AD 53-15-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 149-46 | LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. |
| aircraft | Lockheed Aircraft Corporation | 49-46 | LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. |
| aircraft | Lockheed Aircraft Corporation | 649-79 | LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. |
| aircraft | Lockheed Aircraft Corporation | 649A-79 | LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. |
| aircraft | Lockheed Aircraft Corporation | 749-79 | LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. |
| aircraft | Lockheed Aircraft Corporation | 749A-79 | LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. |
Unsafe Condition
Cracks in the forward flange of the lower front spar cap at wing Station 326, left and right, particularly in spar cap joggle areas, which may extend into the vertical leg and compromise structural integrity.
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Required Actions
Inspect for cracks using dye penetrant inspection or equivalent. Stop drill cracks not extending into the vertical leg unless terminating in a rivet hole, repair permanently, or install serviceable repair per LAC Drawing 325800. If cracks extend into the vertical leg, remove tank sealant for skin and web inspection, then install reinforcement per LAC Drawing 325667, change A or equivalent. Reinforce before resuming commercial operation. Reinspect periodically as specified.
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Compliance Time
At the first arrival at the main base, unless already accomplished.
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Affected Aircraft
Lockheed Models 049, 149, 649, and 749 Series Aircraft.
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Federal Register Abstract
Wing Lower Front Spar Cap
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_53-15-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 53-15-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. Subject: Wing Lower Front Spar Cap Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Aircraft Corporation Model: 149-46 | 49-46 | 649-79 | 649A-79 | 749-79 | 749A-79 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: 53-15-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 53-15-02 SUBJECT HEADING: LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 53-15-02 LOCKHEED: Applies to All Models 049, 149, 649 and 749 Series Aircraft. Compliance required as indicated. At the first arrival at the main base, unless already accomplished, inspect for cracks in the forward flange of the lower front spar cap at wing Station 326, left and right, with particular reference to spar cap joggle areas using dye penetrant inspection method or equivalent. 1. If crack is found in the forward flange and does not extend into the vertical leg, stop drill the crack unless it terminates in a rivet hole and make permanent repair or install the serviceable repair in accordance with LAC Drawing 325800. When serviceable repair is used, a visual inspection must be conducted at periodic intervals not to exceed 50 hours with dye penetrant inspection or equivalent method to be used at periods not to exceed every 200 hours until incorporation of the reinforcement per LAC Drawing 325667, change A or equivalent. 2. If crack in the front spar flange extends into the vertical leg, remove tank sealant as necessary for skin and web inspection using dye penetrant inspection method or equivalent. Reinforcement per LAC Drawing 325667, change A or equivalent is necessary before resuming commercial operation and normal inspection procedures. 3. If no cracks are found, reinspect using dye penetrant inspection method or equivalent on all aircraft with 10,000 hours or more total flight time, at intervals not to exceed 200 hours, and on all other aircraft at each major airframe inspection period until such time as reinforcement per LAC Drawing 325667, change A or equivalent is accomplished. FOOTER:
Document Text
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AD Final Rules - DRS_53-15-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 53-15-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. Subject: Wing Lower Front Spar Cap Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Aircraft Corporation Model: 149-46 | 49-46 | 649-79 | 649A-79 | 749-79 | 749A-79 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: 53-15-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 53-15-02 SUBJECT HEADING: LOCKHEED Models 049, 149, 649 and 749 Series Aircraft. ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 53-15-02 LOCKHEED: Applies to All Models 049, 149, 649 and 749 Series Aircraft. Compliance required as indicated. At the first arrival at the main base, unless already accomplished, inspect for cracks in the forward flange of the lower front spar cap at wing Station 326, left and right, with particular reference to spar cap joggle areas using dye penetrant inspection method or equivalent. 1. If crack is found in the forward flange and does not extend into the vertical leg, stop drill the crack unless it terminates in a rivet hole and make permanent repair or install the serviceable repair in accordance with LAC Drawing 325800. When serviceable repair is used, a visual inspection must be conducted at periodic intervals not to exceed 50 hours with dye penetrant inspection or equivalent method to be used at periods not to exceed every 200 hours until incorporation of the reinforcement per LAC Drawing 325667, change A or equivalent. 2. If crack in the front spar flange extends into the vertical leg, remove tank sealant as necessary for skin and web inspection using dye penetrant inspection method or equivalent. Reinforcement per LAC Drawing 325667, change A or equivalent is necessary before resuming commercial operation and normal inspection procedures. 3. If no cracks are found, reinspect using dye penetrant inspection method or equivalent on all aircraft with 10,000 hours or more total flight time, at intervals not to exceed 200 hours, and on all other aircraft at each major airframe inspection period until such time as reinforcement per LAC Drawing 325667, change A or equivalent is accomplished. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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