Ray Clegg - KIS CRUISER MODIFICATIONS


CESSNA 172 Electric Flap Motor Adapted to KIS Cruiser


I know electric flaps are not everyone's choice but I know Al is interested so I enclose photographs of the Cessna flap motor I have converted. You will see my Cruiser is becoming more and more Cessna but I am having great difficulty installing the high wings!!!

Modification of the Cessna flap motor is minimal. The only additional item was an end to the jack screw so that it would fit the standard Cruiser torque tube lever in place of the manual mechanism The motor is bolted to the fuselage floor via a hard point in the left baggage compartment. Because the motor is too big to fit in the tunnel the torque tube lever has to be moved to the left and then sits under the left rear seat. This does mean raising the seat slightly for clearance.

The motor has adjustable micro switches fitted so any degree of flap movement can be pre-set. In fact we have gone for only two positions 12 and 36 degrees but three would be possible.  The flap motor weighs 5lbs and the manual mechanism which was not used weighed 2lbs Therefore an overall increase in weight of the aeroplane of 3lbs.


We were concerned that the steel torque tube running in dry alloy hangers would tend to wear and there would be no alternative but to replace the hangers. To reduce wear, provide free movement and make eventual replacement relatively simple, or unnecessary we have fitted oilite bushes to the bearings. This is not a simple modification as it entails machining new hangers to take the oilite bushes. They can be seen on the exploded photograph of the motor and torque tube.

Removal of the manual flap handle allows a throttle quadrant to be fitted (no photographs at the present time).