Airworthiness Directive · Amendment 39-12642 · Honeywell International, Inc., (Formerly AlliedSignal, Inc., and Textron Lycoming) T5311A, T5311B, T5313B, T5317A, T5317B, T53-L-11, T53-L-11A, T53-L-11B, T53-L-11C, T53-L-11D, T53-L-11A S/SA, T53-L-13B, T53-L-13B S/SA, T53-L-13B S/SB, and T53-L-703 Turboshaft Engines
Honeywell International, Inc., (Formerly AlliedSignal, Inc., and Textron Lycoming) T5311A, T5311B, T5313B, T5317A, T5317B, T53-L-11, T53-L-11A, T53-L-11B, T53-L-11C, T53-L-11D, T53-L-11A S/SA, T53-L-13B, T53-L-13B S/SA, T53-L-13B S/SB, and T53-L-703 Turboshaft Engines
Superseded. A later AD replaced this one: AD 2022-10-02. Comply with the one in force.
This airworthiness directive (AD) is applicable to Honeywell International, Inc., (formerly AlliedSignal, Inc., and Textron Lycoming) T5311A, T5311B, T5313B, T5317A, T5317B, and former military T53-L-11, T53-L-11A, T53-L-11B, T53-L-11C, T53-L-11D, T53- L-11A S/SA, T53-L-13B, T53-L-13B S/SA, T53-L-13B S/SB, and T53-L-703 turboshaft engines. These engines are installed on, but not limited to Bell Helicopter Textron 204, 205, and 209 series, and Kaman K- 1200 series helicopters, and the following surplus military helicopters that have been certified in accordance with sections 21.25 or 21.27 of the Federal Aviation Regulations (14 CFR 21.25 or 21.27): Bell Helicopter Textron manufactured AH-1, HH-43, TH-1, UH-1 and SW-204/205 (UH-1) series.
This amendment adopts a new airworthiness directive (AD), that is applicable to Honeywell International, Inc., (formerly AlliedSignal, Inc., and Textron Lycoming) T5311A, T5311B, T5313B, T5317A, T5317B, and former military T53-L-11, T53-L-11A, T53-L-11B, T53-L-11C, T53-L-11D, T53-L-11A S/SA, T53-L-13B, T53-L-13B S/SA, T53-L-13B S/SB, and T53-L- 703 series turboshaft engines. This amendment requires initial and repetitive special vibration tests of the engine, and if necessary replacement with a serviceable reduction gearbox assembly, or a serviceable engine before further flight. This amendment is prompted by reports of tachometer drive spur gear failure, resulting in potential engine overspeed, loss of power turbine speed (N2) instrument panel indication, and hard landings. The actions specified in this AD are intended to prevent excessive vibrations produced by the reduction gearbox assembly that could cause failure of the tachometer drive spur gear.
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.
