Question details:

At certification, when the difference between the QBL dimensions is found to be outside the class rule limit, what is the correct action?


Large differences in the QBL lengths will occur due to one or a combination of the following:

  • lack of symmetry of the hull
  • placement of the hull off the centreline of the measurement equipment
  • lack of alignment of the hull with the centreline of the measurement equipment

As the permitted sail area can be increased (where there will be a QBL penalty) by enhancing the difference in port and starboard QBL measurements, the class rules specify a limit to that difference.

There is no requirement in the class rules for the centreline of the hull to be on the centreline of the measurement equipment. Moving the hull laterally on the measurement equipment can restore equality in the measurements. A rule of thumb that can help here is to move the hull one fourteenth (1/14) of the difference between the QBL measurements towards the side of the shorter measurement.

Alternatively, if the owner is prepared to lose some permitted sail area, the lower QBL dimension can be raised artificially to within the specified difference from the larger QBL dimension before recording.

Question details:

How close does the headsail tack, luff spar or boom swivel need to be to the centreline for compliance with A CR 8.4 (b)(2)


The word ‘approximately’ appears to introduce some latitude in the placement. As most boats are asymmetrical to a greater or lesser degree, making it impossible to define a centreline precisely, the requirement is that the attachment shall be approximately on the centreline.

For the same reason, it is impractical to state a maximum distance within which the attachment shall be made.

Generally, an attachment within 5 mm of the centreline will be compliant. Where a hull is conspicuously not symmetrical, this figure may be larger.

Question details:

When an A boat which has been originally measured under the previous class rules is remeasured, would that be under the current or the original class rules?



If a boat is being re-measured it is almost certain that this is because its flotation or other dimensions have been changed - that is A.11.1 a), b) or c) apply. A.12. 1 (b) is another possible reason. A.11.2 tells us what can be done when a boat ceases to comply with the class rules (which include its certificate) and option a) is for an official measurer to carry out certification control (i.e. re-measurement) of affected equipment (in this case, the boat).

The boat shall be certificated to the current class rules. However,  Sections D, E, F, G each tell us about possible grandfathering in cases where previously permitted equipment has become non-compliant due to class rule changes.

The hull shall comply:
(a) with the class rules in force at the time of its initial certification control;
(b) with the class rules relating to its certificate; or
(c) with the current class rules.

The hull appendages shall comply:
(a) with the class rules in force at the time of its initial certification
control; or
(b) with the class rules relating to its certificate; or
(c) with the current class rules.

(a) The spars and their fittings shall comply either with the class rules in
force at the time of the initial certification control of the hull or with the
current class rules.
(b) The standing rigging and running rigging shall comply with the
current class rules.

The sails shall comply either with the class rules in force at the time of their
initial certification control or with the current class rules.

Question details:

Is a GIZMO and its derivatives, also known as BRESMO etc, permitted in the 65 Class? This device is actuated by the sheet of a swing rig when the rig is sheeted fully in and when the sheet is winched in further so that it acts on a lever or other device that automatically adjusts other rigging.



Relevant rules


The class rules for the 65 Class are open class rules in which anything not specifically prohibited by the class rules is permitted, where individual rules require, limit, or prohibit as necessary.

(a) No more than two channels of radio control shall be used.

(b) A rudder control unit shall control the rudder only.

(c) A sheet control unit shall control the mainsail sheet and/or headsail sheet only.
(d) Except where achieved by mechanical systems, automated control of rig and/or sails and automated steering and/or navigation are prohibited.


C.8.1 (c) prohibits the use of the sheet control unit for controlling anything other than the mainsail sheet and the headsail sheet. However, C.8.1 (d) makes it clear that mechanical systems that provide automated control of the rig and/or sails are not prohibited.

Hence the GIZMO and its derivatives are permitted in the 65 Class.


The pathway for classes of boat that are not IRSA designated classes is as follows:

  • Create class rules that use the World Sailing Standard Class Rules format
  • Certify boats to these class rules
  • Create an active international class association with provision for control of the class
  • Meet the numerical requirements
  • Apply for IRSA designated class status
  • Apply to run a world championship

The process is fully documented in the IRSA Regulations, a new version of which which is currently (early 2018) in the process of being considered for adoption by the IRSA DNMs. The process would apply to any class which is not already an IRSA designated class e.g. RC Laser, DragonForce, DragonFlite, RG65, Micro Magic. 


Question details:

 What equipment is optional for an A Class boat when racing?

This question is especially relevant to the Q&A concerning whether the boat may weigh less than the certified weight (less the tolerance).



Class Rule C.4.2 states that the boat shall sail with the hull, hull appendages, ballast, mast spar and main boom spar relating to the certificate. CR C.8.3 states the mainsail shall be set when racing. C.9.2 states rc equipment, if temporarily removed,  shall be replaced by items of similar weight in the same position. C.9.3 states the owner's flag is mandatory. CR F.1 states the rig shall consist of no more than one mast, one headsail luff spar, one main boom, one headsail boom, standing rigging, running rigging, wind indicators and owner's flag. CR G.1 states the sail plan shall consist of one mainsail and, optionally, one headsail.

