how to trim sails on a sailboat

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HOW TO TRIM LIKE A PRO

Everything you need to know.

One of many key positions on a race team, the sail trimmer takes responsibility for optimizing sail performance. While the most important time to shine is during the race, a good trimmer knows that success starts before the boat leaves the dock. Read these tips from North Sails expert Sam Richmond, who moonlights as trimmer on Maxi 72 Jethou and Fast40+ Ino , and learn why attention to detail makes the difference between “good” and “great” in every situation.

Guidelines for Good Sail Trim

Power from your sails comes down to three sources: Angle, shape, and twist. A trimmer’s job is to achieve the most amount of power, while keeping in mind the balance of trim between sails.

• Angles: Pull the sail in to add power and ease the sail out and to reduce power. Heading up will also reduce the power, whereas if you trim on or bear away you increase this. This is a common technique for the starting line.
• Sail Shape: deeper sails generate more power. Flat sails generate less power and also create less drag. Depth is adjusted in a few different ways; sheet tension, forestay and backstay tension and lead/jib car position.
• Twist: A closed leech will generate more power where as a twisted, open leech spills power. Twist is controlled with lead/car position and sheet tension.

Calibration

Always carry a wet notes pad to make notes onboard. Record everything from the conditions, rig tune, and sail trim, and be sure to include true wind speed and angle for reference. This will give you a foundation to base your decisions on, and provide a guide for making changes and improvements with your team.

Every line that can be adjusted needs a mark – use your marks to re-create settings that were fast. Aside from your sheets, think of your jib car position, in-hauler, outhaul, cunningham, halyards, traveller and backstay. These all affect the way your sails behave so try different settings until you find the sweet spot. Once you’ve found the groove, mark the line so you have a place to work from, and you know where to set it without hesitation.

When using an asymmetrical spinnaker, mark your sheet at the point where enough is pulled forward to prevent the windward sheet from going tight on the hoist. On a symmetrical chute, mark the guy so you know the foreguy/pole can still go up. Mark the inboard end of the pole on the mast so you can gybe as soon as possible if if you need to.

At the leeward mark, remind the pit person to hoist the jib and set the backstay to the mark you’ve made. This will allow for a smooth, clean mark rounding. Thinking about these things ahead of time allows the crew to focus on boat speed as soon as you round, while other competitors are struggling to get the set up correct for the next upwind.

Best Practices

The headsail trimmer should be constantly monitoring performance by using comparison tools onboard. Comparing your boat to other boats, target boat speeds and angles, how are “we” doing compared to just when we last made a change, and the feel of the boat. A good trimmer can feel a loss of power in the boat before it shows up as a loss of speed.

Take photos of your sails and send them to us so we can analyze the sail shape, compare them to new ones, and show you where improvements can be made. It is much easier to do this in the pre-start routine and shouldn’t be done during the race.

Communication is key. Making constant trim adjustments to improve or maintain performance, the trimmer must also communicate the current state of performance to the crew, suggesting how to improve, and reporting progress as adjustments take hold. Constant communication will keep your team attentive and working together. For example, if you encounter a lull in pressure, it would be common for a trimmer to call for the backstay to be eased. The mainsheet trimmer knows he needs to ease the sheet and the jib trimmer will ease too, while the helm “falls off” to help get the boat going again. Perhaps at the same time, the crew moves their weight to windward to help bear off.

Small efforts make a big difference in getting your boat back up to speed first. These constant changes or “transitions” in sail trim and crew weight placement can be the difference between the best and the rest.

Sail Changes

When conditions put you at a crossover between sails, a few extra factors come into play. Most notable are sea state, trending conditions, and past experience. In waves or chop you may opt to use the larger of two headsails for extra power when driving up and over waves. In flatter water a smaller sail can enable you to sheet harder and therefore point higher.

Consider the weather forecast and the conditions you have experienced up to the decision point. Are you anticipating the breeze to build up, drop off or shift? Also keep in mind that in a building breeze the sea state may remain flat, but in a dying breeze there will be leftover swell and power may still be needed.

As you gain experience with a specific boat and sail inventory, your notes on past performance will inform your decision on what sail to use. For example, in flatter water you may choose to use the J2 down to 8 knots, but as the chop builds, the J1 may be a bit faster with the slight increase in pressure. If time allows, you can try both options before the race and choose based on how the boat feels when testing your straight line speed.

Never Relent

A trimmers job is never done. Don’t cleat it and certainly don’t hang out to leeward! The jib trimmer will be the last of the crew to the rail, so only stay to leeward if conditions allow. Once the crew is fully hiked out, the trimmer should hike too, and take the tail of the sheet with you so you can ease quickly if you need to without leaving the rail. Keeping the boat flat in pressure allows the foils to do their job.

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Guide to Sail Trimming & Shaping

Last Updated by

Capt Chris German

June 15, 2022

Sail trim and shape are pretty easy to master. By understanding and using a few key aspects of physics, you can make your boat sail not just faster, but better.

Sailing however is not all science but rather an artform. While physics can make you sail better, a good intuition will make your boat sail best.

I have seen sailors who far exceed my skill level, squeeze an extra two knots out of a boat in a dead calm breeze through the trim and shape of a sail alone. I have also seen sailors who could not sail their way out of a wind tunnel at full blast. Neither party could fully explain their success or failure.

As best I can do, I will explain the science of how a sail works and how it might be trimmed most effectively. Please do not, however, confuse me with those sailing wizards who through incantation and alchemy can compel the wind to do their bidding and win races.

Table of contents

How a sail works

Sails are nothing more than a wing. Just as a gull can twitch and flex the leading and trailing edges of a wing to maximize the effect of a passing zephyr, so can you as a sailor squeeze the most from a breeze and translate that into boat speed.

But at its core, a sail operates on two principles, lift and push.

The lift is what makes planes fly and eagles soar. The wind is diverted into two paths around a sail on the forward side and on the back side of the sail. The difference in speed and inversely pressures of those two streams is converted into force through a principle first described by Swiss Mathematician Daniel Bernoulli.

That force is communicated to the boat through the mast and that energy is transferred to the hull in a lateral direction that is redirected into forward motion through the lateral resistance of the keel on the boat which slips forward like a wet watermelon seed squeezed between your fingers.. Sounds complicated right? It is.

All you really need to know is that for a main sail to work, it needs to have a nice fluid promoting shape to it like a smooth airplane wing set on its edge and pointing to the heavens. That’s why sails need to be kind of stiff and if you pull it in too far, it slows you down and if you let it out too much, it also slows you down.

With a jib it also needs to have a nice wing shape to it, but in that case it needs to be pulled in concert with the mainsail because it enhances the flow of wind on the backside of the main. This is all under the lift principle which is mostly what is happening when you are upwind sailing.

When you are downwind sailing it's all push and no lift.

Downwind sailing and the Pirates

When I describe this subject to kids they could care less about the physics of it all and would most times rather go swimming than learn about the science of sailing.

So to catch their attention I differentiate upwind sailing or lift, by comparing downwind sailing to something they can get jazzed by, pirates. Down wind sailing or running is all push and no lift and that’s what powered the pirate boats.

Back in the days of Blackbeard and Kidd, boats were square rigged and their sails were rigged perpendicular to the boat so that they could catch the wind and the westerly trade winds could push their boat up the coast to the New World. They did not have a great ability to sail upwind because Bernoulli hadn’t quite explained to them at that point that a boat can be lifted upwind instead pushed down wind and Marconi, another guy who revolutionized sailing, hadn’t created the triangular sail yet.

