Yanmar 6AYM-WGT Powers Reef Ranger

There’s no tougher operating environment in Australia, than the commercial marine market in Far North Queensland. It’s a market where the Yanmar marine diesel brand excels. In this harsh environment, dual Yanmar 6AYM-WGT engines have been specifically selected to power the $5m ‘Reef Ranger’, a vessel destined to spend 200 days a year at sea.
Designed by Incat Crowther and built on the Gold Coast by MEC Yachts , ‘Reef Ranger’ is a specialist 24m aluminium catamaran recently delivered to Queensland National Parks. The vessel is based in Cairns, but has the responsibility for patrolling the vast Great Barrier Reef World Heritage region, an area roughly the size of Italy or Japan.
Boasting a length overall of 23.99m and a beam of 8.5m, the ‘Reef Ranger’ has been designed to have a minimal impact on the environment that it is charged with protecting. At the centre of this cost-effective design is an excellent combination of deadweight, functionality and performance. Incat Crowther has developed a high-volume workboat hull, a vessel which offers greater capacity and operational envelope whilst maintaining excellent fuel economy.
With such a focus upon efficiency and minimal environmental impact, it is significant that a pair of Yanmar 6AYM-WGT engines were specifically selected to power this ground breaking vessel. The Yanmar 6AYM-WGT is a six in-line cylinder engine with a displacement of 20.39 liters and a rated power output of 911 mhp (670kw) at 1,938 rpm. This Yanmar model is noted for its strong performance, low fuel consumption and low emissions.

Reef Ranger 3
The versatile 6AY Series is extensively used in many applications including heavy displacement work boats but also in many high speed applications such as passenger ferries, patrol craft and cray fishing boats. In addition to the Yanmar engines, dual Northern Lights M65C2 gen sets have been installed in the ‘Reef Ranger’ engine room. Below decks is 12,000 litres of fuel, 4,000 litres of water, a 2,000 litre sullage tank and 3.5” diameter propeller shafts equipped with the high quality PSS dripless shaft seals.
With a maximum speed of 25 knots and service speed of 20 knots, ‘Reef Ranger’ is twice as fast as its 24 year old predecessor. With the modern Yanmar 6AYM-WGT marine diesel engines installed in the engine room, the ‘Reef Ranger’ is more environmentally friendly and significantly more cost effective. “The Yanmar 6AYM-WGT is the ideal power plant for this application,” said Michael Blair, National Marine Sales Manager for Power Equipment, the authorised Yanmar Distributor.
“This is a big boat that has high demands in terms of operational time at sea and speed capability while the environmental footprint has to be exceptionally low. The Yanmar 6AYM- WGT delivers on all counts. This is a very popular engine in the commercial market & one that has gained itself an excellent reputation in recent years amongst boat-owners.”
As well as being an efficient vessel at sea, the environmental credentials of ‘Reef Ranger” are boosted through the implementation of new technologies. These include extensive use of solar panels, high R value insulation, zoned air conditioning as well as window blinds and shutters to reduce the impact of the unforgiving FNQ sun.

The extensive array of solar panels takes full advantage of modern lithium ion batteries to reduce the use of diesel generation. Both under way and while at anchor at night, the intelligent control system combines power from the dual sources (solar and gen set) to ensure that running costs are minimised and the Northern Lights generators can be shut down at night.

Reef Ranger 2
Operationally, ‘Reef Ranger’ has a heavy schedule. Quite apart from the task of patrolling 348,000 square kilometres of ocean, the vessel is tasked with duties which cover environmental issues, zone compliance, tourism, moorings and fires on remote islands. ‘Reef Ranger’ can stay at sea for up to 12 weeks, has a cruise range of 2,000 nautical miles and can carry up to 28 people on board.