From the above it is clear that the mandatory equipment comprises:

  • hull
  • hull appendages
  • ballast
  • mast spar
  • main boom spar
  • rc equipment of similar weight and position
  • mainsail

And the remaining equipment is optional comprising:

  • headsail luff spar
  • headsail boom
  • standing rigging
  • running rigging
  • wind indicators
  • replacement of rc equipment of similar weight and position
  • headsail

Question details:

When an A Class boat is raced without optional equipment on board, does it comply with the class rules when its weight is below the lower limit for boat weight because optional equipment is omitted?


The full text of the discussion and conclusion, under the 2017 CR and previous CR, will be posted here as a download. For the sake of brevity the conclusion is posted here:

The CR permit several items of the rig that shall be on board for certification control to be omitted for racing. The CR do not require sails to be on board during certification control. Further the CR permit the headsail to be omitted when racing.

It follows that the weight of the boat when racing is permitted to be lighter than the certified weight less the tolerance.

It follows that the weight of the boat when racing is permitted to be heavier than the certified weight plus the tolerance if the sails used weigh 200 grams or more.

At an event for A Class after 30th June 2016

At an event for A Class after 30th June 2016 the 2016 CR apply. Section C of the 2016 CR applies to all boats so this (discussion and) conclusion applies equally to boats competing under certificates issued under previous class rules.

Question details:

Should the 2016 software should be used when ownership of a boat first certified to the previous class rule changes?


No. The software for certification under the previous class rules should be used. Change of ownership causes the certificate to become invalid but it does not cause the boat to cease to comply with the class rules. A new certificate, to the previous class rules, shall be issued.

It is not possible to produce a certificate to the new class rules in the case of change of ownership because several measurements taken and used under the 2016 class rules are different to those used for the previous class rules.


A.12.1 A hull may be issued with a new certificate, showing dates of re-certification and initial certification as applicable:

(a) when a certificate becomes invalid upon change of ownership

by application of the new owner to the certification authority in the country where the hull is to be registered. The application shall include the old certificate and re-certification fee if required. In the case of an imported hull the certification authority shall request the measurement form(s) from the previous certification authority and a new hull registration number shall be issued,.

In this case there is no requirement to apply the procedure in A.9 (which describes how a hull is certified). Use of the software for certification under the previous class rules should be used.

Question details:

Should the 2016 software should be used when the owner of a boat first certified to the previous class rule elects to have his boat re-certified


A boat with a certificate first issued to previous versions of the class rules may have one or more alternative certificates issued using the process identified in CR A.12.1 (c).


A.12.1 A hull may be issued with a new certificate, showing dates of re-certification and initial certification as applicable:

(c) when one or more alternative certificates are requested to be valid concurrently with an existing certificate

by application of the procedure in A.9.

A.9 is the standard procedure for certification and no variation is necessary for a boat with a previous certificate.

Question details:

What is the point of the NANO class?


The advent of 3D printing fittings and other parts for rc boats raises the possibility of a class where the hulls and other parts are largely constructed by 3D printing and, probably, by the end user. Although this may well work in the existing RG65 and FOOTY classes, those class rules permit conventional moulded carbon fibre for the hull and deck structures and this confers a large weight/stiffness advantage to boats built using ‘hi tech’ methods

A new class rule devised specifically to cater for those who want to create their own boat, primarily by printing it themselves, would seem to be a logical step for the sport.

Such a class is an ideal one in which students of all ages can test their design and build skills. Perfect for craft, design and technology projects. The possibility of designing the boat on Friday and going racing on Saturday has become a reality.

Importantly the class raises the possibility of readily available low cost boats within an open class that is ideal for those starting the sport of rc sailing. You do not have to choose a one design with no freedom to experiment. 

Objectives of NANO class

  • Sailors are quite likely to be able to design and build the majority of their own boat
  • Hull and associated structural parts may only be made by 3D printing
  • No hull/boat certification process
  • No sail area measurement
  • Event measurement only
  • Draught/length ratio not so large that fin technology rules – 0.45 length maximum
  • Tightly controlled rig size and number

Provisional class rules have been launched in May 2017. It is anticipated that feedback from users may assist with refinement of the class rules, if required, to help achieve the desired objectives.

Question details:

Is there be a method of producing a certificate/sail measurement for the provisional IRSA 65 Class?



The sail measurement system is identical in concept to the 2016 10 Rater measurement system that has many advantages compared to the previous 10R system.

Apart from being very simple to use it produces very repeatable results and is not type forming (does not tend to encourage one partcular sail profile shape).

The 10R certificate/sail measurement software has recently been developed to give more useful information to the measurer, certification authority and sail maker. The same advantages are incorporated into the 65 Class certificate.

NB        In the IRSA 65 Class rules there is no requirement for a boat to have a certificate - compliance is to be established by equipment inspection at an event only. Each rig (spars, fittings, rigging and one or two sails) shall have its own certificate. Owners may have as many such rigs as they choose and use whichever three rigs they wish to during an event.

Question details:

What steps were taken to consult with RG65 ICA and others before release of the provisional IRSA 65 Class rules?


In December 2015, the IRSA TC started the development of a discussion rules document for 65cm long monohulls. This was based on interest from some of the IRSA National Members and in recognition that the current RG65 Class rules were not in a format acceptable to run an approved Championship.

The IRSA TC aimed to give to the RG65 community a set of rules that would suit the class and also be in an acceptable WS format.

