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A-Cat Class Rule rewrite - UPDATED

A-Cat Class Rule rewrite - UPDATED

The Technical Committee has updated the rule rewrite, based on some of the questions and comments received since first published. There are a few minor changes, and a few with a little bigger impact. Here's a list of the changed rules:

  • C5.1 (b) – parts of the rule have been deleted.
  • C5.1 (c) – added.
  • C5.1 (d) – added.

Our current rules does not limit the usage of compasses, GPS or other devices, so therefore the rewrite also shouldn’t do it.

 

  • D3 – ISAF added.
  • D5.2 – Hull replaced by Boat in the last sentence.
  • D5.4 – Back beam added.

Based on feedback from members and reviewers.

 

  • E2 – the word “rudder” is changed to bold.
  • E5 – the word “rudder” is changed to bold.

To make sure Rudder refers to ERS definitions.

 

  • H1(f) – section added.
  • H1(h) – removed. (With f added, the former g has become h).
 

Please read the introduction to the Rule rewrite here.

The updated rule rewrite can be found here. All changes (except for deleted text) is highlighted in red. Please read this in conjunction with the below comments.

Questions to the rule rewrite can be sent to technical@a-cat.org, and the Technical Committee will try to answer them within a few days, and we will maintain the FAQ below, as questions come in.

FAQ

C.4 . Equipment items. Paterning the sailors what they have to wear?
C.4.3 There is nothing written how this is measured
C.5.1 I see in the rule rewrite that GPS are not listed and as this in the close rule section this means they are not allowed in any event, how can this happen?

Changed in update.

D.3 I don't think it is really important but some may understand this rule that they have to change theirs ISAF plaque for the new WS one. Especially that they look different.

Changed in update.

D.4 I think this complete rule can go away or say maintenance is not limited in A class
D.5.1 I have retrofitted some cassette rudders onto my DNA, there was some supplied reinforcing plates that attach to the outside stern of the hulls that the gudgeons bolt through, is this ok?
D.5.4 Balance weight at the front beam?

Changed in update.

D.5.4 It does not seem logical to restrict corrector weights positioning.

Changed in update.

E.4 ...or be capable of being fully retractable into the hull. Does this mean the daggerboards could be retracted into a solid tramp between the two hulls like the DNA F1 tramp?
E.5 (a) ...The temporary moving of rudder blades outside the 30 cm limit for the clearing of debris is allowed. I think that the rules should also specify that in some positions rudders may exceed 2.3m as it is the case when strongly tilted.
E.5 (a) This rule outlaws all rudders that rotate into position after lauching as they exceed 30cm (exploder rudders).
E.5 (a) Does this allow sailing with one rudder tilted up in light airs? clearly the raised blade would be >30 cm aft of the LOA.
F.1.2 The boom is also recognized as a spar, so it seems that the boom shall also be signed during the certification process. It should be "mast spar" not "spar" as in ERS.
G2.1(c). Anti fouling boom sleeves?
H.1(h). Is this a new rule?

C4.
Q: Equipment items. Paterning the sailors what they have to wear. Has nothing to do in the rules of the class, but if, then in the rules of World Sailing. If race management/SI prescribes lifejackets or other equipment, there is a flag or generally responsible for the organizer.
A: This rule comes under Part II and relates to both crew & boat under the World Sailing template. C.4.1 is mandatory in regards lifejackets and it’s inclusion gives life jacket standards required. RRS 40 covers there use. C.4.2 a,b,c is optional but may be invoked by Notice of Race or Sailing Instructions, again its inclusion is to assist race committees or organizing authorities with standards if they decide to utilize.


C.4.3.
Q: There is nothing written how this is measured?
A: We also race under the Racing Rules of Sailing and Rule 43.1 and Appendix H covers the weighing procedure. We have specified the maximum weight of 10 kilograms on advice of World Sailing to cover future developments in protective gear.


