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International Moth Australian Championship 2024

The international moth australian open championship will be held at the royal yacht club of tasmania tue 9 to sun 14 january 2024..

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Club Of the Year 2022 Club of the Year 2020

In Summary:

HIGH-PERFORMANCE FOILING MOTH

High-performance foiling single-handed boat with camber-induced foil sail, foils on rudder and centerboard and hiking wings on a very narrow hull. It’s an amazing open design but with major suppliers supporting most of the fleet in iterations of “one design.”

Age & Weight Range For The Moth Class:

Typically sailed from 15 up with an ideal weight between 75-85kg but suitable for training above and below that weight.

About the Moth Class

The International Moth is one the most popular classes in the world today, with the boat’s streamlined design offering unprecedented thrills for sailors and spectators alike. Unlike many classes, the Moth has an open design allowing for modification and innovation by enterprising sailors.

It’s this evolution that has seen the Moth class evolve into a state-of-the-art foiling boat, flying at high speed above the water. As a dynamic open-design class, the technology used in today’s world-class Moths can be traced back to a few key innovations over the course of the 1900s. 

In 2019, history came full circle when Mounts Bay Sailing Club was chosen to host the International Moth Class World Championships. Competitors from all over the world united for a heated battle of wills and waves on the very same waters where hydrofoils were first used to success.

Features & Benefits of the Foiling Moth

As a development class, the design and features of the popular Moth has evolved over nearly a decade of competitive sailing. The original 1930s moth was a far cry from today’s hydroplaning models, being a heavy, narrow scow or a blunt nosed skiff.

These original scow moths weighed approximately 50 kg, in comparison to the ultra-fast foiling moths in today’s competition boasting less than 10kg of hull weight. Wings were later added to the Moth boat for greater speed and control. Former Western Australian Premier Richard Court was the first to use the aluminium and mesh wings on his 18ft skiff yachts, a modification that was quickly adopted worldwide.

In the year 2000, local boat builder Brett Burvill revolutionised the class once again, adding hydrofoils to his moth ‘Windrush’ for greater control at racing speed. Brett’s innovation quickly took off and revolutionised dinghy sailing once again, a change that reverberated across international sailing. These lifting hydrofoils on the daggerboard and rudder of the International Moth elevate the entire hull above the water to minimise drag, allowing for unprecedented speed and agility.

Development class

Construction:, carbon fiber or fiberglass, row 2, content 1, row 3, content 1.

Racing in the Foiling Moth

The foiling technology first seen at this Mounts Bay event has gone on to transform world-class sailing events, including the Americas Cup and Olympic class racing.

The International Moth is considered to be the fastest sailing dinghy, reaching speeds of up to 66.5 km/h.

Moth Class Events in WA & Interstate

Upcoming International Moth sailing events:

National Moth class events

Moth Class Website & Organisations:

International Moth Class Association of Australia

International Moth Class Association of Australia (Facebook)

International Moth Class Association

Take The First Step To Getting Out On The Water

Moth fleet in perth – mounts bay sailing club.

At Mounts Bay Sailing Club, we welcome new members to join our Moth Fleet, whether that’s sailing your Moth class boat in our family-friendly Twilight Sailing or weekend racing events or participating in any of our training programs.

Mounts Bay Sailing Club had the honour of hosting the 2019 World Championships, awarded by the International Moth Class Association of Australia (IMCAA). More than 120 International Moth class boats hit the water for a heated competition, crowning the Australian Moth champion as well as our international victors.

Interested in sailing a Moth class dinghy in Perth? Get in touch with MBSC’s sailing development officer to find out how we can get you out on the Swan River as part of our Moth Fleet.

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Class Profile: International Moth

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Engineering:Moth (dinghy)

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The Moth is a small development class of sailing dinghy. Originally a small, fast home-built sailing boat designed to plane , since 2000 it has become an expensive and largely commercially produced boat designed to hydroplane on foils though many are still built at home, typically at much lower cost.

The pre-hydrofoil design Moths are still sailed and raced, but are far slower than their foiled counterparts.

• 2.1 Beginnings
• 2.2 Early growth
• 2.3 International Moth Class
• 2.4 Rebirth
• 3 Moth firsts
• 4.1 National Moth Boat Association (NMBA) Championship 1933-1934
• 4.2 International Moth Class Association (IMCA) International Championship 1935-1972
• 4.3 Competing for the Antonia Trophy from 1933-1964 and the Carling Trophy from 1965-present
• 4.4 International Moth Class Association (IMCA) World Championship 1973-present
• 6 References
• 7 External links

There have been several types of Moth since the first use of the class name in the 1920s:

• The Classic Moth, a traditional dinghy with tighter design restrictions
• The British Moth , designed in 1932 and revived in 2004
• The Restricted Moth of the 1960s and 70s, with few design restrictions to allow for class development (International Moth in Australia and New Zealand)
• The Europa Moth, which became the Olympic Europe dinghy
• The New Zealand Mark 2 scow Moth, abundant in the 1970s
• The International Moth, a fast sailing hydrofoil dinghy with few design restrictions.