The document went through several iterations based on feedback from the RG65 ICA representatives and other stakeholders in the ensuing months until a dedicated working party was set up within the IRSA website to accelerate the development of the class rules.

The forum included three delegates from the RG65 ICA and three from the IRSA along with a large observer base from stakeholders and interested parties from around the world. The observers were allowed to introduce ideas through any of the delegates present.

This working party ran from March 2017 to December 2017. Each part of the draft rules was analysed and discussed. This resulted in a document called the 65 Class rules which has since been approved by the IRSA EC and is now published on the IRSA site under Classes.

It needs to be noted that the RG65 ICA has requested that these 65 Class rules should not be confused with the current RG65 Class rules under their care.

The 65 Class rules are, in a sense, a “generic” set of rules that could help any class of this size to develop and run a “Championship Event”

Question details:

How large can the sail maker label be on sails? Or the manufacturer label on other items of equipment? The class rules do not restrict this?


The relevant rules are contrained in the World Sailing Advertising Code, also known as Regulation 20.

Clause 20.7.1 states that the display of manufacturer's and sailmaker's marks is permitted at all times as detailed in Table 2 but not in areas that area reserved for Event Advertising. For radio controlled boats the area reserved for Event Advertising is 40% of the hull length on each side of the hull from the foremost point on the hull. No Event Advertising is permitted on the boom(s), backstay or sails.

20.7.2 tells us a manufacturer's mark may include the name, logo or other identification marks of the designer or manufacturer of the equipment.

20.7.3 tells us that a sailmaker's mark may include the name, logo or other identification marks of a sailmaker or of the sail cloth manufacturer or the pattern or model of the sail.

Table 2 – Manufacturer’s and Sailmaker’s Marks

Radio-controlled boat

Hull  - On each side of the hull, and may include the name or mark of the designer or builder - One mark to fit within a rectangle measuring 15% of hull length x 150mm                     

Spars and Equipment - On each side of spars and on each side of other equipment - One mark not exceeding 50mm length                    

Sails - On each side of sails and kites - One mark to fit within a 50mm diameter circle






Question details:

How does A Class rule G.3.2 (e) work where there are no batten pockets or battens?



G.3.2 (e) requires the batten pocket point to be found.

The batten pocket point is defined in the class rules as

"the intersection of the extended centreline of the batten pocket, or batten if there is no batten pocket, and the leech."

This case is much the same as a missing limit mark on the mast. If there is no batten pocket or batten the point cannot be found and the measurement cannot be taken. The official measurer should decline to sign the measurement forms (signing would indicate he had completed the task satisfactorily) or report that the measurement of the mainsail is incomplete on the measurement form and the certification authority will refuse to issue a certificate.

In practice the owner should be asked to add something that resembles a batten pocket (tape) or a batten (self adhesive glass sheet) in an appropriate place and the measurement (and in G.3.3) can be taken successfully.

Question details:

What does a race committee do when a boat has sail marks that are not clearly legible or compliant with the RRS?


A little history first - going back a couple of decades the sail identification marks rules were in the class rules and measurers were required to check that marks complied with those rules. In principle this ensured boats had compliant sail identification marks. But in practice, for various reasons, a proportion of boats had marks that did not comply.

Race committees and juries tended to avoid pressing the issue - it was a measurement issue not a racing rules issue and, therefore, not their problem. Taking the sail marks (except for the insignia) out of the class rules solved several problems - most importantly, compliance with the sail marks rules was a racing rules issue and was clearly something the race committee and jury had full and sole responsibility and authority for dealing with. Other problems solved were harmonisation across the classes, the possibility of sail certification (measurement) without application of the numbers and letters, a saving of measurer time when certifying (measuring) sails, and the freedom for the owner to change the sail numbers without having to engage the measurer (something that was rarely done anyway).

A boat that has marks that are not clearly legible infringes RRS App G1.1. There are several other ways that marks may fail to comply with this rule and App E - please see the Q&A under Sail Identification for some examples. In either case the race committee may be affected because it may have difficulty identifying the boat in question during a recall or when finishing. Competitors, umpires and judges may be affected when attempting to protest the boat. This is a fairness issue and, therefore, one which an international jury can be asked to advise on by the race committee (see App N2.1).

In the first instance the race committee, or an equipment inspector or technical committee at a major event, should advise the sailor that his sail marks do not comply with the RRS and that the boat will be protested if it races without suitable amendment to the marks. Hopefully he will respond appropriately. Provision of a black marker pen may help him comply. Provision of acetone to remove inked marks may also be useful. With average care self adhesive numbers can be removed without damaging sails and no are excuse for non-compliance.

If the sailor fails to respond in an appropriate way the race committee or technical committee can (and should) proceed as soon as the boat races as it would for any other breach of the RRS by making a protest against the boat under RRS 60.2/60.4.

When a protest committee finds that a boat has sail identification marks that are not compliant it shall either warn her and give her time to comply or penalise her. See App G4. As the penalty is not prescribed by the RRS it is one that is discretionary i.e. it can be scaled to suit the specific case. International juries will be familiar with the Discretionary Penalties guide - there is one in preparation for RC sailing.











Question details:

Are the sail marks shown below compliant with the RRS as modified by Appendix E?


RRS Appendix E8 G1.4 (a) requires national letters to be in 'capital letters'. The 'K' in this set of letters does not look like a capital letter in the same type face as the 'U' and 'R' so these do not comply.



