Rule vote: Mainsails and weight reduction delay

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Colin Smith
Posts: 92
Joined: Mon Mar 13, 2006 12:18 pm
Location: Kent, UK

Rule vote: Mainsails and weight reduction delay

Post by Colin Smith » Sun Jan 02, 2011 10:30 am

Hi

We now have the final package together for a vote on the UK and Australian proposals for control of square-head mainsails, and on the Australian proposal to further delay the planned weight reduction - all set out in a pdf file accessible via "world association - class rules - Jan 2011 rule proposals" tabs on the front page, or directly via
http://www.international14.org/index.ph ... &Itemid=37

World Council members will shortly receive an email formally calling the vote

Re the square-head mains, as there are two alternative approaches being proposed, the class is being asked to make a straight choice between them, and to agree we will change the rule based on whichever gets the most votes

Finally, if anyone is reading this at the Aussie nationals,could you please let Stewart Vickery and David Hayter know the document is available - been trying to email them but no luck given they're travelling. Thanks!

Cheers
Colin

Ed Clay
Posts: 27
Joined: Sat Apr 29, 2006 8:12 am

Re: Rule vote: Mainsails and weight reduction delay

Post by Ed Clay » Mon Feb 07, 2011 11:40 pm

In the interests of being open, below is a (rather cumbersome) section from the "start of season letter" that I sent to the UK association. Much of it has been said before but it gives some background and opinions about the ongoing rules vote and might be of interest to those out of the UK.

Cheers

Ed


Rules voting
There are two areas where rule changes are proposed; mainsail measurement and weight. Enclosed are full details of the proposals and a form for you to vote with. Additionally I would like to give a bit of background on the mainsail changes.

Since 1996 the rules have stated that no point of the mainsail can be greater than 7626mm above the sheerline. With a near triangular sail and a fairly straight mast, where the head is clearly the highest point this could be easily policed by marking a band 7626mm above the sheerline on the mast and ensuring the sail was never above this point. Since the development of squarehead mains and modern rigs this has become harder to measure. When sailing, the band on the mast will be usually be less than 7626mm above the sheerline, due to rake and bend of the mast, so a square top sail with a “peak” that is slightly higher than the band on the mast may be legal. But how you measure the position of the “peak” is complex – it depends on cap shroud, cunningham and fore and aft trim amongst other things.

The UK put in a rule proposal in 2009 that solved the problem by “measuring the roach” in the top corner of the sail, increasing the overall allowed sail area accordingly, stating that the head may not be 7626mm above the sheerline and removing restrictions on the height of the rest of the sail. This was voted on at the end of 2009 and reached the 2/3rds majority within the class required to become part of the rules. However in Sydney, at the World Council, three problems came to light; firstly there were some technical errors in the proposed rule that meant it was contradictary, secondly a number of countries felt they had not understood what was being voted on and finally a number of sailmakers suggested that the rule would be harder to design and build sails to. It was therefore decided that the rule change would be put on hold while the inconsistencies were sorted and alternatives proposed.

Unfortunately this process took longer than would have been ideal. However thanks mainly thanks to the hard work of Colin Smith, the World Secretary, we now have two possible approaches, one from the UK – the “measure the roach” approach and one from Australia the “maximum angle” approach.

Both approaches would solve the current issue. They would not increase sail area, would not make current sails illegal, are reasonably simple for the measurers and sailmakers can build sails to them. Where they differ is that under the “maximum angle” approach there would still be significant unmeasured area in the head. This would mean the next generation of sails would look like the current generation in profile; because this unmeasured area would be maximised by having a head angle of 112 degrees (about what most sails have). The advantage of this is that if you currently have a squaretop sail, under this rule it is unlikely that you would feel you had to go out and buy a new main as the head profile was “wrong”. The disadvantage is that sails would be bigger from now on if they have one particular head profile.

Under the “measure the roach” approach there would not be a significant unmeasured area with one particular head profile, so no profile would have an advantage beyond efficiency. Of course, this means there is more of a chance we would see sails that look different in the head; perhaps peaks that project well above the top of the mast, or possibly pinhead mains with area low down. The advantage is that sail design is continually evolving and under this rule we would be able to develop with it, without “paying” with a loss of actual sail area.