The current International Moth is a result of merging two separate but similar historical developments. The first occurred in Australia in 1928 when Len Morris built a cat rigged (single sail) flat bottomed scow (horizontal bow rather than the "normal" vertical bow) to sail on Andersons' Inlet at Inverloch, a seaside resort 130km from Melbourne . The scow was hard chined , 11 feet (3.4 m) long, with a single 7.4 square metres (80 sq ft) mainsail. The craft was named "Olive" after his wife. The construction was timber with an internal construction somewhat like Hargreave's box kite. "Olive's" performance was so outstanding, that a similar boat "Whoopee" was built. Len Morris then sold "Olive", and built another boat called "Flutterby", and with those three boats, the Inverloch Yacht Club was formed. Restrictions for the class known as the Inverloch Eleven Footer class were then drawn up, with the distinguishing characteristic that of being not a one-design boat but rather that of a boat permitting development within the set of design parameters.

At much the same time, 1929 in fact, halfway around the world another development class, the American Moth Boat was started by Captain Joel Van Sant and Ernest J. Sanders [1] of Elizabeth City, North Carolina [2] with the boat “Jumping Juniper” built of Atlantic White Cedar from the Great Dismal Swamp. The major difference between the Australian and American boats early on was that the American boat used only 72 square feet (6.7 m 2 ) of sail on a somewhat shorter mast. The US development class was formally organized in 1932 as the "National Moth Boat Association" and in 1935, due to increasing overseas interest, changed its name to the "International Moth Class Association" or IMCA.

In 1933, an American magazine, The Rudder, published an article dealing with the Moth Boat scene in the US. The Australians noted the similarities between the two groups of boats and intuitively realized that the name "Moth Boat" rolled more easily from the tongue than "Inverlock Eleven Footer Class", and changed the name of their class to Moth. The Australians also noted the differences, particularly in sail plan between the two boats, but since this was in the middle of the great depression, and the two groups were more than 20000 kilometres apart, no attempt was made to reconcile these differences. Thus two large Moth classes developed separately for over 30 years.

Early growth

The British Moth Class dates to the early 1930s. The class was restricted to a particular hull shape of a 1930s Vintage American Moth Boat, and is thus a one-design boat, not a development class which allows experimental development with shapes and materials.

The Victorian Moth Class Association was formed in Australia in 1936. After WWII, the NSW Moth Class Sailing Association was formed, with foundation members coming from Seaforth Moth Club and Woolahra Sailing Club. all other Australian states formed Moth Associations between 1956 and 1961. The Australian Yachting Federation (AYF) recognized the Australian Moth class as a national class in 1962, the first small boat class in Australia to be granted national status. Australian Moths were using pre-bent and wing masts in the 1950s. In the 1960s, Australian Moth sailors campaigned for rules changes that would permit the Australian Moths to compete in the IMCA's "World Championships". [ citation needed ]

European interest increased after the second world war. The European Moth clubs subscribed, more or less, to the US class rules. One European Moth design from the early 1960s, the "Europa Moth", broke away from the IMCA and formed the one-design Europe dinghy class. It was adopted as the woman's single-hander used in the Olympic games from 1992 to 2004. [ citation needed ]

International Moth Class

In 1971 the US-based IMCA completed a phase-in of new rules which attempted a "marriage" of the IMCA and the Australian Moth. This amalgamation process had started at the annual IMCA meeting in 1965. New rules embraced the larger, more powerful high aspect, loose footed, fully battened rig of the Australian Moth. The new rules also permitted controversial hiking wings first seen on Moths from Switzerland. Finally, guided by the influential UK Moth sailor and WW2 war hero, Major Tony Hibbert, the rule change abolished the US centralized organization of the class in favor of an independent world body with equal-partner national associations. Each national association elected its own officers and world body representatives. The culmination of these changes was the recognition in 1972 of the IMCA by the International Yacht Racing Union (the forerunner of today's World Sailing) bound by the agreed upon new restrictions of the class (with metric measurement conversions) operating today. The moth class association that had originated in the US was now truly an international organization.

Being a development class, the Moth has evolved from a hull in the 1930s that could best be described as a heavy, narrow scow or a blunt nosed skiff, (weighing about 50 kg) to today's remarkable foilers with hull weights of under 10 kg. Designs have run the gamut from wide skiffs without wings, to lightweight scows, to wedge-shaped hulls characterized with narrow waterlines and hiking wings out to the maximum permitted beam. Likewise, the sail plan has evolved from cotton sails on wooden spars, through the fully battened Dacron sails on aluminum spars, to the windsurfer inspired sleeved film sails on carbon masts seen today.

In New Zealand the class reached its maximum popularity in the late 1960s and early 70s. The NZ Moth was standardized as a 41kg flat bottom scow type known as the Mk2 using an alloy spars and a Dacron sail. The measured sail area was nominally 7.4 square metres but the actual area grew to about 8.2 square metres by 1970. Many hundreds were home made by amateurs. In addition there were a smaller number of International Moths of both scow and skiff type. Hulls were noticeably lighter -down to 23kgs for skiffs using plywood by 1970. The international yacht designer Bruce Farr built Moths to his own design in the 1967-1971 period when still a young school boy.

