AD 84-26-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | DC-9-11 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-12 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-13 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-14 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-15 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-15F | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-21 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-31 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-32 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-32 (VC-9C) | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-32F | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-32F (C-9A) | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-32F (C-9B) | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-33F | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-34 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-34F | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-41 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
| aircraft | The Boeing Company | DC-9-51 | Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes |
Unsafe Condition
Cracks in the MLG attach fitting and its interrelated structure could lead to failure of the fitting.
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Required Actions
Inspect MLG attach fittings for cracks within specified landing intervals (3,600 or 1,800 additional landings) based on landing count. Repetitive inspections must be performed at 3,600 landing intervals until replaced or modified. If cracks are found, rework or replace the fitting before further flight. Preventative modification per SB 57-148, R1, or replacement constitutes terminating action.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Compliance is required as indicated, unless previously accomplished.
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Affected Aircraft
McDonnell Douglas Model DC-9-10, -20, -30, -40, -50, C-9 (Military) series airplanes with MLG attach fittings from forging alloy 7075-T73 and which have accomplished Option I of Service Bulletin 57-125, Revision 2 or prior issues.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
MLG Attach Fittings
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_84-26-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 84-26-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes Subject: MLG Attach Fittings Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/27/1985 Make: The Boeing Company Model: DC-9-11 | DC-9-12 | DC-9-13 | DC-9-14 | DC-9-15 | DC-9-15F | DC-9-21 | DC-9-31 | DC-9-32 | DC-9-32 (...Show more Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 84-26-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4971 AD NUMBER: 84-26-01 SUBJECT HEADING: Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes ACTION: SUMMARY: DATES: Effective January 27, 1985. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 84-26-01 McDONNELL DOUGLAS: Amendment 39-4971. Applies to McDonnell Douglas Model DC-9-10, -20, -30, -40, -50, C-9 (Military) series airplanes, certificated in all categories, which have accomplished Option I of McDonnell Douglas DC-9 Service Bulletin 57-125, Revision 2, or prior issues and have installed MLG attach fitting fabricated from forging alloy 7075-T73. Specific corresponding factory serial numbers for the production effectivity are listed in McDonnell Douglas DC-9 Service Bulletin 57-148, Revision 1, dated June 8, 1983, hereinafter referred to as SB 57-148, R1. Compliance is required as indicated, unless previously accomplished. To detect cracks and prevent failure of the MLG attach fitting and its interrelated structure, accomplish the following: A. For aircraft with fittings having 15,000 to 19,999 landings, inspect the affected MLG attach fittings for cracks within 3,600 additional landings in accordance with SB 57-148, R1. B. For aircraft with fittings having 20,000 or more landings, inspect the affected MLG attach fittings for cracks within 1,800 additional landings, in accordance with SB 57-148, R1. C. Repetitive inspections must be performed at 3,600 landings intervals until replaced with a new fitting or preventative modification is accomplished in accordance with SB 57-148, R1. D. If an MLG attach fitting is found cracked, the affected MLG attach fitting(s) must be reworked in accordance with SB 57-148, R1, or later FAA approved revisions, prior to further flight. E. If cracks are found in locations in the fitting(s) other than those identified in SB 57-148, R1, replace the fitting(s) before further flight in accordance with SB 57-125, R4, Option 1, or rework in a manner approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region. F. If preventative modification is not accomplished prior to 37,000 landings, continue repetitive inspections at 3,600 landing intervals, until such time terminating action is accomplished. G. Completion of the preventative modification in accordance with SB 57-148, R1, or the replacement of cracked fitting(s) in accordance with SB 57-125, R4, or later FAA approved revisions, constitutes terminating action for this AD. H. Alternative inspections, modifications, or other actions which provide an equivalent level of safety may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region. I. Upon request of operator, an FAA Maintenance Inspector, subject to prior approval of the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Director, Publications and Training, C1-750 (54-60). These documents also may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Los Angeles Aircraft Certification Office, 4344 Donald Douglas Drive, Long Beach, California. This amendment becomes effective January 27, 1985. FOOTER:
Document Text
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AD Final Rules - DRS_84-26-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 84-26-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes Subject: MLG Attach Fittings Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/27/1985 Make: The Boeing Company Model: DC-9-11 | DC-9-12 | DC-9-13 | DC-9-14 | DC-9-15 | DC-9-15F | DC-9-21 | DC-9-31 | DC-9-32 | DC-9-32 (...Show more Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 84-26-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4971 AD NUMBER: 84-26-01 SUBJECT HEADING: Airworthiness Directives; McDONNELL DOUGLAS DC-9-10, -20, -30, -40, -50, C-9 (Military) Series Airplanes ACTION: SUMMARY: DATES: Effective January 27, 1985. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 84-26-01 McDONNELL DOUGLAS: Amendment 39-4971. Applies to McDonnell Douglas Model DC-9-10, -20, -30, -40, -50, C-9 (Military) series airplanes, certificated in all categories, which have accomplished Option I of McDonnell Douglas DC-9 Service Bulletin 57-125, Revision 2, or prior issues and have installed MLG attach fitting fabricated from forging alloy 7075-T73. Specific corresponding factory serial numbers for the production effectivity are listed in McDonnell Douglas DC-9 Service Bulletin 57-148, Revision 1, dated June 8, 1983, hereinafter referred to as SB 57-148, R1. Compliance is required as indicated, unless previously accomplished. To detect cracks and prevent failure of the MLG attach fitting and its interrelated structure, accomplish the following: A. For aircraft with fittings having 15,000 to 19,999 landings, inspect the affected MLG attach fittings for cracks within 3,600 additional landings in accordance with SB 57-148, R1. B. For aircraft with fittings having 20,000 or more landings, inspect the affected MLG attach fittings for cracks within 1,800 additional landings, in accordance with SB 57-148, R1. C. Repetitive inspections must be performed at 3,600 landings intervals until replaced with a new fitting or preventative modification is accomplished in accordance with SB 57-148, R1. D. If an MLG attach fitting is found cracked, the affected MLG attach fitting(s) must be reworked in accordance with SB 57-148, R1, or later FAA approved revisions, prior to further flight. E. If cracks are found in locations in the fitting(s) other than those identified in SB 57-148, R1, replace the fitting(s) before further flight in accordance with SB 57-125, R4, Option 1, or rework in a manner approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region. F. If preventative modification is not accomplished prior to 37,000 landings, continue repetitive inspections at 3,600 landing intervals, until such time terminating action is accomplished. G. Completion of the preventative modification in accordance with SB 57-148, R1, or the replacement of cracked fitting(s) in accordance with SB 57-125, R4, or later FAA approved revisions, constitutes terminating action for this AD. H. Alternative inspections, modifications, or other actions which provide an equivalent level of safety may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region. I. Upon request of operator, an FAA Maintenance Inspector, subject to prior approval of the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Director, Publications and Training, C1-750 (54-60). These documents also may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Los Angeles Aircraft Certification Office, 4344 Donald Douglas Drive, Long Beach, California. This amendment becomes effective January 27, 1985. FOOTER:
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Retrieved: Apr 8, 2026
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