Airworthiness Directive · Amendment 39-9140 · Hartzell Propeller, Inc. Propellers
Hartzell Propeller, Inc. Propellers
This AD applies to Hartzell Propeller, Inc. HC-B4TN-3.
The models as the FAA's AD index lists them. The serial ranges, installed parts and exceptions are in the AD itself: read it at the FAA.
This amendment adopts a new airworthiness directive (AD) that is applicable to Hartzell Propeller Inc. Model HC-B4TN-3/T10173F(N)(B,K)-12.5 and HC-B4TN-3A/T10173F(N)(B,K)- 12.5 propellers installed on Beech A100 and A100A aircraft. This action requires an initial and repetitive inspections, and specified rework or retirement, as necessary, of the propeller hub assemblies and propeller blades. This amendment is prompted by a determination that the current hub design and blade repair limits do not adequately protect against initiation of fatigue cracks in the propeller hub arm bore and do not prevent the resonant speed of the propeller from shifting into the permitted ground idle operating range. The actions specified in this AD are intended to prevent initiation of fatigue cracks in the propeller hub arm bore and subsequent progression to failure, with departure of the hub arm and blade, that may result in loss of aircraft control.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Propellers
