AD 47-10-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 49-46 | LOCKHEED Model 49 |
Unsafe Condition
The soundproofing pads adjacent to and surrounding the voltage regulators may degrade, leading to potential electrical short circuits or overheating.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove all soundproofing pads adjacent to and surrounding the voltage regulators immediately.
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Compliance Time
Compliance required immediately.
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Affected Aircraft
Lockheed Aircraft Corporation Model 49 serial numbers up to and including 2088.
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Federal Register Abstract
Voltage Regulator Soundproofing
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-10-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Voltage Regulator Soundproofing 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Make: Lockheed Aircraft Corporation Model: 49-46 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-10-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-10 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-10 LOCKHEED: (Was Mandatory Note 12 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2088. Compliance required immediately. Remove all soundproofing pads adjacent to and surrounding the voltage regulators. (LAC Service Bulletin 49/SB-171 covers this same subject.) FOOTER:
Document Text
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AD Final Rules - DRS_47-10-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Voltage Regulator Soundproofing 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: 47-10-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-10 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-10 LOCKHEED: (Was Mandatory Note 12 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2088. Compliance required immediately. Remove all soundproofing pads adjacent to and surrounding the voltage regulators. (LAC Service Bulletin 49/SB-171 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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