Accelerate - November 2013

Giving larger craft their Sealegs

The recent launch of Sealegs International’s next-generation SLG-100 product means that significantly larger craft than before can now be fitted with the company’s patented amphibious technology.

The SLG-100 is targeted at craft in the range of 8 to 11 metres, and a gross laden weight of 6,000 kgs. Sealegs’ current amphibious technologies cater for craft up to 2,500 kgs gross laden weight.

“This will take Sealegs strongly into the commercial, industrial, public service, enforcement and military markets that provide the potential for substantial global growth,” Sealegs Chief Technology Officer, Maurice Bryham says.

“While Sealegs builds amphibious craft, the unique and high-value elements are the amphibious technologies, rather than the boats themselves, and our goal is to develop a wider portfolio of patented amphibious technologies.”

Bryham says there were a number of technical elements in the project that led to the need for R&D assistance, from working with experts to establish engineering and design limitations, to assessing the complexities of making an entire amphibious system function with hydraulic, mechanical and electronic subsystems.

A $247,000 R&D grant from Callaghan Innovation enabled Sealegs to evaluate a wide range of materials, engineering and process options on an accelerated timeframe.

“There was an element of prototyping with Callaghan Innovation, but the development project went substantially past proving the concept and had resulted in a near- production solution from which commercialisation could commence in a structured and strategic manner,” he says.

Callaghan Innovation Investment Manager, Michael Fielding, says that not only were there surprisingly tough engineering challenges to overcome in the project, but the grant also allowed the company to use outside expertise in areas such as control systems, where they needed to develop their product and upskill their team.

“While many Kiwi companies take a go-it-alone approach, Sealegs believed it would be quicker, better and cheaper to engage with specialists in a range of pertinent technologies; we encourage other businesses to look at those sorts of options as well.”

Sealegs is the world’s leading manufacturer of patented amphibious craft. With 10 years’ experience and development, there are now over 800 craft in more than 35 countries around the world.

To find out more about Sealegs International, see

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How does the Sealegs system work?

The Sealegs system consists of motorised, retractable and steerable wheels that are fitted to specially designed boats. The boat can be driven from a storage location, down a boat ramp or beach and into the water – all with the occupants staying in the boat and remaining completely dry.

Once the boat is in the water, the Sealegs wheels are retracted and the boat is then driven and used as normal. As land approaches, the wheels are lowered while the boat is still moving. Once the wheels touch the bottom, the boat can be driven onto land and the occupants can disembark, safe and dry.

Updated: 7 September 2015