VESSEL REVIEW | Whale Dreamer – Sightseeing and events catamaran built for Australia's coastal waters

Thai/Australian builder SeaCat Ships recently delivered a new semi-displacement catamaran vessel to local tour operator Sapphire Coastal Adventures.

Whale Dreamer was designed by SeaCat affiliate SeaSpeed Designs. SeaCat said the bespoke aluminium catamaran has been purpose-built for operations in Sydney’s exposed coastal waters. The vessel has an LOA of 23.4 metres (76.8 feet), a beam of eight metres (26 feet), a draught of only 1.65 metres (5.41 feet), a crew of five, and space for 145 passengers.

Based on SeaCat's semi-displacement deep-vee hull platform, Whale Dreamer delivers enhanced seakeeping performance in offshore conditions. The vessel provides a smooth and controlled ride in swell, with reduced slamming and excellent stability, ensuring passenger comfort.

“The hull form has been carefully refined to minimise resistance while still providing a smooth and comfortable ride in exposed coastal conditions,” Paul Birgan, Managing Director of SeaCat Ships, told Baird Maritime.

Built for both versatility and economical operation

Certified under NSCV Class 1C survey for up to 150 passengers, the vessel has been optimised for high-frequency tourism operations with practical passenger flow and operational efficiency in mind.

“The owner required a modern, economical, and reliable whale watching and events vessel capable of operating comfortably in offshore coastal conditions while maintaining low operating costs,” said Birgan. “The brief focused heavily on passenger comfort, fuel efficiency, visibility, and safe passenger flow around the vessel. The owner also wanted a platform suitable for multi-purpose use, including tourism cruises, private events, and seasonal whale watching operations.”

Another important requirement was compliance with the latest pollution and emissions regulations in New South Wales, particularly in Sydney and along the South Coast where the vessel will be operated, while still delivering strong commercial performance and reliability.

Powered by twin Yanmar 6HYWET 700hp (520kW) diesel engines driving fixed-pitch propellers via shaftlines, the vessel can achieve a top speed of 26 knots and cruise economically at 21 knots with a fuel consumption of approximately 75 litres (16 gallons) per hour per engine.

“This setup was selected for its simplicity, reliability, efficiency, and ease of maintenance in commercial tourism operations,” added Birgan. “The propulsion system has been carefully matched to the proven semi-displacement hull design to provide excellent cruising performance, strong offshore capability, and low fuel consumption while maintaining comfortable passenger operations.”

A key feature of the propulsion package is the vessel’s ability to achieve strong operational performance with comparatively low horsepower requirements. The refined hull design and efficient propulsion integration allow the vessel to deliver economical operations while still maintaining the speed and handling characteristics required for commercial whale watching duties.

The mini-keel arrangement meanwhile provides additional protection for the running gear during coastal and harbour operations.

Electronics suite selected for reliability and ease of use

The vessel is fitted with a comprehensive Garmin commercial marine electronics package that Birgan said is suitable for offshore tourism and whale watching operations. The system includes integrated multifunction navigation displays, a radar, GPS navigation, a depth sounder, an AIS, VHF communications, and vessel monitoring systems.

“The electronics suite was selected to provide operational reliability, ease of use, and full compliance with commercial survey requirements, while also delivering excellent situational awareness for coastal and offshore operations around Sydney and the NSW South Coast,” Birgan told Baird Maritime.

The integrated bridge system provides a simple and highly user-friendly operating environment for the skipper and crew, with all key navigation and vessel information accessible through a centralised interface.

“The focus of the electronics arrangement was reliability, operational practicality, and ease of maintenance for high-frequency tourism operations. The system also provides excellent visibility and situational awareness.”

Excellent views from anywhere on board

The vessel also features full walk-around decks and large three-level viewing areas, which greatly improve passenger movement, sightseeing opportunities, crew access, and overall operational safety during whale watching activities. The layout allows passengers to move safely and comfortably around the vessel while maximising viewing opportunities during tours and events.

“The multi-level viewing arrangement creates a much more open and interactive passenger experience, which is particularly valuable during whale watching operations.”

For Birgan, one of the main challenges was balancing operational efficiency with regulatory compliance under the latest NSW environmental and pollution requirements.

"The design also needed to provide excellent passenger comfort and stability during offshore whale watching operations while still maintaining economical fuel consumption and practical maintenance requirements," he told Baird Maritime. "Passenger movement and visibility were also key design considerations, which led to the incorporation of the full walk-around deck arrangement and multi-level viewing areas."

Also, as the vessel was built entirely in aluminium, maintaining weight control throughout construction was critical to achieving the desired performance and fuel efficiency targets.

“Another challenge was integrating the vessel systems and propulsion arrangement while meeting the latest regulatory requirements and maintaining ease of maintenance for the operator. As with many modern commercial vessels, supply chain timing and coordination between multiple equipment suppliers also required careful management throughout the project.”

Birgan nonetheless remarked that the work on Whale Dreamer reinforced the importance of refining proven hull platforms rather than reinventing successful concepts. By continuing to evolve an established SeaSpeed catamaran platform, SeaCat was able to achieve very strong efficiency and performance outcomes with a relatively low total installed power.

“The project also provided valuable experience in integrating modern environmental compliance requirements into commercial vessel operations without compromising commercial viability. Passenger flow and usability also continue to be a major focus, and the success of the walk-around deck arrangement will certainly influence future tourism vessel designs.”