AD Amdt-39-11290
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Continental | Motors O-470 | Airworthiness Directives; Teledyne Continental Motors O-470, IO- 470, TSIO-470, IO-520, TSIO-520, LTSIO-520, GTSIO-520, IO-550, TSIO- 550, and TSIOL-550 Series Reciprocating Engines |
Unsafe Condition
Crankshaft cheek cracks could lead to crankshaft failure, resulting in total engine power loss, in-flight engine failure, and possible forced landing.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the No. 2 and No. 5 crankshaft cheeks for cracks using visual and ultrasonic (UT) methods. Replace any crankshaft found with a cracked cheek with a serviceable crankshaft. Revise the AFM to incorporate the revised service bulletin clarifying snap ring installation.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 500 hours time-in-service (TIS) for engines that require a more immediate inspection; before further flight for engines with cracked cheeks.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Teledyne Continental Motors O-470, IO-470, TSIO-470, IO-520, TSIO-520, LTSIO-520, GTSIO-520, IO-550, TSIO-550, and TSIOL-550 series reciprocating engines, including additional engines identified by serial numbers (S/Ns).
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.