AD 77-05-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Continental Motors | IO-470-L | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | IO-520-D | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | IO-520-F | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | IO-520-L | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | TSIO-520-C | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | TSIO-520-G | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | TSIO-520-H | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | TSIO-520-M | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
| engine | Continental Motors | TSIO-520-R | TELEDYNE CONTINENTAL MOTORS Model IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L Engines |
Unsafe Condition
Crankshaft failure due to potential bearing distress indicated by metal contamination in oil filter/screen or propeller control system malfunctions affecting RPM consistency.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect propeller operation at intervals not exceeding 10 hours time in service until 100 hours total time, examine oil filter/screen for metal contamination every 25 hours until 100 hours total time, and perform additional checks on propeller control, governor, and propeller if RPM drop不足400 or feathering occurs. Contact specified FAA-DER for disposition if discrepancies found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Compliance required as indicated after the effective date of this AD unless already accomplished.
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Affected Aircraft
Teledyne Continental Motors engines: IO-520-D, IO-520-F, TSIO-520-C, TSIO-520-G, TSIO-520-M, TSIO-520-R, IO-520-L, TSIO-520-H, and IO-470-L installed on specific Cessna and Beech aircraft serial ranges as listed in the AD.
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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