RRS Appendix E8 G1.4 (a) requires marks to be of the 'same colour'. It also requires them to be 'clearly legible'. These numbers are formed by infilling a black outline with green so they do not comply with the requirement to be of the same colour. They may also fail on legibility because the green is not as opaque/dark as other colours.



This set of national letters fail to comply for the same reason.



RRS Appendix E8 G1.4 (a) requires marks to be 'clearly legible'. Where the body of the sail is a mix of materials of different colours there can be problems choosing a colour for the sail marks that will meet the 'clearly legible' requirement.

Here the owner has used white marks instead of black. Are they 'clearly legible'? Would black sail marks be more 'clearly legible'? If the appointed equipment inspector at an event reports this to the race committee they shall bring a protest against the boat which the jury will decide on. 



RRS Appendix E8 G1.4 (a) requires marks to be 'clearly legible'. The race committee at the world championships in Lake Garda, 2016, complained about marks that had strokes that were relatively thin because they were not very legible at a distance.

The same or better legibility than Helveitica is acceptable. Assuming the standard (not bold, narrow or condensed) font is meant by this the ratio of stroke thickness to height for Helvetica is between 12 and 14% of the height. The example below looks less than this and is likely to be less 'clearly legible'.

P1030960        22


This set of national letters probably fail to comply for the same reason. The gaps created by the use of a stencil do not help.



The vertical spacing of marks is controlled by RRS Appendix E8 G1.5 (a). Where there is sufficient space available on the sail this is currently a minimum of 60 mm.

The example here does not meet that requirement.



The height of marks is controlled by RRS Appendix E8 G1.4 (b) which specifies the height of numbers to be 100 mm mimimum and 110 mm maximum. The variation in these is greater than the permitted variation.

The spacing of marks is controlled by RRS Appendix E8 G1.5 (b) which specifies the spacing of numbers to be 20 mm mimum and 30 mm maximum. The spacing in these is less than 20 mm.



Question details:

How might a rc foiling class take off?


There are not many such boats around so, even if they did all meet the criteria suggested for an international class, it seems unlikely that fleets large enough for a meaningful race would exist for a while. However, if the boats met the suggested criteria a comparison of speed, perhaps around an agreed size and format of course, becomes a useful comparison of achievement level.

A 'speed week-end' where boats gather and are timed around a course might be an interesting starting point too.

Question details:

Class rules for an international foiling class? What may be useful restrictions in a class rule for a foiling class that might become an international class? 


There seems to be some interest in creating foiling multihulls for rc sailing. It may be useful for those developing such boats to be contrained by some restrictions so that the boats may fit within a 'class'. Comparisons of performance, whether measured by speed, foiling ability, manoeuvrability or some other criterion, then become meaningful. For this reason, and to assist those who are experimenting with such boats to move more quickly towards an international class should they wish to form one, a sub-committee of the IRSA TC led by Ian Holt has considered what restrictions might apply.

They can be summarised as:

  • The Mini40, MultiOne classes may be suitable starting points
  • Alternatively a 1 metre x 1 metre box may be a suitable restriction for the hull(s)
  • Foils should be permitted to extend outboard of the hulls but that restriction should be limited to a modest figure, say 100 mm
  • Automation of control should be permittted
  • The type of course might be prescribed in the class rules
  • Rig height should be restricted
  • Measurement of sail area may be unnecessary *
  • A minimum weight (without rig) might be useful **
  • A maximum draft of not more than 700 mm ***

 To expand a little on these:

The speed of a foiling boat can be high and is not linked to length as in monohull keelboats. A small hull size helps with transportability and construction.

It has been found easier to add foils to the outside of hulls but their extension should be restricted so that RRS 11 can be complied with easily.

On board computing that imparts a degree of autonomous control (height, pitch etc) much like that given to a drone, and for sail/rig control, would make sailing the boats easier.

Windward ability may be limited and class rules that prescribe a short beat and long reaches may be preferred to the traditional rc sailing course.

All the other international rc sailing classes now restrict the maximum rig height/mainsail luff length in some way - this is useful as it keeps rigs small enough to fit into a modest size car and permits them to be transported economically by plane. A minimum rig height (no smaller than for an IOM) would ensure no problem with placement of RRS App E size sail marks. It also sets a virtual upper limit to wind speed used for racing and a clear boundary so sailors can be properly prepared for the 'worst' conditions they will need to cope with.

*   Ian Holt noted that sail area was not really an important speed limiting factor except a very low wind speeds.

**   I suggest a minimum weight (sailing condition less rig) might serve to constrain how hi-tech construction methods need become in the longer term in order to keep the class open to those whose building techniques are not of the highest levels. An important factor if the class is to be open to many.

*** IRSA regulations precribe that a class may choose a maximum draught of not more than 700 mm. This is so that a race committee can ensure sufficient water depth for all boats over the course area for their event.


Question details:

Does the Certification Authority have to use an official stamp in the relevant place when issuing a certificate?


There is no prescribed requirement for the size or style of ‘official stamp’. At an event the person inspecting the official stamp on a certificate has no means of knowing if it is the correct one or not. The important thing is that the issuing Certification Authority will recognise it at some future stage should the certificate be referred back to it for any reason.

Any size or style of official stamp will suffice providing the CA is happy that it can recognise it as authentic at a later stage.

