AD 55-22-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Textron Aviation Inc. | 35 | Airworthiness Directives; Beech Model 35 Airplanes |
| aircraft | Textron Aviation Inc. | 35-33 | Airworthiness Directives; Beech Model 35 Airplanes |
| aircraft | Textron Aviation Inc. | 35-A33 | Airworthiness Directives; Beech Model 35 Airplanes |
| aircraft | Textron Aviation Inc. | 35-B33 | Airworthiness Directives; Beech Model 35 Airplanes |
| aircraft | Textron Aviation Inc. | 35-C33 | Airworthiness Directives; Beech Model 35 Airplanes |
| aircraft | Textron Aviation Inc. | 35-C33A | Airworthiness Directives; Beech Model 35 Airplanes |
| aircraft | Textron Aviation Inc. | 35R | Airworthiness Directives; Beech Model 35 Airplanes |
Unsafe Condition
Failure of oil supply line hose connects caused by engine counter rotation, leading to complete loss of the engine oil supply.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Modify the oil tank outlet check valve by drilling 1/16-inch holes in the poppet face or remove the valve's internal parts (poppet pivot pin, spring, and poppet).
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 January 1, 1956
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Beech Model 35 Airplanes, serial numbers D-1 through D-550, equipped with unmodified oil tank check valves.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Oil Outlet Check Valve
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_55-22-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-22-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Beech Model 35 Airplanes Subject: Oil Outlet Check Valve Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Textron Aviation Inc. Model: 35 | 35-33 | 35-A33 | 35-B33 | 35-C33 | 35-C33A | 35R Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 55-22-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-22-01 SUBJECT HEADING: Airworthiness Directives; Beech Model 35 Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-22-01 BEECH: Applies to All Model 35 Airplanes, Serial Numbers D-1 Through D- 550, Equipped With Unmodified Oil Tank Check Valves. Compliance required as soon as possible but not later than January 1, 1956. To prevent complete loss of the engine oil supply resulting from failure of oil supply line hose connects caused by engine counter rotation, the check valve located at oil tank outlet requires valve modification or removal of the valve internal parts. Modified valves supplied by Beech Aircraft (Beech P/N 35-939082) include 1/16-inch holes drilled in the face of the valve poppet to prevent pressure buildup in the oil supply line in case of engine counter rotation. Modified valves are not available from Beech Aircraft. Unmodified valves should have the internal parts (poppet pivot pin, spring and poppet) removed. (Beech Service Bulletin Model 35, No. 30, issued July 15, 1955; Service Letter Model 35, No. 44, issued March 28, 1950, and Service Letter Model 35, No. 18, issued July 18, 1947, cover this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_55-22-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-22-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Beech Model 35 Airplanes Subject: Oil Outlet Check Valve Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Textron Aviation Inc. Model: 35 | 35-33 | 35-A33 | 35-B33 | 35-C33 | 35-C33A | 35R 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: 55-22-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-22-01 SUBJECT HEADING: Airworthiness Directives; Beech Model 35 Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-22-01 BEECH: Applies to All Model 35 Airplanes, Serial Numbers D-1 Through D- 550, Equipped With Unmodified Oil Tank Check Valves. Compliance required as soon as possible but not later than January 1, 1956. To prevent complete loss of the engine oil supply resulting from failure of oil supply line hose connects caused by engine counter rotation, the check valve located at oil tank outlet requires valve modification or removal of the valve internal parts. Modified valves supplied by Beech Aircraft (Beech P/N 35-939082) include 1/16-inch holes drilled in the face of the valve poppet to prevent pressure buildup in the oil supply line in case of engine counter rotation. Modified valves are not available from Beech Aircraft. Unmodified valves should have the internal parts (poppet pivot pin, spring and poppet) removed. (Beech Service Bulletin Model 35, No. 30, issued July 15, 1955; Service Letter Model 35, No. 44, issued March 28, 1950, and Service Letter Model 35, No. 18, issued July 18, 1947, cover this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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