SPACE
REQUIRED:
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 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.