IOCA Technical FAQs

This list of the most frequently asked questions is a useful source of instant information.  There is a big difference in requirements for Main Fleet compared to Regatta and Coached Regatta Fleets. Please make sure you are reading the sections that apply to you!

This FAQs document has been compiled in good faith, but no responsibility can be taken for any error and if there is any unintentional conflict with the Class Rules, then the Class Rules will apply.  Please do check for updates to these FAQs which will inevitably occur.

Class Rules are maintained by the Technical Committee of the Optimist Class International Association (IODA).


If you need any help with measurement issues please do not hesitate to contact the IOCA Technical Officer or any Optimist Measurer (see below).  Please feel free to suggest any other FAQs, but in the meantime, the answers to your most common questions are below:

Safety on the water

To race in any of the fleets (Coached Regatta, Regatta, and Main) all Optimists must comply with the safety rules (part of Class Rules). For the Measurers, the safety rules are the priority when they are looking at the boats before/after sailing and during "On the Water Measurement Checks" in Junior and Senior Main Fleet. 

Remember, in the UK, before you race at major events you may be asked to sign a declaration to confirm that your boat complies with all the safety rules.  Any boat later found not to comply may be penalised (Main Fleet only) and will not be allowed to race.  Boats in all fleets (Coached Regatta, Regatta,  and Main Fleets) will not be allowed on the water until the problem is resolved.

In the list of safety rules shown here you will also notice some additional Safety Guidelines which are not Class Rules, but are good practice.  At your home club, if in doubt, please speak to your Flotilla Leader, or you can contact your Regional Rep, a Measurer, or the Technical Officer  who can offer advice.

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Main Fleet 

This section is only for MAIN FLEET.  Ensuring your boat complies with the equipment rules is relatively easy.  If you are new to the class, do ask a Measurer for some help.  Once you have it sorted, then apart from maintenance issues, you will only need to worry about it when you change any of the equipment you use. 

For Main Fleet racing, Optimist Class Rules only permit one hull, sail, sprit, mast, boom, daggerboard or rudder to be used at an event. 

For Main Fleet competitors, all items being used when racing must be measured, have a certificate and all items must appear on the Measurement Record of Equipment Used Form (MRE). Please note that ONLY AN OPTIMIST MEASURER CAN ADD ITEMS TO THIS FORM. If you add items to the MRE form yourself, it would not be possible to verify the initials of the Measurer.  That is an infringement and at major events would attract a penalty. If you were not aware of this and have put the Measurers initials onto the MRE form yourself in the past, don't worry, but you must ask a Measurer to re-do this for you before the next event.

There are a number of active Measurers in the UK, there are usually a few at major events and others are available in all regions around the country.  Please contact them to help you comply with the equipment rules.


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Measurers

Optimist Measurers are individuals who have been trained by both the RYA Technical Department as Sail Measurers (World Sailing Sail Measurer qualification) and by IOCA as an Optimist measurers.  Measurers are mostly parent volunteers, just like all other helpers at events and in IOCA.  

There are three types of Measurer:

Measurers must renew their World Sailing Sail Measurer qualification every 4 years.

You will notice on the list of Optimist Measurers below that most are Ms.  This is because (since 1995) nearly all new boats are delivered pre-measured from a licensed Optimist builder.  Fs are still needed, however, e.g. at major IODA events, or when a new builder is licensed and, most often, to re-weigh boats when they have lost their Registration and Measurement Book.

The list of Measurers is often updated, so please re-check when you need a measurer - someone nearer to your club may have been recently added.

Measurers are freely available to offer advice, but Measurers are entitled and encouraged by the RYA to charge for actually measuring equipment plus any travel expenses.  Measurers have to pay to qualify/renew their qualification, as well as buy and maintain their own measuring equipment. If you have a sail measured, you must pay at least for the RYA sticker.  If you have many items to measure and travel is involved, it is very sensible to check what the cost will be before making an arrangement.  


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BOAT DOCUMENTS/MEASUREMENT CERTIFICATES

I want to race in Regatta/Coached Regatta Fleet - which documents do I need?

