# SDR 95ZZZX6874

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 26, 1995
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N21240](https://openairdocs.org/aircraft/N21240), registered now
- Make and model: Bell 206L-1
- Registry model: [Bell 206L-1](https://openairdocs.org/model/bell-helicopter-textron-206l-1) (OpenAirDocs)
- Aircraft serial: 45647
- Engine: Allsn 250C28B
- System (JASC): [7250 · Turbine Section](https://openairdocs.org/jasc/7250)
- Part: Wheel
- Part number: 23001977
- Condition: Rim Break Out
- Location: Turb 3rd Stge
- Part time: 558 hours
- 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/95ZZZX6874

## Discrepancy

LOUD GRINDING, HIGH PITCH SQUEAL ACCOMPANIED BY TORQUE FLUCTUATIONS.  TEAR DOWN INSPECTION REVEALED 3RD STAGE WHEEL EXHIBITED RIM BREAK OUT OF 1.50 INCHES AND .25 INCH OF 2 EACH BLADES.  SUSPECT CAUSE OF FAILURE TO BE A STRESS CRACK ORIGINATING ON THE LEADING EDGE SIDE OF BREAK OUT IN REFERENCE TO DIRECTION OF ROTATION, ON THE TRAILING EDGE OF RIM SHROUD AND PROGRESSED APPROXIMATELY ONE-HALF OF CHORDAL LENGTH UNTIL OVERLOAD.  POWER TURBINE SECTION EXHIBITS EXCESSIVE KNIFE AND SEAL CONTACT AND BEARING AREA DAMAGE.  TOTAL CYCLES 980.

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