AD 78-12-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Pratt & Whitney Canada Corp. | PT6A-38 | PRATT & WHITNEY AIRCRAFT (Canada) Model PT6A-38, PT6A-41, PT6A-45A Engines |
| engine | Pratt & Whitney Canada Corp. | PT6A-41 | PRATT & WHITNEY AIRCRAFT (Canada) Model PT6A-38, PT6A-41, PT6A-45A Engines |
| engine | Pratt & Whitney Canada Corp. | PT6A-45A | PRATT & WHITNEY AIRCRAFT (Canada) Model PT6A-38, PT6A-41, PT6A-45A Engines |
Unsafe Condition
Oil leakage from the No. 2 bearing pressure oil transfer tube assembly due to the use of Part Number 3019268 or 3027054 tube assemblies.
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Required Actions
Replace Part Number 3019268 and 3027054 No. 2 bearing pressure oil transfer tube assemblies with Part Number 3030150 tube assembly following Pratt & Whitney Service Bulletin No. 3099 or approved equivalent parts.
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Compliance Time
within the next 50 hours in service after the effective date of this AD
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Affected Aircraft
Pratt & Whitney Aircraft of Canada, Limited PT6A-38 engines prior to Serial Number PCE-79179, PT6A-41 engines prior to Serial Number PCE-80718, PT6A-45A engines prior to Serial Number PCE-84108, and PT6A-38 engines prior to Serial Number P-79179 with Part Number 3019268 or 3027054 No. 2 bearing pressure oil transfer tube assemblies.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
No. 2 Bearing Pressure Oil Transfer Tube Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_78-12-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-12-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY AIRCRAFT (Canada) Model PT6A-38, PT6A-41, PT6A-45A Engines Subject: No. 2 Bearing Pressure Oil Transfer Tube Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/19/1978 Make: Pratt & Whitney Canada Corp. Model: PT6A-38 | PT6A-41 | PT6A-45A Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 78-12-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3234 AD NUMBER: 78-12-04 SUBJECT HEADING: PRATT & WHITNEY AIRCRAFT (Canada) Model PT6A-38, PT6A-41, PT6A-45A Engines ACTION: SUMMARY: DATES: Effective June 19, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-12-04 PRATT & WHITNEY AIRCRAFT: Amendment 39-3234. Applies to all Pratt & Whitney Aircraft of Canada, Limited PT6A-38 engines prior to Serial Number PCE-79179, PT6A-41 engines prior to Serial Number PCE-80718, PT6A-45A engines prior to Serial Number PCE-84108 and Pratt & Whitney Aircraft PT6A-38 engines prior to Serial Number P-79179 with Part Number 3019268 or 3027054 No. 2 bearing pressure oil transfer tube assemblies. Compliance required within the next 50 hours in service, after the effective date of this AD, unless already accomplished. To preclude oil leakage from the No. 2 bearing pressure oil transfer tube assembly replace the Part Number 3019268 and 3027054 tube assemblies with Part Number 3030150 tube assembly in accordance with Paragraph 2, accomplishment instructions in Pratt & Whitney Aircraft of Canada, Limited Service Bulletin No. 3099 or approved equivalent parts. Aircraft may be flown to a base for performance of maintenance required by this AD per FAR 21.197 or FAR 21.199. All equivalent parts must be approved by the Chief, Engineering and Manufacturing Branch of the Eastern Region of the FAA. This amendment is effective June 19, 1978. FOOTER:
Document Text
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AD Final Rules - DRS_78-12-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-12-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY AIRCRAFT (Canada) Model PT6A-38, PT6A-41, PT6A-45A Engines Subject: No. 2 Bearing Pressure Oil Transfer Tube Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/19/1978 Make: Pratt & Whitney Canada Corp. Model: PT6A-38 | PT6A-41 | PT6A-45A Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 78-12-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3234 AD NUMBER: 78-12-04 SUBJECT HEADING: PRATT & WHITNEY AIRCRAFT (Canada) Model PT6A-38, PT6A-41, PT6A-45A Engines ACTION: SUMMARY: DATES: Effective June 19, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-12-04 PRATT & WHITNEY AIRCRAFT: Amendment 39-3234. Applies to all Pratt & Whitney Aircraft of Canada, Limited PT6A-38 engines prior to Serial Number PCE-79179, PT6A-41 engines prior to Serial Number PCE-80718, PT6A-45A engines prior to Serial Number PCE-84108 and Pratt & Whitney Aircraft PT6A-38 engines prior to Serial Number P-79179 with Part Number 3019268 or 3027054 No. 2 bearing pressure oil transfer tube assemblies. Compliance required within the next 50 hours in service, after the effective date of this AD, unless already accomplished. To preclude oil leakage from the No. 2 bearing pressure oil transfer tube assembly replace the Part Number 3019268 and 3027054 tube assemblies with Part Number 3030150 tube assembly in accordance with Paragraph 2, accomplishment instructions in Pratt & Whitney Aircraft of Canada, Limited Service Bulletin No. 3099 or approved equivalent parts. Aircraft may be flown to a base for performance of maintenance required by this AD per FAR 21.197 or FAR 21.199. All equivalent parts must be approved by the Chief, Engineering and Manufacturing Branch of the Eastern Region of the FAA. This amendment is effective June 19, 1978. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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