Summary
The FAA proposes to revise an existing airworthiness directive (AD) for Hartzell Propeller Inc. (formerly TRW Hartzell Propeller) models HC-B3TN-2, HC-B3TN-3, HC-B3TN-5, HC-B4TN-3, HC-B4TN-5, HC-B4MN-5, and HC-B5MP-3 turbopropellers. That AD currently requires, before further flight, that all new propellers being installed and all serviceable propellers being reinstalled, are attached using part number (P/N) B-3339 bolts and P/N A-2048-2 washers, and that the bolts are properly torqued. That AD also currently requires a one-time torque-check of P/N A-2047 bolts that are already installed through propellers and replacement of those bolts if necessary, with P/N B-3339 bolts and P/N A-2048-2 washers. This proposed AD would require the same actions. This proposed AD results from the need to make nonsubstantive wording changes and additions to clarify that terminating action is achieved by attaching propellers with P/N B-3339 bolts and P/N A-2048-2 washers to the engine flange, asinstructed in the compliance section of this AD. This proposed AD does not require an additional one-time torque-check of P/N A-2047 bolts. Also, this proposed AD does not apply to propellers installed using P/N B-3339 bolts and P/N A-2048-2 washers. We are proposing this AD to preclude propeller attaching bolt failures or improperly secured propellers, which could lead to separation of the propeller from the airplane.