The International 505 is a boat of many qualities and is, we believe, the ultimate high performance racing dinghy.

It has the perfect balance of power and control, is free of vices and is well-mannered and forgiving. Crews and helms of combined weights from 23 to 30 stone (146-190 kg or 321-418 pounds) can be internationally competitive, whilst lower or higher combined weights are competitive at club level.

The 505 has a long racing life and good inexpensive boats are available on the second-hand market.

The Class has strict international controls, the result of which is that it has never suffered an overnight obsolescence. There is an unrivaled training organization and strong club fleets around the country, together with a superb open meeting calendar at venues throughout the UK and a range of European cup events.

The Boat

The International 505 is certainly a powerful boat that demands a great deal, physically and mentally, both from helm and crew but, in return, it provides a challenging, exhilarating, breathtaking performance and a balance of power and control that is unique.

Always responsive, a 505 will plane upwind in a force 3, but off-wind? well!, a screaming three-sail reach, with two-thirds of the boat out of the water, but still under control (after a little practice), is an experience difficult to describe and impossible to forget. Some high performance dinghies can behave like real animals, but you will find an International 505 to be remarkably well-mannered and forgiving.

To many the biggest surprise about the Class is the fact that Championship races are won by crews weighing anything between 23 and 30 stone (146-190 kg or 321-418 pounds). A genuine seven stone(45 kg or 100 pound) weight range.

The key is that Class rules enable enough variation in the way that masts are rigged (height of spreaders, hounds, trapeze wires and with various mast sections), that allows power levels to be tailored to individual needs. A range of spinnaker designs and sizes further allows you to complete your desired configuration. However, our rules allow only small tolerances in the hull shape which is as attractive and efficient as it was when John Westell's design genius became a production boat back in 1954.

The International 505 Association's open-minded, but cautious, attitude towards any change that may create over-night obsolescence, of have a serious impact on cost, ensures that this yacht, with its sophisticated construction and build quality, low weight and lasting stiffness, has an incomparably long racing life.

The myth that a 505 is 'shot' after one or two seasons is still believed by some and promoted by others. Suffice to say, the 1988 Worlds, in Sydney Australia, were won by a five year old British built Parker (and a rather good yachter), and when the Dane, Jorgen Schonherr, won the 1990 Worlds, in Kingston Ontario, in his four year old Australian Kyrwood, the American that was pushing him hard, all the way to the last day, was sailing a thirteen (yes 13) year old boat.

The fact is that in a healthy second-hand market, a genuinely competitive, down to weight, stiff 505, can be bought at a very affordable price, and this is the way that most get started.

The Competition

The 505 is a truly International Class, raced in a least eighteen countries, and to represent the UK is an honour which has to be fought for. Leading helms from other Classes quickly find out how difficult this can be but, having raced a 505, most thrive on the challenge and persevere. This makes for the highest level of competition, sailing 'Superstars' like Cudmore, Warden-Owen, Smith, Elvstrom and Pajot (For names more familiar to North American readers, Paul Cayard, Jonathan McKee, Charlie McKee, Carl Buchan, Carol Buchan, Sally Lindsay, Cam Lewis, JB Braun, Rod Johnstone, Gary Knapp, Gary Bodie, John Marshall, Allison Jolly, John Bertrand, Dave Ullman, Neal Fowler, Steve Benjamin) have all spent time in 505's. If anything, the competition to represent your country gets tougher, many believe that this competition is the toughest, and they are probably right.

Many like to combine 'circuit sailing' with racing at their home club and indeed the majority of 505 sailors only sail at 'home'. The Association strongly encourages Club racing and it is the way that most people find out about the Class. If you enjoy handicap racing then you will find that a 505 performs to its handicap right across the wind range.

So, whether you see yourself at the toughest World Championship, screaming off the waves in a Force 5 or 6, or racing around the cans at your Club on a Sunday, in fleet, handicap or pursuit racing, a 505 will be happy to oblige.


At many Clubs, you will find boats tuning up together, this is something that most club fleets are encouraging. Once you have got the feel of things you will find this sort of session most useful.

