Airworthiness Directive · Amendment 39-15779 · CFM International, S. A. CFM56-5B Series Turbofan Engines
CFM International, S. A. CFM56-5B Series Turbofan Engines
Superseded. A later AD replaced this one: AD 2010-09-14. Comply with the one in force.
This AD applies to CFM International, S. A. CFM56-5B1, -5B2, -5B4, -5B5, -5B6, -5B7, -5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -5B8/P, -5B9/P, -5B1/2P, -5B2/2P, -5B3/2P, -5B3/2P1, -5B4/2P, -5B6/2P, -5B4/P1, -5B4/2P1, and -5B9/2P turbofan engines. These engines are installed on, but not limited to, Airbus A318, A319, A320, and A321 series airplanes.
The FAA is adopting a new airworthiness directive (AD) for CFM International, S. A. CFM56-5B series turbofan engines. This AD requires reviewing exhaust gas temperature (EGT) monitoring records to determine EGT deterioration margin, and for airplanes where both engines have greater than 80[deg] centigrade (C) deterioration of EGT margin, borescope-inspecting the high-pressure compressor (HPC) of both engines. This AD also requires removing from service any engine that does not pass the borescope inspection, and if both engines pass, removing and replacing one of the engines with an engine that has 80 [deg]C or less deterioration of EGT margin. This AD also requires continuous monitoring of EGT margin on engines in service, to prevent two engines on an airplane from having greater than 80 [deg]C of deterioration of EGT margin. This AD results from an Airbus A321 airplane powered by CFM56-5B1/P turbofan engines experiencing HPC stalls during climb out after takeoff. We are issuing this AD to prevent HPC stalls, which could prevent continued safe flight or landing.
You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.
(f) Within 14 days of the effective date of this AD do the following:
(1) Review exhaust gas temperature (EGT) monitoring records to determine EGT deterioration margin.
(2) For airplanes where both engines have greater than 80° centigrade (C) deterioration of EGT margin, do the following:
(i) Borescope-inspect HPC stages 1, 3, 6, and 9 of both engines. Information on borescope inspection of the HPC can be found in the aircraft maintenance manual.
(ii) Remove from service any engine that does not pass the borescope inspection requirements found in the aircraft maintenance manual.
(iii) If both engines pass the borescope inspection, then remove one of the engines from service and replace it with an engine that has 80 °C or less deterioration of EGT margin.
(3) Continue monitoring EGT margin on engines in service, to prevent two engines on an airplane from having greater than 80 °C deterioration of EGT margin. Information on monitoring EGT can be found in CFM International, S. A. Service Bulletin (SB) No. CFM56-5B S/B 72-0722, dated December 22, 2008.
These actions are interim actions and we anticipate further rulemaking actions in the future, including further action to address the remaining engines in service that are above 80 °C deterioration of EGT margin.
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.