When we are sailing downwind, the sails are catching wind and pushing the boat downwind. Accordingly when you are sailing upwind you are italian (due to Marconi’s invention of the triangular sail that lifts the boat) and when you are downwind sailing you are a Pirate.

The Shape of Wind

Now that we know the difference between upwind sailing and downwind sailing, we must talk about the shape of the sail. By understanding the shape of the sail, we can best adjust our sails to catch the shape of the wind. There is a shape to the wind.

On the upwind leg, the wind streams across our sails, while on the downwind leg, the wind fills our sails like a parachute. If you were to think about the shape of the wind on each leg, the upwind would be shaped like a stream of water coming from a garden hose while the downwind would be shaped like a bucket covering a much wider surface area.

And when you think about how to catch wind of each shape, you need a wider surface area to catch all the wind on the downwind leg like a parachute and a more narrow or slot shape to enhance the flow of the wind on the upwind leg, just like the nozzle of the hose.

Accordingly when we trim our sails to downwind, we go with the phrase, “if in doubt, let it out”. To catch all the wind you can on a wide surface area to push you downwind, you want as much sail out as you can get to catch the wind.

On the upwind leg, we don't have a sexy little phrase to remind you, because we just pull the sail all the way in. However, we pull the jib and the main in so that they will enhance each other and create a slot between the two to enhance the flow of the wind between them.

I hear you though, what about the points of sail in between???

On the reaches,(IE close, beam and broad), you are combining the principles of lift and push at varying degrees with more lift as you head upwind and more push as you head downwind. The trim of your sails will be in proportion to either force of lift or push, with a close reach mostly lift and a broad reach composed mostly of pushing force.

When you have the angle or trim of your sails working for you, then we worry about the finer details like shape.

Going back to that wing shape we talked about, once your sail is trimmed in the right place, we begin to look at the finer controls that might be available to us on the sail to make that perfect smooth wing like that of the seagull.

Birds have muscles in their wing that alter the angle of the feathers on the leading and trailing edges of their wing so they can fly up and down. Planes have flaps that can articulate to add lift to fly high and to slow the speed of the plane when landing. Sails have similar controls to change the angle and curve of the sail that can speed up or slow down the boat.

The curve of a sail is referred to as a camber of the sail. The more Camber a sail has, the deeper the pocket in the sail to catch more wind.

When we adjust the shape of the sail, we are deepening or making more shallow the camber of the sail. We can also change the location of the deepest pocket in the sail by moving forward or aft. Finally we can change the twist of the sail creating more of a pocket aloft or down lower depending on our needs.

To understand where these controls are on the sail, we must now talk about the sides and corners of the sail.

All Marconi rigged boats, or triangular sails, have three sides and three corners. The three sides of a sail are the leech, the luff and the foot, with the three corners referred to as the head (the top corner), the tack (the front corner) and clew (the back corner). 

The leech runs from head to the clew or top corner to the back corner. The foot runs from the tack to the clew and the luff runs from the head to the tack. All the controls on the sail change the length of each of the sides to increase or decrease the depth and location of the camber or pocket of the sail.

The lines used to change the shape of the sail have all kinds of names like leech line and halyard tension and outhaul. Every sail is a little different so I don't want you to get bogged down for now on the names of the lines, but rather focus on the theory behind the shape of the sail.

Where to put the camber

The camber or pocket of your sail will be determined by the conditions of the day and the comfort of your crew. Choppy days, heavy wind days and days with no wind at all, mandate that the shape of your sail ought to change.

The higher your camber on your sail, means the higher the center of effort is on your boat where you will catch more wind aloft. Big waves or heavy wind with a high center of effort leads to a more tippy or unstable vessel. On choppy or heavy wind days you will want to flatten your sail with a lower and more shallow pocket that is closer to the deck.

On lightwind days with smoother seas, you can ease your sail out and go with fatter pockets that are higher aloft. The best sailors can use all the controls they have available to them to take advantage of the conditions to effect the greatest speed out of their vessel or the most comfortable ride for their crew depending on their priority.

One more thing on sail shape- while you can feel and see the greatest effect on shape up wind, there are just many ways you change the shape of your sail on the downwind leg. Think about where you want the center of effort on your boat and shape your sails to your conditions. 

This is Not a Primer for Racing Boats

I decided a long time ago that racing was a great way to ruin a good day of sailing. While I am no longer a fan of racing, that doesn’t mean that I can’t appreciate your interests in the subject.

All of these tips on sail shape and trim are designed to help people who have questions about sail shape, but are intimidated by the “authorities” on sailing. Admittedly, there is a ton of info out there about how to make your boat go fast that I have not included here, that just goes over the heads of aspiring sailors. It is my hope that this has broken down the subject in a way that helps you better understand the theory of sail shape and trim.

If you are interested in using these tips to make your boat go faster to win races, then go for it. Try out a few different shapes on your boat and see what makes your boat go fastest. But for everyone else who isn’t interested in winning the Wednesday night beer can series, please know that this stuff applies to you as well.

Cruising in rough weather can be made so much more comfortable with a change of sail shape and the longevity of your sails will be improved if you trim your sails properly to the conditions. Cruising sailors would do well to try out the controls on their boat and see what happens when you ease the outhaul and tighten the leech line.

Either way, remember, do good, have fun and sail far. Thanks for reading.

Related Articles

Capt Chris German is a life long sailor and licensed captain who has taught thousands to sail over the last 20 years. In 2007, he founded a US Sailing-based community sailing school in Bridgeport, CT for inner city youth and families. When Hurricane Sandy forced him to abandon those efforts, he moved to North Carolina where he set out to share this love for broadcasting and sailing with a growing web-based television audience through The Charted Life Television Network.

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• Yachting Monthly
• Digital edition

How to optimise sail trim

• April 23, 2024

The author of Illustrated Sail & Rig Tuning, Ivar Dedekam, provides his expert advice on how best to optimise sail trim

It is difficult to describe ‘correct’ sail shape, but the three most important things to consider are: sail draft (the fullness of the sail), draft position, and twist (controlled by the kicker/vang and leech tension).

Sail draft (chord depth) is an imaginary line from luff to leech called the chord. Chord depth can then be expressed as the ratio percentage between the maximum draft (d) and chord length (c). Draft stripes or seams in the sail can be used to estimate the depth. It is quite difficult to measure, so cruising sailors will use their eyes and experience to estimate draft.

Allowing the sail to fall more out to leeward at the top than in the lower parts is called ‘twisting the sail’. Photo: c/o Fernhurst Books

Draft position

The distance from the luff to where you find the maximum draft in the sail is called the draft position. Draft forward gives a lower lift/drag ratio, and you can’t point as high as with the draft aft. But it is a more forgiving shape, making it easier to steer and giving a wider ‘groove’. The ‘groove’ is a narrow course range determined by a combination of your sail trim, boatspeed and pointing ability. Once ‘in the groove’ your boat comes alive and travels at maximum efficiency. Draft forward is therefore more suitable in rougher conditions or for a less experienced helmsman.

Draft aft gives a better lift/drag ratio than draft forward, allowing you to point higher. The sail will, though, stall more easily if the boat is not steered correctly. Draft aft sail shape is therefore best in easier conditions (medium winds and flat seas).