In the United States in the late 1970s participation in the International Moth class died and the class growth and interest moved to Europe and Australia. After ten years of little Moth activity in the US, several sailors started looking for old Moth Boats with the original US rig to restore and race. A newsletter was started to aid communication between like-minded Mothists. Racing of "Classic Moths" resumed in 1989 and in 1990 a new club was formed to govern racing and construction of Classic Moths. This club, the Classic Moth Boat Association or CMBA is the current governing body for the original US type of Moth Boat. The intent of the CMBA is to revive the original US version of the boat and update the rules so that development is permitted without allowing the boats to become too freakish. The IMCA rules from 1965, the final year prior to the phase-in of the Australian rig and wings were consulted as a starting point for reviving the US Moth. Those rules have been revised where necessary. Interest in Classic Moths has grown internationally, with new activity in Europe, primarily France.

Moth firsts

The International Moth has fostered a number of achievements. In 1966–67, The King of Siam was involved in the building of three Moths and sailed them on the pond at Chitrlada Palace. The King raced for almost 20 years on his second moth called 'Super Mod' until his design and construction efforts were cut short by the 'press of royal duties'. [3] In 1957 Patricia Duane became the first woman to win the Moth World Championship in her Cates-Florida design. [ citation needed ] In 1968 Marie Claude Fauroux became the first woman skipper to win a World dinghy racing title from an IYRU sanctioned international class, in her Duflos-designed moth. [ citation needed ] The International Moth was selected [ when? ] as an official training class for the Japanese Olympic sailing team, to hone their balance skills. [ citation needed ]

Since 2000 International Moths have begun using lifting hydrofoils on the daggerboard and rudder, which lift the entire hull and skipper above the water surface, dramatically reducing drag and increasing speed. The top speed achieved as of 2018 is 36.5 knots, the highest 10 second average of 35.9 knots [4] (66.5 km/h) was recorded on 14 May 2014. This high speed is reflected in the International Moth's RYA Portsmouth Yardstick of 570, the fastest ( (As of 2016) ) of any sailing dinghy or multihull. [5]

National Moth Boat Association (NMBA) Championship 1933-1934

International moth class association (imca) international championship 1935-1972, competing for the antonia trophy from 1933-1964 and the carling trophy from 1965-present, international moth class association (imca) world championship 1973-present.

Similar boats

• Skimmer (dinghy)
• ↑ "Fun, local history surround national moth boat race in N.C." . https://www.pilotonline.com/news/article_9a72cd9f-d07a-5f6d-bd90-3a2e4521411a.html .  
• ↑ "Classic Moth Boat Association" . Classic Moth Boat Association . http://www.mothboat.com .  
• ↑ "Olive -" . http://www.moth-sailing.org/olive/ .  
• ↑ Goss, Ned (14 May 2014). "CONFIRMED: 36.6 KNOTS ACCORDING VELOCITEK PROSTART" . Sail Anarchy . http://www.foilingweek.com/blog/2014/05/confirmed-36-6-knots-according-velocitek-prostart/ .  
• ↑ "Portsmouth Number List 2018" . Royal Yachting Association . https://www.rya.org.uk/SiteCollectionDocuments/technical/Web%20Documents/PY%20Documentation/Historic_PN_List%20-%202018.pdf .  

External links

• Classic Moth Boat Association
• International Moth Sailing

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MACH2 Essentials

All you need to know about the Moth class and Mach2 in particular. All the essential information regarding the boat, it's history, evolution of foiling, the designer, the sailmaker and the boat builder. There's even an introductory video and a few testimonials. Enjoy!

The Designer

Andrew 'AMAC' McDougall first became involved with the Moth class when he built his first Moth at the age of 15 in 1970.

Need some parts for your Mach2? We have a full compliment of sails, spas, foils and Mach2 spares available online.

Speed Demons

36.6 ned goss.

Is this a world record speed for a dinghy? Ned Goss in a 18-25 knot Charleston sea breeze hit a peak speed of 36.5 knots, with a 10 sec average of 35.9 knots in his MACH2. Goss’s Velocitek files were verified by Bora Gulari & Velocitek founder Alec Stewart. Take that!

30.2 Josh McKnight

Following his win at Lake Garda, 2012 World Moth Champion, Josh McKnight then set an outstanding top speed and ten second average on his Mach2. It goes to show the Mach2 / KA Sail is a killer combination!

31.5 Scott Babbage

Scott Babbage set this speed sailing his MACH2 on Sydney Harbour whilst training with Josh McKnight. Any top speed that's above 30 knots is well worth a mention, but to have a ten second average that is also above 30 knots, wow!

31.4 Hiroki Goto

Sailing at a lake in Japan near Mount Fuji, Hiroki Goto, set a very impressive top speed of 31.0 knots, only to surpassed his on record the following day with a top speed of 31.4 knots and a ten second average of 28.4 knots.

