# SDR 95ZZZX2885

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 18, 1995
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N331MB
- Make and model: Piper PA-31-350
- Registry model: [Piper PA-31-350](https://openairdocs.org/model/piper-pa-31-350) (OpenAirDocs)
- Aircraft serial: 317405455
- System (JASC): [2434 · DC Generator-Alternator](https://openairdocs.org/jasc/2434)
- Part: Fan
- Part number: 902241
- Condition: Cracked
- Location: Alternator
- Part time: 833 hours
- Component: Prestolite, ALU8421LS
- Stage of operation: IN
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/95ZZZX2885

## Discrepancy

ALTERNATOR FAN WAS SUSPECTED TO BE CRACKED DUE TO FACE PLATE RUBBING THE DRIVE BELT.  ALTERNATOR WAS REMOVED AND FAN DISASSEMBLED. THERE WAS A CRACK FROM OUT OF THE DRIVE KEY HOLE, SPIRALING APPROXIMATELY ONE-HALF WAY AROUND THE FAN THEN GOING STRAIGHT TO A BLADE CUT OUT.  A SECOND CRACK HAD STARTED TO FORM A 'Y'.  THIS WAS ALSO GOING TOWARD A BLADE CUT OUT.  HAD IT PROGRESSED, APPROXIMATELY ONE-THIRD OF THE FAN WOULD HAVE DEPARTED THE ASSEMBLY.

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