The ultimate Australian-made private expedition powercat

When it comes to custom long-range aluminium cats, you would do well to shop around in the powercat state of Queensland and to consider Yanmar's wide range of diesel engines designed for all kinds of specialist and one-off applications.

Take Ellora II, a stunning catamaran from Rob Goode’s shipyard Coral Coast Marine Constructions (CCMC) in Bundaberg, for a demanding owner who wanted commercial-quality engineering and engines.

Goode, who has spent a lifetime working on the water and knows commercial and recreational boats, knows a thing or two about cat hull configurations.

LONG-RANGE HULL
"We don’t do deep skinny catamaran hulls," Goode explains. "My hulls tend to be a wider, semi-displacement design so as to deliver the optimum in ride, tracking and efficiency.

"Based on my commercial fishing background, I have settled upon a hull design that performs exceptionally well without the need for a lot of horsepower. I have applied this design concept to bigger hulls and it works brilliantly."

Ellora II has an overall length of 22.5m, beam of 6.8m and a displacement of 54 tonnes fully loaded. The load includes 12,000 litres of fuel plus 3500 litres of water.

The sponsons have a steep deadrise in the bow of 60 degrees, flattening out to a modest deadrise at the stern of 8 degrees.

Deep keels extend along the bottom of the sponsons to the prop, a design feature which greatly assists to keep the hull tracking truly.

EXPEDITION NEEDS
The owners of Ellora II live in Darwin. Having enjoyed cruising the remote but distant Kimberley region in their previous CCMC 18M hull with a pair of 509mhp Yanmar 6CXB-GT engines, Goode was approached to build their next biggest boat.

"Long before we lay down the keel, we spend a lot of time with the customer to get the interior design and appointments to their exact liking," Rob Goode said.

"With Ellora II, the owner was very technically minded so he wanted an engine room fit out that was of a high standard with specific requirements for long range remote operation cruising capability and redundancy."

A high capacity water-maker and twin generators were said to be mandatory options for this discerning owner. As a result, the list of included equipment was understandably long which made the hull heavier than usual.

COMMERCIALLY RATED YANMAR ENGINE
The propulsion system selected for Ellora II was a pair of Yanmar 6HYM-WET engines, matched to ZF 335A transmissions with a 1.767:1 ratio. Due to the remoteness of the intended cruising grounds, an engine with a mechanical fuel system was a key priority.

Yanmar’s 6HYM-WET model is a purpose-built commercial marine engine, a six-cylinder in-line configuration with a displacement of 13.73 litres and a dry weight of 1386kg without the transmission.

This model includes Yanmar’s latest combustion chamber design, named ASSIGN, a system originally pioneered by Yanmar on their large bore, low speed propulsion engines. These engines are IMO Tier 2 compliant, ensuring emissions are exceptionally low.

This technology combined with Yanmar’s mechanical fuel system is said to deliver impressive fuel consumption and provides private and commercial operators with excellent fuel economy, long life and high reliability.

The Yanmar 6HYM-WET installed in Ellora II is rated at 515kW (700mhp) at 2200rpm.

Swinging 30in x 28.5in five-blade counter-rotating props, Ellora II claims a top speed of 24 knots at 2240rpm. A comfortable cruise speed is said to be 20 knots at 2000 rpm, although the most economical long range cruise speed of 17 knots is recorded at 1800rpm, the Yanmar report says.

In addition, this is a low-maintenance boat for our exploring Australia wild northwest, with oil and filter service intervals on the Yanmar 6HYM-WET specified as standard at 500hrs. More on Yanmar at
www.powerequipment.com.au and Coral Coast Marine Construction on (07) 4154 1506.