MACH2.6 Is Here

This is the fifth major upgrade in the illustrious life of the Mach2 Moth. Already it's proving to be dominant. For the complete list of upgrades and features, hit the link below

Testimonials

We take a great deal of pleasure designing, building and supporting the best foiling Moth in the world. And nothing gives us greater pleasure than the positive feedback we have received from MACH2 owners over the past 10 years. Here's a few owner testimonials........

Thanks for Visiting the MACH 2 Website

Before you go, sign up to keep up to date with all the latest MACH2 developments.

Hydrofoil sailing boats in the moth class sailing world championships changed the America's Cup forever

When Brett Burvill won two races at the moth class sailing world championships in Perth almost 20 years ago, he could not have known how a small change he made to his boat would reverberate around the world.

"He finished 10th [overall], which is pretty good for a crazy new development, but he won at least two of the races I think," recalled friend and fellow boat builder John Ilett.

"They were really spectacular, because he would not go very well at the first part of the race, and then the next part he would pass 20 boats, and then another 20 boats.

"He was just twice the speed."

Next week, more than 100 competitors will return to the Mounts Bay Sailing Club for the 2019 World Championships, two decades after Burvill unveiled his revolutionary innovation.

He had attached a hydrofoil to his boat, which provided lift, reduced drag and dramatically increased his speed.

It also set in motion innovations which made their way to the biggest race in global yachting.

Superfast hydrofoil caused a stir

Burvill wasn't the first person to put hydrofoils on a boat, but he was the first to successfully race them.

"There were ones done in the 1970s, with moths, and ones in the 1990s, but these were never sort of proven in racing," said Ilett, who was an early adopter of hydrofoils.

"People experimented with it but until you actually sail around a course and win a race or win a regatta, then that's when the concepts are proven and adopted.

"I think it was just the inspiration of other crazy boats flying around, because it had been done to other craft but it had not been done in the moth class.

"The moth class is open to any new development, so if you can make them go faster, then we gave it a try."

The attachment of foils to the moth boats brought plenty of resistance, with some competitors concerned the increased speed and difficulty of control would kill the class.

"There was a lot of backlash to it in the beginning," Ilett said.

"The class wanted to ban it, some people wanting to ban it, people walking away from the class and saying I'm never coming back, so there was a lot of fuss about it."

So how do hydrofoils actually work?

Hydrofoils are not a new invention, with their use first recorded 150 years ago when a British patent was granted to Frenchman Emmanuel Denis Farcot.

He claimed that adapting to the sides and bottom of a vessel a series of inclined planes or wedge-formed pieces would have the affect of lifting it in the water and reducing the drag as it went forward.

Inventor Alexander Graham Bell, who is best known for the telephone, also built a foiled boat called a HD-4, which set a marine speed record of 114 kilometres per hour in 1919.

Since then, the technology has been used in military and passenger capabilities, but there prevalence has declined over time, with the foils susceptible to impact and also posing a risk to marine life.

Hydrofoils work in essentially the same way as aeroplane wings.

As the boat moves forward, the hydrofoil travels through the water, but the water that travels over the top does so at a faster speed.

The faster the water travels, the lower the pressure, resulting in an area of low pressure above the foil and high pressure below the foil.

The difference in pressure creates lift, allowing the boat to rise out of the water.

With the hull of the boat out of the water, drag is reduced, and vessels can reach higher speeds.

Making it to the America's Cup

The successful application of hydrofoils in the moth class demonstrated their value to racing and saw them adopted across numerous sailing classes.

But it was their use in arguably the world's most prestigious race that completed their emergence in mainstream racing.

"It's pretty cool," Ilett reflected.

"I think it probably seemed inevitable. I think I'm right that in the early days of the America's Cup they did try to stop the hydrofoil developments, but like the America's Cup do, they found a way around it."

Those changes were implemented in 2013, when America's Team Oracle completed a remarkable 1-8 comeback to claim the event 9-8 over Team New Zealand, with the yachts reaching speeds of about 80kph.

The adoption of the hydrofoil in the Cup has a benefit for those who still race the moths, with successful skippers often hired to compete in the big race.

"It's put a lot of America's Cup sailors into the moths class because it's easier to get the guys out on one of of these more often — for training, for learning and getting a feel for flying," Ilett said.

"Even the guys on the America's Cup boats that don't do particular jobs, they all sail on these boats too."

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INTERNATIONAL MOTH SPEED GUIDE

Moth Dinghy expert Rob Greenhalgh introduces this extraordinary singlehanded foiling dinghy and describes the keys to sailing one fast.

Who sails the foiling Moth Dinghy?

The Moth class is for everyone—it’s so exciting, you don’t need to race it. Club sailors can get a huge buzz out of foiling, going fast around the bay, and learning to foil jibe and tack. They might enjoy it so much they never need to join a race. At the other end of the spectrum, there are sailors who have been in Moth Class for a decade or more and love the challenge of racing this exciting, complex craft. 

Viewed from stern or bow, the foiling moth is a high-speed machine, clearly unlike other sailboats.

What kind of sailors enjoy this challenge?

