# SDR ALG2002F00011

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 25, 2002
- Submitted: February 21, 2002
- Operation: Air carrier
- Aircraft: [N937AL](https://openairdocs.org/aircraft/N937AL), registered now
- Make and model: Bell 407
- Registry model: [Bell 407](https://openairdocs.org/model/bell-helicopter-textron-canada-407) (OpenAirDocs)
- Aircraft serial: 53383
- Engine: Allsn 250C47B
- System (JASC): [6320 · Main Rotor Gearbox](https://openairdocs.org/jasc/6320)
- Part: Pinion Gear
- Part number: 6893672
- Part serial: NN76809
- Condition: Galled
- Location: Gearbox
- Part time: 3,190 hours
- Component: Gearbox, Allsn, C47B
- Component part number: 23063393
- Stage of operation: IN
- 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/ALG2002F00011

## Discrepancy

CHIP LIGHT LUMINATED, HAVING METAL IN OIL.  UPON DISASSEMBLY OF GEARBOX, FOUND EXCESSIVE GALLING ON GEAR TEETH (PINION GEAR).  EXCESSIVE GALLING ON PINION GEAR DUE TO IMPROPER GEAR MESHING AND EXCESSIVE LOAD TO TORQUE AREA.  INSURE GEAR HARDNESS AND PROPER MESHING OF GEAR TEETH.

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