On 10 March, 2021 the International Etchells Class Association (IECA) confirmed that boats produced by Pacesetter Etchells Pty (Pacesetter) since 2011 from Mould 11 (M11) were not valid Etchells Class Yachts under the Class Rules of the IECA.
Andrew Cumming, outgoing Chairman of the International Etchells Class Association (IECA) describes in the latest edition of the class quarterly newsletter Newsletter, how the class sought a solution for the 25 boats built from the M11 mould.
- The first step in 2021 was to assemble an international panel of marine architecture experts.
The Modification Panel led by Tom Schnackenberg (NZL) were to independently evaluate the differences between M11 boats and Etchells.
They were empowered to study the shape differences between the boats and try to come up with some sort of modification to the M11 boats which would allow them to ultimately race level against Etchells.
- The goals were to (a) modify the existing M11 boats and (b) create a new mould (the M12) for the manufacture of class-rule-compliant Etchells sailboats in Australia.
The Build Panel was struck consisting of the builders, independent expert Grant Simmer (AUS), several members of the class One-Design Technical Committee (ODTC), with Chairman Andrew Cumming and IECAA President Martin Hill as observers.
In 2022 . . . the M11 Modification Panel confirmed that the M11 shape produces less drag than the Plug 2 shape, especially at speeds approaching the hull speed.
- In order to equalize the drag, the panel happened upon a brilliant solution (inspired in part by a suggestion offered by Jamie McWilliam)
If the M11 boats have essentially the same sections as Etchells, but just a reduced rocker perhaps Etchells speed characteristics could be restored by simply adding back the rocker.
A digital version of the M11 boat was sliced from keelson to sheer (but leaving the deck intact) along station planes fore and aft of the keel.
The virtual boat was then lifted in the bow and stern to put back rocker. Various degrees of lift were applied to the bow and stern and CFD analysis performed and compared to the Etchells shape.
In this way, the rocker was fine-tuned until the drag differences across a wide range of hull speeds were reduced to very nearly zero, and a final shape determined.
Martin Hill graciously offered up his M11 boat (AUS 1484) for modification under the new protocol, and the Build Panel determined the practicalities of modifying the M11 boats as specified by the M11 Modification Panel.
Eight M11 boats have now been modified and have been racing in events in Australia.
The panel also oversaw the construction of a new mould (M12) to be used going forward for the manufacture of Class–Rules–Compliant Etchells sailboats in Australia.
Innovation Composites of Nowra, NSW will be the builder of the mould and ultimately be licenced to make Etchells from that mould, once it has been verified and approved by World Sailing.
There have been no structural issues with the modified boats and early indications are that they perform in line with Etchells Class sailboats.
The long-term status of these boats will be determined by a class vote in April 2024
Read the Chairmans document here . . .
The AON 2023 ETCHELLS WORLD CHAMPIONSHIP, hosted by Etchells Fleet 20 Biscayne Bay, Biscayne Bay YC, Coral Reef YC and Shake-A-Leg Miami, from 12 to 21 April, 2023.
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