The shape of the sail’s entry can be critical especially for the genoa (jib), which has no mast in front of it to affect the airflow. A round entry reduces the pointing ability but is less affected by changes in angle of incidence, making it easier to steer.

Different draft positions (shown in white), illustrating their impact on sail trim performance. Photo: c/o Fernhurst Books

A fine entry allows higher pointing but is less tolerant to changes in angle of attack which makes steering more demanding. The forestay and halyard tension also have an impact on the fullness of the sail entry.

True wind speed increases with height, so the higher above deck level we measure, the stronger it gets.

Boatspeed-generated wind remains constant with height. Adding the vectors together shows that the resultant apparent wind shifts further aft and increases in strength with height. You therefore have to trim the sail in such a way that the wind’s angle of incidence to the sail will be constant from the foot to the head of the sail.

This is done by letting the sail fall more out to leeward at the top than in the lower parts, called ‘twisting the sail’. Mainsail twist is primarily adjusted by the kicking strap (kicker or vang), the mainsheet and the position of the traveller on the track. The twist of the genoa (jib), meanwhile, is adjusted by moving the sail’s sheeting point, and is affected by sheet tension.

Vertical Sail Shape

The sail should have a little more fullness in the upper parts to be more efficient. This can be difficult to judge and is of more interest to the keen racing yachtsman. Most cruising yachtsmen and many racers don’t try to fine-tune the sails vertically beyond the curvature the sailmaker has built into the sails.

But in strong winds the upper parts of the sails ought to be flattened in order to avoid excessive heeling forces. This is a common problem for most yachtsmen and usually more twist will be employed.

Airflow is bent due to the mainsail which allows the genoa to be sheeted at a wider angle to the boat’s centreline. Photo: c/o Fernhurst Books

The genoa (jib) is often considered to be the boat’s ‘engine’. The mainsail can then be seen as a kind of trim flap that gives the boat its pointing ability and controls the helm balance. This should not be taken too literally as each sail’s function overlaps with the other. Why is the genoa so important?

The genoa does not have a mast in front of it to disturb the airflow and create vortices and drag. It can be set at a wider angle to the wind than might be expected, due to the ‘upwash’.

Upwash is the change of airflow direction created ahead of a sail (or an object) before the flow has reached the sail (the object) itself. The genoa is in the main’s upwash area and benefits from a wider wind angle (gets a ‘lift’) and can be sheeted further out from the boat’s centreline.

Conversely the mainsail functions in the genoa’s ‘backwash’ and must be sheeted in harder than if it was operating alone. Trim the genoa for driving force and the main primarily to obtain a correct helm balance.

The genoas are named Genoa No.1, 2, 3, and so on, with decreasing size. Genoa 3 is effectively a standard jib. The size of the genoa is given in square feet or square metres, but it is also defined by the length of LP (luff perpendicular).

We describe genoa sizes by the degree of ‘overlap’. This is a measure of how much the sail overlaps the mast. A common value for Genoa No.1 is 150%, for Genoa No.2 130-140%, and for Genoa 3 about 100% (that is, roughly no overlap).

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Tips for Getting the Most Wind Power in Your Sails

How to Trim Sails Upwind

In this sailing basics video you learn how to properly trim sails when sailing upwind.

How to Trim Sails Downwind

In this trimming sails video you learn how to trim your sails for easy sailing when the wind is behind the boat and pushing you downwind.

Want to learn more? Take our Learn to Sail Course and learn the proper way to trim sails when sailing with the wind behind you.

How to Jibe a Sailboat

In this adjusting sails video you learn how to properly handle the sails when you move the boat through the wind. This is called jibing and when done right, there is little strain on the lines or the crew.

How to Use a Winch

In this video, Offshore Sailing School founder, Steve Colgate, shows you how to properly use a winch for trimming sails. Winches aboard a sailboat give you great purchase power. In this tip you learn how to load a winch and use it properly with safety in mind. Take a look at this video and remember these helpful hints:

• Place about three turns of the jibsheet leading from the clew of the sail around the winch drum
• Load it with one hand in a circular motion in a clockwise direction
• If you have a self-tailing winch, run the jibsheet through the self-tailing groove and jam it into the cleat on top of the drum
• Now put the winch handle in the socket hole on the top of the drum and turn it to trim (pull in) your sail
• With most winches, you must take the winch handle out when you are finished trimming so you can easily add extra turns and release the line safely without the handle getting in the way or spinning out of control

How to Adjust the Fairlead on a Loaded Jibsheet

In this video you can see an easy way to fine-tune a jib lead without having to tack or use creative knots.

• While underway, grab the lazy sheet, take it outboard of the lifelines on the leeward side, and cleat it to the midship cleat
• Transfer the load by easing the working sheet until it is slack
• Slide the jibsheet car on the track to the desired point and lock it in place
• Trim the working sheet and uncleat the lazy sheet
• Undo the cleat holding the lazy sheet and take the slack out that line

How to Handle Jib Furling Systems

In this video you learn how to furl and unfurl the jib without overworking your equipment and crew. Here are some helpful hints:

• Unfurl your jib on a reach, which allows the wind to help bring out the sail
• As the jib unfurls, keep a little tension on the furling line, using a winch or cleat, to prevent an override or help you bring the jib out partially for sailing with reduced sail area in a lot of wind
• To easily furl the jib, take all the power out of the sail by blanketing it with the mainsail on a deep broad reach

How to Remove Lazy Jacks to Easily Hoist the Mainsail

In this video you learn how to clear away lazy jacks on a cruising boat when you want to hoist your mainsail. Here are some helpful hints:

• Remove one side of the jacks
• Then steer the boat so the sail falls out on the side where the jacks have been cleared
• If you cleared the jacks on the port side, steer the boat with the wind on the starboard bow (and vice versus)
• Once the sail is hoisted, it’s easy to reset the jacks to capture the mainsail when you lower it

How to Heave-To

In this video you learn how to stop your boat underway for a lunch break or rest in heavy wind conditions, without having to douse your sails and anchor. Here are some helpful hints:

• Turn the boat slowly into the wind until the jib is fully backed
• As the sail backs, take in the extra slack in the jibsheet and over-trim the jib
• When the jib is fully backed, keep an eye on your course and wait a few moments while the boat loses way and the keel and rudder start to stall
• The boat should now be balanced and moving very slowly
• Since you may still be advancing a couple of knots, jumping in for a swim is not a good idea

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Mastering the Art of Sail Trimming: A Comprehensive Guide

by Chance | Oct 15, 2023 | Uncategorized

Sail trimming is a crucial skill for any sailor, whether you’re a seasoned skipper or just starting your sailing journey. Proper sail trim ensures your boat sails efficiently, harnesses the wind’s power effectively, and maximizes your speed and control. In this guide, we’ll take you through the method to trim your sails effectively, allowing you to harness the wind’s energy to its fullest potential

Understanding the Basics

Before we dive into the practical steps, it’s essential to have a solid grasp of the fundamental concepts:

• The Sails : Most sailboats have two primary sails – the mainsail and the headsail. The mainsail is the larger sail attached to the mainmast, while the headsail, also known as the jib or genoa, is attached to the forestay at the bow.
• Close-hauled
• Close reach
• Broad reach
• Sail Controls : Familiarize yourself with the sail controls on your boat, including the mainsheet, jib sheet, halyards, and outhauls. These control lines allow you to adjust the sails’ shape and trim.

