Kiwiprop - SDC space requierement

Due to the hybrid nature of the design of the unit - it will occupy more space aft than a conventional feathering type propeller - and less than a conventional folding type unit.

The unit will occupy a space measured aft from the rear face of the zinc on the Saildrive to the tips of the blades in a folded / feathered or closed position of:

SDC x 2 16" Unit 310 mm or 12 1/4"

SDC x 3 18" Unit 340 mm or 13 1/2"

SDC x 4 19" Unit 340 mm or 13 1/2"

Different sized blades will alter these distances only slightly.

In addition as the pitch changes - due to the mounting of the blades, the diameter will also alter slightly. Increased pitch decreases the diameter and conversely.

This is a desirable trait as when fitting a catamaran for example where the cruise speed will be higher than a monohull - the pitch will need to be higher and a smaller diameter will partially compensate for power variances from the higher pitch.

Obviously one would allow for some clearance on top of the above figures, as the Saildrive units do move on their rubber mountings when thrust is applied.

Reverse thrust will thus require additional clearance on top of the above distances.

Remember to check clearances with the rudder hard over in the unusual situations where the rear of the propeller unit is very close to the rudder.

Generally speaking - due to the nature of Saildrive installations space will not be an issue as they are designed to accept folding propellers which will generally occupy more space aft than a comparably sized SDC unit.