It seems that the UK is fast becoming a centre for innovative amphibious vehicles. The Aquada sports car/speed boat hit the headlines last month racing round St Katharine Docks in London and now a hovercraft/rigid inflatable boat (RIB) concept has been shortlisted for a prestigious design contest.
Coupland Bell of Coventry is developing the craft which combines the features of a hovercraft and a planing boat with the ability to negotiate mud and shallow or fouled water – all in bad weather conditions. The 6m-long RIB is designed for rescue, commercial applications and disaster or flood relief. It will carry six passengers or half a tonne of cargo plus a crew member and can be towed by a 4×4 car.
The craft has all the advantages of a hovercraft, which means it can be launched from a beach or riverbank. But unlike conventional hovercraft, its skirts can be retracted on the move, transforming it into a planing boat. It can then operate in winds up to Force 6 and remain safe to Force 8.
The propulsion system is a marriage of designs, combining the effects of a fan with a propeller or water jet. This system gives good acceleration and manoeuvrability while enabling the craft to resist high winds.
The craft has been shortlisted for the annual Concept Design Award, run by the British Marine Federation and the Royal Institute of Naval Architects. The finalists were announced at the Southampton Boat Show and the winner will be revealed in January at the London show.
The craft’s bow and hull are constructed to allow clear water to pass through the propeller even when the quality of the water through which it is travelling is poor, such as in flood conditions. When it operates as a boat, drag is reduced by lifting the skirts out of the water. The steering and propulsion systems are arranged to ensure they cannot be damaged when operating in shallow water or on land.
The craft uses conventional materials such as glass-reinforced plastic (GRP) and is powered by a standard 140bhp turbo diesel truck engine.
The machine’s construction, ease of maintenance and low retail price – around half the price of similar hovercraft – make it suitable for applications in the developing world, according to its chief designer Mark Evans, director of Coupland Bell.
‘We see this craft as being robust enough to tackle disaster relief in the developing world but also able to compete in the commercial market in the UK,’ he said. ‘After all, is there any other craft that can launch a rescue from a riverbank, a beach car park or a sandbank and still be safe in a Force 8 gale?’