Navik
NOTE: AS OF FEBRUARY 1, 2006, WE REGRET THAT SCANMAR NO LONGER SELLS OR SERVICES NAVIK PRODUCTS. PLEASE CONTACT US FOR A CONSULTATION ABOUT WHICH OF OUR PRODUCTS CAN BEST SERVE YOUR SELF-STEERING NEEDS.
Introduction
The perfect windvane for light displacement boats up to 30' LOA
An Impressive Record
In April, 1984, Gigi (a Contessa 32 sloop) sailed in under the Golden Gate Bridge after successfully retracing the path of the Clipper ships of the 1800's from New York to San Francisco. Gigi is supposedly the smallest yacht to have rounded Cape Horn from the East to the West. A vane gear kept the boat on course from New York to California.
By now several thousand systems have been sold and many circumnavigations and ocean passages have been completed with the steering the way. The sail around Cape Horn is one spectacular voyage of many.
In single-handed or shorthanded racing, the has always been the preferred choice for smaller yachts. Nearly 90% of the participants in the Mini TransAtlantic Race have been sailing with vane gears. In 1980 the race was won in record time by Californian Norton Smith on American Express using a . A steered the winning boat in the Jester class in the 1980 OSTAR (Observer Single-handed TransAtlantic Race). A vane gear was chosen by Guy Bernardin for his 38' entry in the BOC single-handed around the world race (1982-83) and steered his boat through some of the worst weather areas of all.
A steered the winner of Class IV in the 1984 OSTAR and a was used by Mark Rudiger, overall winner of the 1984 Singlehanded TransPac, on his 29' Shadowfox.
Even if you are not a singlehanded racer it is reassuring to know that your self steering has proven itself again and again on hard testing grounds.
How the Navik works
The self-steering is a development of the servo-pendulum windvane principle. In a servo-pendulum gear the windvane controls an oar, suspended in a frame on the stern of the yacht. The oar is linked by lines to the boat's own steering. With the boat on course the operator turns the windvane into the wind and engages the lines from the oar to the boat's steering.
As long as the boat is sailing on course, with the windvane pointing into the wind, the oar in the water will be lined up on the center line of the boat. If the boat gets off course the change in wind direction produces a signal from the windvane, which rotates the blade of the so called servo-pendulum oar. The pressure from the water hitting the blade face on forces the oar to swing to the side. In this way a lot of force is generated by the boat's own speed through the water. As the servo-pendulum oar is connected to the boat's own steering, the movement of the oar produces a movement of the boats rudder, which steers the yacht back on course.
Daniel Hays and his father sailed the Vertue 25 shown below from Connecticut around Cape Horn and back. They wrote a book called "My Old Man and the Sea" which made the New York Times Bestseller List.
Boats and Steering Systems
The vane gear is especially designed for smaller and medium sized boats up to 30' LOA. For boats within this limit the develops ample power to steer, while its low mounted weight and relatively small surface areas reduce stress and vulnerability.It is often assumed that a servo-pendulum gear like the is only suitable for tiller steered boats. Actually, the steers through wheel steering just as well, using a small adaptor drum on the wheel. In fact wheel steering often offers both more convenient operations and more convenient installation of the steering lines.
Special Features
Unique Double Servo System Like other vane gears of its type, the differs in one important respect: The windvane sensor does not govern the servo-oar directly. Instead the windvane is connected to a small trim-tab on the trailing edge of the servo-oar. The oar in turn is a servo-device for turning the boat's main rudder. This unique double servo system has the effect of increasing the sensitivity of the vane gear, allowing it to operate better and under conditions when other self-steering systems do not work.
Weight and Materials of Construction
The frame, supports, vane mast and paddle shaft of the are fabricated with heliarc welded stainless steel. The windvane, turret, control mechanism and linkages are made from injection molded lexan. These high quality materials provide great strength and low weight, little wear and absence of corrosion. The installed weight of a vane gear is only 30 lbs. This low weight is especially important on smaller yachts and boats of light displacement.
Safety Features
When not in use the servo-paddle of the can be removed from the water and either stored on the windvane mast or inside the boat. Paddle removal is easy and fast and protects the gear when powering, at anchor or in bad weather.
The paddle shaft and paddle are further safeguarded by an overload kick-out mechanism, which will release the servo-oar if, for example, an object is struck in the water. In a few moments the oar can be reset and the gear is ready for use again.
Installation
The vane gear attaches to the hull through two upper tubes, which are extensions of the stainless main frame, and two lower staying tubes. Stainless hull brackets are supplied for each attachment. The versatile system provides easy installation on counter and reverse transoms as well as canoe sterns and an average installation can usually be completed in a matter of hours.