To race in Regatta or Coached Regatta Fleets boats must be Optimist dinghies which comply with the spirit of the rules.  No formal measurement documentation is required to race - apart from written evidence of a buoyancy test within the last 12 months (see item 2.3 in the main FAQ list above).

But please note:

- At events you must sign a declaration to confirm that you comply with all safety measures (which apply to Optimists in all fleets). See the checklist here. If any boats are later found not to comply with the list of safety measures, they are not permitted to go on the water at events - for obvious reasons!  Please make sure you check the safety rules and that your boat complies with all items on the list.

If in doubt, just consult a Measurer or your Flotilla Leader!

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I want to race in Main Fleet - which documents do I need?

Boats in Main Fleet must have a full set of Measurement documents which confirm that:

This ensures that all boats can race as equals on the water and the skill of the sailor is paramount.  In the past there have been some really amazing attempts to circumvent rules and give a sailor an unfair advantage over their competitors, so it is really important that we all treat the Class Rules with respect.

You must bring your boat's measurement documents along to major events in case a Measurer wishes to check them.

Also, of course, at major events Measurers carry out spot checks on the water and before/after sailing, so it's important to get your boat's documents in order.  

Getting used to maintaining your boat's documents is excellent preparation for sailing in other classes in the future and is part of the education you receive from sailing Optimists.

So, recent UK boats (since 1995) should have an IODA (International Optimist Dinghy Association) Registration and Measurement Book which contains:

There is one slight exception to the above list.  If a boat's Measurement book has been lost and a new one issued by IODA, the contents of the Registration and Measurement Book is different. The two page blue Hull Measurement form is replaced with a  single blue sheet which must show the signature of the Full Measurer (or RYA Technical) who carried out the re-weighing (which must be done when a replacement Registration and Measurement book is issued).

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What information goes on the RYA Certificate? 

The RYA certificate should show the name of the boat's owner.  It is strongly recommended that you use your family name when applying for an RYA certificate, e.g. "The Welfare Family". That means you can hand the boat down to younger siblings without having to get another certificate issued - saves time and money! 

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Annual Buoyancy Endorsement - how can I get it done? 

When your boat's Annual Buoyancy Test is due for renewal, it is very easy to get this done.  Pages 13 and 14 of the class rules describes how to carry out the test.  Your Flotilla Leader, or any other responsible club official can carry out the test for you.   Of course, any Measurer can carry out the test too, but unless you are lucky enough to have one at your club, it's much easier to ask someone on your sailing club's committee.  The successfully completed buoyancy test should be recorded in one of the following places:

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I have lost all my boat's documents - what should I do?

When your boat has been measured but you have lost all your documents - don't worry you are not the only one - it happens quite regularly!

If the documents really are lost, then the first step is to contact IODA (International Optimist Dinghy Association) and purchase a new Measurement Book (around USD60.00).  

Unfortunately you will need to have the boat re-weighed, either by a Full Measurer or by RYA Technical (unless RYA technical have a previous measurement certificate on record).  You will need to hand the Measurer or RYA technical the light blue Replacement Hull Measurement Form (received along with your new Registration and Measurement Book from IODA) to be signed once the boat has been re-weighed.

The RYA (technical@rya.org.uk) will then issue a new RYA Certificate on sight of the new Measurement Book and completed Replacement Hull Measurement Form.  If RYA Technical re-weighed your boat, you will then need an Optimist Measurer to help you reassemble the documents.  Only those Measurers who are approved by the RYA and appear on the list here are eligible to measure Optimist Equipment. Be prepared for the possibility that the Measurer will have to re-measure all items of equipment and sails to re-certify them.  

  

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I have lost all/some of my documents - can I race in Main Fleet?

Without a valid Measurement Certificate, Class Rules state that a boat is not permitted to take part in Main Fleet races. All is not lost, however, but please do read right to the end of the following section:

  1. Major Events If the Technical Officer (TO) or event Chief Measurer considers it to be a genuine case then there is a discretionary procedure to allow a boat to sail under what is known as an Infringement Notice.  To do this, the TO will require the serial numbers of any items which do not have a certificate.  

