Another query

Discuss the IOM class rules and interpretations

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Don Case
Posts: 53
Joined: 16 Sep 2008, 05:09

Another query

Post by Don Case » 31 May 2010, 17:04

I have to admitt that this is a little picky but, Section C says that it's rules are in effect while racing. Does this rule not limit the amount of backstay tension(based on boom stiffness)

C.7.5 BOOMS
DIMENSIONS
minimum maximum
Boom spar curvature measured between points on
the top of the spar 10 mm from each end ................................ ......... 3 mm

Should this rule be in Section F?

This won't become a habit
Don
Don Case
Can 271
Vancouver Island B.C.

Andy Stevenson
GBR NCA Officer
Posts: 772
Joined: 15 Sep 2005, 13:08
Location: UK

Re: Another query

Post by Andy Stevenson » 01 Jun 2010, 14:21

Hi Don,

While the rule is in force during an event, measurement isn't taken on the water :)
ERS H.4.3 wrote:No external pressure shall be applied to a spar when measuring unless specifically prescribed.
I read this to mean untesioned.

Cheers
Andy Stevenson
"A little pain never hurt anyone!" Sam, aged 11

Don Case
Posts: 53
Joined: 16 Sep 2008, 05:09

Re: Another query

Post by Don Case » 01 Jun 2010, 17:10

Thanks Andy, I forgot the ERS again. Sometimes it seems like you have to read every rule just to see if it applies to your situation. It would be nice if there was some kind of search engine. I guess there is, it's called the "Rules" section of the IOMICA Forum.
Don
Don Case
Can 271
Vancouver Island B.C.

jandejmo
Posts: 64
Joined: 25 Nov 2003, 07:47

Re: Another query

Post by jandejmo » 02 Jun 2010, 11:37

Hi Don


A few comments:

Class rule C.7.5: "Boom spar curvature measured between points on the top of the spar 10 mm from each end ..."

Class rule A.5.2: "... when a term is printed in “bold” the definition in the ERS applies." So there is a sort of a "search engine" built into the class rules.

ERS F.3.3(b) defines how boom spar curvature shall be measured. The definition ends with: "... when the spar is resting on one side". Clearly that will not be the case when racing.

Boom spar curvature is to regulate "permanent set" and that is why the spar shall be resting on one side with the measurement not influenced by gravity or other forces. ERS H.4.3 also applies as pointed out by Andy Stevenson.

The reason that a boom curvature rule is placed in Section C of class rules is that the curvature may increase over time. Although a boom may bend under load during a race it does not necessarily mean that the boom spar curvature - the permanent set - will increase.

However, I agree that the relation between the class rule and the ERS definition is not obvious. I will raise the issue with the ISAF ERS Working Party and with the chairman of the ISAF Class Rules Sub-committee to see if we can improve on the wordings.

Many thanks for raising the issue!


Best regards

Jan Dejmo

Bruce Andersen
USA NCA Officer
Posts: 764
Joined: 25 Nov 2003, 00:06
Sail number: USA 16
Club: Famous Potatoes Sailing Club
Design: Brit Pop
Location: USA 16

Re: Another query

Post by Bruce Andersen » 02 Jun 2010, 18:19

I wonder if this request shouldn't be sent from IOMICA to RSD rather than from an individual owner straight to ISAF? Organizational schemata only work when used properly.
Bruce Andersen - USA 16
No longer a USA NCA Officer, but can't change my profile!

jandejmo
Posts: 64
Joined: 25 Nov 2003, 07:47

Re: Another query

Post by jandejmo » 02 Jun 2010, 19:25

Hi Bruce

I think the IOM class rules are ok as they are and that an IOMICA request is not needed, but Don Case raised an issue that could help to improve on the ISAF Standard Class Rules and the ISAF Equipment Rules of Sailing.

An issue that I, as chairman of the ISAF ERS Working Party, intend to discuss with the WP to see if we could come up with an amendment for the 2013-2016 ERS. As member of the ISAF Class Rules Sub-committee I also intend to discuss it with the chairman of that committee. If there will be a new ISAF Standard Class Rules wording for a boom spar curvature rule, then IOMICA can use it for the IOM class rules.


Regards

Jan

Don Case
Posts: 53
Joined: 16 Sep 2008, 05:09

Re: Another query

Post by Don Case » 03 Jun 2010, 02:56

Sorry, I didn't mean to start something. This section of the rules says it all

A.5.2 Except where used in headings, when a term is printed in “bold” the definition
in the ERS applies and when a term is printed in “italics” the definition in the
RRS applies.

If I had looked a little deeper and if my memory was a little better(I had heard before that bold meant look in the ERS) I never would have had to ask this question. I think everything is there, sometimes you have to dig deep.
Don
Don Case
Can 271
Vancouver Island B.C.

jandejmo
Posts: 64
Joined: 25 Nov 2003, 07:47

Re: Another query

Post by jandejmo » 03 Jun 2010, 07:31

Hi Don


Your question may well lead to more clear ISAF rules and in turn to easier to understand IOM class rules. Absolutely no reason for you to say "sorry"!


Best regards

Jan

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