Earlier this month, another Australian ship designer and builder Wavemaster International said it was close to completing a deal to build two high-speed ferries for Chinese owners to put into service outside the Pearl River delta region.

Wavemaster delivered earlier this month the Peng Lai Hu, the third ferry the company had built for the Jiangmen Hongkong-Macau Joint Passenger Transportation Co, and is scheduled to complete a fourth vessel in August.

The company also delivered the Nansha 11 to the Panyu Nansha Ferry Co, a Hongkong-China joint-venture over the same period and is scheduled to complete a follow-up order for the Nansha 12 in July.

A further two are nearing completion and will be launched later this month.

The latest orders have been placed for the Hui Yang County Daya Bay Development Company, the Taishan Guanghai Port corporation, and the Xin Gang Passenger Transportation Corporation.

The Hui Yang ferry will carry 368 passengers, Taishan 338 and Xin Gang 318 on regular services from Hongkong to ports in the Pearl River delta of China's Guangdong province.

Two of the ferries will be the first to be fitted with Austal's computerised ride control system that employs a series of fins and flaps to smooth rough seas.

''Our round bilge, bulbous-bowed catamarans are extremely stable and sea kindly, but the ride control system will ensure even greater passenger comfort,'' said Austal's technical manager Jim Black.

''It will guarantee significantly smoother operation in rough seas, even though the vessels will be operating in more exposed waters than our previous deliveries.'' Mr Black said the up-and-down movement of vertical acceleration was the major cause of passenger discomfort and seasickness in conventional craft.

''This is what we have reduced with our ride control system,'' he said.

He explained that a computer would read the acceleration at four points and then decide what response was required.

It then sends a signal to the fins and flaps, effectively adjusting buoyancy and significantly improving passenger comfort, he said.

Mr Black said previous systems required considerable input from the vessel's skipper who had to tune the system each time there was an alteration in course or sea conditions.

''Different systems required different amounts of this manual input, but ours is completely automatic,'' he said.

There was only one switch and once the skipper turned it on the computer did the rest, he added.

Two Austal catamarans will have a pair of fins on the inside of the hull tunnels at the bow where they are protected from damage during berthing manoeuvres, and a flap at the stern of each hull.

Construction of the vessels has commenced, with delivery scheduled for June, while the third ferry will be started next month and delivered in September.