Trimming the Mainsail

Now, let’s explore the steps for trimming the mainsail:

• Sail Position : Start with the sail raised appropriately. Ensure that the mainsail is hoisted fully and that there are no wrinkles or flogging in the sail.
• Adjust the Mainsheet : The mainsheet controls the angle of the mainsail relative to the wind. To sail close-hauled, trim the mainsheet so that the mainsail is relatively flat and parallel to the boat’s centerline.
• Fine-Tune the Outhaul : The outhaul controls the tension along the foot of the mainsail. For more power, ease the outhaul. For increased pointing ability and less power, tighten it.

Trimming the Headsail

Next, let’s discuss how to trim the headsail:

• Sail Position : Ensure the headsail is fully unfurled or hoisted, depending on your boat’s configuration. Check for wrinkles or luffing in the sail.
• Tension the Jib Sheet : The jib sheet controls the angle and shape of the headsail. Trim it so that the jib’s luff (leading edge) is parallel to the boat’s centerline.
• Adjust the Halyard : Fine-tune the headsail’s halyard to control luff tension. A tighter halyard will flatten the sail and improve pointing ability, while a looser halyard increases power but may introduce wrinkles.
• Control the Jib Car : If your boat has a jib car, you can adjust its position to fine-tune the shape of the headsail.
• Communication : Effective communication between the skipper and the crew is vital. The person trimming the sails must work closely with the helm to ensure the boat is balanced and sailing efficiently.
• Constant Adjustment : Sailing is dynamic, and conditions can change rapidly. Be prepared to adjust your sail trim as needed, based on wind shifts, boat speed, and other factors.
• Practice : Mastery of sail trimming comes with practice. Spend time on the water experimenting with different settings to understand how your boat responds.

Sail trimming is an art that combines theory with practical experience. Mastering this skill is essential for any sailor looking to optimize their boat’s performance. By understanding the basics, familiarizing yourself with sail controls, and practicing the techniques outlined in this guide, you’ll be well on your way to becoming a proficient sail trimmer. Remember, the wind is your ally, and the art of sail trimming is your means to harness its power and enjoy the ultimate sailing experience.

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• Sail trim part 3: Harnessing the wind like a pro

Seasoned sailors understand that mastering sail trim is pivotal for efficient sailing and attaining top speeds on open waters. This skill, when honed, allows for peak performance from any vessel. Dive in to grasp the nuances of professional sail trimming and adopt techniques that will set your sails just right.

Sail trimming for advanced sailors

Basics of sail trimming.

Before diving into advanced methods, it's essential to grasp the fundamentals. Proper sail trimming begins with setting the mainsail and headsails (genoa, spinnaker, jib, etc.) tight enough to prevent flex. The next step is adjusting the sail's angle to the wind for optimal airflow and maximum speed. For a basic refresher, refer to our articles on sail trim fundamentals and sail trim for more advanced sailors.

Advanced sail trim techniques

As Kyle Langford, chief trimmer for the Australian national sailing team, points out, mastering sail trimming requires strong focus, attention to detail, and significant experience. An expert trimmer needs to be in tune with the yacht to optimize its speed. They should also be able to anticipate the yacht's response to the next move based on current settings. This skill is honed with practice and considerable time on the water, often referred to as "boat hours". So, what are the key areas a trimmer should focus on?

Trim the sails for peak performance

Setting the twist.

Experienced sailors recognize the significance of adjusting the twist — the variance in angle between the sail's top and bottom. This adjustment can greatly influence a boat's speed and handling. In windier conditions, increasing speed and stability might mean allowing the lower section of the sail to slacken while ensuring the top remains tight. This reduces the sail's power, preventing excessive heeling that can slow the boat. In contrast, during lighter breezes, it's recommended to harness the full sail by tightening elements like the backstay and cunnigham, maximizing the power of the entire sail.

Trimming with the roller furling system

Adjusting the sail opening

The right sail spread allows you to position the sails at varied angles in relation to the wind. For seasoned sailors, it's vital to note that the extent of sail spread influences the yacht's steering speed and its adaptability to wind shifts. Broadening the sail opening enhances its propulsive force, yet concurrently amplifies drag. It's beneficial to test various sail angles to gauge their impact on the yacht's efficiency.

Heeling the boat

Advanced sailors are able to balance the yacht precisely to keep it stable and fast. It's about managing the centre of gravity and using the crew's weight to counteract the wind's force on the sails. In stronger winds, the crew's weight needs to be shifted to the side of the hull to prevent unnecessary heeling. In lighter winds, centralizing the weight helps maintain stability and achieve higher speeds.

Counteracting heeling on a yacht

YACHTING.COM TIP: A spinnaker or gennaker can significantly increase the speed of your boat. Find out why it's a great idea to rent a gennaker with your charter yacht.

More tips for advanced sailors:

Pay attention to details.

The importance of advanced sail trim lies in attention to detail. Keep an eye on wind changes and weather patterns. Regularly check the tension of lines, tack points and other rigging to control and adjust the sails. Small adjustments can make a big difference in the performance. Learn from experienced sailors, watch regattas and to get inspiration to improve your skills.

Check out the most exciting regattas at the end of the year to watch professional sailors in action.

Practice and experiment

Even the best sailors never stop training. Advanced sail trimming is an art that takes practice. Don't be afraid to experiment and try different techniques and sail settings. With time and experience you will be able to recognize what works best for your yacht under different conditions.

Advanced sail trimming is a process that requires not only knowledge of theory, but also intuition and the ability to read wind conditions . If you pursue this art with dedication and care, you can optimize your yacht's performance and experience memorable adventures at sea.

YACHTING.COM TIP: For advanced trim skills, it is not only important to understand the basic physics of how sails work. You also need to know how to navigate at sea. Find out about navigational tools on a yacht .

Sail trimming is a skill that can greatly affect your sailing speed and efficiency. For advanced trimmers, it's an integral part of sailing that allows you to perform at your best and adapt to changing weather conditions. Proper sail trim requires experience, observation, a feel for the yacht and an appreciation of the conditions you are in. Last but not least, it's embodies a lifelong passion and leads to even more unforgettable sailing experiences.

We can help you choose a boat. Contact us!

Denisa Nguyenová

15 Actionable Tips to Trim Your Sails for Speed

Trimming sails correctly will make an incredible difference to your speed. This article will teach you how to trim your sails right and get the most out of your boat. Regardless of whether you are on a Wally or an inflatable dinghy with an open umbrella (trust me, the latter works).

Here go a few great tips how to add those precious knots to your sailing speed.

Tips for wind from the front:

• Pay attention to telltales
• Deep sail draft for acceleration, shallow draft for speed
• Put jib car forward in lighter winds and backward in stronger winds to keep the sail tight
• Make marks on the jib sheet to have a quick point of reference
• Have your foresail and mainsail trimmed for the same purpose

Tips for wind from the back:

• You aren't generating lift, so maximize sail area
• During dead runs, use the goosewings (butterfly) formation
• Use spinnaker pole on the genoa
• Wind in your back is less effective, consider going circa 30 degrees off course
• Avoid spilling power from the sail
• Use spinnaker, if you can

Tips for wind from the side:

• Side winds tend to be the fastest course
• Tighten the vang so that the sail doesn't spill power
• Let the vang go a bit if overpowered
• Increase the space between mainsail and foresail

Once you know how to trim your sails well, you will have mastered one of the key aspects of sailing. Let's have a look at these points in more detail.

