AD 48-29-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sierra Hotel Aero, Inc. | Navion (Army L-17A) | Airworthiness Directives; All Navion Airplanes Employing Carter Engine Driven Fuel Pumps Not Presently Equipped With Vent Drain Lines |
Unsafe Condition
Rupture of the main diaphragm of Carter fuel pumps, which can cause fuel to squirt from the pump breather hole onto the engine, creating a fire hazard.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove the fiber screen and snap ring from the pump breather opening, install an overboard drain line to carry fuel clear of the airplane, and ensure the drain line vents into a low pressure area away from engine/cabin heater exhaust and air intake lines.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
as soon as possible but not later than October 15, 1948
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sierra Hotel Aero, Inc. Navion (Army L-17A) airplanes employing Carter engine driven fuel pumps not presently equipped with vent drain lines
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Fuel Pump Drain
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_48-29-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 48-29-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; All Navion Airplanes Employing Carter Engine Driven Fuel Pumps Not Present...Show more Subject: Fuel Pump Drain 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Sierra Hotel Aero, Inc. Model: Navion (Army L-17A) Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 48-29-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 48-29-01 SUBJECT HEADING: Airworthiness Directives; All Navion Airplanes Employing Carter Engine Driven Fuel Pumps Not Presently Equipped With Vent Drain Lines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 48-29-01 NAVION: Applies to All Airplanes Employing Carter Engine Driven Fuel Pumps Not Presently Equipped With Vent Drain Lines. To be accomplished as soon as possible but not later than October 15, 1948. Several instances of rupture of the main diaphragm of Carter fuel pumps have occurred. This is considered a fire hazard, since fuel can then squirt from the pump breather hole onto the engine. To correct this condition the pump breather should be provided with an overboard drain to carry fuel clear of the airplane if the diaphragm ruptures. Before installing the drain line, the fiber screen and snap ring must be removed from the pump breather opening. The drain line should vent into a low pressure area so that any fuel leaving this drain will not be in the proximity of any engine or cabin heater exhaust and will not contact the airplane or enter any air intake line, in ground or flight operation. (Ryan Navion Service Letter No. 47 covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_48-29-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 48-29-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; All Navion Airplanes Employing Carter Engine Driven Fuel Pumps Not Present...Show more Subject: Fuel Pump Drain 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: 48-29-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 48-29-01 SUBJECT HEADING: Airworthiness Directives; All Navion Airplanes Employing Carter Engine Driven Fuel Pumps Not Presently Equipped With Vent Drain Lines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 48-29-01 NAVION: Applies to All Airplanes Employing Carter Engine Driven Fuel Pumps Not Presently Equipped With Vent Drain Lines. To be accomplished as soon as possible but not later than October 15, 1948. Several instances of rupture of the main diaphragm of Carter fuel pumps have occurred. This is considered a fire hazard, since fuel can then squirt from the pump breather hole onto the engine. To correct this condition the pump breather should be provided with an overboard drain to carry fuel clear of the airplane if the diaphragm ruptures. Before installing the drain line, the fiber screen and snap ring must be removed from the pump breather opening. The drain line should vent into a low pressure area so that any fuel leaving this drain will not be in the proximity of any engine or cabin heater exhaust and will not contact the airplane or enter any air intake line, in ground or flight operation. (Ryan Navion Service Letter No. 47 covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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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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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.
