GTS-43 - Australian-built racer

Boat Test - GTS-43

The first of Sydney Yachts new Ker-designed IRC racers has hit the water. Roger McMillan takes a quick look.

“A 43ft boat that is able to match the faster 45ft cruiser-racers around the track in all conditions, plane away from them as the wind increases and give a very good chance of winning on handicap” is how Sydney Yachts describes their new Ker-designed GTS-43.

We will soon know whether the design, which certainly looks like a speed machine, lives up to the hype. Three boats have already been sold and at time of writing a fourth was “extremely close” to being contracted.

Hull #1 was bought by CYCA member Warwick Sherman and christened Occasional Coarse Language Too, to replace his Cookson 39. It was launched in time for the Sydney Boat Show in July and is competing in club races on Sydney Harbour before doing the Pittwater to Coffs race in January.

“We’ve been spending time tuning and working out how to sail her, but so far we are thrilled with her speed and ease of handling,” Sherman said.

The second boat has been bought by an Asian-based yachtsman and will debut in the King’s Cup in December, while the third boat will be based in Hong Kong.

At a time when the Australian marine industry is reeling under the assault from Asian manufacturers because of cheap labour and a high Australian dollar, these sales into Asia are a great credit to new Sydney Yachts owner, Darren Williams and his team. Williams acquired Sydney Yachts less than 12 months ago and quickly set about restoring the high reputation that the company earned with designs like the Sydney 36 and 38, many of which are still winning in open competition.

Jason Ker’s thinking

Ker Yacht Design has a reputation for “getting IRC right”. The British designer and his team use highly-computerised design tools to explore a range of options in hull shape and rig before settling on the one most likely to give good performance and a competitive rating. Since Jason Ker’s first major success in the 2003 Admiral’s Cup with Bribon, the design office has enjoyed success in most major international regattas.

The thought-process for the GTS-43 followed the proven Ker formula. “We first explored the low-road in weight, putting on a fin without bulb in order to reduce the required sail area and keep the rating down, but aside from being competitive we couldn’t really get excited about the concept and couldn’t see why the end customers would either. We were stuck in a middle ground with a modern hull shape and form stability in spades but still too heavy to really take advantage of the advanced shape,” Ker said.

“So, not satisfied, we threw away what we’d done and went back around the design loop – much lighter with the overall displacement, bulb keel, taller rig. When we computed the drag with the CFD codes and crunched the numbers in the VPP, we found that not only had we made a significant gain in speed, but the handicap competitiveness was also improved, which was later confirmed by the trial certificate.”

Ker says that an important side benefit of this development is that this “more voluminous hull form type” is also well favoured by the ORCi rule, unlike what he describes as "the narrow canoe hull forms" of the contemporary IRC cruiser-racers, which are usually disliked by ORCi.

The Ker design team says it strives to produce “all-rounders” which can finish at the front of the field whatever the conditions. The big sailplan of the GTS-43 should ensure good light airs performance while the hull form offers good stability for reaching and upwind.

“Most of her competitors are relatively heavier,” Jason Ker says. “We found through our CFD analyses that with our powerful hull form we were able to reduce displacement while still remaining competitive in windward-leeward racing, but gain a lot of performance downwind as the wind increased and in light airs. Of course a great side benefit of reduced displacement is that the boat will be more responsive and fun to sail.”

Solid construction

The GTS-43 is designed to go offshore, so the structures are built in accordance with American Bureau of Shipping Guide for Building and Classing Offshore Yachts and meet ISO standard (12217 and 1215-5), CE, Lloyds and ISAF regulations. However, Jason Ker makes the point that “strong” doesn't have to mean “heavy” if the right construction techniques are used.

A marine-grade, hard-anodised aluminium keel grid provides stiffness and the hull is laminated with vinylester resins using biaxial and double bias fabric. Closed cell foam core is used in hull and deck construction and the main structural bulkhead is moulded GRP, laminated to the hull and deck.

The interior is obviously designed with racing in mind, but there are some considerations to cruising. There is a well-equipped galley with two-burner spirit stove/oven, a separate head, a generously-sized icebox and three double cabins, but the pipe berth above the otherwise comfortable-looking saloon really gives the game away. This boat is built to go to Hobart.

The “standard” mast and boom are aluminium to keep the base price affordable, but all the boats sold so far have gone with the high-modulus carbon option. The boat features a 3/4 rig with a moderate 60m2 mainsail balanced by the large 47m2 jib, with a huge 195m2 asymmetrical spinnaker which flies off the 2.1m long carbon prodder.

The primary winches are Racing Black anodised 62STRs and the halyard and mainsheet winches are EVO 45STs. The cockpit is well set-out and the twin carbon composite racing wheels are a much better solution than the huge single wheels of earlier Sydney Yachts designs.

The coming season will show just how well this new Australian-built thoroughbred performs against imported boats. It is vital that Australia retains a viable boatbuilding industry and I sincerely hope that the GTS-43 is as fast as it looks.