Trekker Performance


	Trekkers are the World's Highest Performance Passage Makers

Performance By Design Trekker’s innovative adventure class profile is driving new performance criteria: • Environmental leadership is a key to the design and construction of every Trekker; from the careful selection of building materials that are renewable and recyclable, to the world’s highest performance displacement hull design and smart power systems, Trekker’s promise is to leave the smallest environmental wake, and help to promote the most responsible way to explore and preserve our water world. • Innovation is the heart of Trekker. Nothing looks like or performs like a Trekker yacht – inside or out. And around each and every corner in its unique design is another good idea. At Trekker Marine Enterprises, we constantly challenge every notion and assumption to explore ways to add value as well as new and improved function. • Adventure profile measures a boat’s “can-do” list, and Trekker’s aggressive new profile is optimized just for this. Incredible new opportunities to explore and enjoy our world are now possible because of Trekker’s unmatched adventure profile.

		Taken together, Trekker’s combined performance capability establishes the highest and best performance criteria for adventure class operation. Hull Form Pat Bray of Bray Yacht Design And Research is Trekker’s exclusive naval architect. Pat’s 50 years as a lifetime boater, and 25 years as a respected naval architect has provided the ideal professional background to help Trekker accomplish its mission as “the World’s highest performance passage maker.” Having spent his entire life in British Columbia, and accomplishing over 100 unique vessel designs, Pat has completed an exceptionally diverse range of projects. Especially unique is Pat’s passion for subjecting his designs to research and testing procedures. Lucky for Pat (and for us) he grew up near the highly-regarded B.C. Research - Ocean Engineering Centre. This easy access and Pat’s constant curiosity and interest in perfecting his designs has produced a distinctive capability in designing the highest performance characteristics into his hull forms. In Pat’s own words, his overview of the Trekker hull form: “The Trekker hull form is a product of our ongoing research to create extremely seaworthy yachts with super fuel-efficient characteristics and has been used successfully on many of our ocean trawlers. All Trekkers are designed to meet or exceed the ABS Rules for Unrestricted Offshore Use, and this hull’s long range of stability along with carefully thought-out design features contribute to Trekker’s ultimate extreme level of survivability.” “This super fuel-efficient hull form has been developed over 11 years of extensive research and numerous model test programs. Used on a range of our custom designs from 47’-105’, the hull characteristics have been fine-tuned - including the frequent input from our clients after many miles of open water cruising.” “Practical experience has proven that these yachts are 30% more efficient than most vessels over a wide range of displacement and semi-displacement speeds. What is more, the hull form has superior dampened sea motions, both pitching and rolling. The wide spray knockers keep water off the decks and help the bow to rise above the seas. The chined hull form has become a trademark style for us, and has a range of stability in excess of 160 degrees, making the vessel virtually self-righting at all angles of heel. By ensuring that this hull has no major downflooding points which could potentially let in water at low angles of heel, we effectively maintain this capability.” “A considerable amount of our research and development work has been focused on the fine-tuning of hull appendages. A major contributor to performance is our specific bulbous bow form. It has been fine-tuned and fitted to over 40 boats from 40’ – 160’ in length. Our present most-advanced version gives close to 14% drop in resistance and dramatically reduces pitching motions. We have also perfected the shape to prevent slapping and pounding which is a common problem with crude bulb designs.” “We also utilize a specialized wing shape under the propeller. Called the “Bi-foil Skeg,” it gives 10% greater power efficiency and further reduced pitching. This appendage also fully protects the propeller.” “Lastly, our fixed/active stabilizer fins give enhanced stability under way and at rest, while protecting the active flap from damage, dampening roll even at anchor, and when fitted with hull blisters reduce resistance a further 6%.” “It is not surprising that before becoming owners of these yachts, people have a hard time giving credibility to our fuel consumption figures. Once they take their yacht to sea however, they are thrilled with the resultant reduction in pitching provided by these features, as well as the ability