# SDR UPXC20190823001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 13, 2019
- Submitted: August 24, 2019
- Operation: Air carrier
- Aircraft: [N555EL](https://openairdocs.org/aircraft/N555EL), registered now
- Make and model: Robsin R44RAVENII
- Aircraft serial: 10665
- Aircraft time: 2,978 hours
- Engine: Lyc IO540AE1A5
- Engine time: 2,978 hours
- System (JASC): [8530 · Reciprocating Engine Cylinder Section](https://openairdocs.org/jasc/8530)
- Part: Intake Valve
- Part number: 17A23937
- Condition: Fragmented
- Location: Nr 1 Cylinder
- Part time: 778 hours
- Component: Cylinder, Lyc
- Component part number: LW12993
- Stage of operation: CR
- How discovered: O
- Nature of condition: R, E
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UPXC20190823001

## Discrepancy

THE PILOT HEARD/FELT A POP, HAD AN INCREASE IN VIBRATION, AND A PARTIAL LOSS OF POWER. HE MADE AN EMERGENCY DESCENT TO A POWER ASSISTED LANDING IN THE TUNDRA, UPON LANDING SAW SMOKE COMING FROM THE ENGINE COMPARTMENT. SHUT DOWN AIRCRAFT.  FOUND NO EVIDENCE OF FIRE. OIL ON EXHAUST, SAW OIL IN THE ENGINE COMPARTMENT. CALLED MAINTENANCE. UPON MAINTENANCE GETTING THERE, WE FOUND THE INTAKE VALVE ON THE #1 CYLINDER WAS MISSING. FURTHER INVESTIGATION FOUND THE VALVE STEM AT THE KEEPERS HAD BROKEN, AND LET THE VALVE FALL INTO THE CYLINDER. WE FOUND THE PARTS OF THE VALVE IN THE INTAKE SYSTEM OF THE ENGINE. THE PISTON AND THE CYLINDER HEAD WERE HAMMERED.

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