AD 55-23-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 1049C-55 | LOCKHEED Models 1049C, 1049D, 1049E, and 1049G |
| aircraft | Lockheed Aircraft Corporation | 1049D-55 | LOCKHEED Models 1049C, 1049D, 1049E, and 1049G |
| aircraft | Lockheed Aircraft Corporation | 1049E-55 | LOCKHEED Models 1049C, 1049D, 1049E, and 1049G |
| aircraft | Lockheed Aircraft Corporation | 1049G-82 | LOCKHEED Models 1049C, 1049D, 1049E, and 1049G |
Unsafe Condition
Cracks in the outer wing main beam web between wing Stations 510 and 668 left and right due to fatigue.
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Required Actions
Inspect the outer wing main beam web between Stations 510 and 668 for cracks as soon as practical and repeat at 125-hour intervals until reinforcement is done. Reinforce the web with three extruded 75S-T6 stiffeners (LS2186 or LS6097 or equivalent) between each original stiffener as soon as possible but no later than the next scheduled progressive overhaul or December 1, 1956, whichever comes first.
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Compliance Time
Compliance required as indicated. Reinforcement must be accomplished as soon as possible but not later than the next scheduled progressive overhaul time, and in no case later than December 1, 1956, whichever occurs first.
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Affected Aircraft
Lockheed Models 1049C, D, E, and G with serial numbers 4163-4166, 4520-4581, 4583-4605, 4608-4615, and 4620.
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Federal Register Abstract
Outer Wing Main Beam Web
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_55-23-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-23-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Models 1049C, 1049D, 1049E, and 1049G Subject: Outer Wing Main Beam Web Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Aircraft Corporation Model: 1049C-55 | 1049D-55 | 1049E-55 | 1049G-82 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 55-23-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-23-02 SUBJECT HEADING: LOCKHEED Models 1049C, 1049D, 1049E, and 1049G ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-23-02 LOCKHEED: Applies to Models 1049C, D, E, and G, Serial Numbers 4163 Through 4166, 4520 Through 4581, 4583 Through 4605, 4608 Through 4615, and 4620. Compliance required as indicated. 1. Inspect the outer wing main beam web between wing Stations 510 and 668 left and right for cracks as soon as practical and repeat at 125-hour intervals until reinforcement in accordance with paragraph 2 is accomplished. If cracks are found repair immediately in accordance with Lockheed Repair Manual, Report 8882, and continue 125-hour inspections until reinforcement per paragraph 2 is accomplished. Inspection for fuel stains alone as an indication of a crack is not sufficient because of the presence of fuel sealant on the forward side of the web. 2. To be accomplished as soon as possible, but not later than next scheduled progressive overhaul time, and in no case later than December 1, 1956, whichever occurs first: Reinforce the main beam web, left and right, between wing Stations 510 and 668. This shall be accomplished by the addition of three extruded 75S-T6 stiffeners, (LS2186 or LS6097) or equivalent between each of the original stiffeners. The LS347-3 stiffeners added previously in accordance with AD 54-24-02 on some of these aircraft may be retained. In these cases, one new (LS2186 or LS6097 or equivalent) stiffener must be added between each of these and the original stiffeners in this area. (Lockheed Service Bulletin No. 1049/SB-2753 also covers this subject.) FOOTER:
Document Text
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AD Final Rules - DRS_55-23-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-23-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Models 1049C, 1049D, 1049E, and 1049G Subject: Outer Wing Main Beam Web Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Aircraft Corporation Model: 1049C-55 | 1049D-55 | 1049E-55 | 1049G-82 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: 55-23-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-23-02 SUBJECT HEADING: LOCKHEED Models 1049C, 1049D, 1049E, and 1049G ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-23-02 LOCKHEED: Applies to Models 1049C, D, E, and G, Serial Numbers 4163 Through 4166, 4520 Through 4581, 4583 Through 4605, 4608 Through 4615, and 4620. Compliance required as indicated. 1. Inspect the outer wing main beam web between wing Stations 510 and 668 left and right for cracks as soon as practical and repeat at 125-hour intervals until reinforcement in accordance with paragraph 2 is accomplished. If cracks are found repair immediately in accordance with Lockheed Repair Manual, Report 8882, and continue 125-hour inspections until reinforcement per paragraph 2 is accomplished. Inspection for fuel stains alone as an indication of a crack is not sufficient because of the presence of fuel sealant on the forward side of the web. 2. To be accomplished as soon as possible, but not later than next scheduled progressive overhaul time, and in no case later than December 1, 1956, whichever occurs first: Reinforce the main beam web, left and right, between wing Stations 510 and 668. This shall be accomplished by the addition of three extruded 75S-T6 stiffeners, (LS2186 or LS6097) or equivalent between each of the original stiffeners. The LS347-3 stiffeners added previously in accordance with AD 54-24-02 on some of these aircraft may be retained. In these cases, one new (LS2186 or LS6097 or equivalent) stiffener must be added between each of these and the original stiffeners in this area. (Lockheed Service Bulletin No. 1049/SB-2753 also covers this subject.) FOOTER:
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Retrieved: Apr 8, 2026
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