# SDR 98ZZZX2812

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 6, 1998
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N159AC](https://openairdocs.org/aircraft/N159AC), registered now
- Make and model: Skrsky S64F
- Aircraft serial: 64084
- System (JASC): [2410 · Alternator-Generator Drive](https://openairdocs.org/jasc/2410)
- Part: Rollers
- Condition: Worn
- Location: Riding Surface
- Part time: 4,604 hours
- Component: 643520500048
- Stage of operation: CR
- Nature of condition: H
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/98ZZZX2812

## Discrepancy

SUBMITTER STATED THIS MDR AFFECTS S-64E MODEL.  ACFT WAS FLYING UNDER NORMAL CONDITIONS WHEN NR 1 AND NR 2 GEN WENT OFF-LINE AND INVERTER POWER WAS NEEDED FOR A/C TO RETURN TO LANDING.  INITIAL INSP REVEALED ALL WIRES CONNECTED AND CB'S IN CORRECT POSITIONS.  ALSO, NR 1 AND NR 2 GENERATOR SPLINED QUILL SHAFTS WERE SHEARED ALLOWING GEN DRIVE GEARS IN REAR ACCY COVER TO SPIN FREELY.  NEW SPLINED QUILL SHAFTS INSTALLED IN GENERATORS AND A/C CONTINUED IN SERVICE.  INVEST SHOWED EXCESS WEAR EXISITED RESULTING IN SLIPPAGE AND RE-ENGAGEMENT OF TTO FREE WHEEL UNIT.  SPLINED QUILL SHAFTS IN NR 1 AND NR 2 GENERATORS WERE BROKEN BECAUSE OF POLAR INERTIA OF GEN ROTORS WHEN TTO FREE WHEEL UNIT SLIPPED AND RE-ENGAGED.

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