Just in case you don't know the Flickr address..... with the
SwiftSolo v. 29er shots.
http://flickr.com/photos/loft42/sets/72157594236558557/
Other shots:
http://flickr.com/photos/loft42/
/Al
On Aug 16, 2006, at 1:15 PM, Greg Ryan wrote:
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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