Airworthiness Directive · Amendment 39-9221 · AlliedSignal Inc. (Formerly Textron Lycoming and Avco Lycoming) Model T5313B and T5317 Series Turboshaft Engines
AlliedSignal Inc. (Formerly Textron Lycoming and Avco Lycoming) Model T5313B and T5317 Series Turboshaft Engines
AlliedSignal Inc. (formerly Textron Lycoming and Avco Lycoming) Model T5313B and T5317 series turboshaft engines, installed on but not limited to Bell 205 series rotorcraft. Note: This AD applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (e) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any engine from the applicability of this AD.
This amendment supersedes an existing airworthiness directive (AD), applicable to AlliedSignal Inc. (formerly Textron Lycoming and Avco Lycoming) Model T5313B and T5317 series turboshaft engines, that currently requires initial and repetitive dye penetrant inspections of the centrifugal compressor impeller for cracks, and if necessary, removal from service. This amendment requires the use of a new, more conservative minor cycle counting factors table, introduces a method for prorating past centrifugal compressor impeller usage based on the new cycle counting factors, provides an enhanced centrifugal compressor impeller inspection procedure, and eliminates flyback criteria based on crack size. For those centrifugal compressor impellers that exceed their published life limit, this amendment implements a schedule for safe removal of time-expired parts. This amendment is prompted by a report of an uncontained centrifugal compressor impeller failure and subsequent rotorcraft accident. The actions specified by this AD are intended to prevent centrifugal compressor impeller failure, which can result in an uncontained engine failure, inflight engine shutdown, or damage to the rotorcraft.
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.
