Airworthiness Directive · Amendment 39-9979 · AlliedSignal Inc. T5311, T5313, T5317, and T53 (Military) Series Engines
AlliedSignal Inc. T5311, T5313, T5317, and T53 (Military) Series Engines
AlliedSignal Inc. (formerly Textron Lycoming) T5311, T5313, T5317, and T53 (military) series turboshaft engines, installed on but not limited to Bell Helicopter Textron 209, 205, and 204 series, and Kaman K-1200 series aircraft, and the following military aircraft: Bell Helicopter Textron AH-1 and UH-1, and Grumman OV-1 (turboprop installation), certified in accordance with Section 21.25 or 21.27 of the Federal Aviation Regulations (FAR).
This amendment adopts a new airworthiness directive (AD), applicable to AlliedSignal Inc. (formerly Textron Lycoming) T5311, T5313, T5317, and T53 series military engines approved for installation on aircraft certified in accordance with Section 21.25 of the Federal Aviation Regulations (FAR), that requires removal and replacement of the N2 spur gear nut retainer (lock cup). This amendment is prompted by reports of N2 spur gear nut retainer (lock cup) separation. The actions specified by this AD are intended to prevent N2 accessory drive assembly disengagement due to N2 spur gear nut retainer (lock cup) separation, which could result in an uncommanded engine acceleration.
