What is a Light Air Sail?
A light air sail is a large unsupported headsail designed to increase the speed of vessels sailing in light winds. Light air sails resemble parachutes, and they work in a similar way. Light air sails are attached to the boat, and some aren't supported by a boom or other structural device. They catch the wind and pull the boat along from the front.
Light air sails are akin to wind-powered tow lines. They're often significantly larger than the jib, and they are usually constructed from lighter and less durable material. This normally isn't a significant issue, as sailors rarely deploy light air sails when high winds would pose a risk to them.
Light air sails are all about efficiency. A light air sail can basically double the effective size of your sail plan without adding to your hull length or mast height. This is why, when using a light air sail, it's not uncommon for sailors to achieve nearly double the speed they had before deploying.
Light air sails are often tricky to use and get used to. This is because of their size and how they rig up to the boat. They're not as structurally supported as mainsails, meaning you have to pay careful attention to the wind direction and your heading before deploying one. The same rule applies while you're using a light air sail, as it's easy to get your sail tangled in the rigging or torn.
Light Air Sail Benefits
Speed is the primary benefit of using a light air sail. As we mentioned previously, a light air sail can help you nearly double your speed in light winds. This, in turn, can help you save fuel and reach your destination twice as fast.
As you might expect, light air sails are also popular with racing crews who use them in much higher winds. Deploying one at a regatta is a guaranteed boost if the conditions are ideal, and virtually all racing sailboats have one aboard.
That said, racing isn't the only practical application of light air sails. These useful sails can make it possible to go sailing on warm, calm summer days when the wind wouldn't normally be strong enough to get you anywhere. With a light air sail, you have access to the water on days with the most pleasant weather.
Eliminate your Fuel Bill with a Light Air sail
The prospect of greatly reducing your fuel bill is attractive, and a light air sail is the most practical way to do it. And while it's true that it's easier to just lire up the engine, learning to sail with a light air sail can save money and add a new rewarding aspect to the sailing experience,
But how much money can you actually save with a light air sail? The answer is quite a lot. A light air sail works for free all day, and it can save many engine hours on light-wind days.
Is It Hard to Use a Light Air Sail?
Light air sails appear to be intimidating, especially to novice sailors. It's true that light air sails can be tricky to set up and use, but they're not significantly more frustrating than anything else on a sailboat. If you can learn to sail without one proficiently, then you can learn to sail with light air sails.
Types of Light Air Sails
There are many types of light air sail arrangements out there, and each has its own benefits and drawbacks. The most common types of light air headsails are the spinnaker and the genoa. First, we'll focus on the spinnaker.
A spinnaker is the type of sail most people think of when they picture a sailboat gliding along in light winds. Spinnakers are a lot like parachutes, and they are up ahead of the jib and often over the water.
The genoa is a traditional type of light air sail. This sail is almost always much smaller than a spinnaker. It functions as a second jib and increases the sail area of your existing sail plan. At one point, many sailboats included a genoa as an integral part of the sail plan. While not as common anymore, genoa sails are still a viable option for light wind sailing.
Spinnakers and genoas are themselves broad categories of sails. They each have several derivatives, and it's important to know the difference. Next, we'll go over the most common types of genoa and spinnaker light air sails. We'll also provide detailed information on each, so you can choose the right sail, plan for your area, and sailboat.
Genoa Types and Characteristics
If laid flat on the ground, it'd be easy to confuse a genoa for a jib. They rig up in the same place, and they perform similar functions. A genoa is a type of headsail that extends further aft than a jib, effectively increasing the sail area of your boat.
A genoa can perform the same function as a jib. This is especially true if you utilize a roller-furling mechanism. Anyone who is familiar with how to rig and reef a jib can comfortably handle a genoa.
Additionally, a genoa can be used with another headsail, increasing your light wind sailing capabilities further. One of the drawbacks to the genoa (when compared to the spinnaker) is that the genoa adds a comparatively small amount of area to the sail plan. This isn't always a drawback, as it allows you to use a genoa in a much wider range of wind conditions.
