The Benefits of a Glacier Bay Boat
A discussion with Larry Graf, principal and designer of Glacier Bay, Inc.
Q. What makes the Glacier Bays ride better than V-bottom boats or other catamarans?
R. V-bottom boats and most catamarans must come up on plane. Basically the hulls lift up on to the water's surface as speeds move past 12 to 15 mph (planing). Boats that must plane to move at higher speeds will always be affected by the shape of the surface they are planing over (e.g> waves, swells, chop). The twin slim hull design of the Glacier Bay never rises up on plane, at rest or full speed - the main support for the hull is buoyancy. This design feature allows the boat to slip through the waves with a limited effect on the boat. As taller waves work along the hulls, they simply move the mean water line higher and the boat rises. There are no big jarring impacts, bouncing, or pounding in most sea conditions and speeds.Q. How does the Glacier Bay compare to other catamarans on the market?
R. In general, the other catamarans on the market are good boats. They all ride much better than comparable V-bottom boats and the construction systems are on par with industry averages. However, our mission at Glacier Bay is not average. Our goal is to build vary high quality fishing boats that truly function at 100%. They must look and function great not only the first year, but also at year 5 and 10. Additionally, we want to prevent the hassles, frustrations and "bad days" on the water, leaving more fun for our customers.
On a nuts and bolts comparison, I ask buyers to pay special attention to the following areas when they compare catamarans:A. The type of gelcoat - is it UV stabilized high quality or do the company's older boats seem to dull and chalk quickly?
Q. Is the boat trailerable? How easily?
B. Is the laminating resin a strong Vinylester and Isothalic type, or a much less costly general purpose Ortholthalic type?
C. Have the hulls been hand laid with rolled mat, woven roving fabrics, Kevlar and Knitted Biaxial fabrics, or gun chopped with some roving added?
D. Is the wood stiffening in the boat a marine grade that's been specially treated so it can be guaranteed not to degrade for 10 years? Or is it regular CDX you can buy at the local lumberyard?
E. Is the visible fit and finish clean, crisp, and professional? Or is it dull and less than you'd like to show your friends?
F. Is the difficult-to-see fit and finish professionally done?
G. How are the hull and deck joined together? Is it urethane-bonded and then through-bolted and nylock-nutted every 6", or bolted in just the visible areas and riveted or screwed everywhere else?
H. Is there a fully integrated rib, stringer and bulkhead system solidly glassed in place to carry the unique catamaran loads?
R. Yes, in all 50 states the highway width limit is 8'6" or more; many states are 9 feet. Our beam is 8'6". Because of the basic tunnel shape of a Glacier Bay hull, the boats have very low aerodynamic drag and tow quite easily. Launching and retrieving is also a simple process - the pre-engineered trailer has load guides, a tall winch stand, steps, and forward loading rollers.Q. What engines are best for each model?
R. This is a big and somewhat difficult question, but everyone asks it. Here's some input for each model:202 Center Console
Q. What's the fuel capacity and range of the boats?
I like Yamaha 60-70, Suzuki 65, Johnson Evinrude 70 and Tohatsu 60-70. Engine shaft lengths are 20".
220 Center Console
Yamaha 70-90, Suzuki 85, Tohatsu 70-90 and Johnson Evinrude 60 degree V-4 90's. The new Honda 90's require a modified transom and fuel tank placement to offset the increased motor weight. Engine shaft lengths are 20".
252 Cuddy
Many owners purchase these boats with Yamaha V-4 115s or 130s and are very satisfied. Other engines I like are the Suzuki 85-115 and the Evinrude Johnson 90-115. Engine shaft lengths must be 25".
260 Center Console
Our prototype boat was run with Suzuki in line 4 cylinder 140s with very gratifying results. If your into speed, the boat's maximum rating is twin 150's which are typically V-6. However, the new 260 hull shape is more efficient, and I think the typical customer would be very satisfied with the performance of twin 115s, 130s or 140s. Honda 90s also look very promising; their fuel economy combined with minimum smoke and noise will appeal to a number of customers. In general, be advised that some of the engines in this horse power range are older designs which tend to be larger and heavier. Engine shafts are 25".
R. Listed below are the standard and optional tanks for the various models. Many customers would like to have fuel tanks to large they could go halfway to China and back. From an engineering point of view, fuel is typically the heaviest cargo on board. My goal here is to give you the maximum amount of fuel possible while still keeping the boats' seahandling ability at 100% when you have your other gear anf guests on board. I think when you compare the estimated ranges of a Glacier Bay to almost any other boat in its class, we can go farther. I've listed the estimated maximum and average range for each model. Actual range could be less depending on weather, sea conditions and engine prop condition.RANGE
Average Maximum Miles Miles 202 Center Console Johnson 70s at 26 mph Standard, twin 25 gallon tanks 130 165 Long range, twin 35 gallon tanks 182 227 220 Center Console Suzuki 85s at 26 mph Standard, twin 35 gallon tanks 175 210 Long range, twin 50 gallon tanks 250 310 252 Cuddy Johnson 115s at 26 mph Standard, twin 50 gallon tanks 185 205 Long range, twin 65 gallon tanks 234 286 260 Center Console Suzuki 140s at 35 mph Standard, twin 90 gallon tanks 240 360 Long range, w/40 gallon auxiliary 330 480Q. Why is the fuel economy better and horsepower requirements lower for catamarans?
