Pilot Operating Handbook
Cavalon Pro
SECTION 9-1
Variable Pitch Propeller
RotorSport_POH_Cavalon Pro
Revision 1.0 – Issue Date 12 04 2015
9-1
9.1
Variable Pitch Propeller – Woodcomp KW-31
9.1.1
General
A variable pitch propeller (VPP) manufactured by Woodcomp Propellers s.r.o. of the Czech
Republic, is fitted to optimise propeller efficiency, fuel consumption and noise in all flight
regimes and power settings. This is achieved by changing the propeller pitch in flight.
The propeller is the KW-31, set up for RotorSport gyroplanes This means that there are
internal design features that make the product unique, and it must not be replaced by a
propeller other than the part supplied by RotorSport UK Ltd.
The propeller is electrically actuated via slip rings on the engine interface.
WARNING! Cleanliness of this face is important, DO NOT apply corrosion preventative
substance to the slip rings! It will prevent them from functioning!
9.1.2
Propeller Function
In this propeller the pitch change is obtained by rotating each blade in bearings at its root.
An electrical gear-motor mounted in the propeller hub drives a central boss which rotates
the blades simultaneously by means of three trunnion / pin mechanisms.
The propeller has two internal pitch limit stops, electrically and mechanically limiting the
pitch angle at the pre-determined FINE and COARSE limits.
These pre-determined limits ensure that the aircraft will still climb at a minimum rate of
250fpm in the full-COARSE setting, and will not over-rev the engine in the climb in the full-
FINE setting.
However, it is the pilots responsibility to monitor engine rpm in the
cruise and descent to ensure the engine speed is kept within operational limits!
Note that the propeller requires up to 8 secs to transit from full fine to full coarse pitch.
9.1.3
Propeller Control
Woodcomp provide an electrical constant speed controller (aka propeller governor) for use
with the KW-31 propeller and this is fitted in the centre instrument panel of the Cavalon Pro:
Day-VFR panel configuration Night-VFR configuration
Constant speed controller