AD 47-31-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sierra Hotel Aero, Inc. | Navion (Army L-17A) | Airworthiness Directives; Navion Serial Numbers NAV-4-2 Through NAV-4-850 |
Unsafe Condition
Premature failure of the carburetor vapor return line hose P/N 75696 in the event of an engine compartment fire.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove carburetor vapor return line hose P/N 75696 and install fire-resistant hose P/N 76701.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
not later than November 1, 1947
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Affected Aircraft
Sierra Hotel Aero, Inc. Navion (Army L-17A) serial numbers NAV-4-2 through NAV-4-850
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Carburetor Vapor Return Line
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-31-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-31-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Navion Serial Numbers NAV-4-2 Through NAV-4-850 Subject: Carburetor Vapor Return Line Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Sierra Hotel Aero, Inc. Model: Navion (Army L-17A) Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-31-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-31-02 SUBJECT HEADING: Airworthiness Directives; Navion Serial Numbers NAV-4-2 Through NAV-4-850 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-31-02 NAVION: (Was Mandatory Note 11 of AD-782-3.) Applies to Serial Numbers NAV-4-2 Through NAV-4-850. To be accomplished not later than November 1, 1947. Remove carburetor vapor return line hose P/N 75696 and install fire-resistant hose P/N 76701. This change is necessary to prevent premature failure of the vapor return line in the event of an engine compartment fire. (NAA Field Service Bulletin No. 23 dated April 11, 1947, covers this rework.) FOOTER:
Document Text
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AD Final Rules - DRS_47-31-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-31-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Navion Serial Numbers NAV-4-2 Through NAV-4-850 Subject: Carburetor Vapor Return Line Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Sierra Hotel Aero, Inc. Model: Navion (Army L-17A) Product Type: Aircraft Product Subtype: Small 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: 47-31-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-31-02 SUBJECT HEADING: Airworthiness Directives; Navion Serial Numbers NAV-4-2 Through NAV-4-850 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-31-02 NAVION: (Was Mandatory Note 11 of AD-782-3.) Applies to Serial Numbers NAV-4-2 Through NAV-4-850. To be accomplished not later than November 1, 1947. Remove carburetor vapor return line hose P/N 75696 and install fire-resistant hose P/N 76701. This change is necessary to prevent premature failure of the vapor return line in the event of an engine compartment fire. (NAA Field Service Bulletin No. 23 dated April 11, 1947, covers this rework.) 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.
Related Airworthiness Directives
2008-05-14 Recurring
final ruleAirworthiness Directives; Sierra Hotel Aero, Inc. Models Navion (L-17A), Navion A (L-17B), (L-17C), Navion B, Navion D, Navion E, Navion F, Navion G, and Navion H Airplanes
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