Some vessels sail almost exclusively with a genoa, as it's a versatile sail that's relatively easy to manage. If you want to increase your light air performance without drastically altering your sail plan, then consider adding a genoa to your headsail collection.
Parts of a Genoa
The parts of a genoa are very similar to the parts of a jib. After all, a genoa is really just an elongated jib. The base of a genoa is called the foot, and it runs forward to the tack and aft to the clew.
From the clew corner, the leech runs vertically to the top point of the sail, which is known as the head. The longest side of the genoa is called the luff, and it runs from the head to the tack.
The forestay, which is part of the sailboat's standing rigging, runs right along the luff of the genoa. The head of the genoa attaches to the mast, and the sheet attaches to the clew. The tack mounts to the bow or to the end of the bowsprit. Rigging a genoa gets a bit more complicated if you're using it with another light air sail, such as a spinnaker.
Spinnaker Types and Characteristics
A spinnaker is a lightweight parachute-like sail designed for light wind sailing. The spinnaker is primarily useful for downwind sailing, and it isn't structurally supported by anything other than a spinnaker pole and rigging. A spinnaker pole isn't a boom, despite resembling one.
The spinnaker pole holds out one end of the sail and serves as a pivot point. Thus, this feature keeps the spinnaker from being totally unsupported. However, not all spinnakers use poles.
Spinnakers work best when the wind is 90 to 180 degrees off the bow. Spinnakers are also known by other names, the most common of which is "chute" or "kite."
There are several distinct types of spinnaker sails. The most common types are symmetrical spinnakers, asymmetrical spinnakers, and cruising chutes. The terms "symmetrical" and "asymmetrical" refer to how the spinnaker is used and how it is shaped.
Parts of a Spinnaker
Spinnakers are complex sails with many parts. They mount to the mast at the head and to a spinnaker pole at the tack in the bottom port side corner. The control lines connect to the tack in the port corner and the clew in the starboard corner.
The edge of the sail that runs from the clew to the head is called the leech, and the edge that runs from the tack to the head is called the luff. Note that the "sheet" on the port side is actually called the afterguy, as an additional sheet called the lazy spinnaker sheet is sometimes also used.
A line called the foreguy runs from the center of the spinnaker pole to the base of the mast. Another line called the topping lift runs from the spinnaker pole to the upper part of the mast.
If used without a spinnaker pole, rigging a spinnaker can be quite simple. Using this method, you can rig the tack line to the bow and run it to the cockpit and draw the sheet all the way aft. Some spinnakers, known as parasailers, are specifically designed to be run this way.
Asymmetrical Spinnakers
Asymmetrical spinnakers are a type of light air sail that works almost like a combination between a spinnaker and a jib. It is flown from a pole and pulls primarily to one side. In other words, it powers the vessel on a one-sided asymmetrical axis.
Asymmetrical spinnakers are designed to provide the most power when sailing on a broad reach rather than directly downwind. This type of sail isn't the classic spinnaker. Rather, it became popular during the middle of the 20th century on fast racing craft.
Asymmetrical spinnakers have two sheets attached to the corners of the sail. The sheet layout is similar to a traditional jib, and it's relatively easy to control if you're experienced with headsails.
Symmetrical Spinnakers
Symmetrical spinnakers are what you think of when you hear the term "classic spinnaker." This type of spinnaker has been around for a very long time, and it's probably the most popular type of light air sail ever used.
Symmetrical spinnakers are a lot like parachutes, and they're sometimes unsupported by anything other than rigging. They fill with wind and bow out past the jib, and they're used exclusively for downwind sailing.
Handling asymmetrical spinnakers takes some care, as they're more difficult to control than standard headsails.
Cruising Chute
The cruising chute is a variety of asymmetrical spinnaker that's common on long-range bluewater sailing vessels. It's designed to be easy to handle, which is advantageous on sailboats with few crew members. Cruising chutes are preferred by single-handed sailors as well due to their simplicity.
Gennakers
Like the Code 0 light air sail, gennakers are a recent development that came about purely from practical experience. Fundamentally, a gennaker is a cross between a genoa and a spinnaker. It's based on an obscure 1870s sail design known as a "gollywhomper." Like the Code 0 sail, the gennaker is used primarily for racing.