It is my view and the view of the majority UK committee that a great strength of the class is being able to both innovate and change. It is what has allowed us to remain at the forefront of dinghy design and sailing for so long and is one of the things that keeps the class so interesting to sail year after year. This is why we are putting forward the “measure the roach” proposal; we believe our proposal addresses the current uncertainty while not restricting future development. Our view is that the “maximum angle” proposal, by leaving an unmeasured area which is maximised by having a 112 degree angle at the head, risks restricting us to what we currently have, rather than allowing the class to develop.

Colin Smith
Posts: 92
Joined: Mon Mar 13, 2006 12:18 pm
Location: Kent, UK

Re: Rule vote: Mainsails and weight reduction delay

Post by Colin Smith » Tue Apr 12, 2011 8:24 pm

VOTE RESULTS NOW OUT

Text of email sent today to World Council members:




Hi again everyone

We now have the results of the vote on the class rules relating to mainsails and weight reduction. The conclusion is that we:
1) WILL change the rule on mainsails, and will adopt the Australian “maximum angle” approach
2) WILL NOT delay the hull weight reduction

Votes were submitted by AUS, CAN, GBR, GER and USA (each of which qualify for 5 votes). AUT and FRA confirmed they would not be voting. JPN are yet to vote, but the votes already cast are enough to decide the outcome. Details of the voting are:

Proposal 1, to change the mainsail rule: all votes cast were in favour, we will therefore change the rule

Proposal 1a and 1b, choice of method to use to control mainsails:
For the UK “measure the roach” approach: GBR (5 votes)
For the AUS “maximum angle “ approach: AUS, CAN, GER, USA (20 votes)
The “maximum angle” approach wins

Proposal 2, to delay the weight reduction:
For: AUS, GER, USA: 15 votes
Against: CAN, GBR: 10 votes
The proposal has not achieved the required two-thirds majority and the weight reduction will therefore proceed as set out in the existing rules (and just to note, even if Japan were to vote, and to vote “against”, their 3 or 4 votes would not be enough to change the outcome)


The rule wording (available via http://www.international14.org/index.ph ... &Itemid=37 ) for the new mainsail rule will be forwarded to ISAF for their approval and the new “maximum angle” will apply to mainsails first measured one month after that approval is obtained (note that sails first measured before then will still have to comply with the existing rules, including the sailplan height limit). I will let you know when we get the ISAF approval

Regards
Colin

aem27
Posts: 81
Joined: Mon Mar 13, 2006 7:14 pm

Re: Rule vote: Mainsails and weight reduction delay

Post by aem27 » Wed Apr 13, 2011 2:11 am

Hi Colin,
So from past experience, when would you expect ISAF to approve the mainsail rule change and therefore do you think that the new rule will apply for Weymouth?
thanks
Archie

aem27
Posts: 81
Joined: Mon Mar 13, 2006 7:14 pm

Re: Rule vote: Mainsails and weight reduction delay

Post by aem27 » Wed Apr 13, 2011 2:49 am

Can you clarify whether the "existing" mainsail rules is the rules from 2008 or do they include the UK proposal voted in at the last worlds?

Colin Smith
Posts: 92
Joined: Mon Mar 13, 2006 12:18 pm
Location: Kent, UK

Re: Rule vote: Mainsails and weight reduction delay

Post by Colin Smith » Wed Apr 13, 2011 9:30 pm

Hi Archie

Based on previous experience, absent any major issues cropping up, we should be able to get the ISAF approval within say 2-4 weeks - so yes the new rule should be in effect for Weymouth. We no longer have to wait for the November conference.

The current rules relating to mainsails are those from 2008 and before, and as published on this website. The 2009 "UK proposal" was put on hold by the World Council and never submitted to ISAF for approval, and hence never became a formal class rule (and the class has now by a large vote decided it prefers an alternative approach anyway).

So basically we have the rules as applied in Sydney, to be replaced by the "maximum angle" approach hopefully in a month or two - and of course the max angle was chosen to match the shape current sails already have anyway (just getting rid of the problem of trying to work out how high the "peak" is)

Hope that helps

Colin

aem27
Posts: 81
Joined: Mon Mar 13, 2006 7:14 pm

Re: Rule vote: Mainsails and weight reduction delay

Post by aem27 » Wed Apr 13, 2011 10:30 pm

Thanks Colin. I was just checking that a 112 head on a bolt upright mast would be approved for Weymouth. It sounds like in all probability that it will be.
(FYI I'm using exactly the same mast).

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