AD 90-20-13
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | CFM International, S.A. | CFM56-3B | CFM INTERNATIONAL Models CFM56-3B-2 and CFM56-3C-1 Series Engines |
| engine | CFM International, S.A. | CFM56-3C | CFM INTERNATIONAL Models CFM56-3B-2 and CFM56-3C-1 Series Engines |
Unsafe Condition
Fan blade failure, inflight shutdown, and severe engine damage.
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Required Actions
Install fan blade dampers P/N 335-105-305-0, axial stops P/N 335-105-201-0, and bolts P/N J815PO56A in accordance with CFM56 Service Bulletin 72-494, Revision 2. Ferrying is allowed under FAR 21.197 and 21.199.
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Compliance Time
within 60 days from the effective date of this AD
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Affected Aircraft
CFM International models CFM56-3B-2 and CFM56-3C-1 series engines with fan blade P/Ns 9527N99P08, 9527M99P09, 9527M99P10, 9527M99P11, and 1285M39P01, installed in Boeing 737-300/400/500 series aircraft.
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Federal Register Abstract
Fan Module Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_90-20-13.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-20-13 Document Type: AD Final Rules Docket Number: 90-ANE-16 Subject Heading: CFM INTERNATIONAL Models CFM56-3B-2 and CFM56-3C-1 Series Engines Subject: Fan Module Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/14/1990 Make: CFM International, S.A. Model: CFM56-3B | CFM56-3C Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 90-20-13 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-ANE-16 AMENDMENT: 39-6679 AD NUMBER: 90-20-13 SUBJECT HEADING: CFM INTERNATIONAL Models CFM56-3B-2 and CFM56-3C-1 Series Engines ACTION: SUMMARY: DATES: Effective October 14, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-20-13 CFM INTERNATIONAL: Amendment 39-6679. Docket No. 90-ANE-16. Applicability: CFM56-3B-2 and CFM56-3C-1 series turbofan engines equipped with fan blade Part Numbers (P/N's) 9527N99P08, 9527M99P09, 9527M99P10, 9527M99P11, and 1285M39P01. The above noted engine models are installed in, but not limited to, the Boeing 737-300/400/500 series aircraft. Compliance: Required as indicated, unless previously accomplished. To prevent fan blade failure, inflight shutdown, and severe engine damage, accomplish the following: (a) Modify the fan module assembly by installing fan blade dampers P/N 335-105-305-0, axial stops P/N 335-105-201-0, and bolts P/N J815PO56A, in accordance with the accomplishment instructions contained in CFM56 Service Bulletin 72-494, Revision 2, dated June 18, 1990, within 60 days from the effective date of this AD. (b) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished. (c) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, and alternate method of compliance with the requirements of this AD or adjustments to the compliance schedule specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. The installation of fan blade friction dampers and associated hardware into the fan module assembly shall be done in accordance with the following CFMI document: DOCUMENT PAGE REVISION DATE CFMI SB 72-494 ALL 2 June 18, 1990 This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552 (a) and 1 CFR Part 51. Copies may be obtained from CFM International, Technical Publications Department, 1 Neumann Way, Cincinnati, Ohio 45215. Copies may be inspected at the Regional Rules Docket, Office of the Assistant Chief Council, New England Region, 12 New England Executive Park, Room 311, Burlington, Massachusetts 01803, or at the office of the Federal Register, 1100 L Street, NW, Room 8301, Washington, D.C. 20591. Amendment (39-6679, AD 90-20-13) became effective on October 14, 1990. FOOTER:
Document Text
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AD Final Rules - DRS_90-20-13.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-20-13 Document Type: AD Final Rules Docket Number: 90-ANE-16 Subject Heading: CFM INTERNATIONAL Models CFM56-3B-2 and CFM56-3C-1 Series Engines Subject: Fan Module Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/14/1990 Make: CFM International, S.A. Model: CFM56-3B | CFM56-3C Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 90-20-13 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-ANE-16 AMENDMENT: 39-6679 AD NUMBER: 90-20-13 SUBJECT HEADING: CFM INTERNATIONAL Models CFM56-3B-2 and CFM56-3C-1 Series Engines ACTION: SUMMARY: DATES: Effective October 14, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-20-13 CFM INTERNATIONAL: Amendment 39-6679. Docket No. 90-ANE-16. Applicability: CFM56-3B-2 and CFM56-3C-1 series turbofan engines equipped with fan blade Part Numbers (P/N's) 9527N99P08, 9527M99P09, 9527M99P10, 9527M99P11, and 1285M39P01. The above noted engine models are installed in, but not limited to, the Boeing 737-300/400/500 series aircraft. Compliance: Required as indicated, unless previously accomplished. To prevent fan blade failure, inflight shutdown, and severe engine damage, accomplish the following: (a) Modify the fan module assembly by installing fan blade dampers P/N 335-105-305-0, axial stops P/N 335-105-201-0, and bolts P/N J815PO56A, in accordance with the accomplishment instructions contained in CFM56 Service Bulletin 72-494, Revision 2, dated June 18, 1990, within 60 days from the effective date of this AD. (b) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished. (c) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, and alternate method of compliance with the requirements of this AD or adjustments to the compliance schedule specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. The installation of fan blade friction dampers and associated hardware into the fan module assembly shall be done in accordance with the following CFMI document: DOCUMENT PAGE REVISION DATE CFMI SB 72-494 ALL 2 June 18, 1990 This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552 (a) and 1 CFR Part 51. Copies may be obtained from CFM International, Technical Publications Department, 1 Neumann Way, Cincinnati, Ohio 45215. Copies may be inspected at the Regional Rules Docket, Office of the Assistant Chief Council, New England Region, 12 New England Executive Park, Room 311, Burlington, Massachusetts 01803, or at the office of the Federal Register, 1100 L Street, NW, Room 8301, Washington, D.C. 20591. Amendment (39-6679, AD 90-20-13) became effective on October 14, 1990. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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