Airworthiness Directive · Amendment 39-9423 · General Electric Company CF6 Series Turbofan Engines
General Electric Company CF6 Series Turbofan Engines
Superseded. A later AD replaced this one: AD 99-24-15. Comply with the one in force.
General Electric Company (GE) CF6-45/-50/-80A/- 80C2 series turbofan engines installed with High Pressure Compressor Stage 3-9 Spools, Part Numbers (P/Ns) 1333M66G01, 1333M66G03; 1333M66G07, 1333M66G09, 1781M52P01, 1781M53G01,1854M95P01, 1854M95P02, 1854M95P03, 1854M95P04, 1854M95P05, 1854M95P06; 9136M89G02, 9136M89G03, 9136M89G06, 9136M89G07, 9136M89G08, 9136M89G09, 9136M89G10, 9136M89G11, 9136M89G17, 9136M89G18, 9136M89G19, 9136M89G20, 9136M89G21, 9136M89G22, 9136M89G27, 9253M85G01, 9253M85G02, 9273M14G01, 9331M29G01, and 9380M28P05 installed on, but not limited to, Airbus A300 and A310 series, Boeing 747 and 767 series, and McDonnell Douglas DC-10 and MD-11 series aircraft. 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 (o) 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 General Electric Company (GE) CF6 series turbofan engines, that currently requires initial and repetitive ultrasonic and eddy current inspections of a certain population of high pressure compressor rotor (HPCR) stage 3-9 spools for cracks. This amendment retains the inspection requirements of the current AD, but would accelerate the inspection schedule for parts affected by the current AD, require initial and repetitive inspections of an expanded population of HPCR stage 3-9 spools installed on GE CF6-45/-50/-80A engines, include HPCR stage 3-9 spools installed on GE CF6-80C2 series engines, and require reporting to the FAA the results of inspections that equal or exceed the reject criteria. This amendment is prompted by recent field experience and the associated engineering investigation, which indicate that cracks are likely to develop in a larger population of parts than previously thought. The actions specified by this AD are intended to prevent HPCR stage 3-9 spool cracking and separation, which can result in an uncontained engine failure and aircraft damage.
