Townsend 47

HULL DESIGN—The design of the Townsend 47 incorporates a number of unique features. The hull design is based on the Chincoteague skiff, a nineteenth century Chesapeake oysterman hull. This well-proven design provides a comparatively beamy and shallow displacement hull form with the virtues of stability, large load carrying capability, excellent sea keeping qualities and a comparatively small wetted surface—making it easy to drive through the water.

In order to preserve the benefits of this relatively shallow draft hull and yet achieve true passagemaker levels of ultimate stability and range the designer, Leif Knutsen, incorporated the Big Foot Keel into the oysterman hull. In the Townsend 47 the bottom of the Big Foot Keel measures a wide 28" at the vessel's midpoint. This creates an area sufficient to hold the bulk of the vessel's fuel, water, waste, batteries and ballast, not only below the waterline, but below the vessel's hull, while only marginally increasing the vessel's wetted surface and resistance. The Big Foot Keel also permits the vessel to be beached in an upright and stable position if desired.

CONSTRUCTION— The overall efficiency, speed and stability of the vessel is in part due to the Townsend 47's lightweight composite construction. The Big Foot Keel itself is solid hand laid fiberglass with vinyl ester resin. The hull below the waterline is manufactured from an epoxy matrix shell over a lightweight Core-Cell foam core with the hull above the waterline being epoxy matrix over end-grain balsa core. The longitudinal interior bulkheads are also end-grain balsa/epoxy. All panels are joined by pro-set epoxy. The result is that the entire hull and superstructure, apart from the keel, weights only 8,000 pounds.

Fully equipped and well-loaded with tanks 1\2 full, 6,500 pounds of encapsulated lead ballast, a 14 feet RIB with a 60 horsepower outboard on the boat deck, and the optional sailing rig, the Townsend 47 weighs in at 44,000 pounds. Yet it is structurally as strong or stronger than the stoutest solid fiberglass vessel. Because the Townsend 47 employs a developed surface design, the composite materials can be formed at the manufacturer, rather than on site, resulting in composites higher in quality than can generally be achieved when fabrication takes place yard. The Townsend 47's extremely favorable ballast to overall weight ratio, combined with the Big Foot Keel design, provides a vertical center of gravity only 1.28 feet above the waterline. The righting arm force increases up to 59 degrees of heel and remains positive to 119 degrees.

PERFORMANCE— With its naturally aspirated 130 horsepower John Deere engine, the Townsend 47 achieves a flank speed of approximately 10 knots using 6 gallons per hour, a midrange cruise of 8.5 knots using approximately 3.6 gallons an hour and a passage making speed of 7.5 knots at 1.8 gallons per hour. Of course, use of the opt sail rig with its Hundested controlled propeller will significantly improve performance results in favorable winds. With sails deployed the Peregrine has already achieve 8.5 knots at 950 rpm in a mild breeze!

SAIL ASSIST—The Townsend 47 was designed from the keel up to accommodate the sail-assist option, which can be seen on The Peregrine Its design precursor, the Chincoteague Skiff, was a sailing vessel and the current design retains fine sailing properties.

With a 450 square foot Genoa and 125 square foot tri-sail together with the full feathering capability of the Hundested variable pitch propeller, the vessel should make 5 or more knots in a 15 to 20 knot breeze and should be able to beat off a lee shore. The sailing rig thus becomes a viable option to the complexity, extra thru-hulls and opportunities for fouling inherent with a get home engine and drive. For other than the hard chance, you can use the sail rig for the sheer pleasure of it and to supplement the engine's power by motor sailing. By adjusting the pitch of the propeller, you can compensate for the horsepower provided by the sail while still keeping your diesel engine operating at the proper temperature. The result—put up the sail, pull back the throttle, increase the pitch on the propeller until the pyrometer reads right and cruise along with significantly better fuel economy and with your already very quiet boat running at an even quieter rpm level.

NOISE— The construction of the quietest possible boat is part of the Townsend 47 mission. The foam and balsa core construction is inherently quiet. There is a flexible coupling installed between the main engine and the shaft permitting the engine and transmission to be soft mounted, greatly reducing noise. The genset is a Fisher Panda, the quietest genset on the market, which is double soft mounted. The main engine is bedded on massive purple-heart timbers. Both the engine and the genset utilize hybrid wet/dry exhaust, combining maximum safety with maximum sound attenuation. Finally, both engines are housed in a fully insulated engine room that is further isolated from the master stateroom by the workshop. Of course, an even quieter ride can be had with the sail-assist option.

