Hi Steve, I didn't get a reply from you regarding the mast data I sent or the
Australian Member National Authority and ISSA Council delegate. In the mean
time, and possibly of interest, we have been measuring the 29er over here. As
you know the 29er hull is very close in size and weight and shape to the Swift.
The 29er jib IS the same size as ours, but our mast and main is bigger. The
29er XX carbon mast is said to have the same (or very close) overall mast
dimensions as ours, of course the standing rig will be different so I have been
waiting to get hands on the 29erXX rig to check the dimensions and compare the
Pride/Bethwaite designed spinns. Maybe this is something you can work out. In
any case it might be a simple option, but not necessarily any cheaper, IF it is
sized close enough. Worth looking at anyway? (Some picture comparisons are up
on Al's flicker site).
On advisory rulings in general;
In general, if anyone is looking for benediction on what they consider a
variation that might need prior approval of the technical committee (whose
authority comes from part A 3.8 and 3.9 Management Rule and Part B Rules
4.4-Restricted Features and Materials and 4.5-Advisory Rulings, see below) then
you should make a detailed drawing with explanations and email or send it to
the Class Secretary. The Secretary will pass the drawings on to the chairman
of the technical committee (appointed each year by the Class Council or EC) to
examine it correspond with you about it and finally recommend action to the EC
which will issue an advisory ruling to you through the chairman of the TC (who
will also direct the class measurers in the application of the advisory
ruling). If you or the EC and or council consider Class Rules need to be
changed to accommodate such a design variation, then a proposal (seconded by
two other owners) should be submitted to the Secretary before March in the year
the member owners would vote on the issue. The EC will arrange a (email/web)
vote prior to the AGM and a simple 2/3 majority of votes received from eligible
owners will accept the proposal. It will normally come into effect at the AGM
which is held after the Gold Championships (next in the northern part of NA
around the US mid summer 2007 timeframe, and yes, this year competing boats
WILL be measured).
4.4 Restricted Features and Materials
To ensure the objects of the class are not prejudiced, where a person proposes
to build a Swift Solo which:
1. Incorporates a design feature of the hull not expressly specified in the
template drawings plans and construction manual; or (.) not currently in use in
Swift Solos already racing, the owner must seek the approval of the Technical
Committee of the ISSA before constructing the Swift Solo.
4.5 Advisory Rulings.
Builders intending to construct boats for measurement under these Rules are
advised to submit details to the ISSA, or its approved representative, of any
feature which may impinge upon the spirit or letter of these rules. Upon
submission of full drawings and explanations, a confidential advisory ruling
may be obtained without obligation.
On a more specific note regarding your prod receiver design,
The guidelines our Vice President Robert Harper foreshadowed are reasonable I
think. Keeping in mind when designing the pole spar that the pole and the
forestay fitting are "included" in both the swing test and the weight test, so
I don't see a strong incentive to make them much lighter, and therefore in real
need of receiving tube support out in front of the boat. No poles have broken
in the class so far. However, I don't think the feeling in the class is to
stand in the way of improvements in rig, especially if you can make a case for
reliability and efficiency issues. Moreover, I don't think the class would be
in favor of maintaining the status quo simply to provide a convenient lifting
or pivot point for the boat, but there would likely be a negative response from
the TC and current EC to a proposal for penetrating the deck and flotation
space at the bow in any way. Without preempting the TC's or EC's decision on
the matter, the relevant rule might be
5.12.3b Hull Dimensions
Length overall shall be measured with the hull's designed waterline
horizontal, between perpendiculars at the AMP and the forward most protrusion
of the hull. This measurement shall be a minimum of 4.363m (171 3/4 inches) and
a maximum of 4.375m (172 1/4 inches).
So the length of the hull and protrusions is set at 14.35 feet. It could be
possible that if you make a good argument that the prod is a part of a
"forestay fitting" rather than a part of the hull (and this may hinge on
attachment method) then rule 5.12.3b might not apply, as a fitting might not be
considered as part of the hull. The usual rules for position of forestay
attachment etc will apply to that fitting. The mechanical problem I see with
that is that the pole is a long lever - on the bolts of the forestay fitting.
It better be attached aft and securely to the deck.
Alternatively you might make the outermost part of the receiving tube at
position 4.375m and extend the structure inwards, attached to the deck. As the
designers building guidelines now stand, the pole guide and forestay fitting
complex is not all that far in front of the pole collar. A receiving tube
extending back that far or most of the way might accomplish the objective? The
attachment of the pole is not a controlled measurement point, per se, in so far
as it does not frustrate the rules or alter the nature of the design. Hence
the reason for inclusion of rule B.4.5
Good sailing..
Greg Ryan
ISSA President.
----- Original Message -----
From: Steve Nichols
To: Swiftsolo
Sent: Wednesday, August 16, 2006 3:32 AM
Subject: Class Rules Opinions please
Guys,
I've been talking to Clive at CST re masts for Swifts over here. We are also
going to get the other spars from him ie spinnaker pole and boom.
Clive is very keen to change our pole launching system so the spin pole
retracts into a receiving sleeve a la I14 style. This has a couple of
advantages - smoother launches and no issues with point loads on the pole. The
question I have is that reading the class rules it specifies that the pole must
retract to 700mm of the stem. We would like the receiving pole to go out to
this dimension - this further minimises any bending that may occur.
What are peoples opinions? Is this breaching the rules or not?
Also what actual length are the poles in use and diameter?
Cheers,
Steve
nb the 14s allow this but it is specifically catered for in their rules
Class rule extract
a. The Spinnaker Pole shall be retractable to within 700mm (27 5/8 inches) of
the stem. The length from the AMP to the outer most extremity of the spar, when
the spar is fully extended shall not exceed 6.095m (240 inches).
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