Question details:

Can the aft QBL measurement points be on the transom?


1994 Class Rule

The 1994 A CR 3.2.4. states that "QUARTER BEAM MEASUREMENT POINTS are located on the surface of the hull one tenth of the waterline beam above the waterline and one quarter of the waterline beam from the centreline". The question is whether the transom is a part of the hull? Transom is a part of the hull according to the Equipment Rules of Sailing. Before the transom was included in the ERS definition of hull there was an interpretation in the Ten Rater Class that concluded the transom was part of the hull. There is, therefore, no reason to think that the definition of the hull in the Equipment Rules of Sailing, although not applicable for the 1994 A CR, should be unfamiliar to the average measurer/ builder/designer.

Quarter Beam Measurement Points may be located on the transom in accordance with requirements of A CR 3.2.4. Attention is drawn to the requirements of A CR 3.3.3 – the restriction on hollows in the surface of the hull apply equally to the transom.

2016 Class Rule

The QBL measurement points are required to be on the external surface of the hull shell (CR H.5.9). In ERS D.1.1 the hull is defined as 'The shell including the transom,.....'.


In other words, do you have a particular skill or experience that can help with the operation of the IRSA?

The IRSA is an association that serves over 30 National Organisations that maintain and promote Radio Controlled Sailing in their countries. Through these national bodies, the IRSA also serves the RC community as a whole, particularly being focused on the Internationally Recognised classes (10R, Marblehead, A-Class and IOM) and assisting emerging international classes. IOM sailors are served by their own international class association (ICA) called IOMICA, which is affiliated to the IRSA under a contract.

So you want to help?

There are many different aspects of the IRSA work that needs keen, skilled and enthusiastic people.

  1. Treasury and finance. 
  2. Interpretation and changes to the Racing Rules of Sailing. 
  3. Supporting the logistics of running World and Continental events
  4. Interpretation and changes to the class rules and measurement procedures.
  5. Development of international classes for those classes that are spread across the globe and can be indentified as being truely international.
  6. Organisation of the IRSA structure, in terms of ongoing analysis of the constitution and the various rules and regulations that direct the operations.
  7. And, there are other ongoing and sporadic needs.

Speaking of the Executive, the IRSA is divided into distinct working groups.

  1. The Executive Committee. This group are nominated and elected by the national bodies and IOMICA every two years. Each has their own job, so to speak, and often come together to discuss and sometimes vote on matters on the Executive Forum.
  2. The Committees. These assist in the development of various rules, interpretations and advice as matters turn up. They are invaluable to help the committee chairmen (who sit on the Executive) to bring quality and well thought through matters to the Executive for ratification or revision.

So where could a keen volunteer fit in?

If you wish to be part of the Executive, you will have to wait until the next General Assembly in April 2018. Apply to your national organisation to be nominated to the position you feel you can bring some solid expertise to.

If you wish to be part of a committee in the areas outlined in 1-6 above, and feel you have the experience and background to bring quality advice to these committees, then please don’t hesitate.... apply to your national body to be nominated. ​

The nomination does not mean you will automatically be involved. The nomination will be reviewed by the Committee Chairman and then the Executive and you will be required to supply information like sailing background and experience in the area you are applying for. There is no limit to the number of committee members, but you are required to be very proactive when the need arrives.

Please note.

IRSA does not take nominations directly from individuals, only the member national bodies. So all applications need to be forwarded through the national member of your country. Also, there is a limit of two volunteers per committee per country.

Looking forward to you joining a dedicated group wanting to put back into this beautiful sport and continue the considerable momentum already built up.  


An event can be run using "single certificates"

If it is considered desirable at a particular event to ensure a sailor cannot choose the best configuration to suit the prevailing conditions, the event organiser can issue a Notice of Race, and a Sailing Instruction, requiring a certificate to be lodged at some prescribed time ahead of the event and to use the boat in that configuation. This also prevents owners of multiple boats from choosing which boat to use at the time of the race.



Starting in around February 2015, class rule changes were introduced and discussed within the IRSA Technical Committee. The proposed rule changes were circulated to IRSA Designated National Members (DNMs) around December 2015 and January 2016. A number of DNMs responded with comments, and these were addressed by the TC Chairman. The proposed revised class rules were then brought to the Executive Committee by the TC Chairman in March 2016, which the EC formally voted on and approved. The rules, and an explanation of the changes, were published in April 2016, and came into effect in July 2016 after minor errors were found and edits made. This is the process which has been used in the previous decades of rule changes by the IMYRU, ISAF-RSD, and now IRSA.  


It is inevitable that a new set of class rules may have a rule which is thought to be in error or in need of amendment. Suggest a rule change to your DNM. If it agrees, or if you are the DNM, send it to the TC Chairman for further discussion. Please read carefully our regulations and Q&A to avoid unnecessary work before you send any suggestions to the TC. Proposals for rule changes should be based on meaningful technical evidence and not on loud repetitions.  


Where no ICA structure exists for an IRSA class, the IRSA sets up a class committee within the association and works towards growing this committee to the point where it can stand alone as an ICA.  Of course there is always the opportunity for a non IRSA association to take up that role.


