AD 49-05-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sierra Hotel Aero, Inc. | Navion (Army L-17A) | Airworthiness Directives; Navion Airplanes Equipped With Continental Model E185-3 Engines Having Serial Numbers 4289-D to 5110-D Inclusive, and Engines Which Have Been Equipped at Overhaul With Tri-Metal Front Main Bearing Inserts and Bronze Thrust Washers in Accordance With Continental Bulletin No. M48-7. |
| aircraft | Sierra Hotel Aero, Inc. | Navion A (Army L-17B and L-17C) | Airworthiness Directives; Navion Airplanes Equipped With Continental Model E185-3 Engines Having Serial Numbers 4289-D to 5110-D Inclusive, and Engines Which Have Been Equipped at Overhaul With Tri-Metal Front Main Bearing Inserts and Bronze Thrust Washers in Accordance With Continental Bulletin No. M48-7. |
Unsafe Condition
Unsatisfactory service experience with Continental E185-3 engines equipped with No. 530497 Tri-Metal front main bearing inserts and thrust washers/pins (Nos. 530494, 530495, 530544 and 530545 dowel pins) leading to potential engine failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace No. 530497 Tri-Metal front main bearing inserts and Nos. 530494, 530495, 530544 thrust washers and 530545 dowel pins with original silver main thrust bearing inserts (Continental No. 40644).
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 the first major engine overhaul
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Navion (Army L-17A) and Navion A (Army L-17B and L-17C) airplanes equipped with Continental Model E185-3 engines having serial numbers 4289-D to 5110-D inclusive, or engines overhauled with tri-metal front main bearing inserts and bronze thrust washers per Continental Bulletin No. M48-7
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Continental Engines Bearing Inserts
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_49-05-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-05-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Navion Airplanes Equipped With Continental Model E185-3 Engines Having Ser...Show more Subject: Continental Engines Bearing Inserts 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: 49-05-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-05-03 SUBJECT HEADING: Airworthiness Directives; Navion Airplanes Equipped With Continental Model E185-3 Engines Having Serial Numbers 4289-D to 5110-D Inclusive, and Engines Which Have Been Equipped at Overhaul With Tri-Metal Front Main Bearing Inserts and Bronze Thrust Washers in Accordance With Continental Bulletin No. M48-7. ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-05-03 NAVION: Applies to Airplanes Equipped With Continental Model E185-3 Engines Having Serial Numbers 4289-D to 5110-D Inclusive, and Engines Which Have Been Equipped at Overhaul With Tri-Metal Front Main Bearing Inserts and Bronze Thrust Washers in Accordance With Continental Bulletin No. M48-7. To be accomplished as soon as possible but not later than the first major engine overhaul. Because of unsatisfactory service experience with Continental E185-3 engines equipped with No. 530497 Tri-Metal front main bearing inserts, and with Nos. 530494, 530495, 530544 thrust washers and 530545 dowel pins, these parts must be replaced with the original silver main thrust bearing inserts, Continental No. 40644. Continental Service Bulletin M48-30 covers this same subject. (Ryan Navion Field Service Bulletin No. 5 outlines the interim precautions to be taken on airplanes equipped with the unsatisfactory thrust washers until silver main thrust bearings are installed in accordance with this note.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_49-05-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-05-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Navion Airplanes Equipped With Continental Model E185-3 Engines Having Ser...Show more Subject: Continental Engines Bearing Inserts 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: 49-05-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-05-03 SUBJECT HEADING: Airworthiness Directives; Navion Airplanes Equipped With Continental Model E185-3 Engines Having Serial Numbers 4289-D to 5110-D Inclusive, and Engines Which Have Been Equipped at Overhaul With Tri-Metal Front Main Bearing Inserts and Bronze Thrust Washers in Accordance With Continental Bulletin No. M48-7. ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-05-03 NAVION: Applies to Airplanes Equipped With Continental Model E185-3 Engines Having Serial Numbers 4289-D to 5110-D Inclusive, and Engines Which Have Been Equipped at Overhaul With Tri-Metal Front Main Bearing Inserts and Bronze Thrust Washers in Accordance With Continental Bulletin No. M48-7. To be accomplished as soon as possible but not later than the first major engine overhaul. Because of unsatisfactory service experience with Continental E185-3 engines equipped with No. 530497 Tri-Metal front main bearing inserts, and with Nos. 530494, 530495, 530544 thrust washers and 530545 dowel pins, these parts must be replaced with the original silver main thrust bearing inserts, Continental No. 40644. Continental Service Bulletin M48-30 covers this same subject. (Ryan Navion Field Service Bulletin No. 5 outlines the interim precautions to be taken on airplanes equipped with the unsatisfactory thrust washers until silver main thrust bearings are installed in accordance with this note.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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