In this case the sailor is allowed to participate in the event and the result is marked as Provisional.  The sailor then has 30 days to get their Measurement infringement corrected and provide the TO with the evidence.  Assuming everything is satisfactory, the TO will then inform IOCA that the result is no longer provisional.  

If, after 30 days, the TO has not received evidence that the infringement has been rectified then, unfortunately, the boat's result in the event will not stand which could impact a sailor's eligibility for training squads/teams.

Please contact the Technical Officer as soon as you realise that you may have a problem.  It is best dealt with in advance of an event.  Please note, however, that the Infringement Notice is a last resort and sailors must demonstrate that they have done everything possible to avoid the situation.

2. Team Selections At the Selections event when a lot is at stake with results for team places being fought out, then the Infringement Notice procedure is not available.  

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I bought my boat without any documents - can I race?

1. If the boat is an Optimist dinghy then, as long as it complies with the spirit of the rules and complies with all the compulsory safety measures in place then it may compete in Regatta  Fleet races.

2. If you wish to enter the boat for Main Fleet racing then you will need to rebuild the boat's documents. The procedure is below:

a) Does the boat have a blue and white ISAF plaque sticker inside the hull?  If so, then see above "I have lost all my boat's documents". 

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b) If there is no ISAF plaque in the boat, then it is most likely that it has never been measured.  But if it has a number moulded into the hull then it could be worth checking with the RYA/IODA/IOCA Technical Officer.  They should be able to give you some info.  

If there is no ISAF/World Sailing plaque and no moulded serial number then assuming it is actually an Optimist dinghy (you can consult a measurer for advice), probably the best way forward is to use the boat for training and Regatta/ Coached Regatta Fleet racing only.  Assuming it is an older boat, getting it measured from scratch may be disproportionately costly (it takes a while to complete this work) and the cost of this would probably be better spent going towards a new boat.  

The reality is that if it is a post-1995 boat then it must have an ISAF plaque applied by the builder or it is not compliant with Class Rules.  All boats supplied by a Licensed Builder must by definition comply with Class Rules and have an ISAF plaque attached.  If it was built post 1995 and doesn't have a blue plaque then it is probably a prototype from a new builder and there is something invisible wrong with it - e.g thickness of laminate etc - and it was sold by the factory as a training boat. 

If the boat has an IYRU plaque but no certificate then it would not comply with the current rules in any case.  

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Can I build an Optimist myself in glass fibre? 

You can build a wooden Optimist but building a GRP boat yourself is more complicated.  Since the rule change in 1995, glass fibre Optimists can only be built by IODA licensed manufacturers (CR 2.7.3.1).  You could build an Optimist in glass fibre at home, but to do so you would have to become a licensed manufacturer yourself.  This would be a lengthy business involving the production of several prototype hulls for IODA measurers to inspect and cut up, etc. along with all the associated costs.

Obviously, the reason for this is to ensure that all Optimists are built the same which means that buyers in any country can be confident their locally produced Optimist is as good as any other.  This saves the cost and hassle of shipping boats all over the world as people seek to buy what is perceived to be the fastest hull.

However, the news is not all bad… you can build a wooden Optimist and the plans are available from IODA. The tolerances are very tight, but getting it spot on could be part of the fun.  Once built, the boat would have to be measured by a Full Measurer (FM) and you would have to budget for the measurement process.  

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NEW EQUIPMENT

I have bought a new, unmeasured sail/piece of equipment - can I use it this weekend at a major regatta? 

The answer to this is yes, but please read on...

Unless you make an arrangement in advance it is not advisable to appear at Registration before one of the major regattas with the new sail, spar or foil and expect that a Measurer will be able to carry out measurement for you before the first race that morning.  This is particularly the case for weekend events when it is often very rushed on the Saturday morning.  

If you are in this position then the best thing to do is:

a) Contact your local Optimist Measurer and have the job done during the days before the regatta (this is the low stress option)

b) Contact an Optimist Measurer who will be at the event and make an arrangement to meet them at an agreed time in the morning before you register to get the item measured. Measurers are listed below and are the only ones eligible to measure Optimist equipment, (this is a medium stress option).  

c) Contact the Technical Officer (TO) to see if they can help you find a Measurer to help you on the Saturday morning.

