Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to Hamilton Standard 14RF and 14SF series, and Hamilton Standard/British Aerospace Model 6/5500/F propellers. This proposal would require initial and repetitive inspections of critical components, and removal, and replacement with serviceable parts, of those critical components that do not meet the return to service criteria. This proposal is prompted by failure modes effects analysis (FMEA), certification test data, engineering analysis, and repair actions performed at overhaul depots. The actions specified by the proposed AD are intended to prevent loss of propeller control due to failure of critical components, which could result in loss of control of the aircraft.