AD 50-10-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sierra Hotel Aero, Inc. | Navion (Army L-17A) | Airworthiness Directives; All Navion Airplanes, Serial Numbers NAV-4-2 Through NAV-4-1790 |
| aircraft | Sierra Hotel Aero, Inc. | Navion A (Army L-17B and L-17C) | Airworthiness Directives; All Navion Airplanes, Serial Numbers NAV-4-2 Through NAV-4-1790 |
| aircraft | Sierra Hotel Aero, Inc. | Navion B | Airworthiness Directives; All Navion Airplanes, Serial Numbers NAV-4-2 Through NAV-4-1790 |
Unsafe Condition
The flexible hose (Ryan Drawing 145-42202) between the exhaust shroud and the carburetor heat valve may deteriorate with age and collapse, resulting in considerable loss of engine power.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the hose not later than March 20, 1950, and after each 25 hours of aircraft operation until replaced. Replace hoses in poor condition immediately with wire reinforced hose (Arrowhead Rubber Co. type 8AX or equivalent). Complete installation of the wire reinforced hose by September 1, 1950.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
by September 1, 1950
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Affected Aircraft
Sierra Hotel Aero, Inc. Navion (Army L-17A), Navion A (Army L-17B and L-17C), Navion B airplanes, serial numbers NAV-4-2 through NAV-4-1790
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Air Intake Hose
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_50-10-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 50-10-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; All Navion Airplanes, Serial Numbers NAV-4-2 Through NAV-4-1790 Subject: Air Intake Hose Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Sierra Hotel Aero, Inc. Model: Navion (Army L-17A) | Navion A (Army L-17B and L-17C) | Navion B Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 50-10-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 50-10-02 SUBJECT HEADING: Airworthiness Directives; All Navion Airplanes, Serial Numbers NAV-4-2 Through NAV-4-1790 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 50-10-02 NAVION: Applies to all Airplanes, Serial Numbers NAV-4-2 Through NAV-4- 1790. To be accomplished as indicated below. The above aircraft employ flexible hose, Ryan Drawing 145-42202, between the exhaust shroud and the carburetor heat valve. This hose has shown a tendency to deteriorate with age and may collapse, resulting in a considerable loss of engine power. An inspection of these hoses should be made not later than March 20, 1950, and after each 25 hours of aircraft operation until replacement is made with the hose mentioned below. All hoses found to be in poor condition should be replaced immediately by wire reinforced hose. Arrowhead Rubber Co. hose type 8AX (Ryan Drawing No. 145-42202-3) or equivalent is satisfactory. The installation of the above wire reinforced air intake hose in replacement of the original hose should be accomplished in all aircraft by September 1, 1950. (Ryan Service Letter No. 67 dated February 7, 1950, also covers this subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_50-10-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 50-10-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; All Navion Airplanes, Serial Numbers NAV-4-2 Through NAV-4-1790 Subject: Air Intake Hose Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Sierra Hotel Aero, Inc. Model: Navion (Army L-17A) | Navion A (Army L-17B and L-17C) | Navion B 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: 50-10-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 50-10-02 SUBJECT HEADING: Airworthiness Directives; All Navion Airplanes, Serial Numbers NAV-4-2 Through NAV-4-1790 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 50-10-02 NAVION: Applies to all Airplanes, Serial Numbers NAV-4-2 Through NAV-4- 1790. To be accomplished as indicated below. The above aircraft employ flexible hose, Ryan Drawing 145-42202, between the exhaust shroud and the carburetor heat valve. This hose has shown a tendency to deteriorate with age and may collapse, resulting in a considerable loss of engine power. An inspection of these hoses should be made not later than March 20, 1950, and after each 25 hours of aircraft operation until replacement is made with the hose mentioned below. All hoses found to be in poor condition should be replaced immediately by wire reinforced hose. Arrowhead Rubber Co. hose type 8AX (Ryan Drawing No. 145-42202-3) or equivalent is satisfactory. The installation of the above wire reinforced air intake hose in replacement of the original hose should be accomplished in all aircraft by September 1, 1950. (Ryan Service Letter No. 67 dated February 7, 1950, also covers this 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.
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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62-03-03
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47-31-03
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Unsafe Condition: Loss of fuel pressure due to air leakage into the fuel system through the CCA-1550-1/8 drain cock on the Koehler Model 2250 fuel strainer.