In some circumstances, if there is a genuine problem, then the TO may be able to assist by issuing an Infringement Notice to enable you to take part in the racing pending measurement of the new item.  Please contact the TO as soon as you know there may be a problem.

d) There will usually be Measurers at Registration who may help with entering items onto the MRE form and other advice, but if it's busy then there may not be time, especially for items like sail measurement. (this is the high stress option!).

It is worth asking the equipment supplier if they will supply the item pre-measured.

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I have bought a new sail - what do I have to do before racing with it?

Whatever the status of your new sail (measured or otherwise) you will need an IOCA Measurer, at the very least to add the sail to your Measurement Record of Equipment Used (MRE) form. You cannot add a pre-measured sail to the MRE yourself - it must be done by a Measurer.

RYA Approved Measurers are listed below. Alternatively you can use an RYA Sail Measurer. If you use an RYA Sail Measurer please see c) below.

New Sails can be:

a) Completely unmeasured without numbers attached.  You need to buy and attach numbers and national letters.  Before you stick them to the sail, consult rule 6.5 in the Rules (there is also a diagram shown on the Sail Plan).   Remember, numbers and national letters must be the same colour.  Then contact a Measurer (see above) to have the sail and numbers measured and added to your MRE form.  

b) Sail measured, sail numbers and national letters are attached but not measured. In this case you need a Measurer to certify the numbers and add the sail to your MRE form.

c) Sail and numbers already measured. In this case you just need a Measurer to add the sail to your MRE form.  You cannot add this sail to the form yourself.  If you do, then during an equipment check the signed initials could not be verified which would be an infringement liable to penalty.

Can I use a different sailmaker from the usual ones - or I want to make my own sail - can I do that?

Yes, as long as the sail is measured it can be used for racing. The sail must have an IODA label/ buttons.  They can be purchased from IODA.  Contact info@optiworld.org

Once the sail has been measured,  if it is altered it must be re-measured.  Measurers keep an eye out for tell-tale marks which indicate a change of seam position. 

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Can I fit a second ratchet block to the boom - or can I attach my single ratchet block to the boom? 

Only one ratchet block is allowed - and it must be attached to the floor of the hull.  If you have a second ratchet block or have your block attached to the boom rather than the hull then you are liable to be protested or subject to a penalty. Source: IODA 01/05/2016


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Sail Numbers - must they all be same colour and font? 

Sail number and country letters must all be the same colour (although the Optimist logo can be a different colour). There is no rule about mixing fonts as long as eligibility is not compromised.  Check permissible fonts in this document

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Am I allowed to use an electronic compass?

A simple digital compass with no recording or memory is permitted, It may contain a timing function.

Class Rule 3.2.6.1 (d) A compass and associated fittings, which shall all be removable for weighing the hull. A compass may include a timing device. An electronic timing device is permitted. No electronic devices other than those required or permitted by an Organizing Authority and/ or IODA in the Notice of Race and/or Sailing Instructions, shall be permitted on board when racing.

https://www.optiworld.org/index.php/default/news/new/text/the-use-of-electronic-compasses 


In April 2024 we were informed that the IODA technical committee have considered Raymarine’s Micro compass. They have determined that  the Raymarine Micro Compass has a memory and therefore these compasses are not permitted under the class rules.

To comply with class rules, only a simple digital compass with no recording or memory is permitted. Compasses with a memory such as Raymarine Micro compasses are not permitted.


Can I use a gooseneck level wind indicator like a Little Hawk Mk2? 

Unfortunately not - wind indicators must be mounted at the top of the mast.

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SECONDHAND EQUIPMENT

I have bought a secondhand sail/piece of equipment - can I race with it straight away?

You certainly can - as long as it complies with class rules.

Please note that pre-1995 foils although 'grandfathered' on the original boat, cannot be transferred to a new boat.

a) If the equipment is already measured when you buy it please ensure that the previous owner gives you the Measurement Certificate for the item you are buying (found inside the Registration & Measurement Book).

