Demystifying the Autoprop Sailboat Propeller
Autoprop sailboat propellers really do live up to their tag line of perfect propulsion but how do they work? When performance, maneuverability and efficiency are the driving forces for selecting a sailboat propeller, the Autoprop is in a class of its own. But how do they work? This post explains how the blades of an Autoprop sailboat propeller work to create thrust in both ahead and astern conditions and how they feather when not needed. Click on the video below to see Dr Roderick Sampson of King Propulsion explain the workings of the Autoprop sailboat propeller live in a test tank. The video shows the unique feathering and pitching of the blades as the rotation direction changes.
Bruntons Autoprop will greatly enhance the performance of a vessel both under power and under sail. What the Autoprop does is it self regulates its pitch with the speed of the boat the speed of the engine. How does it do this? Well it does this by balancing the forces acting on it to find the optimum angle of attack. This will give you more speed at less rpm and save on fuel bills.
What you see below is that when the propeller is running in the ahead and the astern position the leading edge of the blade is still leading in both directions giving you better stopping performance and better maneuverability. When under sail the Autoprop will feather taking the least line of resistance, just like a flag in the wind giving you up to half a knot speed under sail.