Moths are development boats, not a strict one-design class, and that’s daunting for some. The technical and evolutionary side of Moth sailing requires a good understanding of how everything works—how the foils interact with the rig setup and how to balance both aspects. Over the last five years, there have been massive speed advancements, which will continue. To be at the top of the game, you have to enjoy the technical side. But you can buy equipment off the shelf and, if you practice and sail well, soon be up to pace. Though more technically oriented sailors often gain an edge for a while, there are also lots of people who will make changes that don’t help them, so it evens out.

How physical is the sailing?

When you are first getting into it, Moth sailing seems physically hard, but once you’ve done it a while, it’s not too bad. On a windy day with a lot of capsizing, it gets pretty tiring. But it’s a light boat, and the loads are not high. Anyone can do it if you can move quickly at times. There are plenty of Moth sailors in their 60s.

New boats or used, which are better?

My advice for the first-time or second-time buyer is to look for a good second-hand boat that you know will fly. This saves you a lot of effort, because even experienced Moth sailors need a few months to work up a new boat. Sure, it’s always a worry that you might not be getting good enough kit with a used boat, but in my experience, any modern Moth can be made fast. If you want to buy new, a standard boat from either of the two main builders—Exocet by Maguire Boats, or Mach 2 by MacDougall McConaghy—will quick enough for top 5. You can also have a look at the new Bieker Moth by LSF Composites.

The Moth is a development class. What’s happening lately?

The Vi-8 DS 3Di (on top) and Vi-8 LA 3DI feature the same sail area. The LA has more power in lighter winds to foil more quickly; the DS has less drag at high speeds.

What sails do you recommend?

8LA-3Di provides extra power to get on foil.

Which sails do you use?

The decksweeper (Vi-8 DS 3Di) creates an endplate and lowers aero-drag. It is slightly faster once foiling.

How does foil choice affect sail choice?

Moths have two foils, a larger foil for lighter winds and a smaller foil for stronger, and that’s a choice you have to make on the beach. In my case, if I expect to be on my foils all day, I’ll choose the smaller foil and the deck-sweeper sail. If the winds are lighter or less reliable, I will often choose the big foil and the LA sail. And if I expect light air to start but a building breeze all day, I’ll likely choose the big foil with the deck-sweeper sail.

Tuning the Moth Dinghy

What are the keys to tuning a moth.

Generally speaking, you should set up your boat to carry as much rake as possible. How much is that? You’ll know it’s too much if you can’t get under the boom in tacks and jibes. This is not something you do underway, and if the boom is making boat handling more difficult, make the rig more upright until that smooths out.

What other key adjustments do you make before launching a Moth?

Batten tension is one. For Batten 1 (the top batten) down to Batten 5, just take the creases out of the batten pockets—don’t over-tighten them. For Batten 6, remove the crease and then add two more turns by twisting the batten key two full revolutions in a clockwise direction. For Batten 7, take the creases out and add three turns. The outhaul is also non-adjustable underway. Rig the boat ashore with the outhaul loose. Pull on max vang and max cunningham, and then pull the outhaul tight. This will give you a good all round setting.

What other settings can you recommend?

Here some of the numbers from my boat, but don’t worry if your measurements are different. Comparing measurements boat to boat may not matter at all. The important thing is to start recording them and experimenting.

• Front Prodder 340 (adjustable +/-50mm)
• Side Arm 410mm
• Deflection 220mm
• Shroud Base 1500mm
• Mast Length 5100mm (excluding plastic plugs top and bottom)
• Back of mast to clew ring 2340mm

From mast length to shroud base, it's important to record all of your boat and rig measurements. You will change them over time.

How do you set up your foils, actuator wand, and gearing?

Sailing in rougher water requires faster gearing between your actuator and main foils. Foil gearing is a critical control for waves; make sure it can be adjusted for rough waters. To get through waves you need faster gearing. You’ll also change foil size depending on the wind forecast. I have two sets of main foils and use the smaller one on windier days. However, if the wind is light for the first race and predicted to build, I’ll go with the larger foil because the speed penalty of not being able to fly with other boats can trumps all other considerations.

Upwind Moth Sailing

What is most important when sailing upwind.

On any point of sail, the vang and cunningham are powerful controls, and need constant adjustment for different conditions. The goal is to generate power for low-riding and to get up on the foils, and then flatten the sail as the wind builds. One of the challenges of the Moth is it has a maximum 8.25 square meters of sail area, and upwind in most conditions, that’s more sail than you need. Downwind, you have the opposite problem; your speed reduces the apparent wind so much, you’re always starved for power.

What is low-riding mode and how do you sail fast in light winds?

In general you don’t race in winds when you can’t foil, but it may happen that the wind lightens up substantially during a race. Sailing in low-riding mode is an art in itself, something like balancing in a canoe because the hull is so narrow. I always recommend practicing sailing that way.

What does it take to fly a Moth?

Heel the Moth to windward to keep the boat more stable and reduce leeway.

Why do you tip the Moth to windward when flying?

We sail with the rig always tipped to windward because it keeps the boat more stable and reduces leeway on the main foil. Use very subtle steering and trimming of the main.

