Summary
The Federal Aviation Administration (FAA) proposes to supersede an existing airworthiness directive (AD), applicable to Textron Lycoming, direct-drive reciprocating engines (except O-145, O- 320H, O-360E, LO-360E, LTO-360E, O-435, and TIO-541 series engines). That AD currently requires inspection of the crankshaft gear installation and rework or replacement of the gears where necessary after a propeller strike, sudden stoppage, at overhaul, or whenever gear train repair is required. This proposal would revise the definitions for sudden stoppage and propeller strike. This proposal is prompted by a change to the definition of a propeller strike or sudden stoppage. The actions specified in the proposed AD are intended to prevent loosening or failure of the crankshaft gear retaining bolt, which may cause sudden engine failure.