R. There are two factors that provide the non-planing design's performance. The first is the hull shape's small wave-making ability. Moving water aside is a very big part of the energy required to push a boat. The patented Glacier Bay hull shape opens the water very easily at the bow and closes it back on itself at the stern. The effectiveness of this design can be seen when you compare the size of our wake to that of a V-bottom boat. A Glacier Bay 252 at full speed has a 4"-5" wake; V-bottom boats in this size rarely have wakes smaller than 12" and are generally 14"-16" high. Moving less water costs less money. The other factor is the energy required to lift and hold planing boats on plane. With a displacement hull, 100% fo your fuel and horsepower is applied to moving you down bay.Q. How thick are the hulls?
R. Our hulls are heavy duty compared to most, tunnel sections on the 252 and 260 are 1" thick. They are cored with 1/2" PVC rigid foam. However, the actual thickness of a laminate is not quite as important as what's actually there. Is it 1/2" thick from a resin rich chopper gun or 1/2" thick from multiple layers of hand laid mat and woven roving? Thick chop will be heavy and brittle. Layered mat and roving will be very tough and strong. So to answer the question, we have five layers each of knitted fabric and mat in the bottom of the 252 and 260, building a thickness of 1/2" to 5/8". On the 220 we have three layers each of knitted fabrics and mat, building a thickness of 3/8" to 1/2". (Some builders use only one layer of roving!)Q. Are the hulls cored below the water line?
R. I have several dealers ranging from southeast Alaska to Hawaii who will not buy boats which are cored below the water line, or any boat cored with balsa. Glacier Bay boats are solid glass below the water line. Coring with PVC foam above the water line works well, giving you a great deal of strength and stiffness. But below the water line, where you sometimes have water on both sides of the laminate with multiple freeze/thaw cycles per year as in Alaska, or warm tropical humidity, there can be laminate problems.Q. Have you ever had hull fractures?
R. None in our entire history.Q. Why use wood in the boats?
R. Wood has received a bad rap in some boats because some builders selected inferior wood. All wood is not created equal. Some varieties, like Alaskan Yellow Cedar and Northwest Fir, have excellent strength characteristics and very reasonable weights while being very resistant to degeneration, especially if treated with marine grade XL10 as we use. I like the redundancy in strength that good marine woods give you. With some of the foam systems we're seeing now, the builders are counting on 6 to 15 pound density foam cores combined with laminates to take the vibration and torque load of twin 150 hp engines. If the complete manufacturing process is done exactly as engineered, this should work. But I don't like the number of manufacturing variables in these high load foam systems. Just a note on cost - real marine woods cost about the same as foam cores, so we're not using wood to save money.Q. What are the negatives of a catamaran?
R. There are a few, but cost is probably the first. That's because the basic hull shape is so much larger (typically 65% more hull surface for the same length). Next would be the way the boat feels to an experienced V-bottom boater as it turns. Cats go around flat or actually lean slightly outboard in fast, sharp turns. The sensation is much like a car turning, which is unusual on the water. The final negative, and its rare, is that catamarans can lose their smooth riding characteristics if the boats are grossly overloaded.Q. Who designed the hull? Is it an Australian design?
R. It's my design with U.S. patents issued in 1991 and developed in the Northwest with a number of scale models and full scale engineering boats. Australian boats of this size are designed to plane, limiting how soft the ride may be. Planing boats also throw a good deal more spray underway than a Glacier Bay.Q. Do you have a stern drive model?
R. Stern drives have cast iron automotive engines which are too heavy for the stern of a trailerable catamaran. The hull shape would perform poorly with two 800 pound engines in the stern. Also, in heavy continuous saltwater use they seem to be short-lived.Q. Why have twins? Single engines cost less?
R. Our original production boat had a single engine. It was a major engineering task to get the boat's performance to meet expectations. The difficulty was the inconsistency of the water running between the hulls which creates excessive turbulence on a single engine propeller. We solved that problem, but then found that our customers really wanted a twin engine design. Most Glacier Bay owners are all-weather, go anywhere types who want the comfortable feeling of a big, get home engine. Should a problem develop, they want to come home at 20+ mph. We even set up the fuel and battery systems to be totally independent, so a problem with one engine will not affect the other.
Members of:
Marine Trades Association of New Jersey and
Yacht Architects & Brokers Association