On this page:

Tips for sailing with wind from the front, sail trim tips for wind from the back, sail trim tips for wind from the side, related questions:.

You see, it isn't all that difficult to set up the sails so that the boat somehow moves. But the correct trim will transport you from the realm of sailing fans, to the realm of sailors. One small change in the sail twist can boost your speed up a whole knot. And knowing how to do that, that's something to be proud of.

First of all, here is a little overview of how to position your sails for various wind directions. This is called 'points of sail'. Try to memorize this, as it is very basic knowledge. If you are a beginner, there is no shame in having these printed out and referring to them when sailing, until it becomes automatic.

Once you know your points of sail by heart, you are able to make the boat move wherever you want - but not necessarily at the highest speed.

So this article will go into more detail than this brief overview, it is about the more precise fine-tuning of the sails, to make sure you are getting the most out of whatever it is you are sailing on.

This is also called 'close reach' or 'going upwind'.

1. Pay attention to telltales

These are the little colorful strings on your sails. Although this tip might seem obvious, I have seen way too many sailors who just go by the picture above and pay attention to little else.

Which is fine, don't get me wrong. It gets you from A to B. And after all, as long as you're having fun, who am I to rain on your parade. But if you want to go faster, especially if you are using sails to generate lift, the airflow around the sheets is a vital thing for you to see. And since air tends to be invisible, telltales are your best friend in seeing what is going on.

2. Deep draft for acceleration, shallow draft for speed

If you imagine a sail from the bottom, (meaning you are lying on your deck, staring up) the curve in which the sail is bent is called draft. So a very tight, almost flat sail will have a very low draft and a sail that is let go and inflated like a balloon has a very high draft.

The draft can be thought of as gears in your car. If you want to accelerate quickly, say you want to pull yourself from a tack, let the sail go slightly to increase the draft.

But see this as a lower gear. Thus once you reach a certain speed, you might want to pull the sail in, making it tighter and flatter, thereby decreasing the draft.

You see what I meant about fine-tuning? The sail would work fine even if you knew nothing about draft. You would still get where you wanted to go. But if you are in a race, or if it is getting dark and the anchoring bay is still far, it pays off to have a few tricks up your sleeve.

3. Put jib car forward in lighter winds and backward in stronger winds to keep the sail tight

Jib car is the moveable point on a rail that holds the corner of your foresail in place. You can choose to pull it closer to yourself or have it further up. This will dramatically change the shape of your sail.

Why do this? Thing is, the most effective shape of a sail doesn't depend just on wind direction, but also on the wind speed. Thus if the wind is more of a breeze than wind, you want your foresail to be slightly more bent. Slower wind just can't work well with a sail that is too tight, to generate lift. This is easily achieved by moving the jib car forward (further from the helm).

On the other hand, once the winds get faster, you want to pull the jib car backwards, making the foresail tighter.

Don't ask me about the physics of this. Someday I might write a very long and boring article full of numbers and curves and diagrams that will explain why these tips work the way they do. But for now, out of respect for those who don't particularly enjoy this sort of content, (such as myself) I will keep it digestible. Knowledge of physics behind sailing does help a bit, but so does experience.

4. Make marks on the jib sheet to have a quick point of reference

This is a relatively minor tip but it does save time (and thus speed) when tacking for instance.

Contrary to its name, a jib sheet is not a sheet but a rope. It is the rope tied to the bottom corner of your foresail, one that you winch in when tacking.

I sometimes mark a position on the jib sheet so that when tacking, I can just winch the sail into a specific, predetermined point without checking the sail and adjusting the ropes accordingly. It saves a bit of valuable time, which you need, because you want your tacking maneuvers to be as fast as possible. Especially if sailing single-handed.

5. Have your foresail and mainsail trimmed for the same purpose

Look around on the other boats while sailing. Especially in areas where you can expect a higher concentration of beginners, (I'm looking at you, Croatia) you oftentimes see boats where the two sails have drastically different settings. For instance one is trimmed for speed, the other one for acceleration (as described in point 2.). Or the sails are influencing each other's air flow negatively.

So make sure all of your sails are trimmed for the same purpose. You will rob yourself of valuable knots if the sails are fighting each other. What you want to achieve is the maximum amount of synergy. Two sails set for the same purpose can together produce a higher force than each of them would individually, combined. Take advantage of that.

This is also called 'broad reach', or 'dead run'.

6. You aren't generating lift, so maximize sail area

It is good to know whether you are using the sails to pull your boat or to push it at any given moment. While sailing with the wind in your back, there is no lift generated, so the only thing you need to pay attention to is maximizing the sail area exposed to wind.

This is relatively easy to do as it is intuitive. Think of your umbrella being taken away by the wind as it slipped from your fingers and now is headed away, never to be seen again :(

7. During dead runs, use the goosewings (butterfly) formation

Dead run means having the wind exactly in your back. If that is the case, use what is sometimes called goosewings or butterfly. This means you open your mainsail on one side and your foresail on the other side so that they don't block each other and the sail area is maximized. It isn't the fastest way to travel, but if that is your course and you don't have a spinnaker, this is what you have to work with.

8. Use spinnaker pole on the genoa

If you are flying goosewings, your mainsail easily holds shape as it is held by the mast from the side and the boom from the bottom. But what about the foresail?

If the wind is strong enough, the foresail will hold shape too. But more often than not, you might want to use your spinnaker pole to keep it open. Simply attach the pole to the foresail's bottom corner from one side and to the mast from the other side.

When using the spinnaker pole like this, secure it in place. If let to its own devices, it has the tendency to swing around, which can be fatal to whoever stands in its way.

Fun fact, your boat hook can do a good job at this too. I know, I know, all the pro sailors are now booing me and throwing rotten tomatoes at my head. But especially if you rent a cruiser, there very likely won't be a spinnaker pole on your boat. So you gotta work with what you've got.

9. Wind in your back is less effective, consider going cca 30 degrees off course

As hinted before, having wind in your back is not a very efficient way to travel. There are plenty of reasons for this, some being that the boat is not that easy to steer, meaning the wind course relative to your boat changes slightly, making the sail trim less effective, the boat tends to roll…

So many sailors prefer to go about 30 degrees off course, which is so much faster that it will most likely compensate for the fact that you won't be going directly to your destination.

10. Avoid spilling power from the sail

Spilling power means exactly what it sounds like - the wind 'spilling' out of the sail thus wasting the power. This tends to happen for instance if the foresail is eased quite a bit, as it tends to 'open' in its top part.

This might happen when you open the sail to maximize the sail area exposed to the backwind, but if you overdo it, the sail might open too much, especially at the top, spilling the power.

11. Use spinnaker, if you can

The frustration with the inefficiency of the rear winds led to the development of spinnakers. These are sort of balloon-shaped sails that cover a lot of area and thus are used when the wind blows from behind. Before you do use one though, consider reading up on it a bit. Spinnakers aren't that forgiving to mistakes and have the power to flip a boat if the conditions are 'right'.

If you want to learn more about all the different sail types, we have an excellent illustrated guide with examples on just that. You can read it here .