As the IRSA 65 Class has provisional IRSA status the pathway is now straightforward: 

  • Apply to IRSA to hold a world championship 
  • Run the world championship

Boats will be eligible for the event only if their certification complies with the IRSA 65 Class rules. There is no prohibition on boats complying with and being certified to the IRSA 65 Class rules and, at the same time, complying with and being certified to the RG65 Class rules.

Question details:

Could the owners of boats that are not yet an IRSA designated class create their own class rules to the World Sailing Standard Class Rules format (as a precursor to applying for IRSA status and a world championship)?


Of course, but it may take longer to arrive at a result that is satisfactory to IRSA. 

This would apply to any class which is not already an IRSA designated class e.g. RC Laser, DragonForce, DragonFlite, RG65, Micro Magic.


The draught limit is to ensure all boats at an event can be guaranteed to be able to sail. From an IRSA point of view it is imperative that the race committee of an IRSA event does not find itself embarrassed because some competitors with class rule compliant boats cannot compete.  


You can find the provisional IRSA 65 Class rules under the relevant sections of this website (look under Documents and/or Classes).

In creating the IRSA 65 class rules, based on the RG65 class rules, the guiding principles have been:

  • The class rules are written in the WS SCR format using terms defined in the ERS. 
  • The sail measurement system is specified 
  • Ballast materials denser than lead are prohibited 
  • A draught limit is introduced 
  • Sail marks rules are rationalised with those in Appendix E of the RRS 
  • The rules for racing are specified as the RRS. 
  • Changing the fin/ballast unit after each day’s racing is prohibited. 
  • Measurement and certification of boats is by independent official measurers 



The major differences are:

In the IRSA 65 Class rules

  • The class rules are written in the WS SCR format using terms defined in the ERS.
  • The sail measurement system is specified
  • Ballast materials denser than lead are prohibited
  • A draught limit is introduced
  • Sail marks rules are rationalised with those in Appendix E of the RRS
  • The rules for racing are specified as the RRS
  • Changing the fin/ballast unit after each day’s racing is prohibited
  • Measurement and certification of boats is by independent official measurers


Class rules written using the WS SCR format ensure that as far as possible the language used and the certification (measurement) methods employed by the class rules are harmonised across the classes. Designers, builders, sail makers and measurers can then be confident of having a common understanding of class rules. This makes it easier for manufacturers of equipment to create products that are less likely to be found to be non-compliant by measurers.

Commonly used words like ‘boat’, ‘hull’, ‘hull appendage’ and a vast number of other similar boat part names, when printed in bold text as here, are all very precisely defined in the Equipment Rules of Sailing (ERS). The ERS is a stand-alone document available as a download from the WS and IRSA websites. 


To gain IRSA designation some straightforward, but important, standards have to be achieved. 

  • The class has to have a certain number of boats across a certain number of continents and countries. 
  • The class rules have to be written to a common standard, the WS Standard Class Rules (SCR) format.

These requirements would apply to any class which is not already an IRSA designated class e.g. RC Laser, DragonForce, DragonFlite, RG65, Micro Magic. Whereas the numerical requirements may be met in all or most of these cases (please see the IRSA Regulations for these), the requirement for WS SCR format class rules is not.


The RG65 class appeals to a large number of builders because they can exploit exotic construction methods without the problems associated with larger scale building projects. Construction can be as convenient as on a kitchen table. Sail making can be accomplished in a relatively small space. The class is a ‘development’ or ‘open’ class so builders have freedom to improve performance that is deliberately blocked in ‘one design’ or ‘closed’ classes.

The boat with all its rigs will comfortably fit into a well designed pack not much bigger than a box used to transport an IOM hull. The prospect of travelling by public transport, as well as by plane without having to pay for excess baggage, is a realistic one. The restriction on the number of rigs serves to restrict cost and complexity, and the boats can be sailed in a space as small as an Olympic swimming pool. A well set up RG65 performs remarkably well, so it is easy to see why the class is popular.

While the RG65 class rules do not meet the required standards for the class to become an IRSA designated class it is not possible for the class to hold a world or continental championship. However, it is consistent with IRSA’s constitutional object to develop the sport of rc sailing throughout the world to lend support to the sailors of any class that is popular internationally. For this reason the provisional IRSA 65 class rules have been created.

Creating a provisional IRSA 65 Class opens up the possibility of world and continental championships. Robust class rules are now in place so that continued participation in the class is not adversely affected by escalating costs. In this way it is believed the class will attract greater numbers of participants and the level of competition in the class will increase enormously. For these reasons IRSA is interested in assisting the class. 


No. Such an event would be defined by World Sailing as a prohibited event.

Some time back WS delegated responsibility for the international administration of radio sailing to IRSA and it is through this affiliation that IRSA is able to grant the right to run WORLD and continental championships in the rc international classes. WS protects the right to call a sailing event a world or continental championship – claiming an event is one when it is not sanctioned by WS or IRSA is a breach of the WS rules and can result in competitors being excluded from legitimate sailing events.

IRSA is the international class association for the Marblehead, Ten Rater and A Classes. The International One Metre has its own independent international class association, IOMICA, that is responsible for the administration of the IOM class and which is affiliated to IRSA. All these classes hold world championships from time to time and the events are run under the guidance of IRSA’s & IOMICA’s regulations using the well known Appendix E of the Racing Rules of Sailing (RRS).