ACCOMODATIONS—The Big Foot Hull design provides its owners and guests with an excellent cruising environment. The 18' beam together with all stowage of the fuel, water, wastewater, batteries and ballast below the waterline (most of it inside the Big Foot Keel) make for an extraordinarily roomy vessel. The large engine room is accessed through a workshop. The workshop provides a built-in toolbox, vise and full standing headroom. From here you have access to many of the mechanical and electrical controls. Between the engine room and the lazarette is a 3.6' long by 14 ' wide storage compartment. The settee table comfortably seats eight, more in a pinch, alternatively it can be lowered and minimized to be used as a coffee table. The galley has room for a house-sized sink, a four-burner stove, a trash compactor, a dishwasher, breadmaker, blender, microwave and ample storage for food, pots and pans, dishes, etc. The pilothouse seats six comfortably while simultaneously allowing the captain a pilot berth and ample space to move about. The master cabin is sized and furnished for both extensive stays and live aboard situations. All companionways, passages, doorways and headroom are generously sized, with an eye to comfort, safety and practicality. The overall feel of the space is comparable to that of a vessel 8 to10 feet longer.

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TESTING— The Big Foot Hull Form that is used by the Townsend 47 has been extensively tested in real world conditions. Rather than tank testing a small balsa wood model, Bigfoot Marine built a working "proof of concept" vessel at a reduced scale. The 25 foot vessel, Shadowfax, utilizes the same hull configuration as is used by the Townsend 47. The 4,500 pound, 10 foot beam vessel achieves hull speed with its 10 horsepower* Yamaha four-stroke engine and has demonstrated extraordinary sea keeping abilities throughout the waters of the Pacific Northwest. She has successfully voyaged as far as Glacier Bay, Alaska. Some of Shadowfax's accomplishments are described in Chapter One of "Small Boat Cruising to Alaska" by Leif G. Turdahl. Shadowfax has also vividly demonstrated the close quarters handling capability of the lightweight hull.

*The 10 horsepower engine provided the same power to weight ratio that is recommended for commercial fishing vessels.

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CLICK TO VIEW SPECIFICATIONS

Peregrine

VIEW THE TOWNSEND 47 IMAGE GALLERY

Inquiries to:
Brian Nordwall,
General Manager
1000 2nd Avenue, Suite 1750
Seattle, WA 98102
tel (206) 624-5155
fax (206) 624-5930

