# SDR 97ZZZX1277

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 6, 1997
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N407AL](https://openairdocs.org/aircraft/N407AL), registered now
- Make and model: Bell 407
- Registry model: [Bell 407](https://openairdocs.org/model/bell-helicopter-textron-canada-407) (OpenAirDocs)
- Aircraft serial: 53044
- System (JASC): [6510 · Tail Rotor Drive Shaft](https://openairdocs.org/jasc/6510)
- Part: Disc Pack
- Part number: 406090340101
- Condition: Cracked
- Location: Nr 6 T/R Shaft
- Part time: 309 hours
- Component: 407040302101
- 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/97ZZZX1277

## Discrepancy

DURING A 50-HOUR INSPECTION, FOUND T/R COUPLING DISC PACK, P/N 406-090-340-101, TO HAVE A CRACK ON ONE OUTER LAMINATE EXTENDING THREE-FOURTHS OF THE WAY THROUGH THE LAMINATE.  THE DESIGN OF THIS AIRCRAFT DOES NOT ALLOW THE NR 4 THROUGH THE NR 7 (ALL OF THEM ON THE TAILBOOM) T/R DRIVESHAFTS TO FLOAT.  IT IS GOING TO BE HARDER ON DISC PACS THAN A 206L.  THIS IS THE THIRD OCCURRENCE OF THIS PROBLEM ON A FLEET OF TWO A/C WITH 550 HOURS FLIGHT TIME COMBINED.

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