We spent this afternoon on the water testing the first prototype RudderProps! We left the dock around 1:30pm under gas power and made our way across the east channel to Mercer Island. There is a 10 knot wind out of the NNW so we are looking for as much shelter as possible along the east side of the island.

Once in the lee, we tilted the Tohatsu out of the water and lowered the two rudder props. They have off the shelf fixed props on for the first test. Starting with the starboard RudderProp we brought the electric direct drive motor up to full speed. At 2.9 mph we were using just over 30 amps of power. Adding the port RudderProp brought the speed up to 3.7 mph and just under 60 amps of load. Speeds with and into the wind varied by 1/2 a knot. The motors had no problem moving our high windage boat into the stiff wind. Once we fit our custom props, we expect to easily hit the 5.75 mph target speed. The 60 amp load is well within the 80 amp capacity of our 12v on board generator and will allow us tremendous extended range in hybrid mode.

As we cruised around the lake we must have been a curious sight. Our mast was down in it’s trailering position, no sails were flying, yet our outboard was tilted up clear of the water and we were silently cruising around on this gorgeous sunny day. On board, the only sound was a very faint hum as the RudderProp motors went about their business. The loudest sound on board was the gentle splash of the water at the transom as the boat sliced through the lake. Now under sail or power, cruising aboard Allegro is a peaceful tranquil experience.

In the hour we cruised around the lake we covered 3.68 miles under electric power. The motors performed great in both forward and reverse. Docking was easy even in the strong cross wind with the two widely spaced motors.

The next task is to build the custom feathering props that allow us to use a higher pitch blade for higher top end speed on our high torque electric motors.