# SDR CA971021023

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 2, 1997
- Submitted: March 26, 2000
- Operation: General aviation
- Make and model: Bell 407
- Registry model: [Bell 407](https://openairdocs.org/model/bell-helicopter-textron-canada-407) (OpenAirDocs)
- System (JASC): [6510 · Tail Rotor Drive Shaft](https://openairdocs.org/jasc/6510)
- Part: Disc Pack
- Part number: 406040340101
- Condition: Cracked
- Location: Nr 7 Aft Outer
- Part time: 303 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/CA971021023

## Discrepancy

(CAN) AS PER AD CF-97-19, INSPECTION OF TAIL ROTOR DRIVE SHAFT THOMAS COUPLINGS CARRIED OUT.  THE AFT OUTER DISC OF THE NR 7 DISC PACK WAS FOUND BROKEN IN TWO PLACES.  DISC PACKS TAKEN FOR TESTING BY BELL.  BHTC IS REDESIGNING DISCS TO OVERCOME MID-SPAN CRACKING.

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