Robinson has issued a safety alert regarding pilot monitoring of the engine governor.
“There have been occurrences where governor malfunction was not recognized by the pilot in time to prevent an overspeed or an unsafe low RPM condition,” the alert states.
“The governor has been extremely reliable to the point that some pilots trust it without guarding against malfunction. Malfunctions can and do occur on any aircraft system and pilots need to consciously monitor system operation.”
The alert calls on pilots to monitor the governor’s operation during flight by keeping a hand lightly on the throttle twist grip. If the twist grip becomes erratic or stops altogether, the alert states that the governor may be malfunctioning.
“If [the] twist grip rotates steadily open or closed, override promptly to prevent RPM excursion,” the alert adds, cautioning not to unintentionally override the governor by squeezing the throttle grip too tightly during normal operation.
“If a governor malfunction is suspected, switch governor off and assume manual RPM control using twist grip,” the alert states.