Mandatory Inspection of Engine Governor Motor
September 25, 2017
A Safari owner has experienced a failure of the engine governor stepper motor in flight. Fortunately, he was able to bring the aircraft safely to the ground without damage.
Inspection of the motor revealed that water had entered the small hole in the stepper motor from which the electrical wiring exits the motor. The resulting rust had begun to effectively “weld” the gears of the motor together. The pilot experienced increasing resistance over some period of time, and ultimately the stepper motor “locked up” and no longer allowed throttle movement.
Safari is exploring a number of ways to incorporate a clutch or breakaway system into the governor. In the interim, all Safari owners whose aircraft has a Safari governor should examine the governor stepper motor for signs of water damage. The wire exit location should be sealed with a silicone type, waterproof sealant.
If rust is present, the owner should replace the motor and seal the wire exit point as above.
Part of a thorough pre-flight inspection is testing the free movement of the throttle. Any resistance experienced with the governor turned off is an indication that the mechanical parts of the governor or linkage require examination and adjustment or repair before flight
If you do not have a Safari governor, this does not apply your aircraft. If you have questions, please contact the factory.
