A folding propeller is a mechanical device mounted at the aft end of a vessel's propeller shaft. The rotation of its twisted blades creates hydrodynamic thrust, propelling the craft forward. The blades are feathered when the motor is off, reducing drag and making for a substantial increase in speed.
These propellers are found primarily on sailboats, but can be useful on the emergency back-up motors of powerboats.
Such propellers are generally made of copper-nickel, bronze, stainless steel or other alloys. Two or three articulated blades are mounted on a streamlined hub with circular rack and pinion gear. When the propeller or sail-drive shaft stops turning, water flowing over the blades folds them together, limiting drag. Velocity gain can reach one or two knots, not insignificant during a race.
Choice will depend on the nature and diameter of the transmission, be it propeller or sail-drive. Other factors include engine make, model and power, and the reduction ratio of the reversing gearbox.
- Increased speed under sail
- Slower maneuvering response
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Folding boat propeller (3 blades, shaft-drive or saildrive) Volvo Penta
Volvo Penta's 3 & 4-blade folding propellers are perfect for sailboats with minimal drag under sail combined with effective...
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Folding boat propeller (3 blades, shaft-drive or saildrive) ZINC ANODE Gori Propeller
"Overdrive" function The 3-blade Gori folding propeller's "overdrive" function adds a new dimension to sailing under power. The helmsman can choose the propeller pitch and profile in the water while sailing forward, by regulating the...
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Folding propeller for racing sailboat (2 blades) France Hélices
The SAIL PROP is manufactured so that the torque of the preadjusted pitch position. The propeller hub and the shaft are connected by level gearing which guarantees...
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Folding boat propeller (3 blades, shaft-drive or saildrive) Eliche Radice S.p.A.
Eliche Radice s.p.a has developed a new type of propeller which offers minimum resistance to forward motion while sailing and is highly efficient when under power. Starting with the traditional propeller with folding blades, a three blade model was developed which is a more efficient configuration...
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Folding propeller for racing sailboat (2 blades) Darglow Engineering Ltd.
Folding propellers have come a long way since they were first used as long ago as the 1920's! Darglow manufactured thousands of 2-bladed folding propellers in the 1970's and 80's and these were among the earliest reliable...
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Folding propeller for racing sailboat (2 blades) MARK III ELIPTEC Martec
Elegant. Sculpted. Powerful. Even more powerful performance. Our folding props deliver unparalleled performance, matching and bettering fixed two-blade props. Since1964 we have continually refined and upgraded the Martec folding prop. We have redefined the concept of low-drag sailboat propellers, creating a family of folding, feathering and fixed blade props....
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Folding propeller for racing sailboat (2 blades) SLIPSTREAM® Austral Propeller
Seahawk Australia and Austral Propellers have joined forces to bring you the "SLIPSTREAM" range of Geared Folding Sailboat Propellers. For racing and social yachts, streamlining and smoothness of design is...
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Varifold folding propellers have taken the market by storm. Regularly fitted by such notable yacht building names as Baltic, Swan, Wally, Moody and Oyster, the complete range of Varifolds has a model for cruiser racing and racing yachts...
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Folding sailboat propeller (4 blades) SPW
The VARIFOLD 4-blade propeller with a diameter of up to 920mm is the latest SPW development. Here you see the VARIFOLD mounted on the high-performance Baltic Yacht 147' with Caterpillar 710hp engine. Baltic-Yachts commissioned Bruntons...
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Boat folding propeller 2 blades, saildrive S6 Seahawk
Geared design keeps blades synchronized, allowing the blades to fold back properly regardless of the propeller position, even at low speeds. Sizes from 14" to 20" diameter All Stainless Steel construction for superior life using...
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Folding boat propeller (2 blades, plastic) Ultimo Composite Propeller
The only propeller designed and manufactured entirely on engineering...
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Folding propeller for racing sailboat (2 blades) TYPE PP hélices y Suministros Navales
2 bladed folding propellers,...
