Whilst the DUKW is the most favoured amphibious workboat yet built, it has limitations in all aspects of its design. Examples are that the bow is not shaped for optimum movement through water and buoyancy distribution is not optimal, leading to a tail-heavy orientation in the water.
These issues and many more, have led maritime and road transport regulators to impose higher safety standards for commercial use. Indeed, the UK’s Maritime and Coastguard Agency [MCA] has stated that in future they will not certify further DUKW conversions because of design and structural limitations.
The hull, deck and canopy are constructed from glass reinforced plastic (GRP) instead of previously used steelwork with its associated high maintenance. This is an obligatory modification in order to meet new safety standards on hull thickness and corrosion, whilst limiting any increase in weight.
GRP substantially reduces maintenance needs and costs compared with steel which requires regular rust prevention measures and repainting.
Both road and water-drive systems are powered by higher horsepower rated, energy-efficient engines which meet latest environmental standards. The up-rated power units provide greater speed, enhanced manoeuvrability and therefore greater safety on the water.
The traditional calliper and wheel drum mechanisms have been replaced by hydraulic drive systems incorporating internal disc brakes. This eliminates the water and corrosion damage to mechanical parts; a major reliability, safety and maintenance issue on all past models.
On the water, a jet drive propulsion unit providing both power and steering, replaces the old propeller drive system. This quantum leap in the design enhances speed, manoeuvrability, safety and reliability.
Optimum efficiency in the management of these drive trains is achieved with bespoke electrical and electronic systems
In the SeaHorse, all key aspects have been re-evaluated and modern solutions have been found which have to comply with the most stringent certification requirements, whilst retaining the core iconic theme and shape of the original DUKW.
The SeaHorse has been designed and built in collaboration with the UK’s Maritime and Coastguard Agency [MCA ] and the Vehicle Operators Standards Agency [VOSA ] - both being compliance offices of the Department for Transport.
Power is transferred by hydraulic systems for both road and water drive trains.
For road power, four or six wheel-located motors are used (dependant upon end-user drive power requirements). These are inherently more efficient in power transfer terms.
For power afloat, hydraulics replace conventional prop-shafts, thereby eliminating through-hull apertures, which are a critical area of both weakness and safety. These aspects required constant vigilance, inspection and extra maintenance in the original designs.
