# SDR 2026FA0000433

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 27, 2026
- Submitted: May 27, 2026
- Operation: General aviation
- Aircraft: [N506DR](https://openairdocs.org/aircraft/N506DR), registered now
- Make and model: Cessna 310R
- Registry model: [Cessna 310R](https://openairdocs.org/model/cessna-310r) (OpenAirDocs)
- Aircraft serial: 310R0185
- Aircraft time: 5,484 hours
- Engine: Cont IO520MB
- Engine time: 544 hours
- System (JASC): [2421 · AC Generator-Alternator](https://openairdocs.org/jasc/2421)
- Part: Alternator
- Part number: C28150
- Part serial: HZ012567
- Condition: Inoperative
- Location: Zone 400
- Part time: 544 hours
- Stage of operation: CR
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2026FA0000433

## Discrepancy

THE PILOT REPORTED THE LH ALTERNATOR FAILURE LIGHT ILLUMINATED IN FLIGHT, WITH THE LH ALTERNATOR INDICATING NO ELECTRICAL OUTPUT. THE ALTERNATOR WAS INSTALLED ON 05/20/2025 AT AN AIRFRAME TOTAL TIME OF 4939.8 HOURS AND WAS REMOVED AS INOPERATIVE ON 05/14/2026.  AT THE TIME OF REMOVAL, THE ALTERNATOR HAD ACCUMULATED APPROXIMATELY 544.2 HOURS IN SERVICE.  DURING THE UNIT'S EVALUATION, WE WERE INFORMED THAT MATERIAL DESCRIBED AS RESEMBLING “ALUMINUM FOIL” WAS FOUND INTERNALLY. WE WERE ALSO ADVISED THAT IT APPEARED SOMETHING INSIDE THE ALTERNATOR MAY HAVE BEEN COMING APART INTERNALLY, AND THAT THIS WAS NOT SOMETHING NORMALLY SEEN.

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