AD 51-04-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Martin-Marietta Corporation | 202 | Martin Model 202 Aircraft |
Unsafe Condition
Failure of the carburetor vapor vent return line could cause fuel flow from the tank to the engine compartment, creating a fire hazard.
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Required Actions
Install a swing type check valve at each fuel tank where the vapor vent line attaches to the tank to prevent flow toward the engine compartment.
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Compliance Time
not later than April 1, 1951
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Affected Aircraft
All Martin Model 202 Aircraft
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Federal Register Abstract
Fuel Vent Line Check Valve
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_51-04-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-04-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Martin Model 202 Aircraft Subject: Fuel Vent Line Check Valve Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Martin-Marietta Corporation Model: 202 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 51-04-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-04-01 SUBJECT HEADING: Martin Model 202 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-04-01 MARTIN: Applies to All Model 202 Aircraft. Compliance required not later than April 1, 1951. In order to eliminate a fire hazard due to the possibility of flow from the tank to the engine compartment in case of the failure of the carburetor vapor vent return line, install a swing type check valve at each fuel tank where the vapor vent line attaches to the tank so that flow can take place only toward the fuel tank. (Martin Service Bulletin No. 138, dated November 30, 1950, covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_51-04-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-04-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Martin Model 202 Aircraft Subject: Fuel Vent Line Check Valve Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Martin-Marietta Corporation Model: 202 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: 51-04-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-04-01 SUBJECT HEADING: Martin Model 202 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-04-01 MARTIN: Applies to All Model 202 Aircraft. Compliance required not later than April 1, 1951. In order to eliminate a fire hazard due to the possibility of flow from the tank to the engine compartment in case of the failure of the carburetor vapor vent return line, install a swing type check valve at each fuel tank where the vapor vent line attaches to the tank so that flow can take place only toward the fuel tank. (Martin Service Bulletin No. 138, dated November 30, 1950, 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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