By the way, everyone (and we mean everyone), does a fair bit of swimming in their early days of 505'ing, but, usually this phase soon passes. Anyone who tries to tell you that they didn't is either being economical with the truth, or they never go sailing in anything over a Force 3. If they are not 505 yachters, or they are standing on the beach having a laugh at your expense, just think of the feeling you will get when you maintain a position ahead of them on the water. Whatever you do, don't worry about taking the occasional 'dip', give yourself time, every 505 yachter has been through the same experience.

Buying Second Hand

What To Look For
Construction techniques are relatively sophisticated. GRP hulls are usually 'cored' with closed cell foam or end grain balsa. Carbon fibre is extensively used by some builders and, to a lesser extent, Kevlar. Resins may be polyester or epoxy. The methods used allow builders to optimize weight distribution and strength.

In the US, three builders, Lindsay, Hamlin, and Waterat, have built fully cored, epoxy hulls, that appear to last indefinitely. The oldest were built in 1977, and if well cared for, are still capable of winning a North American or World Championship. Some of the following discussion is more relevant to not-fully-cored, polyester layup boats.

Lasting stiffness and strength is paramount in the rig tension areas, the forward end of the center board case and, the crews 'landing areas'. Topsides, towards the bow and stern, the foredeck and the aft 2-3 foot of the seat tanks, will often feel quite flimsy compared to a heavier, or wooden, boat. This is because the builder strives to keep weight out of the ends, to reduce the pitching moment. These parts of the hull are not under any significant load and are built to the minimum weight that is both safe and durable, so don't worry about this.

Generally, if the boat has been looked after, a 505 will maintain its rigidity and strength for a very long time and a good second-hand boat is and ideal introduction to the class.

Points to Check
Seat Tank Landing Areas
Helm and crew positions take most of the body impacts. Like the hull floor, these sections of the tanks are usually of cored construction. Any softness can mean that delamination has occurred in the 'shock' areas of that the core is damaged.
Cracked tanks
Cracks where the seat tanks join the floor, or front bulkhead, or around the front tank bulkhead, could compromise the inbuilt buoyancy and may be symptomatic of very heavy use. Check the spinnaker chute for cracks and the joint between the seat tanks and the topsides. i.e. where the two mouldings meet under the gunwale.
Centerboard case
Cracks at the base of the case, or where it joins the front bulkhead, imply that the case is moving.
Check that it is sound.
Check for hairline cracks around sheaves, spreader bracket, etc. and make sure that the mast tube is not compressed at deck level.
Look for any bubbling or swelling in the gel coat blow the waterline. This is very rare with our Class builders quality of workmanship, but it is possible if the boat has not been looked after.
Check cleats, blocks etc. If you have to replace many it soon adds up. Check that the centerboard is straight.

None of the above are the end of the world because most of them can be put right but, obviously, any problems should be reflected in the price you pay. Osmosis however can be quite serious.

Within the Association there is all the help and advice you need to take the first step. We often know of boats for sale before they are advertised.


A Guide to Basic 505 Rig Types
Many people still think, to sail an International 505 competitively, you need a very high all-up crew weight, this is untrue. By using the appropriate rig and spinnaker you can be 'in business' with a helm/crew weight as little as 23 stone (146 kg). Given that some leading crews tip the scales at 30 stone (190 kg), we are talking about a genuine weight range of 7 stone (45 kg or 100 pounds).

As already explained, Class rules allow some variation in the way that the masts are rigged. There are four basic types of rig in use at Club level and in International competition and, whilst there are further variations within each type, the following is a guide to the four groups. In North America, most top boats use a Proctor "d" based rig that uses increasing rig tension as the wind comes up, unlike several of the rigs discussed. The "straight" rig discussed, is now used by very few North American boats. Check the other tuning sheets for North American rig type and tuning ideas.