How do you trim the Moth sailing upwind?

Correct trim is the absolute key to good boatspeed. It’s very easy to over-sheet and stall the front of the mainsail. Always have the inside tell tales lifting. A common mistake is sailing under-powered and over-trimmed. As the wind increases, flatten the main by tightening vang and cunningham to accommodate the higher apparent wind speeds.

How do you adjust sail trim for gusty winds?

You need your rig set-up to be user friendly. That means having enough vang and cunningham to straighten the sail. If twisted, the center of effort can move up and down the sail. It takes a certain level of confidence to get to the point where you can let go of the mainsheet to tighten the kicker and cunningham.

Downwind Moth Sailing

What is the key to good moth speed downwind.

Sailing downwind, be sure to maintain a big entry angle in the lower part of the sail and avoid over-trimming.

What is your focus when trimming downwind?

I focus closely on my lower tell tales, keeping them flying 100 percent and making sure I ease enough to keep the sail ‘hooked up’ with airflow attached. I look for a nice big entry angle on the bottom part of the sail and clean up any horizontal creases by subtly tightening the cunningham. From there, it’s a matter of very subtle trim and steering. If in doubt, ease the sheet and be sure you have good flow going around the front of the sail. If you run into a light patch, just head up to keep the flow going on the main. If needed, power up the main even more. Get the gearing really slow on your foils to minimize drag. The boat will go faster and apparent wind will increase, moving the wind forward and letting you trim harder. Especially when it’s a bit lighter downwind, be sure to pre-empt a drop in apparent wind by easing main and bringing the bow up!

Moth Tacking, Jibing And Gear Changing

How do you foil jibe a moth.

When foil tacking or jibing, you need to flatten the boat. For jibing, bank into the turn to leeward. You’ll turn the boat more aggressively when your body is ready to move across to the new wing.

How do you foil tack a Moth?

When tacking you have to move quickly, bringing the boat relatively flat once head to wind. Start luffing slowly, taking the edge off your speed; make sure the boat is flat when head to wind. As my body moves across the middle to the new wing, I’ll increase the rate of turn, steering quite aggressively through the eye of wind, but my body has to be ready to cross the boat and receive the power on the new tack. You need to come out tipped to windward. Here’s how I break it down:

• Ten seconds before tacking, consider slowing the boat slightly and sailing slightly higher.
• Plan for a slow luff head to wind, followed by a faster turn rate once confident that crew weight can be positioned correctly.
• Heel to windward before the tack but flatten the boat once head to wind. Move your weight inboard. It is important here to sheet the mainsheet on centerline so that it is not over the leeward wing when you pass underneath.
• As you move across the middle of the boat, pass the tiller extension around the back and into a position halfway along the leeward wing.
• When you are confident you can move to the new side, increase the rate of turn, landing on a wider than close-hauled course.
• There are a lot of G-forces during this period, so expected to get ejected a few times!
• Don’t try to piece the whole tack together immediately. Practice the first phase of luffing head to wind, getting your weight to center, and switching the tiller extension across.
• Remember to ease mainsheet out of the tack and have your hands positioned so that the sheet can be eased quickly. The sheet is more important than the tiller on exit.
• I set my mast rake to allow 70 to 75cm between the boom and the deck where I cross the boat. Tacking is important, so make sure you have room under the boom! For tacking practice, I recommend having the rig more upright.
• Don’t adjust any control lines right before or after tacks, unless it is very light and foiling is marginal.

Name 5 key gear changes in a Moth

• To foil early in light air, power up by having the vang and cunningham as loose as possible. However, it is easy to over-deepen the front of the sail, requiring further bear-away to get good flow on the sail. Don’t overdo it.
• Downwind always requires a deeper sail shape than upwind, regardless of wind speed.
• Once foiling, immediately pull on vang to stabilize the sail and cunningham to clean the creases. Even though the wind is light, we are quickly doing 14/15kts. The AWS is high so we need to change sail shape to achieve good speeds.
• As the breeze builds, constantly increase vang and cunningham loads to achieve the desired sail shapes. Max vang should be achieved in 15 knots and max cunningham in 18 knots.
• The Moth gets overpowered quickly, and from 18 knots upwards a softer tip or different sail is required. North’s LA and DS designs have a slight variation in the luff rounds to cover the range, with the DS being aimed at 14 knots true wind speed. For lighter sailors, a softer-tip allows the mast to bend earlier and depower the sail.

How do you start a race in a Moth?

Starts are a bit chaotic. Even for long-time racers, a Moth start will be a new experience. People get up on their foils with about 25 seconds to go and do a big turn-up at about 3 seconds, crossing the lining at 20 knots. A key thing when you’re on your foils is to have the ability to slow down while maintaining control. You need to practice that. Getting to the pin too soon is dodgy, especially with boats starting on port tack.

Why do so many Moths start on port tack?

Moths travel at 15 to 18 knots upwind, so tacking is a very costly part of an upwind leg. Reducing the number of tacks during a beat is very efficient, although this depends somewhat on how well you tack and how confident you are in making your tacks.

