AD/CFM56/30 Engine High Pressure Compressor (Cth)
AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
CFM International Turbine Engines - CFM56 Series
| AD/CFM56/30 | Engine - High Pressure Compressor | 7/2009 |
Applicability: | CFM56-5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -5B8/P, Note 1: These engines are known to be installed on, but not limited to the following aeroplane models: AIRBUS A318-111, A318-112, A319-111, A319-112, A319-115, A320-214, A320-215, A320-216, A321-111, A321-112, A321-211, A321-212 and A321-213. This AD is not applicable if engine software version 5.B.R (installed in accordance with CFM56-5B SB 73-0229) or later approved software versions are installed. |
Requirement: | 1. For engines having accumulated at the effective date of this AD 11,000 total hours or more since new or since a full High Pressure Compressor (HPC) performance restoration: a. Determine the engine Exhaust Gas Temperature (EGT) margin deterioration in accordance with CFM International SB CFM56-5B 72-0722 Revision 01. Depending on the results, apply the relevant corrective actions in accordance with Requirement 1.c. of this AD. b. Repeat the determination of the engine EGT margin deterioration, and, depending on the results, apply the relevant corrective actions in accordance with Requirement 1.c. of this AD. c. For aeroplanes where both engines indicate more than 75°C EGT margin deterioration, either remove one engine and replace it with an engine indicating less than 75°C EGT margin deterioration or install 5.B.R engine software in accordance with CFM56-5B SB 73-0229, if the engine is listed in the effectivity of CFM56-5B SB 73-0229. d. For those engines listed in the effectivity of CFM56-5B SB 73-0229, accomplish CFM56-5B SB 73-0229. The accomplishment of CFM56-5B SB 73-0229 terminates the repetitive requirements of this AD. |
| 2. For those engines listed in the effectivity of CFM56-5B SB 73-0229, having accumulated at the effective date of this AD less than 11,000 total hours since new or since a full HPC performance restoration, accomplish CFM56-5B SB 3. For those engines not listed in the effectivity of CFM56-5B SB 73-0229, having accumulated at the effective date of this AD less than 11,000 total hours since new or since a full performance restoration, accomplish the requirements and the relevant corrective actions of Requirements 1.a., 1.b. and 1.c. of this AD. 4. Do not install any CFM56-5B engine listed in the effectivity of CFM56-5B Note 2: EASA AD 2009-0088R1 dated 28 April 2009 refers. This AD supersedes EASA AD 2008-0228-E (CASA AD/A320/230). | |
Compliance: | For Requirement 1.a. - No later than 14 days from the effective date of this AD, unless previously accomplished. For Requirement 1.b. - At intervals not exceeding 800 Flight Cycles. For Requirement 1.c. - Within 30 days. For Requirement 1.d. - Within 6 months from the effective date of this AD. For Requirement 2 - Within 12 months from the effective date of this AD. For Requirement 3 - Upon accumulation of 11,000 total hours since new or since a full HPC performance restoration. For Requirement 4 - After 12 months from the effective date of this AD. |
| This Airworthiness Directive becomes effective on 2 July 2009. | |
Background: | Several in service occurrences of HPC stalls have been reported by operators of Airbus aeroplanes fitted with CFM International CFM56-5B engines since January 2007. The root cause is highly deteriorated HPCs. To improve operability and maintainability, CFM International released Engine Control Unit software 5.B.Q in January 2007 which features 2 degrees additional Variable Stator Vanes closure in the low power region to increase the stall margin. This 5.B.Q software introduction has reduced the frequency of stalls; however, since April 2008, 12 different engines with this software have experienced stalls at 3 different operators. |
| On 15 December 2008, a CFM56-5B powered Airbus A321 aeroplane experienced stalls on both engines during the same flight. This event was caused by a high level of HPC deterioration. Stalls on both engines during flight can cause a dual engine loss of thrust. AD/A320/230 applicable to CFM56-5B engines, was issued to require the EGT deterioration to be established, and for one of the engines to be replaced on aeroplanes with both engines indicating more than 80 degree Celsius (°C) of deterioration. It was subsequently deemed necessary to mandate repetitive inspections, to reduce the deterioration threshold to 75°C, and to apply additional aeroplane level operational requirements. In February 2009, CFM introduced the 5.B.R software standard (CFM56-5B SB This AD supersedes AD/A320/230, introduced limitations to the applicability, deleted aeroplane actions which were no longer necessary to prevent the identified unsafe condition and deleted redundant maintenance tasks. This AD also required the installation of 5.B.R software as a terminating action. |
James Coyne
Delegate of the Civil Aviation Safety Authority
19 May 2009
0
0
0