The KiwiProp Feathering Propeller
The KiwiProp is the result of a long and careful development program that was designed to bring new levels of performance and value to the sailor who wishes to retain the known benefits of a fixed three-bladed propeller, for motoring and maneuverability, but at the same time minimize drag under all sailing conditions.
Traditionally feathering props have blades geared together to ensure that they line up with the shaft when feathered. However, the shaft rarely lines up with the water flow, thus increasing drag. With a typical inboard engine, the shaft will be angled down at 10 to 15 degrees and the hull sloping up at say 5 to 10 degrees, so the shaft maybe 15 to 25 degrees off the water flow. Hence auto-rotation and the need for shaft locks etc. Then there is 5 to 10 degrees of leeway and surging sideways in big waves.
In the KiwiProp the individual blades are free to “weather” vane in the water flow, so don’t rotate, which is proof that the blades are not fighting the water flow.
This three-bladed feathering propeller has proved much smoother and quieter in operation than the equivalent two bladers, but the big plus is holding up the boat speed in rough weather against the wind, enabling a quicker journey home or to shelter.
Benefits of the KiwiProp
- The Kiwi Feather Prop delivers maximum thrust in both forward and reverse from its three large blades
- Zytel, a modern DuPont composite, as used in large outboard propellers, minimizes corrosion problems
- As each individual blade is free to pivot when sailing, each blade is individually aligned with the ever changing water flow brought about by the movement of the boat and the differing installed shaft angles. Drag is minimized. There is no need for a shaft lock to prevent auto-rotation as is common in geared propellers
- Fits all Saildrives, plus industry standard 1 and 1.25 inch shafts
- The light weight Zytel blades and hydrodynamic blade tips provide for very smooth running at all speeds
- Simple pitch adjustment, available in left and right handed rotations. Suitable for 15 to 50 horsepower
- Reverse thrust equals forward thrust for maximum maneuverability
- Static thrust exceeds 425 lbs for 16 inch propeller at 1100 shaft rpm
For full specifications, visit the KiwiProps website
The KiwiProp is a simple, new solution to the low resistance, feathering yacht propeller, that really does align the blades with the water flow, not with the shaft, thus ensuring maximum sailing performance.
|Type||3 blades. Left or right hand rotation|
|Diameter||16” (406mm) and 18” (457mm)
Plastic blades easily trimmed to 15”, 17” or intermediate diameters
|Pitch Range Degrees||16 degrees to 23 degrees. Reverse 24 degrees|
|10” to 15” for 16” prop
11” to 17” for 18” prop
|Castings||316 Stainless steel|
|Blades||Dupont Zytel Black|
|Nose Cone||Dupont Delrin (Acetal) nose cone|
|Spring & Cap Screws||Stainless steel|
|Blade Retaining Pins||Titanium|
|Shaft Diameters||1.25”, 1-1/8″ and 1” plus 25mm and 30mm metric or SAE 16/32 Spline for all Saildrives|
|Shaft Taper||SAE taper per ft = 0.7500 in +/- 0.002 (1/16” per inch)|
|Shaft Nut Thread||As requested. Saildrive standard stainless steel|
|Keyway||1/4” square, parallel key|
|Maximum Power||55 hp|