How many ways can you capsize a Moth?

You will capsize a Moth every possible way when learning. But I can sail for days now without capsizing, unless it is windy and choppy. The key to recovering quickly is to get on the daggerboard and do a dry capsize, climbing back over the wing. Sometimes that’s hard to do, especially when you pitchpole and find yourself 20 meters out in front of that boat.

What is the most common boat-handling mistake in a Moth?

Capsizing! Foil tacking, in particular, is very difficult. A common mistake is trying to foil tack when it’s breezy. Drag is so high that as you go through head to wind, everything slows down and it’s easy to capsize. You may be better off planning to do a touch-and-go tack. 

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From www.moth.asn.au - International Moth Class Association of Australia

The International Moth is an eleven foot long, high performance, single handed racing dinghy. We are proud to be one of the few development classes left in the world and have very few design rules including no weight limit. We encourage innovation just as much as we encourage sailing skill. We welcome home boat building and wacky designs, and almost importantly, we welcome unconventional people with open arms. This offical Australian Moth web site has all the latest National information that you need to start Mothing right now.

Length overall     3.355 m

Beam     2.250 m

Max. luff length     5.185 m

Max. mast length     6.250 m

Hull weight     Unrestricted, general weight range 10-20kgs

Rigged Weight     as little as 26kgs

Sail area     8m

Restrictions     Multihulls, trapezes, moveable seats and sailboards are prohibited.

Optimum skipper weight     60-80kgs

Advertising     Category C (unrestricted)

Trevor Riddell  - Boat Builder and Moth Creator

Afloat 2010

Being a retired builder of wooden boats and a keen yachty of 1931 vintage, l find much to interest me in Afloat.

l am saddened to learn of the passing of so many of my old seafaring mates  such as Arthur Byrne whom we sailed against in Norm Brooker's Seawind . We had quite a few great racing battles against his Salacia.

Recently my old cobber, Trevor Riddell, has also sailed off into that harbour in the sky.

I started my apprenticeship with Trevor's father, Andy and Trev's brothers, George and Bob. Trevor was very involved in the AIF and was deeply affected by the war. He found it extremely hard to concentrate. Although starting his apprenticeship two years before the war, he did not complete it till a few years afterwards.

I started my five year course in 1947 and, with the Riddell brothers, built some fine yachts. One notable memory is of the two yachts designed by the late Alan Payne (another good friend) and also the Laurent Giles 10 metre. Even for F.J. Palmer. This boat scored Line Honours in the 1955

Sydney-Hobart Race. My last job with the Riddells was building a Dragon for Norm Booth, the well-known Sydney car dealer.

Vic Robinson lived next door to the Riddell family in Seaforth bay. Upon coming across an article in an American magazine, Vic was very keen to build a Moth Class sailing dinghy. His enthusiasm soon had Trevor and me building one each, too. Before we knew it, we had started a new sailing class on Sydney Harbour!

Our sail numbers were 146, 147 and 148. With fast-growing interest from other clubs the sail numbers climbed to over 2,000 in no time at all.

We constructed a clubhouse in Seaforth bay and had a rapidly growing competitive fleet. Many a talented yachty graduated from these little craft, including another of my deceased mates, Poddy O'Donnell, forehead hand aboard the America's Cup challenger Gretel.

Dave Linton,

Perth, Tasmania

Middle Harbour Regatta 1959

The following is an excerpt from the Middle Harbour Regatta Program 1959

MOTH CLASS SAILING

The Seaforth Moth Sailing Club was the first Moth Club in New South Wales and held its first race at Seaforth Bay in September 1952 with six starters.

Since then the Club has steadily grown and now has its own Clubhouse at Seaforth that houses twenty-two Moths.

The season is from early September through to late April each year and the standard of sailing is always high.

This season members of the Club already hold the Australian, State, Lane Cove and Pittwater Championships.

Balmoral Moth Sailing Club, not as old as Seaforth, has over sixty Moths registered, the biggest fleet in Australia. With their Clubhouse situated at an ideal location on Balmoral Beach, it is the centre of the social functions connected with the Moth Class.

The class is widely represented throughout the world and is subject to the following restrictions: .

Length: No more than 11ft, no less than 10ft.

Mast: No higher than 20ft. 6in. above the deck. '

Sail: No larger than 80 square feet.

These measurements allow scope for innovations and experiments in design. Each boat, mast and sail must be measured before competing in Club or inter-Club races and is then registered with the New South Wales Moth Class Sailing Association who allot a number. This number is stencilled on the sail together with the Moth insignia for easy recognition.

In addition to races run weekly by the various clubs on their own courses, inter-Club and Association events are held on courses from Pittwater to Broken Bay, the majority on Sydney Harbour and its estuaries.

Hulls are normally of plywood construction and weight varies from 65lbs. to 130lbs. Boats can be easily carried by two youngsters and transported on top of cars or on light trailers. Moths are particularly safe craft for beginners, the majority being Watertight and easily righted when capsized. Juniors of ten years of age with a senior to handle the sheet rope have no difficulty in sailing. Having only one sail they can be handled quite competently by one person in winds in excess of 30 m.p.h. Ages of those sailing boats regularly range from 12 to 45 years.

