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.
AI-generated summary from the source AD text. Verify against the official source before acting.
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.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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