AD 47-10-26
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 49-46 | LOCKHEED Model 49 |
Unsafe Condition
Flap drain line routing through the aspirator could cause hydraulic fluid leakage and system malfunction.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Reroute flap and fan motor drain lines to return directly to the main hydraulic system and install check valves at the connection points.
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Compliance Time
prior to June 1, 1947
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Affected Aircraft
Lockheed Aircraft Corporation Model 49-46, serial numbers up to and including 2075.
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Federal Register Abstract
Flap drain Line Rerouting
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-10-26.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-26 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Flap drain Line Rerouting 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Make: Lockheed Aircraft Corporation Model: 49-46 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-10-26 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-26 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-26 LOCKHEED: (Was Mandatory Note 29 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2075. Compliance required prior to June 1, 1947. Reroute flap and fan motor drain lines to return direct to main hydraulic system instead of through aspirator, and install check valves at points where drain lines connect to the main system. (LAC Service Bulletin 49/SB-169 covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_47-10-26.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-10-26 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 49 Subject: Flap drain Line Rerouting 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: 47-10-26 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-10-26 SUBJECT HEADING: LOCKHEED Model 49 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-10-26 LOCKHEED: (Was Mandatory Note 29 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2075. Compliance required prior to June 1, 1947. Reroute flap and fan motor drain lines to return direct to main hydraulic system instead of through aspirator, and install check valves at points where drain lines connect to the main system. (LAC Service Bulletin 49/SB-169 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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