Moths are becoming increasingly popular and offer a method of teaching youngsters from the age of 10 or 11 years to sail, developing their initiative and enabling a considerable number of people to enjoy the advantages of the open air and the exhilaration of controlling a fast-moving boat on our beautiful coastal waters.

The illustration is of the Australian champion, John Henderson, of Seaforth Club, sailing his boat Nil Desperandum, Number 353.

Swift Hydrofoils

Damic Design specialises in design and manufacturing of Moths and Hydrofoils for the International Moth Class. While Moth sailing is our passion, our main objective is to offer the fastest, most developed and best built boats and foils on the market.

Our involvement in the class started in 2004, exposing us to the world of Moth hydrofoiling technology since the early days. The initial period was quite experimental, but also fun and educational as it allowed us to learn and develop our design ideas. We made a lot of foils in this phase with the most successful being the Macita that won the 2013 World Championship. While this foil is not on offer anymore, it certainly paved the way for the foils we make today.

In particular, the Swift range which consists of a number of sizes, each with different lift and control characteristics designed to ensure optimal performance over a wide range of sailing conditions. This range has now grown to include: Two rudders hydrofoils (Small and Medium), three mainfoils (Super Small, Small and Large) and our super thin HM carbon verticals.

The Swift Hydrofoil range is a refined product line with the foils now in their 3rd generation of improvements. We are constantly looking to make gains that we first test, and then bring into production.

What this means for you is that every product in the range is on trend and offers performance improvements for your boat without the need to upgrade the entire platform. While this range is sold with our Swift Moths, it is also available to Bieker, Exocet and Mach 2 owners that are looking for a fast upgrade option. Our foils placed 7 out of the top 10 at Perth Worlds, won 2023 NSW and Australian Nationals and also got 2nd in the Waymouth Pre-Worlds regatta. Furthermore, all Damic Design foils are made in Australia and are constructed from solid carbon fibre, from market leading supplier, Toray. While this increases production costs we believe it is warranted as it insures superior quality and perfomance on what we consider as the most important part of the boat. We are also proud to be the only foil manufacturer that is solely focused on foil development and directly involved in design, testing and manufacturing of all of our products. That means that every foil that leaves our workshop has been hand finished by the designer and Moth sailor that truly understands the product and what is required to make it go fast!

Swift Mainfoils

Swift Super Small (v2)

Our latest hydrofoil, specifically designed for light sailors or as a strong wind foil. It features an innovative tip and bulb design that are optimised for reducing drag when going fast.

$3,350 AUD + GST

Swift Small (v3)

The ultimate all round medium wind foil, that has been winning regattas since the initial release. It is known for having great control features with a very wide performance window.

Swift Large (v2)

Excellent high lift foil that can be carried up range thanks to its thin section and very efficient profile. This foil is a proven race winner and a must for heavy sailors or light wind venues.

Swift Rudderfoils

Swift Small Rudder (v1)

The Small rudder is based on the same theory as our Medium. It is a high aspect low drag shape designed to minimise drag and maximise lift offering great glide though ability for ease of foil tacking. Unlike other small rudders, ours still makes foil tacking a breeze while being tiny in size and super fast.

$2,200 AUD + GST

Swift Medium Rudder (v3)

Our Medium rudder is a well proven design that is a result of many years of development. Its short cord makes it very low drag however it generates plenty of lift thanks to its high aspect ratio. This foil will help make your foiling tacks easy and repeatable. $2,200 AUD + GST

Swift Verticals

Swift HM Rudder Vertical (v3)

The v3 is our latest design to date. It further improves on the original v1/v2 designs with changes in the bottom 1/4 of the section. It is designed to be on the absolute limit of the materials to insure the ultimate performance from reduction in drag coefficient. It also includes a number of design features that combat the “all too common” rudder wash out problems. Made from pre/preg solid High Modulus carbon fibre construction, it is thermally stable and ultra stiff.

$4,100 AUD + GST

Swift HM Main Vertical (v1)

This is the thinnest main vertical on the market which offers significant reduction in drag by simply being smaller to reducing skin friction and displacement. Made from solid High Modulus carbon fibre construction, it is thermally stable and ultra stiff. Includes pushrod and bellcrank kit.

$4,500 AUD + GST

AOA Templates

These angle of attack measuring templates, are designed to fit our range of Swift main and rudder hydrofoils. With the help of this device, you will be able to determine the all important foil angle relative to waterline. $45 AUD + GST

Swift Vertical Covers

Tailor made to suit Swift HM Main verticals and HM Rudder Verticals. These premium quality covers are Australian made using quality Dimension Polyant sailcloth. They features marine canvas outer skin and felt lining inside. $120 AUD + GST

Swift Horizontal Covers

Suitable for Swift Super Small, Small and Large horizontal hydrofoils. These premium quality covers are Australian made using quality Dimension Polyant sailcloth. They features marine canvas outer skin, felt lining inside and Velcro closure to protect the trailing edges. $110 AUD + GST

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