C.5.1
Q: Our current class rules make no mention of the use of GPS units, so they are allowed. They are not allowed under our championship rules Rule 16 which applies to the Worlds & Europeans. I now see in the rule rewrite under C.5.1 that they are not listed and as this in the close rule section this means they are not allowed in any event, how can this happen.
A: Good pickup and one we have missed. It was never the intention to change any rules simply to remove all the interpretations, fix up any abnormalities and bring into the World Sailing format. The transfer of some of our rules into the closed class rule format has been a difficult task at times. We will amend C.5.1 to include.
Please note the championship rules for the worlds and Europeans will still forbid their use under the present wording and event NORs could do also.


D.3
Q: I don't think it is really important but some may understand this rule that they have to change theirs ISAF plaque for the new WS one. Especially that they look different?
A: Good point, we will change D.3 to read:
From January 2010, all new boats shall have a World Sailing/ ISAF plaque affixed to the transom.


D.4
Q: I think this complete rule can go away or say maintenance is not limited in A class?
A: It was always difficult trying to keep within the World Sailing Template. Section D is under open class rules and this wording really allows anything, which does not change the shape of the hulls. Anything other than this does need to be looked at for recertification.


D.5.1
Q:In D.5.1 it states length of boat excluding rudder hangings shall be not more than 5.49m. I have retrofitted some cassette rudders onto my DNA, there was some supplied reinforcing plates that attach to the outside stern of the hulls that the gudgeons bolt through, is this ok?
A:This is a good question and one that confuses a lot of people. The rule has not changed on this. The class has no standard rudder hanging/gudgeon shape and basically anything is allowed provided that if they can be adjusted in any way the rudder assembly in a fully down position can be no further than 30 cm from the stern of the boat at the maximum adjustment and not form any type of extension of the hull length by any form of fairing. If the stated reinforcement plate is bonded to hull it then becomes part of the hull and is included the 5.49m measurements. If it is removable along with the rest of the rudder hanging/gudgeon then it is not. Any retrofitting of boats that could change measurements must be remeasured and new certificate issued or the current certificate amended to verify.


D.5.4
Q: Balance weight at the front beam. Is definitely an extension of the class rule, which requires the approval of the entire class and thus so far not to be interpreted from the rules.
A:The class rules have gone from a 2 page document to 12 pages under the World Sailing guidelines and this was the whole purpose of the exercise to bring us into line with all the other International classes. There are a number of small changes and one is designating the placement of corrector weights. We have simply specified a position if required, nothing else. This document will go before the entire class for approval in terms of our constitution, nothing will change until this occurs.

(Back beam has been added in rule rewrite update)


D.5.4
Q: In a development class like the A were mods are allowed by rule D.4, it does not seem logical to restrict corrector weights positioning. Therefore in my opinion D.5.4 should be removed. Moreover, a catamaran does not necessarily have to have front and aft beams.
A: The rule rewrite invokes the use of the ERS and ERS Rule C.6.3 (v) states that a corrector weight should be installed in accordance with class rules hence it was necessary to state a position. The front beam was deemed the most logical for this purpose. You state that a catamaran does not necessarily have to have a front and back beam. However to satisfy the definition of a catamaran D.2 (a) there needs to be something connecting each of the two hulls together and the word beam I believe is sufficient to cover this.

(Back beam has been added in rule rewrite update)


E.4
Q: ...or be capable of being fully retractable into the hull. Does this mean the daggerboards could be retracted into a solid tramp between the two hulls like the DNA F1 tramp?
A: This is the same wording as in our current rules. We have done our best not to change anything if not necessary. It really doesn't matter where the daggerboards go when retracting them, as long as the comply with the maximum beam of 2,3 m over the waterline and if they are capable of being fully retracted. Originally this wording was put in to allow Tornado style swing up daggerboards.