briannordwall@gmail.com

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	Big Foot Marine Presents The Townsend 47 _________________________________________________________ hull design \| construction \| performance \| sail assist noise \| accommodations \| testing \| specifications \| image gallery _________________________________________________________ Big Foot Marine is pleased to introduce the Townsend 47 passagemaker yacht. The Townsend 47 has combined the Big Foot Hull Form and the Big Foot Keel together with composite technology to create a vessel that is roomier, more stable, nimble and fuel efficient than any passage making yacht in its class. Plus, this has been accomplished at a competitive price. The Peregrine was built in the United States from stem to stern, while utilizing the finest technology and components from around the world. For example, the genset is German-made, the variable propeller system is from Denmark, the anchor winch, windows, doors and hatches are from Canada, the sail winches are from Holland, the heating system is from Finland and the composite materials were manufactured at a state of the art facility in Australia. HULL DESIGN—The design of the Townsend 47 incorporates a number of unique features. The hull design is based on the Chincoteague skiff, a nineteenth century Chesapeake oysterman hull. This well-proven design provides a comparatively beamy and shallow displacement hull form with the virtues of stability, large load carrying capability, excellent sea keeping qualities and a comparatively small wetted surface—making it easy to drive through the water. In order to preserve the benefits of this relatively shallow draft hull and yet achieve true passagemaker levels of ultimate stability and range the designer, Leif Knutsen, incorporated the Big Foot Keel into the oysterman hull. In the Townsend 47 the bottom of the Big Foot Keel measures a wide 28" at the vessel's midpoint. This creates an area sufficient to hold the bulk of the vessel's fuel, water, waste, batteries and ballast, not only below the waterline, but below the vessel's hull, while only marginally increasing the vessel's wetted surface and resistance. The Big Foot Keel also permits the vessel to be beached in an upright and stable position if desired. [top] CONSTRUCTION— The overall efficiency, speed and stability of the vessel is in part due to the Townsend 47's lightweight composite construction. The Big Foot Keel itself is solid hand laid fiberglass with vinyl ester resin. The hull below the waterline is manufactured from an epoxy matrix shell over a lightweight Core-Cell foam core with the hull above the waterline being epoxy matrix over end-grain balsa core. The longitudinal interior bulkheads are also end-grain balsa/epoxy. All panels are joined by pro-set epoxy. The result is that the entire hull and superstructure, apart from the keel, weights only 8,000 pounds. Fully equipped and well-loaded with tanks 1\2 full, 6,500 pounds of encapsulated lead ballast, a 14 feet RIB with a 60 horsepower outboard on the boat deck, and the optional sailing rig, the Townsend 47 weighs in at 44,000 pounds. Yet it is structurally as strong or stronger than the stoutest solid fiberglass vessel. Because the Townsend 47 employs a developed surface design, the composite materials can be formed at the manufacturer, rather than on site, resulting in composites higher in quality than can generally be achieved when fabrication takes place yard. The Townsend 47's extremely favorable ballast to overall weight ratio, combined with the Big Foot Keel design, provides a vertical center of gravity only 1.28 feet above the waterline. The righting arm force increases up to 59 degrees of heel and remains positive to 119 degrees. [top] PERFORMANCE— With its naturally aspirated 130 horsepower John Deere engine, the Townsend 47 achieves a flank speed of approximately 10 knots using 6 gallons per hour, a midrange cruise of 8.5 knots using approximately 3.6 gallons an hour and a passage making speed of 7.5 knots at 1.8 gallons per hour. Of course, use of the opt sail rig with its Hundested controlled propeller will significantly improve performance results in favorable winds. With sails deployed the Peregrine has already achieve 8.5 knots at 950 rpm in a mild breeze! [top] SAIL ASSIST—The Townsend 47 was designed from the keel up to accommodate the sail-assist option, which can be seen on The Peregrine Its design precursor, the Chincoteague Skiff, was a sailing vessel and the current design retains fine sailing properties. With a 450 square foot Genoa and 125 square foot tri-sail together with the full feathering capability of the Hundested variable pitch propeller, the vessel should make 5 or more knots in a 15 to 20 knot breeze and should be able to beat off a lee shore. The sailing rig thus becomes a viable option to the complexity, extra thru-hulls and opportunities for fouling inherent with a get home engine and drive. For other than the hard chance, you can use the sail rig for the sheer pleasure of it and to supplement the engine's power by motor sailing. By adjusting the pitch of the propeller, you can compensate for the horsepower provided by the sail while still keeping your diesel engine operating at the proper temperature. The result—put up the sail, pull back the throttle, increase the pitch on the propeller until the pyrometer reads right and cruise along with significantly better fuel economy and with your already very quiet boat running at an even quieter rpm level. [top] NOISE— The construction of the quietest possible boat is part of the Townsend 47 mission. The foam and balsa core construction is inherently quiet. There is a flexible coupling installed between the main engine and the shaft permitting the engine and transmission to be soft mounted, greatly reducing noise. The genset is a Fisher Panda, the quietest genset on the market, which is double soft mounted. The main engine is bedded on massive purple-heart timbers. Both the engine and the genset utilize hybrid wet/dry exhaust, combining maximum safety with maximum sound attenuation. Finally, both engines are housed in a fully insulated engine room that is further isolated from the master stateroom by the workshop. Of course, an even quieter ride can be had with the sail-assist option. [top] ACCOMODATIONS—The Big Foot Hull design provides its owners and guests with an excellent cruising environment. The 18' beam together with all stowage of the fuel, water, wastewater, batteries and ballast below the waterline (most of it inside the Big Foot Keel) make for an extraordinarily roomy vessel. The large engine room is accessed through a workshop. The workshop provides a built-in toolbox, vise and full standing headroom. From here you have access to many of the mechanical and electrical controls. Between the engine room and the lazarette is a 3.6' long by 14 ' wide storage compartment. The settee table comfortably seats eight, more in a pinch, alternatively it can be lowered and minimized to be used as a coffee table. The galley has room for a house-sized sink, a four-burner stove, a trash compactor, a dishwasher, breadmaker, blender, microwave and ample storage for food, pots and pans, dishes, etc. The pilothouse seats six comfortably while simultaneously allowing the captain a pilot berth and ample space to move about. The master cabin is sized and furnished for both extensive stays and live aboard situations. All companionways, passages, doorways and headroom are generously sized, with an eye to comfort, safety and practicality. The overall feel of the space is comparable to that of a vessel 8 to10 feet longer. [top] TESTING— The Big Foot Hull Form that is used by the Townsend 47 has been extensively tested in real world conditions. Rather than tank testing a small balsa wood model, Bigfoot Marine built a working "proof of concept" vessel at a reduced scale. The 25 foot vessel, Shadowfax, utilizes the same hull configuration as is used by the Townsend 47. The 4,500 pound, 10 foot beam vessel achieves hull speed with its 10 horsepower* Yamaha four-stroke engine and has demonstrated extraordinary sea keeping abilities throughout the waters of the Pacific Northwest. She has successfully voyaged as far as Glacier Bay, Alaska. Some of Shadowfax's accomplishments are described in Chapter One of "Small Boat Cruising to Alaska" by Leif G. Turdahl. Shadowfax has also vividly demonstrated the close quarters handling capability of the lightweight hull. The 10 horsepower engine provided the same power to weight ratio that is recommended for commercial fishing vessels. [top] CLICK TO VIEW SPECIFICATIONS* Peregrine VIEW THE TOWNSEND 47 IMAGE GALLERY Inquiries to: Brian Nordwall, General Manager 1000 2nd Avenue, Suite 1750 Seattle, WA 98102 tel (206) 624-5155 fax (206) 624-5930 briannordwall@gmail.com hull design \| construction \| performance \| sail assist noise \| accommodations \| testing \| specifications \| image gallery [top]	The Townsend 47 Inquiries? Contact, Brian Nordwall General Manager 1000 2nd Avenue, Suite 1750 Seattle, WA 98102 tel (206) 624-5155 fax (206) 624-5930 ___________________ IMAGE GALLERY Take a tour of the Townsend 47 ___________________ The October 2004 issue of PassageMaker magazine tells the story of the Townsend 47 in a nine page spread written by Robert M. Lane.
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