The only specialised marine publication in Oceania that focuses on the maritime industry, from super yachts to small craft to large commercial ships, including coastal shipping, tugs, tow boats, barges, ferries, tourist, sport-fishing craft
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Deploying the transducer arm sent me in the direction of Bladerunner Boats". Originally when designing the boat, Kenneth wanted it to be very capable for operating in heavy seas so he used the 2B category for 200 nautical mile limit in Australia as a model. While consulting with an Australian surveyor in Adelaide he suggested that you could achieve this by using a different welding schedule with thicker stringers than what Bladerunner traditionally builds in their boats. As a result she is one of the strongest boats around for her construction size and we understand that Bladerunner have adopted this same interlocking construction method for all their new commercial boats. "We wanted a boat with a very high capacity for fuel so that it would be able to make the 200 nautical mile limit with relative ease, although the full fuel capacity will not be used unless required for designated jobs," said Kenneth. "We have 1720 litres split between four tanks with 600 port and starboard aft, 260 port and starboard for'ard, makes for a heap of petrol on board, although the majority of the time it will be only using the 2 x 600 litre tanks in the aft of the vessel." Built to a mix of both Australian 2B and New Zealand maritime safety standards, we are advised that both these standards are in Locked in the down position excess of the Canadian standard requirements and as such Knave would be given her safety approval on arrival. On stepping aboard this is one chunky work boat weighing in at 5500kg light ship, add another tonne and half of fuel and water plus an extra 500kg or so for gear and we are starting to see some serious displacement, which explains why we have twin 250hp Yamaha four stroke outboard motors with 30inch legs. The choice of outboards was simple: mainly to be able to get the best power to weight ratio, and to keep the working cockpit low and clear. Outboards also allow for a quicker turn around if one were to shit itself. Plus the price differential between petrol and diesel in Canada is minimal with petrol or gasoline tracking lower than diesel. To assist in supplying dry cool air to the outboards, they are both fitted with breather snorkels that draw air from inside the transom lockers. A strong, fully fenced boarding platform is mounted between the motors that not only allows ease of access for servicing and running repairs if required, it also doubles for diver recovery, and when working astern. Once in the cockpit the davit and side- scan sonar transducer pod dominate the starboard side. The sonar transducer pod is a masterpiece of engineering, able to be easily moved from stowed to deployed position by one man. It also doubles as a normal lifting davit for bottom sampling and the like. Once the transducer pod is deployed it is securely locked into a supporting bracket and clamped on the lower belting, meaning the vessel can operate at survey speeds of up to 12 knots. The primary survey tool is an R2sonic multi-beam connected to an Applanix wave master POSMV system. This provides heading and position, yaw, pitch and roll information. The back up for this is a Trimble hemisphere DGPS and a Maretron compass that can supply information to the boat if the equipment had to be removed for other jobs. The navigation system is a tough book computer running MaxSea that interfaces with a 12 inch Navnet 3D system. There is a Vartech military grade monitor overhead that connects to the computer as a third viewing screen. Underway, showing a clean entry 14 Professional Skipper May/June 2012 Having the boat set up like this allows the operators to be able to make sure that the survey computer and boat read the same valuable positioning and heading data. This allows for continuity of both platforms to make sure that the boat and survey equipment know where they are in relation to the world around them, and that the skipper follows the appropriate survey lines set out by the survey computer operator. Another point of interest is that they are able to import waypoints and routes through MaxSea into the Navnet 3D via excel worksheets. They can transfer entire survey grids and run them through the autopilot, although this concept will take time to truly perfect and of course at first can't really be trusted, it never-the-less is advancing technology. We have more on the electronics later. We digress, now back in the cockpit, the rest of the work deck is clear and functional. There are dive bottle racks and built-in self-draining stowage trays for when working with handy bits. A built-in auxiliary outboard motor bracket for the tender motor is fitted to port. We note that all the fuel points have sturdy locking caps over the filler caps.