Proposal A: Allowing Carbon Masts
Existing Rules
57-64;
the current mast specific FD
rules 57-64, do not prohibit carbon fibre so do not need to be amended.
Carbon masts are however specifically prohibited by rule 112, which would
therefore have to be changed. The present rule 57 prohibits rotating
masts and rule 60 adequately restricts the mast fore and aft dimension in
order to prevent the development of wing masts.
Change Existing Rule:
112. Expensive Materials
Unusually expensive materials or equipment shall be deemed to be contrary
to the spirit of the class and may be prohibited. Before using such
materials and/or equipment, permission shall be obtained from the General
Committee IFDCO. Composite materials such as those incorporating boron and
other materials of limited availability, are prohibited. However, carbon
fibre (fibres of graphite) and/or aromatic polyamides (aramid) such as
Kevlar (Dupont trade name), shall be permitted as a reinforcing material
in hulls, rudders and centreboards, booms and spinnaker poles, but not on
Masts (including spreaders) and sails.
Note:
Changes to the 2003 FD rules, deletions are struck through, additions are
in italics.
Proposal
B: Transition Strategy
In
order to allow a gradual transition to carbon masts, without a real or
perceived advantage immediately making aluminium masts obsolete, the
present mast weight of 11 kg,
rule 58, will only be reduced to 8.0 kg
if rule 122 is invoked by the Notice of Race and Sailing Instructions for
a regatta series. This would be similar to the implementation of rule
113, i.e. carbon masts would have to comply with the present rule 58, both
weight and CG height, by adding appropriate lead correctors, unless rule
122 is invoked. The minimum height of the mast CG would remain the same.
The situation will be kept under continual review and eventually, in the
light of experience, the mast weight, as specified in rule 58, will be
reduced, whereupon rule 122 will be eliminated.
Add New Rule:
122 Mast Weight
a) In a regatta
series the mast weight, as specified in rule 58, is reduced to 8.0
kg when the notice of race and the sailing instructions contain the
following provisions: "For this regatta series named _____________________
from _______ to _______ the mast weight limitation of rule 58 is reduced
to 8.0 kg."
b) Definition of regatta series as in rule 113.
Proposal C: Loose footed mainsails
The present FD class rule 93
prohibits loose-footed mainsails. The most expensive part of carbon booms
is the sail track. Furthermore the optimum method of attaching the vang
(kicking strap) and main sheet to a carbon boom is via a webbing strap
which passes around and over the carbon tube boom. This requires a cut
away in the track and makes threading the foot boltrope into the track
somewhat difficult. It has therefore been suggested that the Flying
Dutchman class allow loose-footed mainsails.
There is however no ISAF
definition of “loose footed” and the sail track on many booms ends well
short of the gooseneck. It would be possible to have a short section of
track, say 1000 mm
in the centre of the boom, or alternatively lace the foot of the mainsail
to the boom (as in the Optimist) and these alternatives would no doubt
qualify as not being loose footed.
The 505 class is also
considering the adoption of loose footed mainsails and the only reasons
for not doing so are aesthetic and possibly safety (it is possible that
the crew could be caught between the mainsail and the boom in a capsize).
If loose footed mainsails are approved a new rule to prevent the mainsail
extending below the boom will be required. The clew and tack positions
are prescribed by rule 96, although this rule will have to be altered to
specify the top of the boom rather than the foot rope groove. Specifying
the foot median length, i.e. the length from the head point
to the mid foot point, will limit the foot roach so that the sail
does not extend significantly below the boom. The calculated length of
the foot median assuming a straight-line foot is 6449 mm
so allowing for151 mm
of foot shelf gives 6600 mm.
This is an easy number to remember and will not let the foot hang below a
maximum diameter boom. The ERS definition of foot irregularity is “the
maximum distance between the edges of the foot when first the
tack point and then the clew point are superimposed on any part
of the foot.” This ensures that the foot is a fair curve. FD rule 100
already prohibits any batten along the foot of the mainsail.
Change Existing Rules:
93.
A double-luffed or
loose-footed mainsail is prohibited.
96.
The luff of the mainsail when set shall lie between bands
number 2 and number 3. The extension of the foot rope groove in the
top of the boom shall not cross the mast at a lower point than the
upper edge of the respective band number 2. The foot of the mainsail shall
not extend beyond the forward edge of the band on the boom.
Add New Rule:
97.1 The foot median
of the mainsail shall not exceed 6600 mm.
The foot irregularity shall not exceed 50 mm. |