This is also called 'beam reach'.

12. Side winds tend to be the fastest course...

...because the power of pushing and pulling (lift) are combined. So although this article is about trimming sails for speed, I can't but mention that sometimes it pays off to sacrifice sailing directly towards your destination as the gained speed can make up for it. This is especially true with side winds.

When planning your route, keep this in mind. Just as I mentioned above that sacrificing the 30 degrees when the wind is in your back might pay off, the same goes for this So rather than trying to trim the sails as well as you can, while maintaining a direct course, consider if it wouldn't pay off to instead change your heading.

13. Tighten the vang so that the sail doesn't spill power

With sailing on a beam reach, it is easy to spill power from your mainsail unnecessarily. Pay attention to it and if this happens, tighten the vang, making the sail a bit flatter.

When sailing on this particular course, the top of your jib will almost inevitably spill some wind. Consider that a necessary sacrifice and use the vang or pull the sail in to make sure the middle part doesn't start spilling as well.

Sadly, many sailboat manufacturers choose not to install the vang. You might play around with the available ropes to try to pull the boom downwards a bit to compensate, but since a vang is a vang, try to make sure your boat of choice has this installed when buying or renting.

14. Let the vang go a bit if overpowered

With winds from the side, you might easily encounter excessive healing of your boat. An easy fix (to an extent) is to do exactly the opposite of what the previous point suggested and loosen the vang slightly. As the wind spills, the force exerted on the sails will be reduced and your boat will return to a more comfortable position.

There are of course more ways as for instance reducing the sail area, but playing around with vang is one of the fastest and most readily available ones.

15. Increase the space between mainsail and foresail

Since this list began with the telltales, let's end with them as well.

With side winds, both your mainsail and foresail will be on one side. And since you will likely let the mainsail out quite a bit, the space between the two sails will tend to get smaller.

As a result, the sails might negatively influence the airflow around each other, which is something the telltales will show you. You don't want this to happen, so if it does, open up genoa slightly to increase the space. The telltales will be the best way to know you are doing a good job.

So that's it. There are of course plenty of other tips and tricks, but these fifteen are among those I used the most frequently while sailing.

The best way to get them under your skin is to go out and practice. These particular tips are best tried out with a speedometer, so watch the numbers closely and test out for yourself how these steps influence your speed.

Is there a video guide? Yes. And frankly, when it comes to sail trim, it often helps to see things on video or a picture. If you google this topic, you will find plenty of video sailing schools so check them out.

Can I test this on a simulator? Definitely. Not all will agree with me, but I think sailing simulators such as Sailaway are a great way to practice. The real thing is the real thing, but since you can't snap your fingers and appear on a boat anytime you wish, this is the next best thing.

Robert Johnson

Very informative. I have been sailing my 23.2 O’Day for the last 6 years with great joy. I have been applying the 15 steps you mentioned with out really knowing what they where. This clarified what I was doing and will help me pay more attention to the effects. Last summer I had the boat out 95 times, although not always under sail. Thanks for the info, can’t wait to get out there again. Last summer I even managed to keep up with my son-in-law’s Laser in a stiff breeze.

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Get the Most from Your Main

• By Gary Jobson
• Updated: June 3, 2010

main sail 368

While cruising in Maine with my daughter, Kristi, we made a game out of trimming the sails so the boat would sail itself. It was great fun seeing who could set the boat up so no steering was necessary for the longest period of time. We also had a friend on board who was new to sailing. Our game turned into a lesson on trimming sails, and in the process we relearned that trimming can be great fun.

The mainsail on every sailboat is a versatile partner that should be used at all times while under way. On most modern boats, a second or third sail is usually set along with the main, but the latter is occasionally used alone. No matter the arrangement, it’s important that the main be trimmed properly. In general, correctly trimmed sails help the boat to sail faster and stay in balance and make the boat safer to be aboard. Proper trim also helps to preserve the sailcloth, keep the crew engaged, and even provides shade on a sunny day.

Before you start trimming, make sure that all lines, blocks, the traveler, fittings, and the mast and boom are in good working order. Any flaw in the system can cause a problem. A periodic check is worth the effort. I replace my sheets every two years.

The basic theory of trimming is simple: In light wind, a curved sail with lots of shape is faster, but as the wind speed increases, the sail needs to be flattened to reduce its power. To make trimming easy, I use indicators to help me get the best shape. My favorite indicators are telltales, the angle of heel of the boat, and the position of the draft on the sail.

A series of telltales along the leech of the main should flow evenly. If the top telltale stalls and curls around the back of the sail, the sail is trimmed too tightly. Another helpful indicator is to position yourself so you can sight up the sail, from below the boom, and line up the top batten with the boom. If the batten hooks to windward, the sail is trimmed in too hard. If the batten appears to fall off to leeward, the sail isn’t trimmed in tight enough. Draft refers to the curvature or fullness of a sail. The maximum draft should be positioned about half of the way aft in the sail. When you take tension on a sail, the draft moves in that direction: If you want to sail closer to the wind, trim the sail in to move the center of draft aft. For more speed, ease the mainsail out, which moves the draft forward.

Small adjustments are important. A leech that’s flapping is inefficient and destroys the sail fabric. Keep the leech held tight by adjusting the sail’s leech line. And if your boat has one, make sure that the topping lift is well eased. The weight of the boom and sheet should be on the sail, not on the topping lift.

Most boats benefit from a boom vang, which keeps tension on the mainsail’s leech. In strong wind, be careful not to overtrim the vang; there’ll be no forgiveness in the sail, and the boat could spin out of control. The boom vang is most effective when sailing downwind to keep the sail and boom from flopping randomly, which can be dangerous.

If the wind picks up while you’re sailing closehauled and the boat starts to heel over, making it difficult to handle and uncomfortable for the crew, it’s time to depower the mainsail.

As the breeze builds, here are the steps that I’d suggest taking to depower the main, in the order that I follow on my boat: First, flatten the sail by tightening the outhaul and downhaul. Next, if your boat has an adjuster, tighten the backstay to put a slight bend in the mast; this makes the mast conform to the curve of the sail, which flattens the sail. Next, I’d suggest dropping the traveler to leeward to reduce the pressure on the main. The amount of pressure on the helm and rudder-weather helm-is a good indicator of a properly adjusted traveler. Boats tend to sail most efficiently when there are 3 to 5 degrees of windward helm applied.

You can also ease the sail to twist the top of the leech to leeward; this relieves pressure and reduces heeling. And finally, take a reef in the sail to reduce the amount of area. If you do take in a reef, it’s important to take your time and secure the sail carefully. Make sure the reef points gathering up the excess sail are tied with a reef knot that’s easily undone. Tie a reef knot, also called a square knot, so that one finished end is a bow that can be untied quickly.

With good care, mainsails can last several years. When not in use, keep the cover on to minimize sun damage. Fold the sail neatly, check for chafe, and wash it occasionally with fresh water.

Using these basic trimming techniques will provide comfortable, efficient, and fun cruising on boats of all sizes.

Backwind TIP • Closehauled, a jib will sometimes backwind the mainsail, causing it to luff along the leading edge. This is normal; if there’s 1 to 2 feet of backwind, your trim is likely fine. If there’s a lot of backwind, the jib may be overpowered; try moving the jib-sheet lead aft or outboard. You can also try rolling in a portion of the jib.