E.5 (a)
Q: The temporary moving of rudder blades outside the 30 cm limit for the clearing of debris is allowed. I think that the rules should also specify that in some positions rudders may exceed 2.3m as it is the case when strongly tilted?
A: The rule is very clear and clarifies the decision made by World Sailing for the Medemblik Worlds (Refer IACA website news 19/2/2016)). At measurement a rudder assembly measured parallel to the hull centreplane in a fully down position must fit within a 30 cm distance from the aftermost point of the hull. If rudder hangings/gudgeons had the facility to allow adjustment then measurement would be taken in the maximum adjusted position.

Q:This rule outlaws all rudders that rotate into position after lauching as they exceed 30cm (exploder rudders). There should be an allowance like "The temporary moving of rudder blades outside the 30cm limit for the clearing of debris and launching/retrieving is allowed."?
A: The rules apply while racing. What ever you do to launch your boat doesn't matter. In our current rules L rudders can't be retracted higher than having the Horizontal part 153mm from the bottom of the hull. That's often managed with a "black band". But nothing stopping you from pulling it all the way up while launching or retrieving.

Q: Does this allow sailing with one rudder tilted up in light airs? clearly the raised blade would be >30 cm aft of the LOA.? The intent of the rule is to prevent making "longer" boats with rudder gantries or similar devices.
A: That's correct, the intent of the interpretation when put in place was to cover what you state however the use of one simple sentence put in good faith “As a guide the Technical Committee defines that the rudder appendage and rudder in a fully down position shall fit within 5.79m from the perpendicular extremity of the hull“ put our measurers in a position of having to make a judgment call everytime they had an issue with this. For this reason and given the change from pre race measurement to post race measurement at the Medemblik Worlds, World Sailing was requested to give a ruling and confirmed that the 5.79m was enforceable. This was relayed to all competitors and the general membership through the IACA website at the time with the specific request that all countries begin discussions on this matter with their members and submit proposals to IACA. Not one complaint, proposal or suggestion was received. The proposed rule has not changed, we have amended one thing by changing the overall 30 cm measurement from the front of the hull to the stern purely to limit the possibility of a 2m long hull with a 3.79m long gantry and have included the raising of rudders for the clearing of debris. You rightfully state that skippers have been pulling one rudder up for the past 50 years. These boats I gather would fit the rule requirements when measured or inspected but what they do whilst sailing is up to them and other sailors to protest if not happy. I think over time it has just become an accepted practice. Unfortunately it does not make it right.
We often use the term “box rule” and this really does sum up our measurement rules (remember all measurements at measurement or inspection are taken either vertical, longitudinal or transverse to the hull centerplane). We have a 2.3m x 5.49m box that the hulls less rudder gudgeons fit in. A 5.49m x .4m (2.3m less .75m from centerline below the waterline) box that daggerboards fit in and a 5.79m x .4m box that rudder must fit in. We do not allow the daggerboards to go outside their box whilst racing so why would rudders be treated differently.
The Technical Committee has done their best to keep things totally transparent in this rule rewrite and to stay as close as possible to the rules already in place.
Acceptance can only be in terms of the constitution guidelines.


F.1.2
Q: The boom is also recognized as a spar, so it seems that the boom shall also be signed during the certification process. It should be "mast spar" not "spar" as in ERS?
A: The rule relates to spars and as you state in ERS (F.1.3 & F.1.4) this covers both mast and boom. The boom is only measured if its vertical dimension is more than 1.5 times its transverse dimension. In this case the boom would require signing and noting on measurement form. The wording adequately reflects this.


G2.1(c).
Q: Anti fouling boom sleeves?
A: The anti fouling boom sleeve is the sailcloth structure used by many sailors under their boom to stop the cascading mainsheet system from dropping down when not under tension. It was added to our interpretations (no.5) after the 2010 worlds in Cesenatico when it's area was included in the boom measurement by the equipment inspector. (The area of the boom is added to the mast and sail area if the booms height is more than 1.5 times its width). The word fouling also means entangling in English.


H1.(h)
Q: Is this a new rule?
A: Wording is identical to current championship rules.

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