of the vessel to run comfortably at 9 knots in the open ocean while burning only 1 gallon per mile.” “This hull technology has been ocean tested from Alaska to the Gulf of Mexico and Ft. Lauderdale to Annapolis; I invite you to check out Trekker’s outstanding performance pedigree for yourself. With rising fuel costs and increasingly important environmental considerations, Trekker’s new class of vessel is establishing a new benchmark.” Patrick J. Bray Naval Architect Model Testing All Trekker hulls designs are model tested at the BC Research – Ocean Engineering Centre – now run by Vizon SciTec. Here is a look at two close-up photographs during the testing procedures. Note the speeds vs. the relatively small bow and stern waves. This is one of the true tests of a hull’s efficiency – and you will seldom find a displacement hull form that moves through the water this smoothly leaving a minimal wake. Here is a quote from the test report: "Model Resistance Tests were run in the towing tank at the Ocean Engineering Centre of Vizon SciTec (formerly B.C. Research). The dimensions of the tow tank are 200 ft. long, 12 ft. wide with a water depth of 8 feet. The water is fresh, with corrections to salt water density being made via software algorithm.” “The model is towed from an instrumented carriage that is fitted with various sensors, sensor signal conditioners and a computer data acquisition system. The model is towed down the centerline of the tank with a heave bracket that is attached amidships. This system provides freedom for the model to pitch and heave but restrains it in the yaw, surge and sway modes.” “For these tests, the model was towed in calm water at constant scale speeds. Model resistance, heave (center of gravity rise), running trim and speed for each run were logged on the computer system." Stability Curve “Typical Stability Curve” - what it all means. The two most important aspects of a stability curve are 1) the overall shape of the curve and 2) the initial stability, called “GM.” As shown in the graph here, the typical stability curve for a Trekker’s hull form displays a long range of positive righting arm. This means that at all angles of heel the vessel wants to return to upright. For many vessels this is not the case. The maximum righting force also happens at a high angle so that even at 80 degrees the vessel is working hard to return to upright. At this angle the righting force is twice that at 20 degrees. This is why the plot of the righting arm line (in red) stays positive at all angles of heel. This is all well and good for survival mode but for day to day living the GM is the important information. How stable is the vessel at the dock and on your average pleasant day outing. The GM is a number that tells you the vessels stability characteristics from zero degrees of heel. Too high a number and the vessel will have a quick, snappy roll. To low a number and the vessel will be overly tender and roll excessively. We shoot for a GM rating of 4, working in a tight range between 3 to 5 maximum. This provides increased stability and a smooth and comfortable ride offshore. We call this “reasonably stiff” – not too much and not too little. Of course, initial stability is even more important to Trekker’s adventure class profile to help with the launch and retrieval operations of all the adventure craft. The hard chine hull shape combined with the passive stabilizers work wonderfully at low to no speeds, and the bulbous bow and active stabilizers smooth over the offshore miles. It is an ideal profile for unlimited adventure. For more information on stability please read our article “Stability – What is it and how does it work?” in the MEDIA> Reference section of Trekker’s web site. Patrick J. Bray Trekker Naval Architect Sea Keeping Video Sea keeping tests are required to accurately predict dynamic performance. The water tank facility can document how a vessel behaves while underway by simulating specific ocean conditions. One of the most important tests involves demonstrating a yacht’s ability to go to weather – into the waves – and still maintain optimum hull speed. Those who have traveled offshore know how important this is to operational comfort and performance. A vessel’s ability to stay dry and make headway is a virtue. For this test, the model was towed at an equivalent 9 knots into a Seastate 5 condition – defined as an average wave height of 8.5 feet with a significant wave period of 8.25 seconds. The report specifically states: "The design exhibits no tendency to bury the bow into oncoming waves, up to sea-state 5. The bulb also appears to be damping the motion effectively in these conditions, without slamming or slapping the water surface." The following video clip, slowed to simulate actual sea conditions gives you a look at the way this test is done. Note that the rear half of the bow’s foredeck remains dry.