AD 51-07-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sierra Hotel Aero, Inc. | Navion (Army L-17A) | Airworthiness Directives; All Navion Models Having Serial Numbers 1789 through 2019; 2021 through 2026; 2028 through 2142; 2144 through 2169; 2171 through 2177; and 2180 |
| aircraft | Sierra Hotel Aero, Inc. | Navion A (Army L-17B and L-17C) | Airworthiness Directives; All Navion Models Having Serial Numbers 1789 through 2019; 2021 through 2026; 2028 through 2142; 2144 through 2169; 2171 through 2177; and 2180 |
| aircraft | Sierra Hotel Aero, Inc. | Navion B | Airworthiness Directives; All Navion Models Having Serial Numbers 1789 through 2019; 2021 through 2026; 2028 through 2142; 2144 through 2169; 2171 through 2177; and 2180 |
Unsafe Condition
Throttle housing slippage at the swaged joint between the cable housing and ferrule at the instrument panel end can result in erratic throttle operation.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect controls for housing slippage by March 5, 1951, and replace any affected controls immediately. Install a special stop nut on the throttle shaft by July 15, 1951, to prevent inner shaft contact with the housing end.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
not later than March 5, 1951 for inspection and replacement; special stop nut must be installed by July 15, 1951
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sierra Hotel Aero, Inc. Navion models with serial numbers 1789 through 2019; 2021 through 2026; 2028 through 2142; 2144 through 2169; 2171 through 2177; and 2180
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Throttle Housing
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_51-07-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-07-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; All Navion Models Having Serial Numbers 1789 through 2019; 2021 through 20...Show more Subject: Throttle Housing 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: 51-07-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-07-01 SUBJECT HEADING: Airworthiness Directives; All Navion Models Having Serial Numbers 1789 through 2019; 2021 through 2026; 2028 through 2142; 2144 through 2169; 2171 through 2177; and 2180 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-07-01 NAVION: Applies to All Models Having Serial Numbers 1789 Through 2019; 2021 Through 2026; 2028 Through 2142; 2144 Through 2169; 2171 Through 2177; and 2180. To be accomplished as indicated below. It has been found that on some of these airplanes throttle housing slippage has occurred at the point where the cable housing is swaged to the ferrule at the instrument panel end. This slippage can result in erratic throttle operation. An inspection of these controls for evidence of housing slippage must be made not later than March 5, 1951. Any control showing evidence of slippage shall be replaced immediately. It has been found that housing slippage may be caused by the inner shaft in the control head striking the end of the housing when the throttle is moved to the full open position. To prevent such occurrence, a special stop nut must be installed on the throttle shaft in place of the existing jam nut. This special nut, which will prevent the inner shaft from striking the end of the housing, is being furnished by the Ryan Co. and must be installed by July 15, 1951. (Ryan Field Service Bulletin No. 9, dated September 1, 1950, covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_51-07-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-07-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; All Navion Models Having Serial Numbers 1789 through 2019; 2021 through 20...Show more Subject: Throttle Housing 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: 51-07-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-07-01 SUBJECT HEADING: Airworthiness Directives; All Navion Models Having Serial Numbers 1789 through 2019; 2021 through 2026; 2028 through 2142; 2144 through 2169; 2171 through 2177; and 2180 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-07-01 NAVION: Applies to All Models Having Serial Numbers 1789 Through 2019; 2021 Through 2026; 2028 Through 2142; 2144 Through 2169; 2171 Through 2177; and 2180. To be accomplished as indicated below. It has been found that on some of these airplanes throttle housing slippage has occurred at the point where the cable housing is swaged to the ferrule at the instrument panel end. This slippage can result in erratic throttle operation. An inspection of these controls for evidence of housing slippage must be made not later than March 5, 1951. Any control showing evidence of slippage shall be replaced immediately. It has been found that housing slippage may be caused by the inner shaft in the control head striking the end of the housing when the throttle is moved to the full open position. To prevent such occurrence, a special stop nut must be installed on the throttle shaft in place of the existing jam nut. This special nut, which will prevent the inner shaft from striking the end of the housing, is being furnished by the Ryan Co. and must be installed by July 15, 1951. (Ryan Field Service Bulletin No. 9, dated September 1, 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.
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
Unsafe Condition: Leaking or improperly operating fuel selector valves may disrupt fuel flow to the engine, leading to engine power loss.
68-20-06
final ruleAirworthiness Directives; Navion Models Navion through Navion H Airplanes
Unsafe Condition: Failure of the Rudder Horn, P/N 145-24401, due to horizontal cracks or corrosion in the edge, which may appear as delaminations or swelling under the paint.
62-03-03
final ruleAirworthiness Directives; Navion Models Navion, Navion A, Navion B, Navion D, Navion E, Navion F, and Navion G Aircraft
Unsafe Condition: The landing gear selector valve end fitting P/N 145-58145-3 (heat treated and non-heat treated) has a service history of failure during attempts to extend the gear.
47-31-03
final ruleAirworthiness Directives; Navion Serial Numbers NAV-4-2 Through NAV-4-1010 Which Incorporate Koehler Model 2250 Fuel Strainers
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.
