# SDR UALA2012090705055

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 7, 2012
- Submitted: September 12, 2012
- Operation: Air carrier
- Aircraft: [N121UA](https://openairdocs.org/aircraft/N121UA), registered now
- Make and model: Boeing 747422
- Aircraft serial: 29167
- Aircraft time: 56,120 hours, 6,576 cycles
- Engine: Pwa PW4056
- System (JASC): [3040 · Windshield/Door Rain/Ice Removal](https://openairdocs.org/jasc/3040)
- Part: Control Unit
- Part number: S283U0035
- Part serial: 52
- Condition: Inoperative
- Location: Window Heat
- Stage of operation: NR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UALA2012090705055

## Discrepancy

NR 1 RIGHT WINDOW HEAT INOPERATIVE.  NO CONTROLLER.  REPLACED RIGHT WHCU PER MM.  ALSO REPLACED RIGHT WINDOW HEAT SWITCH.  GROUND TEST PASS.

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