# SDR UALA2012011200257

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 11, 2012
- Submitted: January 30, 2012
- Operation: Air carrier
- Aircraft: [N171UA](https://openairdocs.org/aircraft/N171UA), registered now
- Make and model: Boeing 747422
- Aircraft serial: 24322
- Aircraft time: 84,300 hours, 10,034 cycles
- Engine: Pwa PW4056
- System (JASC): [2170 · Humidity Control System](https://openairdocs.org/jasc/2170)
- Part: Circuit Card
- Part number: 285U0036211
- Part serial: 58
- Condition: Failed
- Stage of operation: NR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: H
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UALA2012011200257

## Discrepancy

"HUMID FLT DK"  EICAS ADVISORY MESSAGE DISPLAYED.  FLIGHT DECK HUMIDIFICATION SYSTEM FAILURE.  REPLACED ECS CARD. YMLA13 CARD. OPS CHECKED COVERED ON DF444. REPLACED & REINSTALLED FLIGHT DECK HUMIDIFIER, OPS TESTED GOOD.

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