AD 91-15-16
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | General Electric Company | CF6-45A | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-45A2 | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50A | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50C | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50C1 | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50C2 | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50C2B | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50C2D | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50CA | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50E | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50E1 | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50E2 | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
| engine | General Electric Company | CF6-50E2B | GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines |
Unsafe Condition
Cracks in high pressure turbine (HPT) thermal shields could lead to uncontained engine failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Eddy current inspect HPT thermal shields with specified part numbers before 800 cycles since last HPT overhaul or 400 cycles after AD effective date, whichever is later. Reinspect every 400 cycles. Remove cracked shields before flight and replace. Inspect HPT stage disks as per Appendix I if cracks are found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Prior to accumulating 800 cycles since last HPT overhaul or 400 cycles in service after the effective date of this AD, whichever occurs later. Thereafter, reinspect at intervals not to exceed 400 cycles since last inspection.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
General Electric Company CF6-45/-50 series engines installed on Airbus A300, Boeing 747, and McDonnell Douglas DC-10-15/DC-10-30 aircraft.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
High Pressure Turbine Thermal Shields
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-15-16.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-15-16 Document Type: AD Final Rules Docket Number: 91-ANE-01 Subject Heading: GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines Subject: High Pressure Turbine Thermal Shields Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/04/1991 Make: General Electric Company Model: CF6-45A | CF6-45A2 | CF6-50A | CF6-50C | CF6-50C1 | CF6-50C2 | CF6-50C2B | CF6-50C2D | CF6-50CA | CF...Show more 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: 91-15-16 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-ANE-01 AMENDMENT: 39-7080 AD NUMBER: 91-15-16 SUBJECT HEADING: GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines ACTION: SUMMARY: DATES: Effective September 4, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-15-16 GENERAL ELECTRIC COMPANY: Amendment 39-7080, Docket No. 91-ANE- 01. Applicability: General Electric Company (GE) CF6-45/-50 series turbofan engines, installed on, but not limited to, Airbus A300, Boeing 747, and McDonnell Douglas DC-10-15 and DC-10-30 aircraft. Compliance: Required as indicated, unless previously accomplished. To prevent uncontained engine failure, accomplish the following: (a) Eddy current inspect affected high pressure turbine (HPT) thermal shields, Part Numbers (P/N's) 9045M31P04, 9045M31P05, 9045M31P07, 9045M31P08, 9045M31P09, 9045M31P10, 9045M31P12, 9045M31P13, 9143M71P01, 9143M71P02, 9155M16P01, 9155M16P02, 9155M16P03, 9155M16P04, 9181M64P01, 9181M64P02, 9181M64P07, 9181M64P08, 9181M64P10, 9186M96P02, and 9186M96P03, in accordance with the Accomplishment Instructions contained in GE CF6-50/-45 Service Bulletin (SB) 72-879, Revision 6, dated October 30, 1990, as follows: (1) Inspect prior to accumulating 800 cycles since last HPT overhaul or 400 cycles in service after the effective date of this AD, whichever occurs later. (2) Thereafter, reinspect at intervals not to exceed 400 cycles since last inspection. (3) Remove cracked HPT thermal shields from service prior to further flight and replace with a serviceable part. (b) Affected HPT thermal shields stated in paragraph (a) of this AD, would also be assembled into one of the following HPT thermal shield assembly P/N's: 9045M53G04, 9045M53G05, 9045M53G07, 9045M53G08, 9045M53G09, 9045M53G10, 9045M53G12, 9045M53G13, 9045M53G14, 9186M78G01, 9186M78G02, 9186M78G03, 9186M78G04, 9186M78G05, 9186M78G06, 9186M78G07, 9186M78G08, 9208M76G02, 9208M76G03, and 9208M76G04. (c) For the purpose of this AD, an HPT overhaul is defined as the induction of the engine into a shop where the subsequent