On a masthead-rigged boat with 155-percent overlapping genoas, the gap that exists between a large jib top and an A5 reaching spinnaker is not significant enough to warrant a Code Zero. On a fractional-rig boat with non-overlapping jibs, however, a Code Zero is a necessary sail because of the significant gap between the smaller non-overlapping jib and the A5 reaching spinnaker.