This combination rigs up like a spinnaker, but the tack attaches to the bowsprit or the hull like a genoa. It's an asymmetrical sail, and it reaches greater efficiency at tighter angles. These combination sails are most useful when downwind in a run or a beam reach.
For cruising boats, a spinnaker or genoa will probably be more useful than a gennaker. These sails work optimally on precise, lightweight racing craft, and they're comparatively hard to come by. That said, some long-haul sailors have experimented with gennakers and report excellent results.
Symmetrical Spinnaker Designations
Spinnakers have designations that specify the kinds of conditions in which they can be used. These conditions range from light air to extreme air.
- 1S: Light Air Reaching
- 2S: Light Air Running
- 3S: Heavy Air Reaching
- 4S: heavy Air Running
- 5S: Extreme Air
Spinnaker designations also specify how the sail is to be used. In terms of point of sail, reaching spinnakers are used when the wind comes from some side angle, whereas running spinnakers are used when pointing directly downwind.
Spinnaker designations also specify how thick the sail material is. Light air spinnakers (1S and 2S) are made of thin, ultralight material, whereas heavy wind (3S and 4S) and extreme wind (5S) are made of more durable cloth.
Weight designation is important, as light winds may not provide the "lift" necessary to support a heavy spinnaker. Also, heavy wind can tear light air spinnakers and cause maneuverability issues.
Asymmetrical Spinnaker Designations
Like symmetrical spinnakers, asymmetrical spinnakers also have strength and wind speed designations. They follow the same basic rules as symmetrical spinnakers, with the exception of new 'Code 0° asymmetrical spinnakers.
- 1A: Light Air Reaching
- 2A: Light Air Running
- 3A: Heavy Air Reaching
- 4A: heavy Air Running
- 5A: Extreme Wind
- Code 0: Ultra Reaching Light Air
Code 0 spinnakers are essentially oversized genoas, but the IRC rates them as spinnakers anyway. Code 0 asymmetrical spinnakers are used for light air reaching. These new super-genoa sails are extremely efficient, and they've become a practical light air alternative to both traditional spinnakers and genoas.
Symmetrical vs. Asymmetrical Spinnakers
What are the advantages and disadvantages of each spinnaker type, and when should you use them? Different conditions call for different light air sails, which is why many sailors carry one of each aboard.
Some sailors choose asymmetrical spinnakers for reaching and exclusively use symmetrical spinnakers for running. This strategy, while not the only option, makes sense because symmetrical spinnakers are tricky, but they work well in straight downwind runs.
However, conditions other than the point of sail can play a more important part in the decision. Asymmetrical spinnakers have a clear advantage on short-handed sailing craft, as they're much easier to control with fewer people.
Asymmetrical spinnakers are also a popular choice for fast racing boats. Heavier displacement hull vessels, which are primarily used for offshore cruising, often opt for traditional symmetrical spinnakers. If there's room for a straight downwind run, heavy boats can achieve greater speed with a more powerful symmetrical spinnaker.
Spinnaker Poles
A spinnaker pole is simply a long, thin spar used to support one corner of a spinnaker. They can also be used on jabs and genoas, which turns them into a viable spinnaker alternative in light winds. Spinnaker poles attach to the mast and the tack of the sail.
When sailing in light winds, you will often come across boats with the spinnaker, jib, or genoa poled out. The pole makes it much easier to control the shape of the sail when the wind isn't strong; enough to shape it properly.
The term "poling out" refers to the practice of using a spar to fix the position of a normally "loose" headsail. Poling out sails is most useful when running directly downwind.
Many expert sailors recommend keeping a headsail spar on board even if you don't carry a spinnaker. It's a multi-purpose spar that's useful in a wide range of sailing conditions.
But do you need a spinnaker pole to use a spinnaker? In most cases, the answer is no. A pole isn't necessary to fly a light air sail, but it can make the process a lot easier and more controllable.
How Much do Light Air Sails Cost?
