AD 47-10-23
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 49-46 | LOCKHEED Model 49 |
Unsafe Condition
Brass nuts (AC364-B524) installed on bolts through bathtub fittings at wing Station 80 may corrode and fail, leading to loss of wing structure integrity.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install AC364-524 steel nuts in place of any AC364-B524 brass nuts on bolts through bathtub fittings at wing Station 80. Check and replace all 170 nuts per airplane as necessary.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Compliance required immediately.
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Affected Aircraft
Lockheed Aircraft Corporation Model 49 serial numbers 1975, 1976, and 2021 through 2059.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Bathtub Fitting Steel Nuts
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-10-23.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-23 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Bathtub Fitting Steel Nuts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Aircraft Corporation Model: 49-46 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-10-23 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-23 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-23 LOCKHEED: (Was Mandatory Note 25 of AD-763-3.) Applies to Model 49 Serials 1975, 1976, and 2021 Through 2059. Compliance required immediately. Install AC364-524 steel nuts in place of any AC364-B524 brass nuts which may be installed on bolts through bathtub fittings at wing Station 80 (5 nuts per fitting, 170 nuts per airplane should be checked. (LAC Service Bulletin 49/SB-42 covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_47-10-23.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-23 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Bathtub Fitting Steel Nuts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Aircraft Corporation Model: 49-46 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: 47-10-23 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-23 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-23 LOCKHEED: (Was Mandatory Note 25 of AD-763-3.) Applies to Model 49 Serials 1975, 1976, and 2021 Through 2059. Compliance required immediately. Install AC364-524 steel nuts in place of any AC364-B524 brass nuts which may be installed on bolts through bathtub fittings at wing Station 80 (5 nuts per fitting, 170 nuts per airplane should be checked. (LAC Service Bulletin 49/SB-42 covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
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