AD 49-11-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sierra Hotel Aero, Inc. | Navion (Army L-17A) | Airworthiness Directives; Navion Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (Carter M687-S and M688-S) or Continental P/N 50375 |
| aircraft | Sierra Hotel Aero, Inc. | Navion A (Army L-17B and L-17C) | Airworthiness Directives; Navion Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (Carter M687-S and M688-S) or Continental P/N 50375 |
Unsafe Condition
Carter fuel pump lower diaphragm failures caused by diaphragm deterioration due to excessive pump temperatures when pumps are run dry.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Convert parallel Carter pump fuel systems to series pump arrangement or install an approved Ryan fuel system with Adel electric booster pump or equivalent approved fuel system. Continue daily inspections for looseness of the pump lower bowl as specified in Ryan's Bulletin No. 7.
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 April 15, 1949
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Affected Aircraft
Sierra Hotel Aero, Inc. Navion (Army L-17A) and Navion A (Army L-17B and L-17C) models equipped with Carter Fuel Pumps Continental P/N 530509 (Carter M687-S and M688-S) or Continental P/N 50375.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Carter Fuel Pump Rework
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_49-11-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-11-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Navion Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (C...Show more Subject: Carter Fuel Pump Rework 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(Army L-17A) | Navion A (Army L-17B and L-17C) Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 49-11-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-11-01 SUBJECT HEADING: Airworthiness Directives; Navion Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (Carter M687-S and M688-S) or Continental P/N 50375 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-11-01 NAVION: Applies to Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (Carter M687-S and M688-S) or Continental P/N 50375. To be accomplished as soon as possible but not later than April 15, 1949. Due to Carter fuel pump lower diaphragm failures, caused by diaphragm deterioration due to excessive pump temperatures when pumps are run dry, the two Carter pumps should be connected in series to insure that fuel will be continuously flowing both pumps and that the pumps will not overheat. It is therefore required that all parallel Carter pump fuel systems be converted to the series pump arrangement, or, as an alternative, that either an approved Ryan fuel system incorporating an Adel electric booster pump or an equivalent approved fuel system be installed. Ryan Navion Field Service Bulletin No. 7 also covers this subject and describes means for connecting the fuel pumps in series. In addition, the daily inspections for looseness of the pump lower bowl, which are specified in section II of Ryan's Bulletin No. 7, should be continued. This supersedes AD 48-40-01. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_49-11-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-11-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Navion Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (C...Show more Subject: Carter Fuel Pump Rework 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) 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: 49-11-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-11-01 SUBJECT HEADING: Airworthiness Directives; Navion Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (Carter M687-S and M688-S) or Continental P/N 50375 ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-11-01 NAVION: Applies to Airplanes Equipped With Carter Fuel Pumps Continental P/N 530509 (Carter M687-S and M688-S) or Continental P/N 50375. To be accomplished as soon as possible but not later than April 15, 1949. Due to Carter fuel pump lower diaphragm failures, caused by diaphragm deterioration due to excessive pump temperatures when pumps are run dry, the two Carter pumps should be connected in series to insure that fuel will be continuously flowing both pumps and that the pumps will not overheat. It is therefore required that all parallel Carter pump fuel systems be converted to the series pump arrangement, or, as an alternative, that either an approved Ryan fuel system incorporating an Adel electric booster pump or an equivalent approved fuel system be installed. Ryan Navion Field Service Bulletin No. 7 also covers this subject and describes means for connecting the fuel pumps in series. In addition, the daily inspections for looseness of the pump lower bowl, which are specified in section II of Ryan's Bulletin No. 7, should be continued. This supersedes AD 48-40-01. 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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