The individual equipment certificates take the format of: a green A4 form Sails, a yellow/gold cut-out form for Spars, a pink cut-out form for Foils. For spars and foils use scissors to remove the one that goes with the item you are buying.  NOTE: very often, the certificates are white rather than coloured as above.  

Please append a spar or foil cut-out form with glue or Sellotape to the corresponding page in your own Registration & Measurement Book (to avoid it getting lost).

You will then need a Measurer to add the item to the boat's Measurement Record of Equipment Used (MRE) form and ensure that your boat's national letters and sail number are marked on the item. Also, for sails, the RYA Measurement Certificate should be updated with the information relating to the new sail transferred.

Please note, you cannot add any items to the MRE yourself - it must be done by a Measurer.

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b) If the item you are buying is secondhand but not measured - caveat emptor!  Before you pay, you need to be pretty sure that it will measure OK, otherwise it will be useless except for training.  Be careful, particularly when buying secondhand foils which might be pre-95 type (no longer permitted on post-2005 boats). Best to check with a Measurer if you are in doubt about anything.  But of course, the Measurer cannot confirm that the item will meet the requirements of the rules until they have actually measured it for themselves.

You will then need the Measurer  to add the item to your Measurement Record of Equipment Used form. You cannot add a pre-measured sail or other item of equipment to the MRE yourself - it must be done by a Measurer.

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I have bought a secondhand boat - what do I do now? 

You need to change the owner's name on the RYA Certificate.  It may be best to register a boat to the family rather than an individual sailor, so you can pass a boat down the line to younger siblings. Details are at measurement-certificates (rya.org.uk) You should also change the name in the front of the Registration and Measurement Book. You will find space for second and subsequent owners to add their details on the back of the Builder's Declaration/Building Fee Receipt sheet. 

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MEASUREMENT AT EVENTS

What measurements take place at events? 

For Regatta and Coached Regatta Fleet measurement, please see section 2.1 above.

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For Main Fleet, in order to ensure that the skill of the sailor is paramount and all equipment used by the sailors conforms with the class rules, there are measurement checks at major events.

1. Measurement procedure at major UK Events (excluding Team Selection Trials)

This includes National Championships and Ranking Events.  The info below is a general guide and you must check the NOR/SIs for each event to find out exactly what measurement activity will take place.

i) At registration sailors must: 

ii) Checks ashore before racing

Measurers will usually walk around the fleet before launching, looking out for any obvious infringements of class rules.  

Please don't be nervous about this!

The Measurers are doing this to help competitors comply with rules (especially the Safety rules) so that sailors can avoid any problems if they are called for an On the Water Measurement Check (see below).   If you see a Measurer helping a nearby boat, why not go over and ask them to come and have a look at your boat as well?  It's a good time to ask any questions or to arrange to meet a Measurer for a chat after racing about anything you don't understand.  

iii) On the Water Measurement Checks after each race

At major events including the National Championships and Ranking Events the Race Committee is likely to require measurement checks on the water after each race. The objective of these inspections is to check for compliance with the Class Rules, so that races are fair and safe for everyone.

Inspections are primarily on the top group of boats.  The finishing positions of the boats to be inspected are decided before the racing starts.  Sometimes boats finishing further down the fleet may be checked.  Also, if the Measurer sees a boat which appears to be breaking any equipment rule, then that boat may be called for inspection irrespective of their finishing position.

If you are one of the boats to be measured, then you will be hailed as soon as you have completed the race - when you finish a race always look out for the boat flying the yellow flag labelled "Measurer".  If hailed, you must proceed immediately to that boat and follow instructions you are given - usually, if there are no problems, the whole process takes less than a minute.

If your boat does not comply then a penalty may be applied to your score - check the NOR/SIs at each event for details of this.