Gary Jobson, a CW editor at large, is a sailing commentator on ESPN, a former America’s Cup racer, a frequent cruiser, and the president of U.S. Sailing.

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Video shows moments before superyacht went down in storm off Sicily

Newly released video captures a luxury superyacht being battered by a violent storm before it suddenly sank off Sicily with 22 people aboard Monday.

The grainy images obtained by NBC News and other outlets were recorded on closed-circuit television not far from where the Bayesian was anchored, about a half-mile from the port of Porticello, on Sicily’s northern coast .

The yacht's 250-foot mast, illuminated with lights and lashed by the storm, appears to bend to one side before it finally disappears and is replaced by darkness.

The speed with which a yacht built to handle the roughest seas capsized stunned maritime experts.  

“I can’t remember the last time I read about a vessel going down quickly like that, you know, completely capsizing and going down that quickly, a vessel of that nature, a yacht of that size,” said Stephen Richter of SAR Marine Consulting.

British tech tycoon Mike Lynch and five of the 22 other people who were aboard the 184-foot vessel remain unaccounted for and are believed to be trapped in the Bayesian’s hull, nearly 170 feet underwater.

Officials confirmed Monday that at least one person, the ship’s cook, had died.  

Superyachts like the Bayesian, which had been available for charters at a rate of $215,000 a week, are designed to stay afloat even as they are taking on water to give the people aboard a chance to escape, Richter said. 

“Boats of this size, they’re taking passengers on an excursion or a holiday,” Richter said. “They are not going to put them in situations where it may be dangerous or it may be uncomfortable, so this storm that popped up was obviously an anomaly. These vessels that carry passengers, they’re typically very well-maintained, very well-appointed.”

Built by Italian shipbuilder Perini Navi in 2008, the U.K.-registered Bayesian could carry 12 guests and a crew of up to 10, according to online specialist yacht sites. Its nearly 250-foot mast is the tallest aluminum sailing mast in the world, according to CharterWorld Luxury Yacht Charters. 

On Tuesday, Italian rescue workers resumed the search for Lynch and the five other passengers still missing: Lynch’s 18-year-old daughter, Hannah; Morgan Stanley International Chairman Jonathan Bloomer and his wife; and Clifford Chance lawyer Chris Morvillo and his wife.

“The fear is that the bodies got trapped inside the vessel,” Salvatore Cocina, the head of civil protection in Sicily, told Reuters .

The Bayesian is owned by a firm linked to Lynch’s wife, Angela Bacares, who was one of the 15 people rescued Monday after it capsized.

“It’s extremely rare for a boat of this size to sink,” Richter said.

What’s not rare is the kind of storm that sank it , said Simon Boxall, senior lecturer in oceanography at Britain’s University of Southampton.

“People assume the Mediterranean is this rather calm and passive place that never gets storms and always blue skies,” Boxall said. “In fact, you get some quite horrendous storms that are not uncommon at this time of year.”

The president of Italy’s meteorological society has said Monday’s violent storm may have involved a waterspout, essentially a tornado over water, or a downburst, which occurs more frequently but doesn’t involve the rotation of the air.

Luca Mercalli, president of the Italian Meteorology Society, also said recent temperatures may have been a factor. 

“The sea surface temperature around Sicily was around 30 degrees Celsius [86 Fahrenheit], which is almost 3 degrees more than normal,” Mercalli told Reuters. “This creates an enormous source of energy that contributes to these storms.”

The Mediterranean sailing vacation was designed to be a celebration for Lynch, who two months ago was acquitted by a San Francisco jury of fraud charges stemming from the 2011 sale of his software company Autonomy to Hewlett-Packard for $11 billion.

Prosecutors alleged that Lynch, dubbed “Britain’s Bill Gates,” and Autonomy’s vice president for finance, Stephen Chamberlain, had padded the firm’s finances ahead of the sale. Lynch’s lawyers argued that HP was so eager to acquire Autonomy that it failed to adequately check the books .

Lynch had taken Morvill, who was one of his defense attorneys, on the luxury trip. 

Chamberlain was not on the Bayesian.

In what appears to be a tragic coincidence, a car struck and killed Chamberlain on Saturday as he was jogging in a village about 68 miles north of London, local police said.

“Steve fought successfully to clear his good name at trial earlier this year, and his good name now lives on through his wonderful family,” Chamberlain’s lawyer, Gary Lincenberg, said in a statement .

Henry Austin reported from London and Corky Siemaszko from New York City.

Henry Austin is a senior editor for NBC News Digital based in London.

Corky Siemaszko is a senior reporter for NBC News Digital.

Sailing yachts like Mike Lynch's are 'unsinkable bodies', CEO of boat manufacturing firm says

Bayesian superyacht which sank off Italy is an "unsinkable" vessel, Giovanni Costantino, CEO of The Italian Sea Group, said.

By Ashna Hurynag, news correspondent and Eleonora Chiarella, producer

Sunday 25 August 2024 08:48, UK

Vessels like Mike Lynch's stricken superyacht are "unsinkable", according to the chief executive of the firm which makes and sells them.

Giovanni Costantino, CEO of The Italian Sea Group, told Sky News there are no flaws with the design and construction of the Bayesian superyacht which capsized in a storm off the coast of Porticello, Sicily, on Monday.

Five bodies were found by divers on Wednesday - taking the number of confirmed dead to six.

The Italian Sea Group also owns the firm that built British tech tycoon Mr Lynch's Bayesian, and Mr Costantino said the vessels "are the safest in the most absolute sense".

"Being the manufacturer of Perini [boats], I know very well how the boats have always been designed and built," he said.

"And as Perini is a sailing ship... sailing ships are renowned to be the safest ever."

He said their structure and keel made them "unsinkable bodies".

Read more on this story: Why search of superyacht wreck has been so difficult Hero mum 'slept with baby on deck when storm sank yacht'

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Mr Costantino said news of the sinking "put me in a state of sadness on one side and of disbelief on the other".

"This incident sounds like an unbelievable story, both technically and as a fact," he said.

It is understood Italian prosecutors investigating the incident are continuing to hold interviews with the survivors.

On Tuesday they questioned the captain for more than two hours to help reconstruct what happened and provide useful technical details.

Four British inspectors are also in Porticello and have begun a preliminary assessment of events.

It is understood they will look at all relevant aspects of the incident, including the design, stability, and operation of the vessel. They will also examine the effects of the weather conditions experienced.

Keep up with all the latest news from the UK and around the world by following Sky News

Twenty-two people were on board the vessel, 15 of whom were rescued - including Briton Charlotte Golunski and her one-year-old daughter Sofia.

Divers will resume efforts on Thursday morning to bring ashore a body they found earlier. One more person remains missing.

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Home > Innovation  >  Mobility

How Energy Observer Set Sail with a Toyota Fuel Cell

What an Around-the-World Experimental Ocean Voyage Taught the World About Hydrogen

Five years ago, Toyota answered a call inquiring about its hydrogen-powered fuel cell technology from Energy Observer, an experimental ocean-going catamaran with a mission to circle the globe using only renewable energy. Thoughtfully built as the first hydrogen-powered, zero-emission vessel to be self-sufficient in energy, Energy Observer’s mission was to advocate and serve as a laboratory to raise awareness of renewable energy technologies available now for society’s ecological transition.