maintenance entails HPT disassembly. (d) The eddy current inspection requirements of paragraph (a) of this AD are not applicable to engines incorporating an affected P/N thermal shield that has operated exclusively with an interstage seal, P/N 9315M16G14, 9315M16G15, or 9315M16G17, provided the owner or operator submits to their Airworthiness Inspector the configuration documentation substantiating that the affected thermal shield has never been operated with a P/N 9045M23G07, 9045M23G08, 9045M23G09, 9045M23G10, 9045M23G11, or 9045M23G12 interstage seal. (e) Prior to further flight, remove from service HPT stage one disks which have operated in engines containing an HPT thermal shield cracked through its forward flange. These removed HPT stage one disks may not be returned to service. (f) Prior to further flight, remove from service HPT stage two disks which have operated in engines containing an HPT thermal shield cracked through its rear flange. HPT stage two disks may be returned to service if no cracks are detected when inspected in accordance with Appendix I. (g) 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. (h) Upon submission of substantiating data by an owner or operator through an FAA Inspector (maintenance, avionics, or operations, as appropriate), an alternate method of compliance with the requirements of this AD or adjustments to the compliance times specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803-5299. (i) The eddy current inspections shall be done in accordance with the following GE CF6-50/-45 SB 72-879: PAGE NO. ISSUE/REVISION DATE 3-14, 17-26, 29-31 Rev. 5 1/6/88 1, 2, 16, 28 Rev. 6 10/30/90 15, 27 Orig. 1/24/86 Total Pages: 31 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 General Electric Aircraft Engines, CF6 Distribution Clerk, Room 132, 111 Merchant Street, Cincinnati, Ohio 45246. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Room 311, Burlington, Massachusetts, or at the Office of the Federal Register, 1100 L Street, NW, Room 8401, Washington, D.C. APPENDIX I 1. Reference: CF6-50 Shop Manual Document No. GEK-50481. 2. Accomplishment Instructions: A. Clean, etch, and fluorescent penetrant inspect (FPI) the high pressure turbine rotor (HPTR) stage two disk according to Chapter 72-53-04, High Pressure Turbine Rotor Stage 2 Disks - Inspection, paragraph 2, Fluorescent - Penetrant Inspect Disk, of the reference shop manual. NOTE: The immersion ultrasonic inspection (Subtask 72-53-04-270-051) may be used in lieu of an FPI for the stage 2 disk dovetail serrations only. B. Clean, etch, and eddy current inspect (ECI) the HPTR stage two disk dovetail slot bottoms according to Chapter 72-53-04, High Pressure Turbine Rotor Stage 2 Disk- Inspection, paragraph 5, Special Inspection of Dovetail Slot Bottoms, of the reference shop manual. NOTE: If ECI capability is not available, the disk must be recleaned in accordance with paragraph 2.A (starting with Subtask 72-53-04-140-051). The slot bottoms must then be fluorescent penetrant inspected in accordance with paragraph 2.D (Subtask 72-53-04-230-001- 057) paying special attention to slot bottom corners. This amendment (39-7080, AD 91-15-16), becomes effective on September 4, 1991. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_91-15-16.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-15-16 Document Type: AD Final Rules Docket Number: 91-ANE-01 Subject Heading: GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines Subject: High Pressure Turbine Thermal Shields Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/04/1991 Make: General Electric Company Model: CF6-45A | CF6-45A2 | CF6-50A | CF6-50C | CF6-50C1 | CF6-50C2 | CF6-50C2B | CF6-50C2D | CF6-50CA | CF...Show more 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: 91-15-16 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-ANE-01 AMENDMENT: 39-7080 AD NUMBER: 91-15-16 SUBJECT HEADING: GENERAL ELECTRIC COMPANY Models CF6-45/-50 Series Engines ACTION: SUMMARY: DATES: Effective September 4, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-15-16 GENERAL ELECTRIC COMPANY: Amendment 39-7080, Docket No. 91-ANE- 01. Applicability: General Electric Company (GE) CF6-45/-50 series turbofan engines, installed on, but not limited to, Airbus A300, Boeing 747, and McDonnell Douglas DC-10-15 and DC-10-30 aircraft. Compliance: Required as indicated, unless previously accomplished. To prevent uncontained engine failure, accomplish the following: (a) Eddy current inspect affected high pressure turbine (HPT) thermal shields, Part Numbers (P/N's) 