AD 47-10-20
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 49-46 | LOCKHEED Model 49 |
Unsafe Condition
The existing alcohol tanks and cradles are not sufficiently robust, posing a risk of failure.
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Required Actions
Replace existing alcohol tanks with new type heavier tanks, LAC P/N 296424. Replace existing tank cradles with new cradles LAC P/N 296465.
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Compliance Time
prior to June 1, 1947
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Affected Aircraft
Lockheed Aircraft Corporation Model 49 serials up to and including 2075
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Federal Register Abstract
Alcohol Tank Replacement
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-10-20.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-20 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Alcohol Tank Replacement 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Make: Lockheed Aircraft Corporation Model: 49-46 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-10-20 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-20 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-20 LOCKHEED: (Was Mandatory Note 22 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2075. Compliance required prior to June 1, 1947. Replace all existing alcohol tanks with new type heavier tanks, LAC P/N 296424. Replace existing tank cradles with new cradles LAC P/N 296465. (LAC Service Bulletin 49/SB-110, revised October 2, 1946, or subsequent, covers this same subject.) FOOTER:
Document Text
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AD Final Rules - DRS_47-10-20.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-20 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Alcohol Tank Replacement 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: 47-10-20 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-20 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-20 LOCKHEED: (Was Mandatory Note 22 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2075. Compliance required prior to June 1, 1947. Replace all existing alcohol tanks with new type heavier tanks, LAC P/N 296424. Replace existing tank cradles with new cradles LAC P/N 296465. (LAC Service Bulletin 49/SB-110, revised October 2, 1946, or subsequent, 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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