Airworthiness Directive · Amendment 39-9529 · AlliedSignal Inc. TFE731 Series Turbofan Engines
AlliedSignal Inc. TFE731 Series Turbofan Engines
AlliedSignal Inc. (formerly Garrett Engine Division) TFE731-2, -2A, -3, -3A, -3AR, -3B, -3BR, -3C, -3CR, -3D, - 3DR, -3R, and -4R series turbofan engines with fan rotor disk part numbers (P/N's) 3072162-1 through -5, 3072816-1, -2, and -3, 3073436-1 through -5, 3073539-(All), and 3074529-(All), where (All) denotes any dash number, installed on but not limited to the following aircraft: Avions Marcel Dassault Falcon 10, 50, 100 series; Learjet 31, 35, 36, and 55 series; Lockheed-Georgia 1329-23 and -25 series; Israel Aircraft Industries 1124 and 1125 series; Cessna 650, Citations III, VI, and VII; Raytheon British Aerospace HS-125 series; and Sabreliner NA-265-65. Note: This airworthiness directive (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 (b) to request approval from the Federal Aviation Administration (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 Garrett Engine Division) TFE731 SeriesTurbofan Engines, that currently requires inspection of fan rotor disks within certain schedules. This amendment requires initial and repetitive eddy current inspections using an improved, more definitive procedure for detecting fan rotor disk dovetail slot cracks. Also, this amendment adds additional engine models and fan rotor disk part numbers and disallows fluorescent penetrant inspection (FPI) as an alternative inspection method for detecting fan rotor disk dovetail slot cracks. This amendment is prompted after additional analyses revealed that stress levels in the fan rotor disk dovetail slots for the applicable engine models are higher than initially calculated. The actions specified by this AD are intended to prevent uncontained failure of fan rotor disks due to fatigue cracking in the dovetail slots, which can result in inflight engine shutdowns, severe secondary damage, and fan rotor assembly separation from the engine.
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.
Engines