9045M31P04, 9045M31P05, 9045M31P07, 9045M31P08, 9045M31P09, 9045M31P10, 9045M31P12, 9045M31P13, 9143M71P01, 9143M71P02, 9155M16P01, 9155M16P02, 9155M16P03, 9155M16P04, 9181M64P01, 9181M64P02, 9181M64P07, 9181M64P08, 9181M64P10, 9186M96P02, and 9186M96P03, in accordance with the Accomplishment Instructions contained in GE CF6-50/-45 Service Bulletin (SB) 72-879, Revision 6, dated October 30, 1990, as follows: (1) Inspect prior to accumulating 800 cycles since last HPT overhaul or 400 cycles in service after the effective date of this AD, whichever occurs later. (2) Thereafter, reinspect at intervals not to exceed 400 cycles since last inspection. (3) Remove cracked HPT thermal shields from service prior to further flight and replace with a serviceable part. (b) Affected HPT thermal shields stated in paragraph (a) of this AD, would also be assembled into one of the following HPT thermal shield assembly P/N's: 9045M53G04, 9045M53G05, 9045M53G07, 9045M53G08, 9045M53G09, 9045M53G10, 9045M53G12, 9045M53G13, 9045M53G14, 9186M78G01, 9186M78G02, 9186M78G03, 9186M78G04, 9186M78G05, 9186M78G06, 9186M78G07, 9186M78G08, 9208M76G02, 9208M76G03, and 9208M76G04. (c) For the purpose of this AD, an HPT overhaul is defined as the induction of the engine into a shop where the subsequent maintenance entails HPT disassembly. (d) The eddy current inspection requirements of paragraph (a) of this AD are not applicable to engines incorporating an affected P/N thermal shield that has operated exclusively with an interstage seal, P/N 9315M16G14, 9315M16G15, or 9315M16G17, provided the owner or operator submits to their Airworthiness Inspector the configuration documentation substantiating that the affected thermal shield has never been operated with a P/N 9045M23G07, 9045M23G08, 9045M23G09, 9045M23G10, 9045M23G11, or 9045M23G12 interstage seal. (e) Prior to further flight, remove from service HPT stage one disks which have operated in engines containing an HPT thermal shield cracked through its forward flange. These removed HPT stage one disks may not be returned to service. (f) Prior to further flight, remove from service HPT stage two disks which have operated in engines containing an HPT thermal shield cracked through its rear flange. HPT stage two disks may be returned to service if no cracks are detected when inspected in accordance with Appendix I. (g) 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. (h) Upon submission of substantiating data by an owner or operator through an FAA Inspector (maintenance, avionics, or operations, as appropriate), an alternate method of compliance with the requirements of this AD or adjustments to the compliance times specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803-5299. (i) The eddy current inspections shall be done in accordance with the following GE CF6-50/-45 SB 72-879: PAGE NO. ISSUE/REVISION DATE 3-14, 17-26, 29-31 Rev. 5 1/6/88 1, 2, 16, 28 Rev. 6 10/30/90 15, 27 Orig. 1/24/86 Total Pages: 31 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 General Electric Aircraft Engines, CF6 Distribution Clerk, Room 132, 111 Merchant Street, Cincinnati, Ohio 45246. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Room 311, Burlington, Massachusetts, or at the Office of the Federal Register, 1100 L Street, NW, Room 8401, Washington, D.C. APPENDIX I 1. Reference: CF6-50 Shop Manual Document No. GEK-50481. 2. Accomplishment Instructions: A. Clean, etch, and fluorescent penetrant inspect (FPI) the high pressure turbine rotor (HPTR) stage two disk according to Chapter 72-53-04, High Pressure Turbine Rotor Stage 2 Disks - Inspection, paragraph 2, Fluorescent - Penetrant Inspect Disk, of the reference shop manual. NOTE: The immersion ultrasonic inspection (Subtask 72-53-04-270-051) may be used in lieu of an FPI for the stage 2 disk dovetail serrations only. B. Clean, etch, and eddy current inspect (ECI) the HPTR stage two disk dovetail slot bottoms according to Chapter 72-53-04, High Pressure Turbine Rotor Stage 2 Disk- Inspection, paragraph 5, Special Inspection of Dovetail Slot Bottoms, of the reference shop manual. NOTE: If ECI capability is not available, the disk must be recleaned in accordance with paragraph 2.A (starting with Subtask 72-53-04-140-051). The slot bottoms must then be fluorescent penetrant inspected in accordance with paragraph 2.D (Subtask 72-53-04-230-001- 057) paying special attention to slot bottom corners. This amendment (39-7080, AD 91-15-16), becomes effective on September 4, 1991. FOOTER:
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