What On the Water Measurers will check:

OWMCs are limited to important safety and rigging issues, you can find a copy of a Measurer's Check Sheet here.  At IOCA events the Measurers will also usually record your sail button serial number.  This is checked ashore after racing against the number you entered on your registration form

Usually the most common infringements are:

Apart from safety rules, these infringements could have a beneficial effect on boat speed which is why Measurers have a problem with boats not complying!

iv) Spot checks ashore after racing

After racing, boats in certain finishing positions (determined in advance), plus any boats which the Measurer has any reason to think are not be compliant, may be called to present their boat and measurement documents for inspection ashore.  At this check, the Measurer is likely to inspect the following:

2. Team Selection Trials

The top 80 or so Optimist sailors (selected from rankings) are invited to take part in the Selections Trials. 

The Race Committee will expect all boats to be fully compliant with all Class Rules.    The measurement regime at the Team Selections is accordingly tightened up to reflect the importance of the event.

Competitors must declare the serial number of the items they are going to use on the online event measurement form. The equipment may be checked on or off the water.  Sails may be stamped to ensure that only the sail registered for use at the event is used.

If you have qualified for the Selections, please carefully check that all your boat's equipment is measured and certified and that the equipment serial numbers shown on your Measurement Record of Equipment Used (MRE) form match those on the equipment itself.  

Please consult a Measurer if you are in doubt about anything.

Please ensure that you carefully check the Selections NOR/SIs for details of measurement activity.

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What are Penalties given on the water? 

For Main Fleet, at most IOCA UK major events and at all major international events there are measurers on the water who will carry out checks on boats finishing in pre-determined positions after each race.

The below information is intended only as a guide.  You MUST check the event website, measurement instructions, NOR and SIs for each regatta you attend to ensure you know what the measurement regime will be.

At major international events there are penalties for non-compliance with Class Rules.   To give you an idea, see the 2022 IODA North American Champs penalties here.

These penalties are applied without any warning - although of course you could attempt an appeal.

For IOCA UK events, the situation is slightly different.  The emphasis is on education and so for that reason the penalties themselves are not so harsh and also there is usually a warning given for a first offence.  

To illustrate - following Race 1 you are called for Measurement and it turns out that you are out of bands.  In this case you will be given a warning which will be noted by the measurer.  If you are picked up again in Race 2 and this time your whistle is not tied to your buoyancy aid you will be given a further warning (as it is a different offence).  If after Race 3 you are unlucky enough to be measured yet again and found to be out of bands, you will be penalised (as it is a second offence). 

If you are found to be consistently not complying with the equipment rules, the Race Committee is likely to protest you on the assumption that you are deliberately attempting to gain advantage by circumventing rules.

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ADVERTISING

I've got a sponsor!  Where can I put their logos?

Before making any deal with your sponsor, please look at ISAF Regulation 20  - Advertising Code.  It is your responsibility to check the latest version on the World Sailing site to ensure that you will comply with World Sailing and Class Rules.  

CR 2.8 states that advertising is restricted to temporary stickers attached to the hull but please also see item below for further info.

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Can I advertise a sponsor on my clothing? 

As per WS Regulation 20 Appendix 1, you can wear a bib with advertising on it unless you are issued a bib by the Organising Authority (OA), in which case that must go over the top of your advertising.  

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MEASURERS


NAME EMAIL FULL/MAINTENANCE AREA

Trevor Jenkins Trev@wirralmarine.com Maintenance North West

Chris Pank chris@panks.co.uk Maintenance East of England

David Baddeley David_baddeley@hotmail.com Full Thames Valley

Nick Holley Nick.holley@btinternet.com Maintenance South West

Thomas Jones taj360@gmail.com Maintenance South East

Clare Sargent Clareruthsargent@btinternet.com Full South Coast

Chris Henderson cris6nmj@googlemail.com Maintenance East of England

Will Welfare will.welfare@gmail.com Full North West

Ian Scott ianmbscott@btinternet.com Maintenance North West

Adam Cowley adam@box-yacht.com Full North West

Ben Shelley ben_shelley@hotmail.com Full Scotland

David Chivers david@sarvid.com Full East of England

Chris Fuller crfuller@btinternet.com Maintenance South

Carren Bell carren@lagans.org.uk Maintenance North West


USEFUL DOCUMENTS

This FAQ page is compiled by technical@optimist.org.uk please feel free to suggest new FAQs. 

Last update 28 April 2024.  

Thanks to past TOs for passing on their knowledge.