# SDR UALA2012010300049

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 28, 2011
- Submitted: January 11, 2012
- Operation: Air carrier
- Aircraft: N598UA
- Make and model: Boeing 757222
- Aircraft serial: 28751
- Aircraft time: 50,910 hours, 14,267 cycles
- Engine: Pwa PW2037
- System (JASC): [2197 · Air Conditioning System Wiring](https://openairdocs.org/jasc/2197)
- Part: Relay
- Condition: Failed
- Location: Rt Ac Pack
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UALA2012010300049

## Discrepancy

COCKPIT AIR NOISE IS VERY LOUD.  CHECKED FLIGHT DECK NOISE LEVEL PER SERVICE TIP 21- 22-00 PAGE 902 STEP 7.  NOISE LEVEL INDICATED A GREATER THAN 3DB CHANGE WHEN RT RECIRCULATION FAN WAS SELECTED.   FOUND THE RIGHT PACK STUCK IN HIGH FLOW.  REPLACED CONTROL VALVE CARD M864, NO HELP.  REPLACED RELAY K416, CHECKED OKAY.

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