AD 78-17-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Pratt & Whitney Canada Corp. | PT6A-38 | PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED Model PT6A-38, PT6A-41 and PT6A-45A Engines |
| engine | Pratt & Whitney Canada Corp. | PT6A-41 | PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED Model PT6A-38, PT6A-41 and PT6A-45A Engines |
| engine | Pratt & Whitney Canada Corp. | PT6A-45A | PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED Model PT6A-38, PT6A-41 and PT6A-45A Engines |
Unsafe Condition
Rupture of the bypass valve diaphragm in the fuel control unit.
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Required Actions
Replace part number 2526477 diaphragm with part number 343451 diaphragm in accordance with Pratt & Whitney Service Bulletin No. 3103 or approved equivalent parts and procedure.
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Compliance Time
within the next 100 hours in service, after the effective date of this AD, unless already accomplished
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Affected Aircraft
Pratt & Whitney Aircraft of Canada, Limited PT6A-38, PT6A-41 and PT6A-45A engines with fuel control unit Aviation Electric Part Numbers 3244723-3 through -10, 3244738-5, 3244738-6, 3244752-6 through -10, and 3244755-7 through -11.
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Federal Register Abstract
Fuel Control Unit
Applicability Source Text
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AD Final Rules - DRS_78-17-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-17-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED Model PT6A-38, PT6A-41 and PT6A-45A Engines Subject: Fuel Control Unit Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/31/1978 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 Model: PT6A-38 | PT6A-41 | PT6A-45A Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185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: 78-17-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3287 AD NUMBER: 78-17-07 SUBJECT HEADING: PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED Model PT6A-38, PT6A-41 and PT6A-45A Engines ACTION: SUMMARY: DATES: Effective August 31, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-17-07 PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED: Amendment 39-3287. Applies to all Pratt & Whitney Aircraft of Canada, Limited PT6A-38, PT6A-41 and PT6A-45A engines and Pratt & Whitney Aircraft PT6A-38 engines with fuel control unit Aviation Electric Part Numbers 3244723-3 through -10, 3244738-5, 3244738-6, 3244752-6 through -10, and 3244755-7 through -11. Compliance required within the next 100 hours in service, after the effective date of this AD, unless already accomplished. To preclude rupture of the bypass valve diaphragm in the fuel control unit, replace the part number 2526477 diaphragm with part number 343451 diaphragm in accordance with Paragraph 2, Accomplishment Instructions, in Pratt & Whitney Aircraft of Canada, Limited Service Bulletin No. 3103 or approved equivalent parts and procedure. Aircraft may be flown to a base for performance of maintenance required by this AD per FAR 21.197. Any equivalent parts and procedure must be approved by the Chief, Engineering & Manufacturing Branch of the Eastern Region of the Federal Aviation Administration (FAA). This amendment is effective August 31, 1978. FOOTER:
Document Text
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AD Final Rules - DRS_78-17-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-17-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED Model PT6A-38, PT6A-41 and PT6A-45A Engines Subject: Fuel Control Unit Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/31/1978 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: 78-17-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3287 AD NUMBER: 78-17-07 SUBJECT HEADING: PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED Model PT6A-38, PT6A-41 and PT6A-45A Engines ACTION: SUMMARY: DATES: Effective August 31, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-17-07 PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED: Amendment 39-3287. Applies to all Pratt & Whitney Aircraft of Canada, Limited PT6A-38, PT6A-41 and PT6A-45A engines and Pratt & Whitney Aircraft PT6A-38 engines with fuel control unit Aviation Electric Part Numbers 3244723-3 through -10, 3244738-5, 3244738-6, 3244752-6 through -10, and 3244755-7 through -11. Compliance required within the next 100 hours in service, after the effective date of this AD, unless already accomplished. To preclude rupture of the bypass valve diaphragm in the fuel control unit, replace the part number 2526477 diaphragm with part number 343451 diaphragm in accordance with Paragraph 2, Accomplishment Instructions, in Pratt & Whitney Aircraft of Canada, Limited Service Bulletin No. 3103 or approved equivalent parts and procedure. Aircraft may be flown to a base for performance of maintenance required by this AD per FAR 21.197. Any equivalent parts and procedure must be approved by the Chief, Engineering & Manufacturing Branch of the Eastern Region of the Federal Aviation Administration (FAA). This amendment is effective August 31, 1978. FOOTER:
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Retrieved: Apr 8, 2026
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