Regatta-forum

Hi !
Das minimal zulässige Rumpfgewicht incl. Schwert ist von 119 auf 116 kg reduziert worden, was nicht nur das Nachwiegen sondern auch einen zeitaufwendigen Pendeltest zur Folge hat und daher sehr kontrovers diskutiert wird.
Insbesondere wird zu Recht erwartet, dass 3 kg Mindergewicht keinen nennenswerten Einfluss auf die Bootsgeschwindigkeit haben.

Die wahren Gründe für die Gewichtsreduzierung nenne ich im folgenden:

Das Finn. wie es kurz genannt wird, wurde 1949 von dem schwedischen Segelkanudesigner Richard Sarby für die olympischen Spiele 1952 (Heslsinki) konstruiert und ursprünglich in Holzbauweise hergestellt.

60 Jahre später ist das Finn infolge einer weitgehend klugen Klassenpolitik immer noch das Nonplusultra für den ambitionierten Regattasegler.
Zahlreiche Verbesserungen, wie z.B. ein hinsichtlich Massenverteilung und Torsionsflexibilität optimierter GfK-Rumpf in Doppelbodenbauweise, modernste Carbonwingmasten, formstabile faserverstärkte Folien-Segel, die mannigfaltigen Trimmmöglichkeiten und die zeitlos schönen, unveränderten Linien machen das Finn zur schnellsten und attraktivsten (trapezlosen) Einmannjolle.

Um den Olympiastatus zu erhalten, wurde es erforderlich, eine weitere Anpassung an die technische Entwicklung vorzunehmen und den als fortschrittlich angesehenen elektronischen Kompass zuzulassen. (O-Jollen und andere Klassen hatten diesen Schritt bereits vollzogen.)

Der Austausch des Magnetkompasses gegen den 1,5 kg leichteren elektronischen Kompass hätte (ohne weiteren Gewichtsausgleich) jedoch zu Vermessungsproblemen geführt.

Unsere modernen Finns sind nämlich unter Ausnutzung der Vermessungstoleranzen bis an das erlaubte Limit ausgereizt.
Der zentrale Gewichtsschwerpunkt liegt möglichst weit hinten (bei 2100 mm) und die Bootsenden sind leicht, damit das Vorschiff samt Mast und Segel aus hydro- und aerodynamischen Gründen möglichst wenig auf- und ab bzw. hin- und herschwingt.
Der Austausch des Kompasses hätte (ohne weitere Massnahmen) dazu geführt, dass der Gewichtsschwerpunkt sich zu weit nach achtern in den unerlaubten Bereich verschoben hätte.
Als Lösung bot es sich an, dem Heckbereich zum Ausgleich ebenfalls 1,5 kg zu entnehmen, so dass sich 2 x 1,5 = 3 kg als Gewichtsreduzierung aufdrängten.

Sicher hätte man die im Bereich der Bootsmitte (in den Seitentanks) befindlichen Ausgleichsgewichte auch weiter vorn platzieren können, um den alten Gewichtsschwerpunkt wiederherzustellen. Diese Variante hätte jedoch einen noch grösseren Arbeitsaufwand bedeutet.

Fazit: Die Zulassung des elektronischen Kompasses war der eigentliche Grund für die Verringerung des Rumpfgewichtes.
Die kaum messbare Verbesserung von Speed und Handling (on shore) sind m.E. lediglich als winzige Nebeneffekte anzusehen.

Richard Hart on Finn Class Rules


“Dear Sailors

There seem to be concerns about the weight reduction.

This is the result of a democratic decision of the AGM, which went further than the proposal worked out by your Technical Committee including myself. I believe that the decision is a good one.

Some comments:

1. The Submission to allow simple digital compasses was delayed until the end of this Olympic Cycle because there was a weight and Lamboley issue. As I recall, various critical comments appeared on your website because we didn't do it 2 years ago.

2. Because the spherical compasses are heavier than the new ones, either a weight reduction is needed, otherwise more correctors (the TC proposal), because the majority of modern Finns already have the maximum 5 kg of lead in. Bryan Boyd put it very clearly.

3. AGM decided that it is stupid to sail around with extra lead in for the next 20-30 years, just to suit the system. When the magnetic compass comes out the boat should be re-swung anyway. From your website, I formed the opinion that most North American Finn sailors want to change the compass, and I think the same applies in other parts of the World. If it's sensible to get some weight out, let's do it now.

4. Although I wasn't there this year, AGM considered that a reduction of 3 kg was achievable without making existing boats obsolete This is particularly important in our Class because of the very long "first class" life of the hulls (I fully agree with Steve Landeau: I have a 2003 boat).

5. Having received instructions from AGM, I made calculations to decide whether the permitted minimum Radius of Gyration should be altered, and whether it is likely that existing boats will no longer be able to "optimise" (to minimum weight, LCG max aft, Gyration minimum). From the calculations, I judged that it was best not to change the Radius from 1100 mm, and that the vast majority of existing boats built since the 1980s should be able to remain optimised, or be trivially worse off.

6. The various rule changes required by AGM, including also removal of the requirement for a paddle and bucket (there were others which were housekeeping or commonsense alterations) were written out, agreed by TC and sent to ISAF first as a discussion proposal at the end of July, then as a formal Submission on 13 August.

7. Since that time I have made frequent enquiries about progress, and made amendments to the wording as requested by ISAF, always within the remit of the AGM instructions: Neither the Class Executive nor TC through its Chairman are permitted to change the substance of our rules without direction from the Council (AGM).

8. I asked throughout for a target date of 17 November, being the first day after the ISAF Conference. The ISAF procedure for Class Rule changes is that there is a rolling programme, but it was accepted that some circumstances might arise that needed debate by the full ISAF Class Rules Sub Committee. In the end we have 24 November: Sorry that's awkward for your Thanksgiving Regatta, but it gives more time before Christmas Regattas down under, and before next Summer in the Northern Hemisphere.

9. The builders have not influenced the Submission. They have put pressure on me to seek a swift result to the ISAF considerations: One builder has one or two boxes of new Finns ready to go to the US West Coast and wanted before Christmas, another is saying that buyers are holding off so that they can get boats to the new spec. In my opinion the pressure is completely reasonable and I have a duty to support their (our) interests in this matter.

10. "Nothing worse than a boat-builder, except maybe those awful volunteers that are always getting in the way at the regattas, waving their stupid rule books & saving lives all that crap! What is the matter with those people?"

1. I have taken care to include boat builders on the Technical Committee, where they have made valuable contributions. They are likely to suffer at least as much as the existing owners if the Finn gets trashed. Although I can't remember a formal vote on TC - we work by consensus - I would exclude a vote from an "interested party", in the narrow sense of the term.

2. As an awful volunteer, I have been since 1989 the leader of the team responsible for controlling the rate of development of the Finn. My position is subject to re-election each year.

11. One major cause of the delay from ISAF is that they are worried that we have a class that is pretty well right at the moment, and don't want people cheating by ending up with illegal boats. That's up to the sailors.”



I hope that the above helps to clarify the matter.

With Best Wishes

Richard Hart

Chairman IFA Technical Committee.

GBR ≈ 631