After decades of work, the prototype for an innovative boat that could provide a faster, more efficient way of travel is about to be completed in Powell River’s own backyard.
Brothers Bill and Graham Cocksedge worked on the idea for years under their self-formed company, Slipstream Vehicles Ltd. Now, they are almost ready to put their 13-metre test craft on the water.
The trimaran, or three-hulled vessel, uses the patented thrust-cushion vehicle (TCV) concept.
A large enclosed fan sits at the bow of the boat. As the fan turns, it pulls air over the bow, under the floor and down through the tunnels formed by the three hulls.
The pressure created by this air flow, which acts like a slipstream, lifts the boat completely out of the water. This allows the craft to glide across the waves with little drag, increasing its efficiency. It also ensures the craft creates little to no wake.
The air used to lift the boat is also used to power it. After travelling the length of the hull, it is funnelled out the back, under the stern plates, creating a high-speed jet that propels the vessel.
“The energy you use to lift the craft comes back as thrust,” explained Bill. This, he said, differentiates the vehicle from a hovercraft, which needs one system to create lift and another to propel itself. In fact, other than being air supported, the vehicle is totally unlike hovercraft in concept and performance.
The stern plates at the end of the two slipstreams are controlled by the craft’s operator. The more open they are, the faster the vehicle goes. Turning is achieved by opening one stern plate and closing the other. This allows for sharp, precise, banked turns as opposed to the drifting of hovercraft vessels. The operator has full control over how much the hulls are submerged into the water at any time, to best suit prevailing conditions.
“We can follow a speed boat around with this one,” said Graham. “It’s a lot of fun.”
Since it is powered and cushioned by air, the craft doesn’t actually need water to move. It can traverse any relatively flat, predictable surface, ranging from mud to grass to snow.
The idea originally came from the pair’s father, who developed it in the 1960s. “He was way ahead of his time,” said Bill.
Graham agreed. “I had to do a master’s thesis in mechanical engineering to realize just how good this design was.”
The three worked on the concept as a family project, developing 4.5-, 5.5- and 10-metre test crafts. Footage from the crafts shows them gliding effortlessly around on both water and grass.
The crafts never went beyond the test stages though. “Our dad decided to move on to other things, but we continued to think about it over the decades,” said Bill.
He and his brother picked up the tools to start working on the project again some 40 years later, after they had gone through their respective careers. “We had a chance to jump back into it, so that’s what we did,” said Bill.
Before they started building the current prototype, Transport Canada assessed the concept and decided to partially fund research study into the craft’s development.
“They came back with the conclusion that yes, it’s much more efficient than anything else that’s trying to do the same thing,” said Bill.
In addition, University of British Columbia, through federal grants, is working on fan optimization for future designs.
Volunteers have been key in the process. “We have been very grateful for the wonderful help from volunteers who have been doing everything from fibreglass, electrical, graphic design and business development, filming and media information,” Bill said.
Once the 13-metre prototype is on the water, the brothers will gather hard data about how it runs. They are working with an engineering firm in Vancouver which has built a virtual model of the craft. “We can feed these hard numbers into the virtual model, which calibrates that model so we can use that to design any size we need,” explained Bill.
The brothers are looking to have the first commercial prototype finished in 2015. According to current plans, the commercial boat will be 32-metres long, carry 180 to 200 passengers, and have a cruise speed of 60 knots, or 100 kilometres per hour. This type of high-speed craft will be suited to carrying passengers or high-value cargo.
The brothers have been working with international shipping classification firm Lloyd’s Register. Bill and Graham said the company is very supportive of the concept moving forward. “If we were to build a large commercial craft, they would work with us to have it classed,” Bill explained. “That’s very important because it opens up export markets.”
With current trends, the TCV could be produced for the same price as a conventional high-speed catamaran, but will have twice the work capacity due to operating at twice the speed.
The low amount of power needed to run the vehicle’s fans translates into incredible savings in energy costs. Using data gathered from their various test crafts, the brothers have compared a 32-metre hybrid version of their vehicle to the current standard in high-speed marine travel, a foil-assisted catamaran. The Slipstream could offer more than a 60 per cent saving in fuel costs, along with faster travel times and a smoother ride, making this a very attractive package to operators.
Bill and Graham said that even though the current calculations will be improved, past testing shows significant savings are possible for TCV operators.
The extremely low energy requirements of the vehicle make electric power a viable option. “Green normally has an extra cost associated with it, but we disprove that,” said Bill. Even hybrid and diesel engines would provide a monumental reduction in emissions.
“If you are going to have high-speed marine travel—which there is a pent-up demand for around the world—it has to be efficient, it has to be manoeuvrable and it has to be fast,” said Graham. “There really isn’t anything out there that has all of those things together, and this has the potential to meet those market requirements. It has the potential to create opportunities in Powell River and BC, which encourages us.”