The Australians proved that, using by a 'soft' rig that depowers easily and 'gives' in the gusts, lightweight crews can be World beaters, even in breezy conditions. The mast has to allow an enormous amount of bend fore and aft and very little rig tension is used. As the breeze gets up so the jib halyard is let off, producing the mega-bend and rake that depowers the rig. The keeps the boat under control whilst the 'give' in the mast means that it is the rig that does most of the work. Sounds perfect, but some take the view that, in its 'pure' form, it lacks power in marginal trapezing conditions. Goldspar, Superspar M3, Proctor Stratus or Holt Procyon, are suitable for this configuration.
European Pre-bent
A rig that used slightly higher rig tension and appears to work effectively with a Proctor 'D' set up with medium pre-bend. It is relatively easy to set up for consistent boat speed across the wind range, and it is a long established reliable concept enjoying a major revival amongst the light to medium weight crews. Some use a Superspar M2 or Holt Antares to provide a successful, stiffer variation on the theme. A good 'all round' rig.
Generally a rig for the medium to heavy weight boys using a stiffer mast, Proctor Epsilon, 'D' plus, M2 or Antares, a little pre-bend and fairly high rig tension. These are powerful rigs that need to be fully adjustable and are designed to be slightly easier to use than the 'American' straight rig, from which it was derived.
A rig that found success in the early '80's, particularly with the Americans. The mast, usually an epsilon or 'D' plus, is held straight in most conditions, using loads of rig tension and effective bend control on the lower section. Control systems have to allow this rig to be easily adjusted as it is sensitive to small changes in wind speed. This makes the set-up more complicated to use and its critics make the point that the helm can spend the whole race 'with his head in the boat'. However, most agree that when it is right it is probably the quickest rig there is. The lack of 'natural give' makes it hard work to yacht effectively in a breeze and it is really only suitable for the heavier crews.

We believe that in the choice of rig types there is a rig which will suit almost any crew/helm weight combination.

The other consideration of course is the spinnaker. The finest sailmakers in the country all work to develop faster 505 sails, success in the International 505 is important to them. The range of spinnakers is extensive, from 'flat little ones' to 'rather large big ones'. Those most commonly used are the designs that are somewhere in the middle. For some reason, members of the 'crews union' demand 'poof blocks', more properly known as ratchet blocks, to help control these things and, to be honest, after a long hairy three-sail reach across waves, one would have to agree with them.

Basic Tuning by Ian Barker

One thing all 505 sailors know is the importance of boatspeed. Hours of time and thousands of pounds are spent on our favourite and we all want to win.

So how do we get that elusive edge?

One thing we should all realize is that as the wind changes, from nothing to very windy, we must adjust the rig accordingly How we adjust it depends largely on the rig used. Different mast sections, sails, even hulls and foils, all need to be adjusted in different ways.

As the Proctor 'D' is the mast section used by most crews, including me, these tips are based on the rig.

The most important starting point is to calibrate all controls on the boat properly. When I say properly I mean having an easy to read scale, one which can be seen easily when racing.

The most important starting point is to calibrate all controls on the boat properly. When I say properly I mean having an easy to read scale, one which can be seen easily when racing.

Some of the very best sailors may have the ability to guess quite accurately most of the settings during a race, but they will not remember all of the settings all of the time.

What you should be aiming to do is write down "on the boat", a list of the fastest settings for all controls in all the wind strengths. Only then can you quickly, accurately and with confidence, adjust your rig to the maximum boat speed for any change of wind strength.

We will now run through the controls, one by one, and discuss the effect of each one.

Jib Halyard
The is the most important control on the boat and must be the basis of sorting out a set of numbers for any given wind strength. It works quite simply, pull it on and the mast goes upright, giving more power to the rig, let it off and the mast falls back, or rakes, and the rig loses power, or de-powers.

To decide what the correct mast position is, I tend to set it up so the rig is just overpowered in a given wind strength. That means that in order to keep the boat flat, (and we all do sail flat don't we?), I have to adjust the boom in and out from the centerline a little when sailing to windward.

If the mast is too upright you will get excessive back winding, the boat will "trip up" in a gust rather than accelerate, and you'll be playing the main too much dropping the boom too far off the centerline.

If you are raked too much then the main will be pulled hard in all the time to try and get the boat upright, your crew will be dipping in the water too often, and you will lose pointing ability.

So you should be aiming to get in between these two positions. In very gusty conditions set the rig for the correct trim in the lulls, and go for pointing in the gusts.

As I said earlier, we are dealing with the type "d" rig. The following may be different for other mast sections, or extreme crew weights.

In very light winds, 0-5 knots, when the crew is not on the wire on a beat, you should pull the shrouds on very hard to bend the mast in the upper half, this has the effect of flattening the top of the mainsail allowing the leech to twist of, you can then sheet the boom on the centerline and keep the top telltale flying.