Sails are one of the more expensive aspects of sailing, and the total cost of a set of light air sails varies. Sail cost depends on the size of your boat, the type of sail, along with the material size and thickness. Some light air sails are mass-produced, while others are made by hand in specially sailmaking shops.
Pre-manufactured spinnakers are available for the most popular production cruising boats, such as those made by Catalina, O'Day, and Islander. For example, a light air cruising spinnaker for a Catalina 25 costs about $700 new. Standard "no-frills" cruising spinnakers usually cost between $500 and $2,000 for 20-foot to 40-foot sailboats.
Genoas for typical cruising sailboats usually cost about the same, though name-brand sail upgrades can cost well over $2,000. Custom sails are the priciest option, and they cost anywhere from $1,000 to $5,000 or more. That said, custom sails are often higher quality than production canvas.
Parasailers
A parasailor is a close relative of a spinnaker, and the two are often visually confused. The parasailor is actually designed for use in heavy winds, unlike the spinnaker. In winds up to 40 knots, a parasailor can be used to generate lift and keep the bow from diving too deep into the waves.
Parasailers are designed primarily for downwind sailing. The parasailor is a version of asymmetrical spinnaker that's usually made of stronger material. Additionally, parasailers have a wing that stretches horizontally across them, which provides lift to the bow of the vessel.
Parasailers can also be used in light wind conditions, though they really come into their own when the wind blows just a bit more than the ideal speed for a standard spinnaker.
Topsails and Staysails
Traditional gaff-rigged sailboats can use genoas and spinnakers just like modern Bermuda-rigged vessels. However, gaff-rigged sailboats have additional sails in their light air arsenal.
One of the most common sails used by gaff boats in light winds is the topsail. Topsails are essentially a triangular piece of canvas designed to fill the gap between the gaff and the extended topmast.
Topsails don't have anywhere near the sail area of a spinnaker or a genoa, but they're useful in a wide range of light wind maneuvers because they add additional thrust to the existing sail arrangement.
Staysails, on the other hand, are smaller triangular headsails that are run just aft of the jib. On schooners, they can be used in conjunction with other light air sails, such as the fisherman sail. Staysails are common on gaff-rigged sailboats, and they're often used with a topsail deployed as well.
Spinnaker Wind Speeds
What's the ideal wind speed for spinnakers and similar light air sails? The answer depends on the type of boat and spinnaker in question, but we'll cover some general advice for typical cruising boats.
For most cruising sailboats, 15-knot winds are probably the upper limit for spinnaker use. Generally speaking, sustained winds of 20 knots or greater are too high to use a light air spinnaker safely or efficiently.
These rules change for racing boats, which often deploy heavy-duty spinnakers in sustained winds in excess of 40 knots. Heavy air spinnakers, colloquially known as "chicken kites," are usable in heavier wind conditions and can help sailors achieve higher speeds.
Heavy air spinnakers, such as those in the 5S (symmetrical) and 5A (asymmetrical) category, are safer to use in wind speeds exceeding 20 knots.
Can You Use a Spinnaker Without a Mainsail?
Many sailors wonder if they can use a spinnaker or a chute sail without a mainsail. Generally speaking, this isn't usually the best idea. The mainsail provides shelter for the spinnaker when rigging and lowering, which makes it easier and safer to handle.
Keep in mind that it's best to avoid jibing when hoisting or lowering the spinnaker. In fact, people want to avoid jibing so much that they often rig up a preventer line. The mainsail can be used to shield the spinnaker from the wind, which helps prevent issues.
Rigging a Preventer Line
Preventer lines help stop accidental jibes when sailing downwind. Shifting winds and improper handling are the most common causes, and an unintentional jibe can be a real headache when flying a spinnaker.
The purpose of a preventer line is to stop the boom or sail from shifting to the other side. A boom preventer, also known as a boom brake, is a common solution. A boom brake doesn't actually stop the boom from shifting; rather, it slows the normally violent motion to a manageable swing.
The other kind of preventer line is called a jibe preventer. This prevention line permanently affixes to the back of the boom and prevents it from moving at all. Both of these preventer line systems can be manipulated from the cockpit and adjusted as needed.
