# SDR UALA2013012900548

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 28, 2013
- Submitted: February 15, 2013
- Operation: Air carrier
- Aircraft: [N643UA](https://openairdocs.org/aircraft/N643UA), registered now
- Make and model: Boeing 767322
- Aircraft serial: 25093
- Aircraft time: 93,241 hours, 14,745 cycles
- Engine: Pwa PW4060
- Engine time: 66,674 hours, 7,752 cycles
- System (JASC): [7200 · Engine (Turbine/Turboprop)](https://openairdocs.org/jasc/7200)
- Part: Engine
- Condition: Surges
- Location: Nr 1
- Stage of operation: DE
- How discovered: O
- Nature of condition: R
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UALA2013012900548

## Discrepancy

NR 1 ENGINE SILENT SURGE CHECKS.  ECM DETECTED A 'SILENT' SURGE AT OR NEAR TOP OF DESCENT AT LOW POWER ON FLT 959-28.  ECM DOES NOT SHOW ANY PARAMETER SHIFTS BEFORE THE SURGE.  THIS IS THE SECOND SURGE WITHIN A WEEK.

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