In order that any class may hold any event titled ‘world championship’ or '(continental) championship' it has to have IRSA designated status. However, the classes that are not already IRSA designated classes e.g. RC Laser, DragonForce, DragonFlite, RG65, Micro Magic, have a clear pathway to follow (see IRSA Regulations) if they wish to pursue the goal or holding world or continental championships.


Question details:

Use of boats with certificates issued by sources other than IRSA affiliated bodies?

Is it possible to enter an event described in the NoR and SIs as for boats of an international class (IOM,. M, 10R or A Class) with a certificate other than an IRSA certificate issued by a body affiliated to IRSA?



The IRSA international classes are distinct from classes using the same name but which are not administered (ultimately) by IRSA. For example the Naviga administered One Metre, Marblehead and Ten Rater classes are different classes and the certificates issued under those rules are not valid for IRSA events (world or continental championships) or events normally organised by IRSA affiliated bodies. The same is true for the Marblehead class administered by the American Model Yachting Association which uses class rules different to the international class rules.

The owner of a boat in one of those classes can obtain a certificate for the international class after having his boat measured to the IRSA class rule. To do this he should find an official measurer (please see the Equipment Rules of Sailing) and then contact his certification authority (normally the body in his country that administer rc sailing and is affiliated to IRSA). If he is a member of a body affiliated to his World Sailing Member National Authority (the body responsible for the administration of SAILING in his country) he will then be eligible to take part in events for the international class.

Question details:

A Ten Rater has its largest sails measured for the purpose of establishing its rating. Those sail sizes are entered on the measurement form and are recorded on the certificate. The same is true for an A Class boat and for a Marblehead (usually the largest of A rig, of B rig and of C rig). Is it necessary to have smaller sails measured and certified?



The smaller sails are measured to ensure they are indeed smaller and that they meet the other requirements and restrictions. Then they are certified (usually by the measurer signing the sails) to show that this porocess has bene completed satisfactorily.

Question details:

At what point, on change of ownership, does the certificate become invalid?


The certificate becomes invalid upon a change of ownership. The change of ownership is the important criterion – not the signing of the certificate by the new owner – not the issue of the new certificate in the new owner’s name.

However, while the concept of ownership is normally well understood between any two people it may be that the law of the land becomes relevant in particular cases and this may vary depending on the contract involved and where the ‘transaction’ takes place.

The view is that IRSA class rules are not intended to, nor do they, shed any light on ownership or when it changes hands.

Question details:

When the foot of a double luff sail falls below the lower limit mark, does it comply with the class rules?


The class rules (Marblehead and A Class) require that the tack point shall not be set below the upper edge of the lower limit mark. The tack point is normally aft of the mast spar but on a double luff sail (specifically a pocket luff sail) it may be forward of the mast spar. In this case it may be that the foot of the sail overlaps the lower limit mark (as shown on the diagram). There is no requirement in either class rule that the foot of the sail shall be above the lower limit mark.

A sail set as shown in the diagram complies with the class rules.

tack point_and_lower_limit_mark

Question details:

What is the difference between a Q&A and a Class Rules Interpretation?


An interpretation is requested when it is not clear (to a designer, builder, measurer, class association or certification authority) how a class rule shall be interpreted. When an interpretation is issued it should be kept in mind that the interpretation is valid until the class rules are changed or for two years maximum only. The purpose of this last rule is that two years gives sufficient time to consider if the effect of the interpretation is a) desirable or b) undesirable. Depending on the decision or choice (a or b, by the IRSA TC or the class depending on whether there is an independent class organisation or not) the class rules can be revised accordingly.

Thus, when drafting any interpretation, it should be kept in mind how the class rules should/could be revised to make the original interpretation request redundant.

It follows that, if no revised class rule can be written, there is no need to issue an interpretation. Where no interpretation is required, but only an explanation of the effect of the class rules, it follows that it would be appropriate to deal with the original request by issuing a Q&A to be published on the IRSA website and elsewhere as appropriate.

This is the guiding principle used by the IRSA Technical Committee when considering any question about the class rules whether it is a formal request for an interpretation or not.



The ERS is a document maintained by the ISAF which is a revised on the same 4 year cycle as the Racing Rules of Sailing. The current version may be found on the ISAF website and there are several versions in translation listed there too.

Question details:

Section C of the class rules requires the hull registration number to be displayed legibly on the external surface of the hull with a minimum height of 20 mm.

Section D of the class rules requires the hull registration number to be permanently marked on a non-removable part of the hull surface.

Can a single set of hull registration numbers satisfy both rules?


Yes. Providing the hull registration number digits are of minimum height 20 mm, are clearly legible, are easily visible, are painted, engraved, bonded in or moulded in, and are on a non-removable part of the hull then both rules are satisfied by a single set of numbers.

However, it is often more convenient and attractive to use vinyl numbers on the deck to satisfy the Section C rule and some more convenient method on an inside area to satisfy the Section D rule.

Bear in mind the purpose of the rules: the Section C rule is for the benefit of the race committee and other competiors at an event to help identify a boat when it does not have it's rig in place; the Section D rule is to permanently and uniquely identify a boat so that it may be grandfathered, if needed, at a later date. In 50+ year's time the number will also add value and interest to any boat that has survived that long.

Question details:

A recent ruling for the IOM class says the certification authority for the hull is the DNM of the country where the owner is resident.  Does this apply to the M, 10R, and A Classes too?



