# SDR CA980430032

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 21, 1998
- Submitted: March 26, 2000
- Operation: General aviation
- Engine: Allsn 501D13D
- Propeller: Allsn A6441FN606
- System (JASC): [6120 · Propeller Controlling System](https://openairdocs.org/jasc/6120)
- Part: Seal
- Part number: 687045021
- Condition: Pinched
- Location: Propeller
- Component: Aeroduct, 6505619
- Stage of operation: DE
- Nature of condition: J
- Precautionary procedure: A, E
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CA980430032

## Discrepancy

(CAN) DURING A SIMULATED EMERGENCY DESCENT THE PILOT DETECTED AN OVERSPEED OF THE NR 1 ENGINE. EMERGENCY PROCEDURES WERE CARRIED OUT AND THE ENGINE WAS SHUTDOWN AND THE PROPELLER FEATHERED. THE TRAINING MISSION WAS ABORTED AND THE AIRCRAFT LANDED.  THE OVERSPEED WAS ATTRIBUTED TO A PINCHED O-RING ON ONE OF THE PROPELLER REGULATING VALVES.

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