Airworthiness Directives; 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

The FAA is revising an existing airworthiness directive (AD), that is applicable to 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 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 requires a onetime 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 AD requires the same actions, and includes the use of other equivalent FAA-approved serviceable bolts and washers. This 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 or other equivalent FAA-approved serviceable bolts and washers, to the engine flange, as instructed in the compliance section of this AD. We are issuing this AD to preclude propeller attaching bolt failures or improperly secured propellers, which could lead to separation of the propeller from the airplane.