Airworthiness Directives; Dowty Aerospace Propellers Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/13 Propeller Assemblies

摘要

The FAA is superseding an existing airworthiness directive (AD) for Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4- 82-F/13 propeller assemblies. That AD currently requires initial and repetitive ultrasonic inspections of propeller hubs, part number (P/N) 660709201. This AD requires the same initial and repetitive ultrasonic inspections, but reduces the initial and repetitive compliance times for Type R334/4-82-F/13 propeller assemblies when used on Construcciones Aeronauticas, S.A. (CASA) 212 airplanes. This AD results from a report of a hub separation on a CASA 212 airplane. We are issuing this AD to prevent propeller hub failure due to cracks in the hub, which could result in loss of control of the airplane.