Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to Dowty Aerospace Propellers R391-6- 132-F/3 series propellers. This proposal would require installation of an improved overspeed governor. This proposal is prompted by reports of overspeed governor failure. The actions specified by the proposed AD are intended to prevent overspeed governor failure, which could result in propeller overspeed, vibration, possible loss of propeller integrity, and loss of control of the airplane.