The New Kiwi Feather Prop
Unique new composite feathering
propeller for yachts
HOW IT WORKS
When sailing, each blade is free to weather
vane into the unique and constantly varying water flow. The near
neutral buoyancy of the Zytel allows an immediate response to any
change in direction. With each blade correctly feathered and the
shaft free to rotate, the absence of any autorotation is proof of
the fully feathered status of the unit.
When motoring ahead, as the propeller starts to rotate, the
blades weather vane around to the pitch stop, where they are then
held in the preset pitch position to generate forward thrust. Upon
disengaging the motor, the unit automatically reverts to the sailing
status described above.
When reverse is engaged, the blade carrying assembly feels the
torque from the water. This winds up the internal spring, thus
allowing the small rollers on the mushroom end to force and lock
each blade back to the ahead position. The whole unit then starts to
rotate in reverse and effectively operates as a fixed three bladed
unit, thus delivering optimal reversing performance. At the end of
the reversing cycle, the spring returns the unit to the normal
These units have now been tested and developed over many years in
real life situations in Auckland, home of the America’s Cup, where
they are fast becoming the propeller of choice. They are now
available to yacht owners everywhere with the direct customer access
that the internet and international air courier facilities
The Kiwi Feather Prop brings a truly innovative set of values to
yacht owners and designers striving to get the very best all round
motoring, reversing, and sailing performance for their
Aligns feathered blades with
water flow, not the shaft.
Patented Feature: Blades free to trail like weather vanes.
Feathered propeller does not
auto-rotate. Eliminates shaft
Full pitch immediately in reverse. Compensates for the higher reduction ratios
gearboxes utilize in reverse to provide maximum
stress design without highly
Fail safe design features built around
composite blades and nose cone which minimize corrosion and
Hi-tech Zytel blades give strength and light weight with low inertia and no shock loading.
Easy to replace and lubricate but well locked in against blade
Near neutral buoyancy means blades are responsive to the
smallest changes in water flow thus always minimizing drag when
Blades pivot over cast stub shafts, not cantilevered from washer type bearings with very high stress
Eliminating the gearing allows the economical production
of 3-bladed units which are more
efficient and smoother running.
Easy pitch adjustment
with self locking set screws in
each blade allows optimal performance adjustment and eliminates
Common boss accommodates all standard shafts and Saildrives.
here for SAE taper information