# SDR DXTA2011071004647

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 10, 2011
- Submitted: July 11, 2011
- Operation: Air carrier
- Aircraft: [N922QS](https://openairdocs.org/aircraft/N922QS), registered now
- Make and model: Cessna 750
- Registry model: [Cessna 750](https://openairdocs.org/model/cessna-750) (OpenAirDocs)
- Aircraft serial: 7500293
- Aircraft time: 2,264 hours, 1,366 cycles
- System (JASC): [2910 · Hydraulic System, Main](https://openairdocs.org/jasc/2910)
- Part: O-Ring
- Condition: Leaking
- Location: Hyd System
- Stage of operation: CR
- How discovered: O
- Nature of condition: K
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DXTA2011071004647

## Discrepancy

IN CRUISE FLIGHT AT FL400, DURING CRUISE CHECKLIST, NOTED HYD VOL WAS 20 PERCENT AND DECREASING. ONCE HYD VOL A CAS ILLUMINATED FOLLOWED APPROPRIATE CHECKLIST AND LANDED WITHOUT INCIDENT.  DETERMINED HYD LEAK FROM RUDDER PCU UPPER UNIT HAD O-RING CUT ON PRESSURE LINE, REPLACED O-RING AND LEAKED CHECKED SATISFACTORY ALL WORK IAW MM 12-10-36 AND 32-40-00.  ALSO, SERVICED HYD SYS AND BLEED BRAKES AND LT MAIN HYD SYS.

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