Though Energy Observer had used a hydrogen fuel cell stack from the onset, the captain, Victorien Erussard, was interested in technology upgrades as they became available. He learned that Toyota was offering a commercially available hydrogen-powered fuel-cell stack. Erussard thought that Toyota, with its reputation for making reliable and affordable cars, might have a product that could withstand the roughest conditions of the ocean. He placed a call and soon found an audience with Toyota Motor Europe (TME), kicking off discussions.

Toyota has long been exploring carbon-reducing and carbon-neutrality mobility solutions, and hydrogen-powered fuel cells are a part of its multi-pathway strategy. Toyota introduced the world to its first mass-produced hydrogen-powered fuel cell electric vehicle, the Mirai, in 2014, and the company had been discussing applications of the technology beyond cars. For Toyota, Energy Observer was an exciting opportunity to demonstrate the scalability of the fuel-cell stacks Toyota developed for the Mirai, said Luc Vercauteren, a powertrain project leader at Toyota Motor Europe.

“I was immediately struck by the adventure of it,” Vercauteren said. “Toyota has ambitions to get to zero emissions. The fact that this ship was going to tour the world was a great way to get that point across.”

Already, the versatile technology had been scaled and used globally in commercial vehicles, such as trucks and buses, and even in non-automotive applications, such as stationary power units – and now, with the help of Energy Observer, Toyota went to sea.

Not that there weren’t challenges.

As a literal floating test bed of different technologies that includes solar and wind energy capture, hydroelectric generation, and hydrogen fuel cell technology, space is at a premium on Energy Observer.

OVERCOMING OBSTACLES The Energy Observer vessel began life as a sail-powered racing catamaran. It has a cabin suspended between two large pontoon-like hulls. Different parts of the boat are connected by netting that the crew walks on to get around. It’s an extremely lightweight and efficient design ideal to use a minimum amount of energy. But it doesn’t leave a lot of extra space for equipment.

When the Toyota team went to see the space for the fuel-cell stack, they found a tiny compartment inside one of the ship’s racing hulls that was housing a washing machine. The hull wasn’t strong enough to hold a stack weighing more than 500 pounds. Systems that were originally designed to be spread around the Mirai passenger vehicle’s frame had to be repackaged into a cube-like shape fit to the exact specifications of the space. Even after that, there was no way to squeeze the stack through a tiny cargo door.

Soon, the fuel-cell stack was retrofitted by TME’s Technical Center Europe team and repackaged to withstand the challenges of an ocean environment — protected from the ravages of salty air and seawater. To install it, the boat crew had to cut a hole into the hull and would later have to patch it back together after the system was installed and working.

It’s a tight fit for the Toyota fuel cell system underneath the deck of Energy Observer. Toyota Motor Europe engineers needed to reconfigure the fuel cell system to fit in the small space allotted.

To get fresh water and air needed for the fuel cells to generate electricity, Energy Observer used other key onboard components. Fresh water was provided through a reverse-osmosis desalination system. An electrolyzer produced pure hydrogen from the fresh water using electrolysis, based on electricity provided by the other renewable energy sources, including solar and wind. For the pure air needed to power the fuel cell, they needed a filter as well.

“They made sure the space was pressurized,” Vercauteren said. “The unit needs air to operate. Air comes through a desalination filter. The salt is separated from the air and filtered after that. Then the module can breathe.”

All energy sources collectively worked together to make all of the Energy Observer’s systems operate at any given time. Aside from the solar energy provided by the panels (top), the battery and hydrogen storage (bottom) could be used at any given time, especially in instances such as nighttime when solar power isn’t available.

Toyota’s fuel cells worked in tandem with the Energy Observer’s other energy sources. The produced hydrogen is stored in pressurized tanks during the daytime when there is excess electricity from solar and wind. According to Energy Observer’s website , the double storage of batteries and hydrogen complement each other. The batteries provide short term immediate power, while the hydrogen provides long-term autonomy. At night or in poor weather conditions, the hydrogen could feed the fuel cells to provide the electricity needed to operate the vessel.

Once the system installation and testing were complete, Energy Observer, equipped with the Toyota fuel cell stack, set off again in February 2020 to continue its mission and circle the globe – more than once!

After 7 years and 68,000 nautical miles of adventure, Energy Observer made it back to its home port in Saint-Malo, France.

MISSION ACCOMPLISHED Energy Observer recently made it back to its home port in Saint-Malo, France, after sailing for seven years, and a total of 68,000 nautical miles . The floating energy lab is anchored in Paris for the summer. The Energy Observer team will continue its work there, providing opportunities to share their experiences by talking about the lessons they learned from circumnavigating the world with hydrogen, solar and wind power with the expected crowds.

Through its voyages, Energy Observer demonstrated the immense advantage that hydrogen can have over batteries, especially in applications where weight is a factor. The on-board lithium-ion battery set weights 1,400-kg (approx. 3,085 lbs.) for 112-kWh of electricity, while the hydrogen storage and fuel cell together weigh a total of 1,700-kg (approx. 3,745 lbs.) for 1,000-kWh. Translated, this means that 1-kWh weighs 12.5-kg when stored in batteries vs only 1.7-kg when stored as hydrogen. In other words, for equal weight, the hydrogen storage contains 7.35 times more power than the on-board lithium-ion batteries, a considerable advantage for mobility, especially in a maritime application.

Based on their experience with this and other applications, both Toyota and Energy Observer agree that fuel cell technology should be applied to help make environmental progress in places that makes sense across society, since it is a proven way to help reduce carbon dioxide emissions that contribute to climate change.

“When I joined Energy Observer, I was curious to know how those high technologies would age at sea,” said Beatrice Cordiano, a scientist and crew member. “I was surprised to see after seven years of the project how well those technologies worked as they faced challenges across the seas all around the world.”

Fuel cells weren’t the only technology being tested in the harsh ocean-going conditions. Solar panels cover almost the entire top deck of Energy Observer.

Energy Observer had set out on a mission to prove that solar, wind and hydrogen could power an ocean-going vessel in a harsh environment – and it worked. The boat, covered in solar panels, was also a testing platform for unique high-tech sail, called Oceanwings, which are now being adopted by numerous long-distance ships.

Now that Energy Observer has proven the technologies can stand up to the rigors of open-ocean travel, the team is setting its sights on larger ambitions. They recently announced plans for Energy Observer 2, what they claim as the world’s first cargo ship powered by liquid hydrogen set to launch in 2029. The plans call for a vessel 160 meters long weighing 1,100 metric tons. Its goal is to operate for 25 years, hauling containers along the Atlantic on 14-day, 1,600-mile cycles. It would demonstrate a solution for the U.N. International Maritime Organization’s goal of halving greenhouse-gas emissions from ocean-faring cargo ships by 2050. These ships currently consume an estimated 250 million to 300 million tons of diesel-based fuel a year, with an annual 1.1 billion tons of CO2 emissions.

Toyota remains in discussions with Energy Observer on future projects, but the collaboration thus far has proven that fuel cell technology has untapped potential in maritime applications. Toyota continues to have discussions with other maritime operators about hydrogen ocean vessels and will continue to explore ways in which fuel cell technology can support carbon emission reduction in various industries.

“Toyota is about much more than cars now,” Vercauteren said. “Hydrogen fits very well into our mobility mission. It allows us to diversify into many different low-carbon applications.”

– Story by Jeff Plungis

Originally published August 27, 2024

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