Pacific 2012: Gaining one's Sealegs | ADM Dec 2011 / Jan 2012
Nigel Pittaway | Melbourne
The Sealegs family of boats have hydraulically-retractable wheels, much like those of an aircraft, which make them a go-anywhere, do-anything platform with recreational, military and paramilitary applications.
Sealegs International is an innovative company listed on the New Zealand Stock Exchange. It has not only solved the problem of simplified handling but developed a fascinating capability with appeal to Search and Rescue organisations and Special Forces troops alike.
Will Burrell, a long time Sealegs owner and a former director of Sealegs International, and David Henry, an industry sector specialist, have joined forces to market the concept to defence and emergency services in the region. The concept is not new, however, and over 600 hulls have been sold throughout the world over the past five years. Of that total, 100 are in commercial use and have amassed thousands of working hours.
Customers include the Mumbai Police Force, Malaysia’s Bomba Den Penyelamat (Fire Service), Royal Thai Navy, Italian Vigili Del Fuoco (Fire Department) and the New Zealand Coastguard.
The boats are capable of over 35 knots in the water and can be driven at 10 kilometres per hour on land. Moreover, the three 25” x 12” all-terrain tyres can cope will all sorts of ground, including soft sand and rocks.
The obvious military applications include the delivery of Special Forces and/or sensitive equipment across the beach, or during estuarine operations. For Search and Rescue the response time is attractive - it can be at full speed on the way to a distress call literally within seconds of starting the engine on the boat trailer.
According to David Henry, the Victor Harbour-Goolwa Sea Rescue organisation in South Australia credits this rapid response time with saving of two or three lives since taking delivery of their boat in 2009. The Sealegs boat can drive right out of the water to a waiting ambulance, thereby alleviating the risks associated with patient transfer from a conventional vessel.
There are three basic versions, a 6.1-metre D-Tube and 6.1 and 7.1-metre Rigid-hull Inflatable Boats (RIB). The structure is made out of 4mm thick (5mm for the 7.1 metre craft) 5083 marine grade aluminium and weighs 1,090 kg (D-tube), 1090 kg (6.1 metre) and1,220 kg (7.1 metre) respectively.
The two smaller designs are powered by a 115 horsepower Evinrude E-Tec outboard and the 7.1 metre vessel by a larger, 150 horsepower variant. All three are powered on land by a 24 horsepower air-cooled Honda four-stroke inboard, which drives the wheels through a hydraulic coupling. Both engines use the same 80-litre fuel tank.
Maximum speed for the two 6.1 metre boats in the water is 65 kilometres per hour and the larger 7.1 metre vessel can achieve 78 km/h, thanks to its more powerful engine.
David Henry says a customer in Singapore has specified an electric inboard motor to drive the hydraulics, which has further appeal for Special Forces operations where quiet operations are necessary.
The company has also proposed a 10 metre twin-outboard version for Special Forces applications, capable of carrying 14 passengers (including the driver) over 200 nautical miles at 30 knots. Maximum design speed is 40 knots in the water and 15 kmh on land. A further option for twin waterjets, powered by inboard engines, is also on the drawing board.
“The boat is not a toy,” said Will Burrell. “It is proven in service and there is no risk associated with it at all. It is seaworthy in conditions up to Beaufort 3 and Sea State 4 and it has circumnavigated both islands of New Zealand and the Malaysian peninsula.”
“It can go pretty much anywhere a quad bike will go,” he adds, “and is treated like a conventional boat whilst in service, requiring only a wash down after use.”
He says the boats are approximately 150 kg heavier than conventional equivalents and cost about 30 per cent more. The ballpark figure is currently around $100,000 per unit.
For military operations, they are capable of being slung underneath a helicopter and have already been air-transported inside a C-130 Hercules. They can also be hoisted aboard the Navy’s larger surface vessels.
At the present time, all hulls are built in Auckland, with around a 90-day lead time for delivery, but Burrell says that should an order of sufficient size come from an Australian customer, consideration will be given to local production.
The introduction of the two Canberra Class LHDs and the consequential transition of Army to an amphibious warfare taskforce could well provide opportunities beyond the traditional Navy Clearance Diver application.
Although there is no specific requirement for a small amphibious vessel in the current Defence Capability Plan, the benefits of Sealegs may be hard to ignore.