Why are Mast Heights Different?
If you spend enough time around marinas, you'll undoubtedly notice the numerous masts that tower high above seemingly minuscule boats. Some are tall and thin, some are short and fat—and many are somewhere in between. So why do sailboat mast heights differ so much?
There are a lot of factors that contribute to mast height, not the least of which is boat size. Obviously, boats need a sail plan proportionate to their length, beam, and displacement in order to be efficient. The type of sail plan varies based on what the boat is used for.
Different rigs use different mast heights, even if the boat underneath is exactly the same. Let's assume we have two identical 30-foot boats. One has a tall mast and a triangular Bermuda rig, while another has a shorter mast with a four-sided rig.
The four-sided sail has a much greater area per foot of height than the triangular sail, so the mast doesn't need to be quite as high. Additionally, shorter masts can be thicker and stay within the same weight limits as a taller mast, so they can be thicker and stronger.
Average Mast Height by Sailboat Length
Now, we'll look at the average mast heights of sailboats by their overall length. We're not considering rig type beyond the fact that the majority of modern sailboats are Bermuda-rigged sloops—we'll get into that later. Here are some averages based on popular sailboats.
As you can see, the average mast height is highly dependent on the length of a sailboat. Most vessels have triangular rigs, which require a taller mast. It also seems as though mast height isn't usually far from the overall length of the boat, at least on tall single-masted vessels.
Why do Racing Sailboats Have Tall Masts?
Racing sailboats are known for their crazy mast heights and long, thin sails. There's a very simple reason for this, and it has to do with efficiency and drag. A taller and thinner sail is much more efficient for speed than a shorter and fatter sail. The same goes with the dimensions of the hull, as fast boats tend to be long and slender.
The science behind sail design is ancient and fascinating. In the 21st century, where the boat market values speed and agility, tall masts with thin triangular rigs are becoming increasingly popular. Short-masted vessels, once a key component of working offshore, are more durable but less common.
Average Mast Height of Multi-Masted Sailboats
Having multiple masts has distinct advantages, especially for cruising. Multi-masted sailboats are some of the best offshore cruisers ever built, and they are also remarkably durable. One of the main benefits of having multiple masts is that it adds a level of redundancy and increases your ability to finely control the vessel.
Multi-masted sailboats almost always have shorter and thicker masts when compared to similar single-masted vessels. Sailboats with four-sided mainsails, such as many classical schooners, are a particularly extreme example of this.
Gaff-rigged schooner masts are significantly shorter than triangular rig masts, sometimes more than 10 to 20% shorter. It's often the case that these vessels have a topmast that can be raised or lowered to add a triangular topsail, further increasing the area of the large four-sided sail plan.
What Sailboat Rigs Have Tall Masts?
Bermuda rigged sailboats (also known as Marconi rigged sailboats) are the most common tall-masted boats. Triangular rigs are tall because their sail area decreases as it moves up the sail, so they make up for it by adding height.
Fully-rigged ships also have very tall masts. These are the traditional sailing ships that are quite literally called 'tall ships' in the sailing community. They have multiple sails on each mast when fully deployed, and they usually have three or more masts and multiple headsails.
What Sailboat Rigs Have Short Masts?
The gaff rig is a common and classic sailboat rig that uses traditionally shorter masts. The gaff rig uses a square mainsail, which has more lateral area than a triangular mainsail. These vessels often deploy a topsail with or without a mast extension called a topmast.
The lateen rig is also famously simple and short-masted. It uses a triangular sail with spars that fly at an angle to the mast. It is an ancient sailing rig that was extremely common in the early days of civilization, and it served workboats across the world for centuries.
Are Shorter Masts Stronger?
Short masts can be stronger, but they aren't always. It depends on the design of the craft and is more dependent on rig type than the size of the mast itself. The strongest masts are found on gaff-rigged vessels. They are usually short and thick and traditionally made of wood.
The strength of the mast isn't so important when everything is working properly. It begins to matter in the event of a failure, like a broken stay.
A gaff-rigged vessel with a typical mast has a good chance of surviving a snapped stay as the mast can support itself. A Bermuda-rigged vessel, more likely than not, could lose its mast immediately after the standing rigging goes down.
What are Masts Made Of?
Masts are made of many different materials. Traditionally, wood was the mast material of choice. It was strong and lasted a very long time if maintained. Through the production sailboat era, when boatbuilders switched from wood to fiberglass for hulls, sailboat masts were mostly made of aluminum.
Today's high-tech racing sailboats have many more options to choose from. Composite materials, such as carbon fiber, are increasingly common due to their astounding strength-to-weight ratio. Alloy masts are also fairly common. Steel masts exist, but their use is usually confined to small sailboats and dinghies.
