Ruddersafe, also known as "The Columbus Egg," has been around since 1985 and is indeed a proven invention! Below is a wonderful article about the Ruddersafe double rudder, written in ANWB Waterkampioen, the Dutch magazine for water sports enthusiasts!
BETTER STEERING WITH AN OUTBOARD MOTOR
Slowly sailing with an outboard motor can be a disaster when the boat doesn't have any other rudder. As long as outboard motors exist, inventions have been introduced to improve steering to some extent. Many of them were quite risky for the motor. A new invention, the Ruddersafe, which we tried, is safe for the motor and indeed improves steering.
Even very old outboard motors were equipped with a kind of small rudder behind the propeller. This allowed for better steering with the motor at low speed. For many, many years, outboard motor rudders based on this principle have been sold in various forms. They don't always work to the satisfaction of the motor manufacturer and, ultimately, the customer.
Those small rudders are attached to the cavitation plate of the lower unit with bolts and nuts. When sailing at high speed and suddenly giving a lot of rudder, it can happen that the small rudder breaks off under the high pressure, taking a piece of the lower unit with it. Therefore, many motor importers voided the warranty if such a small rudder was installed.
AUXILIARY RUDDER FOLDS UP AT HIGH SPEED
Folding up at speed
The Ruddersafe, an outboard motor rudder of Norwegian manufacture, is based on a different principle. This rudder consists of two blades that are positioned beside the propeller. At low speed, both blades are folded down, significantly improving steering with the outboard motor. At high speeds, the blades fold up due to water pressure and hardly affect the motor's operation. We sailed with this outboard motor rudder behind an inflatable boat. It was reasonably maneuverable, even with the motor idling. With increased speed, the blades come out of the water, allowing for all the usual maneuvers expected from the motor-boat combination.
The operation of the Ruddersafe is very straightforward: there are two flat surfaces at the front of the blades that push the blades out of the water as the speed increases. To prevent this from happening at low speed, two small springs are mounted on the pivot points, providing the necessary counterpressure. The spring tension is adjustable. The Ruddersafe is available in three sizes, depending on the boat's size. The package contains the two blades and the necessary mounting materials. With simple hand tools, anyone can install this auxiliary rudder, aided by the clear instruction booklet.
Source: ANWB Waterkampioen WK 14, 1985
Text and photos: Hans Martens
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