As the wind increases, and the manual labour gets out on the wire, his volume of lard will bend the mast even more. This will make the main too flat, so just led the shrouds off so the leeward one goes ever so slightly slack, leech tension on the main is then regained.

As the wind picks up even more, the leeward shroud should be getting slacker and slacker, until in 20-25 knots of wind it is flapping about.

In reality, because the mast is always raking back on the jib halyard as the wind increases, you shouldn't have to adjust the shrouds much at all.

Strut (Chocks, Rams, etc.)
This is also one of the most important controls on the boat, and the one which is the hardest to "feel" whilst sailing. It is vital to know exactly where to put the strut in each wind strength. Because the only way you can tell if it is right on the water is to judge against the opposition, if you get it wrong, by the time you've worked it out you've lost distance.

The best way to get this right is during boat tuning.

Jib fairleads
I am convinced the athwartship tracks are far superior to tracks on the inside of the tanks, or barber hauler. As the wind increases the Fairleads should be moved out from the centerline to provide forward speed and a clear slot, rather than tripping the boat and a squeezed slot.

In all the tuning I have ever done, the biggest difference in boatspeed, between otherwise equal boats, has been due to the position of the fairleads. Also, as the wind increases and you move them out, the sheeting on the jib reduces, which is what you want.

It is very hard to quantify how much kicker to use, it varies with so many different factors, basically on 0-6 knots do not use it all on the beat, but use mainsheet tension to control twist, (keep the top telltale on the main flying). Between 6-17 knots use the kicker to control mainsheet twist and move the boom in and out. In 18 knots and above, use as much kicker as possible without making the boat trip up all the time, or breaking things.

I currently use a 24:1 system which is ample.

This control is little used to windward except when you are massively overpowered. You will find if you use too much you will loose your pointing ability. Having said that, if your crew weights less than 13 Stone, it may be necessary.

The only other time the Cunningham is used is on a really tight reach to de-power the main, then pull it on really hard.

Centerboard position
I use marks on the handle of the board to calibrate this. In 0-8 knots it is angled forward 5-10 degrees, in 8-12 knots it is straight down, in 12-20 knots it rakes back 20 degrees, and in over 20 knots it rakes back 30 degrees.

The basic principle is, as the rig takes aft, the centerboard follows it to maintain balance on the tiller, making the boat easier to steer.

Main Outhaul
This depends on the make of sail you use but in general keep it tight to windward.

OK, so now we have calibrated the controls in the boat and we know what each control does to affect boatspeed. Now all you have to do is draw up a table (based on my guide chart) mounted "on the boat" of all controls mentioned against wind strength, and every time you boat tuning, or go fast in a race, fill fill in the table to compile a list of settings that can be reproduced time after time. When done, this will allow you to concentrate on the race whilst going at full speed.

All that you have to do now is "do it"!

Rig Tuning Guide for Ian Barkerís Championship winning boat,
using Proctor ĎDí mast, Rondar boat, Pinnell & Bax Sails

Wind Speed (knots) 0-4 4-8 8-10 10-12 12-14 14-17 17-22 22 up Mast Rake 25' 5" 25'4.5" 25' 4" 25' 3" 25' 0.5" 24' 10.25" 24' 10.5" 24' 9 3/4" Shroud Tension 470-490 430 350 300 300 280 260 260 Kicker No No A bit Yes Yes Loads Loads Loads Cunningham No No No No No No Yes Yes Jib Fairleads (from centerline) 19 5/8" 20" 20 1/2" 20 7/8" 22 1/2" 22 1/2" 24" 24" (from deck) 1 1/8" 3/8" -3/4" -3/4" 0 0 3/8" 3/8" Strut (from neutral) 0 0 d 1/8-1/4 0 u 1/2" u 1/2" u 1/2" u 1/2" Jib luff tension no no no a hint of no no tension a tension a creases creases creases creases creases creases little little Centerboard position 10 10 5 0 0-5 20 20 30 degrees degrees degrees degrees degrees degrees degrees degrees forward forward forward aft aft aft aft Outhaul V. tight Tight Tight Tight Ease 1/2" eased 1/2" Eased 1/2" tight"