# SDR TRBA2011007

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 10, 2011
- Submitted: January 13, 2011
- Operation: Air carrier
- Aircraft: [N494AE](https://openairdocs.org/aircraft/N494AE), registered now
- Make and model: Aerosp ATR 72-212A
- Registry model: [Aerosp ATR 72-212A](https://openairdocs.org/model/aerospatiale-atr-72-212a) (OpenAirDocs)
- Aircraft serial: 494
- Aircraft time: 22,469 hours, 26,554 cycles
- Engine: Pwc PW127F
- Engine time: 19,469 hours, 23,273 cycles
- System (JASC): [7230 · Turbine Engine Compressor Section](https://openairdocs.org/jasc/7230)
- Part: Servo Valve
- Part number: 311864201
- Part serial: WDA08058
- Condition: Malfunctioned
- Location: Zone 400
- Stage of operation: CL
- How discovered: O
- Nature of condition: R, J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/TRBA2011007

## Discrepancy

AFTER T/O ENGINE NR1 HAD A COMPRESSOR STALL. TORQUE SPIKED 10 PERCENT.  PERFORMED GROUND RUN PERFORMANCE CHECK NR1 ENG IAW ATR72 JIC 72-00-00-ERU 10040.  NO DEFECTS NOTED.  CANNOT DUPLICATE.  ACFT TAKEN OUT OF SERVICE FOR SUSPECTED COMPRESSOR STALLS ON NR1 ENG.  R & R NR1 ENGINE INTER COMPRESSOR BLEED VALVE (IBV) AND (IBV) SERVO VALVE ON NR1 ENGINE IAW MM 72-01-30.  ENGINE NR1 GROUND RUN, NR1 ENG IBV AND SERVO VALVE.  OPS TEST GOOD IAW MM 72-01-30.

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