The IOM, Marblehead, Ten Rater and A Class class rules indicate the certification measurement forms (measurement forms) are sent to the certification authority in the country where the hull is to be registered. This seems to give the owner some choice over where his hull is to be registered.  However, ERS C.3.1 defines the certification authority as 'the MNA of the owner'. Where the term certification authority is used it shall be understood to be the certification authority in the country where the owner is resident or in the country of which the owner is a national. This is normally the DNM (Delegated National Member for radio sailing) in the country.

Question details:

Who issues a certificate for any of the IRSA classes?






The certification authority issues the certificate. As of 1st July 2016 all the IRSA classes have the same administrative section. It is A.9 that indicates it is the certification authority that issues a certificate.

The term 'certification authority' is defined in the ERS as:

For the hull: the ISAF, the MNA of the owner or their delegates.

For other items: the ISAF, the MNA of the country where the certification shall take place, or their delegates.

The members of IRSA are the bodies to which the administration of RC sailing has been delegated (if not the MNA of the country itself) and which are known as the DNMs. So, for the hull it is the IRSA DNM of the owner.

For other items it will usually be the same but it could be the MNA or delegate of MNA in another country where the emasurement took place. This would apply where, for example, sails were certified in house by a sailmaker who had been delegated the authority to do that.

See also the related Q&A concerning who is the certification authority, or DNM, for an owner.

Question details:

What sail identification marks shall be displayed when a hull holds a certificate in more than one class.


When a boat races it shall carry the appropriate sail identification marks for that class. Providing they do not affect the legibility of the marks, alternative class insignia may remain on the sails.


No. C.6.3 prevents the movement, articulation, retraction or extension of hull appendages (including the ballast). Additionally RRS 51, which is not excluded by Appendix E of the RRS, states that movable ballast ‘for the purpose of changing trim or stability’ is not allowed.

1994 CR 4.1.1 prevents movement of the ballast fore and aft and canting keels per se are not prohibited. However, when a race is un using the RRS and RRS 51 is not cancelled the effect is the same.

The same logic applies to the other classes too.


Yes. Class rule C.7.2 applies to the spars, which may not be replaced unless lost or damaged beyond repair, and does not apply to the rigging or fittings on the mast and main boom.

The 1994 A Class rules do not use the ERS definitions so the requirement to use the original mast and/or main boom should be understood to apply to their spars i.e. the structural members to which fittings and rigging may be added.

Owners are reminded that the boat shall still comply with other class rules (weight, flotation etc) that may be affected when rigging is changed.


Except when the original mast spar or main boom spar are damaged, no. CR C.7.2  permits that the mast spar and main boom spar, when lost or damaged beyond repair, may be replaced with the approval of the race committee.

C.4.2 requires the boat to sail with the mast spar and main boom spar used when the boat was measured for the certificate in use at the event.

The clear implication of C.4.2 is that if the mast spar or main boom spar are replaced then the boat shall be re-measured. If the boat complied with its certificate (and the dimensions on it) no further action is required. If it does not comply with its certificate then the necessary adjustments shall be made to the boat and/or the measurements forms and a new certificate shall be issued.

The 1994 class rule has the same effect.

Question details:

Is it permitted to have a small raised area of deck to house mast partners and a mast ram at the mast point and a small recessed area just aft of that point?


Yes. D.2.3 (d) (1994 CR 6.3.5) allows for a limited amount of transverse deck round, being 1/24th of the beam at any point. The class rules do not place any fore and aft or transverse restrictions on deck camber, only that it shall not exceed the permitted amount.

Question details:

Is the extension fitted to the sails in the photograph to be considered as part of the sail or as a halyard? If the extension is part of the sail then:

  1. Do these sails comply with G.3.2 (b) (1994 CR 6.3.1)?
  2. Where is the head point?
  3. How are the "correct positions" of the battens to be found for clause G.3.3 (1994 CR 6.3.2)?
  4. Do these sails satisfy the requirements of measurement form item 10 (1994 MF item13)?



a      Yes. The upper part of each sail is clearly not separable from the remainder of the sail and is therefore part of the sail. Taking the individual points raised above in turn:
The class rules are open class rules and therefore anything which is not specifically prohibited is permitted. CR G 3.2 (b) requires the mainsail to be trilaterial and bounded by the luff, foot and leech. There is no rule which prohibits a concave leech but hollows shall be bridged as described by ERS H.5.2. For the 1994 class rules the IYRU SMR describe how to handle measurement of a sail with a hollow leech. The sail is not a quadrilateral sail and has the three required edges. Restrictions are placed on the shape and size of the sail elsewhere in the CR and the sail shall comply with those restrictions.

b      The head point is defined in the ERS G.4.2 and is found as the intersection of the luff, extended as necessary, and the line through the highest point of the sail at 90 degrees to the luff. For the 1994 CR the IYRU SMR apply but the effect is the same. The design of the sails referred to does not affect this measurement.

c      The batten position is limited as in G.3.3 (1994 CR 6.3.2). The design of the sails referred to does not affect this measurement.

d      Yes. See (a) above.

Question details:

Can a boat with a certificate in one class also hold a valid certificate in another class?


There is no rule in any of the International One Metre, Marblehead, Ten Rater or A Class class rules which prevents a boat from having a valid certificate for another class.