Developing a high-speed four-wheeler that could transform from an all-terrain vehicle to a watercraft cruiser had eluded engineers for decades.
“Although almost every automotive company in the world had some patents relating to amphibious applications, nobody had looked at it seriously. And what was being looked at related to low-speed amphibian applications,” Neil Jenkins, Chairman of Gibbs Sports Amphibians, said in an interview with SAE Magazines.
Gibbs engineers began working to develop a high-speed land and water vehicle 15 years ago, but their efforts intensified in 1998.
“Since then, we’ve had a very aggressive approach to owning our ideas, and our efforts have resulted in 300 patents granted as well as a large number of pending-patents,” said Jenkins.
Until the Gibbs’ Aquada set a world speed record of more than 30 mph on water in 2003, a land-water vehicle hadn’t broken the 9 mph barrier. The three-seat aquatic car initially planned and fully homologated for Europe faded from the production landscape with the bankruptcy of its engine supplier, England’s Rover Group. Now, the U.S. gets the first Gibbs vehicle via the single-occupant Quadski, which starts production in November 2012.
The Quadski has an overall length of 10.5 ft (3.2 m), a width of 5.2 ft (1.6 m), and a height of 4.3 ft (1.3 m). The 70.8-in (1.8-m) wheelbase vehicle has a 46° approach angle and a 26° departure angle. It weighs approximately 1300 lb (589 kg).
“At one point it weighed much less than that. But over the last two years of development as we focused on aspects of toughness and reliability, the vehicle gained weight. That’s why we worked hard to find the lightest solutions possible for every system and that included getting the best power-to-weight ratio we could for the powertrain,” said Jenkins.
Gibbs has a five-year powertrain contract with BMW.
On the Quadski application BMW’s four-cylinder, 175-hp K1300 engine is fitted with a Gibbs auto-clutch that connects to a six-speed gearbox. The transmission links to a Gibbs-developed automated gearshift that is activated via a thumb rocker-switch on the handlebar’s left side.
“The output from the gearbox drives a Gibbs-designed PTU [power transfer unit], which splits the drive between the jet pump and the differential. It also has an electric reversing motor and a decoupling device to ensure that the differential is not driven when in marine mode,” explained Jenkins.
Quadski’s transition from a rear-wheel-drive land cruiser into a personal watercraft vehicle occurs in less than five seconds. “You just drive straight into the water. As soon as you feel the vehicle floating, you hold the hand brake and press one button to retract the wheels. An electric motor actuates the coil-over-shock unit to pull the front and rear wishbone suspensions up and out of the water,” explained Jenkins.
Once in the water, the vehicle’s patented jet propulsion system draws water into a jet pump intake located in the bottom of the hull at the rear. As water leaves the intake system, it flows into an engine-driven impeller.
“This adds kinetic energy to the water as well as developing some thrust. The water then goes through a stator to recover any rotational energy in the water. That means a collimated stream of water enters the nozzle,” Jenkins said, explaining the process for increasing the water’s flow rate.
Steering commands from the driver are channeled to a steering nozzle that deflects the water flow left or right to turn the Quadski. The suspension geometry’s over-center lock fixes the wheels in position during the water-to-land transition, and the BMW engine is the power-provider.
A team of 45 engineers and technicians have been Quadski’s core development team for the last two years.
“With the Quadski and all the other products we’re developing, it is a whole different set of rules. The engineering team doesn’t have anybody to copy. Nobody’s written the playbook. So every day there are new challenges. And every day we think, ‘that was the hardest challenge.’ But it was only the hardest challenge up to that point,” Jenkins said.
Gibbs workers will assemble the Quadski at a 54,000-ft² (5017-m²) facility in Auburn Hills, MI. The first 1000 units will be sold exclusively at U.S.-based retailers, with overseas sales possible in 2014.
While the $40,000-priced Quadski is the first commercially available high-speed amphibian vehicle, Alan Gibbs, the company’s Founder and Chief Strategy Officer, said others are in the development pipeline.
“We have developed nine different proof-of-concept high-speed amphibians,” said Gibbs. The next land-water vehicles likely headed for commercial production are the 22-ft (6.7-m) Humdinga and the 30-ft (9.1-m) Phibian. Both vehicles are targeted for first responder and military applications.